CN1075604C

CN1075604C - Pump and water turbine, and processes for mfg. same

Info

Publication number: CN1075604C
Application number: CN97122814A
Authority: CN
Inventors: 冈田亮二; 石川精一; 依田裕明; 田口启二; 植山淑治; 新仓和夫; 吉川次雄
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 1996-10-25
Filing date: 1997-10-24
Publication date: 2001-11-28
Anticipated expiration: 2017-10-24
Also published as: CN1210497C; CN1184898A; CN1313466A

Abstract

To improve the wear resistance under the condition where earth and soil is contained in the fluid by forming a region in which the Ni alloy film, the film of the boron diffusion layer, etc., are formed, and a region in which the film containing metals and carbides is formed on surfaces of an impeller and a casing in contact with the fluid. In an impeller 2 of a horizontal shaft pump to boost and discharge the water sucked from each end of the impeller through the rotation, an Ni alloy plating film is formed on the whole surface of the impeller 2 made of cast steel, etc., containing 13% chromium. However, in the regions of the impeller 2 where the flow speed is high, and where the particle collision frequency is high, i.e., outlet parts 22a, 23a and suction parts 22b, 23b of the blades 22 and a shroud 23, the film of the double-layered structure in which the Cr spray film (Cr3 C2 -20% NiCr spray film) of 0.4-0.6 mm film thickness and containing 16 wt.% Cr3 C2 and 4 wt.% Ni is executed on an upper layer covered with the Ni alloy film, to improve the wear resistance.

Description

The method of pump and this pump of manufacturing

The present invention relates to a kind of method that has the pump of fabulous corrosion resistance and make this pump.

In recent years, pump and water turbine are used under the situation that contains a kind of solid matter such as the grains of sand in the fluid more and more.This pump that turns round under like this situation at its rotor and shell position, can be subjected to the wearing and tearing (being called as " sandstone wearing and tearing ") that a kind of bump of solid matter causes and the synthetic damage of cavitating and causing.Therefore, the impaired position of expectation meeting will be repaired termly with the filler that has a resin such as rubber work to serve as a contrast or be coated with a kind of high hardness material such as pottery.Japanese unexamined and disclose this technology among the disclosed patent application 3-47477.

When pump or water turbine are used in the following time of situation of containing the grains of sand in the fluid, as mentioned above, each member must be coated with the infringement of last layer high hardness material to prevent that grains of sand wearing and tearing and cavitation erosion from causing.But rotor and shell have 3D shape, the material that difficult coating is harder.

Plating Cr is widely used in making has the highest face temperature film hardness, and also, Vickers hardness (being designated hereinafter simply as " Hv ") reaches about 1000.As for metallide, because due to the shape, electrolyte concentration is difficult to form the film of an even thickness, also be difficult to form a good skin covering of the surface, such as the channel inner surface away from electrode.Have again,, be difficult to the film thickness that formation one has enough life-spans at the pump that is used for handling the fluid that contains the solid particles such as the grains of sand.

Cr is similar with plating, and plating Ni-P or Ni-P-B are plated by electroless plating, and it is used to improve abrasion resistance and corrosion resistance widely, always and can form one no matter how its shape has the skin covering of the surface of a uniform thickness.But coating itself can not provide enough hardness and degree of adhering to, and therefore can not show enough desertification stone mills and decrease ability when it contacts with a high-velocity fluid.Simultaneously, be difficult to provide a film thickness with enough life-spans.The result, find that independent plating is difficult to present a kind of enough desertification stone abrasivenesses and the corrosivity of resistance to wearing, during in particular for the outer surface of the outlet end of the blade that contacts with high-velocity fluid and rotor, more difficultly show enough desertification stone abrasivenesses and the corrosivity of resistance to wearing.

Boronising and chromising all belong to a kind of surface treatment that improves abrasion resistance by boronising and chromium in a superficial layer to form a permeable formation with higher hardness.This surface treatment even can be applied in complex surface is to provide a higher relatively hardness.Therefore but the thickness of this permeable formation is restricted, is difficult to make process a pump that contains the fluid of solid particles such as the grains of sand and form a film thickness with enough life-spans.One relative higher hardness can reach, and still, when it contacts with the high-velocity fluid that contains solid particles, can not show enough abrasion resistances.As a result, when this surface-treatment applications during in the rotor outer surface that contacts with high-velocity fluid and blade exit, be difficult to show alone a kind of enough desertification stone abrasiveness and cavitation resistance.

One hard skin covering of the surface, the rigid surface film as forming by a kind of flame coating process has an enough desertification stone abrasiveness and cavitation resistances, and can coat a skin covering of the surface with an adequate thickness with comparalive ease.But there are the following problems for this flame coating process.Specifically, need a suitable distance between flame coating rifle and member, forming a satisfied flame coated surfaces film, and need a relevantly lenient space, this has certain limitation with regard to having caused the size to rifle.As a result, one has the member of a three-dimensional dimension and a narrow space so that be difficult to be coated with in whole zone the satisfied skin covering of the surface with enough hardness and enough adhesive force of last layer.For example, rotor can form satisfied skin covering of the surface at the blade tip that the coating such as flame is easier to carry out, still, and the skin covering of the surface that channel interior such as root of blade then is satisfied with in view of the narrow and small very difficult formation one in space.Although the velocity ratio blade tip of channel interior fluid is low,, the sandstone wearing and tearing still can take place, so that at the state of being untreated, can not reach enough life-spans.

The problem of specifically being enumerated above prior art can not solve.

The present invention makes every effort to address these problems, and its objective is, a kind of fabulous resistance to wearing and the pump of corrosion resistance that have is provided, these pumps even can be used under the situation that contains sandstone in the fluid.

Another object of the present invention provides a kind ofly has fabulous resistance to wearing and the method for the pump of corrosion resistance with a reasonable cost manufacturing one, these pumps even can be used under the situation that contains sandstone in the fluid.

For achieving the above object, this pump has adopted following structure.Have such structure with the surface of contacted rotor of fluid (impeller) and shell, promptly comprise: one is coated with one from comprising a Ni alloy surface film, the zone of the first surface film of selecting in the skin covering of the surface group of a boride layer skin covering of the surface and a chromising laminar surface film; Reach one and be coated with the zone that contains a kind of metal and a kind of carbide and second surface film.

The second surface film comprises: a kind of metal that contains at least a metal of selecting from the metal group that comprises Ni, Cr and Co; With a kind of chromium carbide or Tungsten carbite.

First surface film and second surface be intermembranous one deck overlap region, and the first surface film is clipped between rotor and shell and the second surface film in this zone.

The second surface film is a kind of 50 to 90 weight percents, preferably skin covering of the surface of the chromium carbide of 70 to 90 weight percents or Tungsten carbite of containing.

Ni alloy surface film is to be made by a kind of Ni alloy, and this Ni alloy contains: the P of 1 to 10 weight percent; 0.5 B to 5 weight percents; Or the B of the P of 1 to 10 weight percent and 0.5 to 5 weight percent.Also, Ni alloy surface film is to be made by a kind of Ni alloy, and this Ni alloy contains: the P of 1 to 10 weight percent; 0.5 B to 5 weight percents; Or the B of the P of 1 to 10 weight percent and 0.5 to 5 weight percent.This Ni alloy is impregnated with and includes the particulate of 5 to 10 weight percents, and this particulate is SiC, Si at least ₃N ₄, SiO ₂, AL ₂O ₃And ZrO ₃In a kind of.

Following method is as the method for making a pump.

The manufacture method of this pump comprises: form a Ni alloy surface film at rotor surface and inner surface of outer cover, these rotor surfaces and inner surface of outer cover have been processed into reservation shape, form a boride layer or form a Chromizing Layer; Be coated with and apply a skin covering of the surface, this skin covering of the surface comprises that chromium carbide or tungsten carbide reach at least a metal of selecting from the group that comprises Ni, Cr and Co; Under 400 to 600 ℃ of temperature, heat.

In this manufacture method, Ni alloy surface film is coated with by electric plating method and applies.Boride layer or chromising layer form by the powder diffusion method.This skin covering of the surface of at least a metal that contains chromium carbide or Tungsten carbite and select from the group that includes Ni, Cr and Co is coated with up with the flame coating process.

The present invention who solves foregoing problems has following function and effect.

(1) following function is to reach by be coated with Ni alloy surface film on rotor surface that contacts with fluid and inner surface of outer cover with effect.

This Ni alloy surface film is relative splendid aspect abrasion resistance and corrosion resistance.

(2) following function and effect reach by producing Ni alloy surface film.This Ni alloy contains the P of 1 to 10 weight percent, the P of the B of 0.5 to 5 weight percent or 1 to 10 weight percent and the B of 0.5 to 5 weight percent; Or this Ni alloy diffusion and that include 5 to 10 percentage by weights is SiC, Si at least ₃N ₄, SiO ₂, AL ₂O ₃And ZrO ₃In a kind of particulate.

Can with the method for plated by electroless plating with this Ni alloy surface film be coated in a member even a flame coating process on the member with complicated shape that can not carry out, make this member have the uniform skin covering of the surface of a thickness.As a result, whole surface comprises that the passage inner face can be electroplated, thereby has improved resistance to wearing and corrosion resistance of whole pump, has therefore also integrally improved the reliability of this pump.Have again, by containing: the P of 1 to 5 weight percent; 0.5 B to 2 weight percents; Or the Ni alloy of the B of the P of 1 to 10 weight percent and 0.5 to 5 weight percent can be obtained splendid resistance to wearing and corrosion resistance.Thereby, the zone that flame coating institute can not be coated with can be electroplated, thus by on whole surface (comprising the channel surface of rotor and the internal surface of shell), plate Ni alloy surface film make flame apply the zone that can not be coated with have better resistance to wearing and corrosion resistance.

(3) following function and effect are to be from SiC, Si at least by what add 5 to 10 weight percents in Ni alloy surface film ₃N ₄, SiO ₂, AL ₂O ₃And ZrO ₃In a kind of particulate of selecting obtain.

With regard to the Ni alloy surface film (being also referred to as " Ni alloy plating film ") that makes by galvanoplastic, for example, comprise the P of 1 to 10 weight percent; 0.5 B to 5 weight percents; Or the Ni alloy plating film of the B of the P of 1 to 10 weight percent and 0.5 to 5 weight percent, adopt a kind of appropriate heat treatment process can generate a kind of hard sludge, to obtain maximum skin covering of the surface hardness (Hv800 to 1000 according to appointment).With regard to the impact of opposing sandstone particle, this skin covering of the surface is more hard more good, and, have one than the hardness of the quartz in the sandstone particle also the skin covering of the surface of high hardness is splendid in performance aspect the desertification stone mill damage.If in this Ni alloy plating film, be dispersed with hard particles, such as SiC, Si ₃N ₄, SiO ₂, AL ₂O ₃And ZrO ₃, the hardness of this skin covering of the surface can further increase so, thereby improves abrasion resistance.Herein, this hard particles such as SiC, Si ₃N ₄, SiO ₂, AL ₂O ₃And ZrO ₃Content, the hardness that improves skin covering of the surface when its percentage by volume surpasses 5% is very remarkable, when it then can increase the fragility of skin covering of the surface above 10% the time.Therefore this content preferably accounts for 5 to 10% on percentage by volume.

(4) following function and effect are to reach in 0.1 to 0.3mm by the thickness setting with Ni alloy plating film.

For Ni alloy surface film, thickness is that 0.02mm just can show splendid corrosion resistance.But, at relative low-speed region, on the passage inner face, need one greater than the thickness of 0.1mm so that enough desertification stone abrasivenesses to be provided.On the other hand, when maintaining this pump termly, for the ease of repairing this Ni alloy surface film, this thickness is that 0.3mm is just enough.For saving material and the consideration of electric power, thickness 0.1 to 0.3mm is proper.

(5) following function and effect are by at the rotor surface that contacts with the processing fluid-phase with inner surface of outer cover forms boride layer or Chromizing Layer is obtained.

Boride layer or chromising layer are a kind of hard layers, and this hard layer is to form to be settled out tiny compound phase of hard boron or the compound phase of hard chromium by boron or chromium are diffused into the parent metal from outer surface.Therefore, adhesive quality is splendid, and hardness is higher relatively, thereby a kind of fabulous corrosion resistance is provided.As illustrate the words of the method that forms this diffusion layer with Powder Diffusion, this Powder Diffusion is that parent metal and the used pulvis that changes into thin pulp are together heated or heat in pulvis, so just can set up diffusion phase at the passage inner face, the relatively large member of size also can be processed simultaneously.Therefore, boride layer and Chromizing Layer formed whole (comprising the channel interior of rotor and the inner surface of shell), and so just can make those is that flame applies can not be coated with regional coated, thereby splendid resistance to wearing and corrosion resistance is provided.

The thickness of boride layer or Chromizing Layer also is to determine heating-up temperature and heat time heating time by diffusivity.Consider that continuous high temperature can reduce the intensity and the abrasion resistance of rotor and shell, the heating-up temperature when therefore handling has the upper limit.Along with the increase of thickness, the stress in the diffusion layer also can increase, so that cracking and spalling.On the other hand, in relative low velocity zone, as presenting a kind of enough abrasion resistances on the passage inner face, thickness is necessary for 0.1mm or thicker.Have, because in the maintenance period, maintain termly this pump, so thickness 0.3mm is just enough, for saving material and the consideration of electric power, thickness 0.1 to 0.3mm is proper.

(6) following function and effect obtain from a kind of skin covering of the surface, this skin covering of the surface be suitable for being coated in at least one part of the contacted rotor surface of the fluid of handling and inner surface of outer cover, and contain chromium carbide or Tungsten carbite, and at least a metal of from Ni, Cr and Co, selecting.

Adopt Cr ₃C ₂Have a Hv1000 or higher hardness and a splendid corrosion resistance as chromium carbide and WC as this skin covering of the surface of tungsten carbide.The main matter of forming sandstone is feldspar and quartz, and quartz maximum hardness wherein is Hv1000.When the hardness of impinging particle surpassed the hardness of skin covering of the surface, aspect resistance to wearing, the sandstone wearing and tearing sharply increased, and were that the skin covering of the surface of Hv1000 can show enough desertification stone or cavitation resistive property by cover one deck hardness at least a portion rotor surface.

(7) function and effect below reach by generating a kind of skin covering of the surface.This skin covering of the surface comprises chromium carbide or Tungsten carbite and at least a metal of selecting from the one group of metal that is made of Ni, Cr and Co.Chromium carbide (Cr in this skin covering of the surface ₃C ₂) or the weight content of tungsten carbide (WC) be 50% to 90%, preferably 70% to 90%.

This hardness of chromium carbide or tungsten carbide and at least a metallic surface film of selecting from Ni, Cr and Co metal group that comprises is according to Cr ₃C ₂Or the difference of WC content can change to some extent.If, Cr ₃C ₂Or WC content increases, and the hardness of skin covering of the surface increases, but toughness descends, and becomes fragile simultaneously, thereby is easy to fragmentation or decortication and reduces reliability.If, Cr ₃C ₂Or the weight content of WC is in the 50%-90% scope, and skin covering of the surface can keep enough desertification stone mills to decrease hardness and toughness.And in this scope, skin covering of the surface hardness is Hv1000 or higher, so that it has enough anticorrosive and desertification stone mills to decrease ability.But, if sandstone density height, Cr ₃C ₂Or the weight content of WC has to increase, to improve the hardness of skin covering of the surface.In this case, suitable Cr ₃C ₂Or the WC weight content is 70%-90%.

(8) Xia Mian function and effect are to reach by be coated with thick 0.1 to 1.0mm the film of last layer at skin covering of the surface, and this tunic comprises chromium carbide or Tungsten carbite and at least a metal of selecting from Ni, Cr and Co.

Because, a lot of trickle holes are arranged on the flame coated film, its thickness should be 0.1mm or thicker, to present enough anticorrosive and antiwear properties.On the other hand, when the thickness of flame coated film increased, its internal stress also can increase, thereby tack is reduced.On the tack this point, the thickness of flame coated film must be 1.0mm or thinner.And, consider the abrasion resistance of skin covering of the surface, be that life-span of film of 1.0mm is just enough for thickness.In order to save material and electric power, thickness be 1.0mm or thinner be suitable.Do further to discuss, thickness be 0.1 to 1.0mm film rotor desertification stone mill decrease and cavitation erosion in just can guarantee enough life-spans, output and the meeting of energy-conservation aspect are satisfactory.

(9) Xia Mian function and effect reach with a kind of flame coating process coated surfaces film, and this laminar surface film comprises chromium carbide or Tungsten carbite and at least a metal of selecting from Ni, Cr and Co.

By using the flame coating process, can get 0.1 to 1.0mm thickness by the skin covering of the surface that Ni, Cr or Co and chromium carbide are formed, can get 0.1 to 0.5mm thickness by the skin covering of the surface that Ni, Cr or Co and Tungsten carbite are formed.So it is possible adopting the flame coating process to apply the skin covering of the surface that this layer have thickness like this, its thickness be enough to the desertification stone mill decrease and cavitation erosion in guarantee enough life-spans.

Flame is coated with diverse ways, be suitable for according to its pluses and minuses separately.The flame coating process that can form compact surfaces film is a vacuum flame coating process, and the plasma torch coating is carried out in a vacuum in the method.But according to this vacuum flame coating process, pending member must be put into a vacuum chamber that is used to apply processing, so it in the present embodiment, and it is unpractical being applied to pumping element.Illustrate the method that another kind can apply a fine and close skin covering of the surface with a kind of explosive flame coating process and a kind of quick flame coating process.The explosive flame coating process just can cover a wider applicator surface in once spraying, so it is suitable for covering a large-sized flat member.But flame spraying gun and equipment size are bigger, thereby so that detonation flame spraying is difficult to member such as rotor or the shell that quality applies three-dimensional dimension equably.Flame spraying can form the skin covering of the surface of a densification fast, and available one less relatively spray gun, so it can form a fine and close skin covering of the surface on the three-dimensional dimension member.So flame spraying is more suitable for this fast

Embodiment.

(10) Xia Mian function and effect be by with contacted rotor surface of processing fluid and inner surface of outer cover on form a first surface film and reach, this first surface film is selected from a Ni alloy surface film, a boride layer skin covering of the surface and a chromising laminar surface film, and covers a second surface film that contains at least a metal of selecting and chromium carbide or Tungsten carbite from the metal group that comprises Ni, Cr and Co on the first surface film.

As mentioned above, flame spraying is used the rifle of a less fast, and can form the uniform skin covering of the surface of a quality at a three-dimensional dimension member, still, finds that still it is difficult to some part at pump, such as the channel interior of rotor, forms gratifying skin covering of the surface.On the other hand, Ni alloy plating film, boride layer and chromising layer are inferior to the flame coated film on desertification stone mill damage and cavitation erosion property, but it can be implemented on a narrow space, thus they in addition can be coated with on the channel interior as rotor and apply a gratifying skin covering of the surface in these parts.So, by in being difficult to the passage of filming or on this whole passage, forming Ni alloy plating film, boride layer and chromising layer with flame spraying, and the skin covering of the surface that flame spraying is made up of chromium carbide or Tungsten carbite and Ni, Cr or Co on same area, the desertification stone abrasiveness and the cavitation resistance of rotor and shell have had rapid raising on the whole.

(11) Xia Mian function and effect be by with contacted rotor surface of processing fluid and inner surface of outer cover on form a first surface film and reach, this first surface film is selected from a Ni alloy surface film, a boride layer skin covering of the surface and a chromising laminar surface film, and on the first surface film, cover a second surface film that contains at least a metal of from the metal group that comprises Ni, Cr and Co, selecting and chromium carbide or Tungsten carbite, and with it 400 to 600 ℃ of heating down.

By this heat treatment, Ni alloy plating film diffuses in the parent metal, has increased adhesive quality.Have again, the intermembranous overlapping part of the first surface film of any one formation or first diffusion layer and the second surface that contains chromium carbide or Tungsten carbite and at least a metal of selecting from Ni, Cr and Co produces diffusion in Ni alloy coating, a boride layer and a chromising layer, thereby the adhesive quality between two skins covering of the surface is improved.The raising of this adhesive quality aspect causes the desertification stone mill to decrease ability and anti-skin covering of the surface peels off the restraint raising, correspondingly, has improved the reliability of entire pump.Consider diffusivity, preferably adopt higher heating-up temperature.But, can produce thermal stress in view of thermal coefficient of expansion between skin covering of the surface and parent metal is different, heating-up temperature is preferably 600 ℃ or lower.On the other hand, at 400 ℃ or more during low temperature, diffusion needs a very long time, so that is difficult to use in industry.

(12) Xia Mian function and effect are by adopting a Ni-P-B electroplating film to reach as the heat treatment of Ni alloy plating film.

Usually, this Ni-P-B electroplating film by with it in about 350-400 ℃ heating, hard layer separated out and have a maximized surface film hardness, can reduce this skin covering of the surface hardness by under another higher temperature, heating.But when hardness increased, skin covering of the surface became fragile, thereby cause ftractureing/peel off.But when needs possessed antiwear property, this Ni-P-B electroplating film was heated to 350 to 400 ℃ usually so that it has highest hardness.In the present invention, skin covering of the surface is used for resisting the impact of the grains of sand of water, still, must avoid the cracking of this skin covering of the surface/peel off, main cracking because of skin covering of the surface/peel off and will excite corrosion, therefore the heat treatment that makes skin covering of the surface have highest hardness is not best choice.In 400 to 600 ℃ of temperature ranges, neither cause surface embrittlement, can not make hardness reach maximum again, but, obtained a higher relatively skin covering of the surface hardness, providing the reliability higher skin covering of the surface, the cracking of this skin covering of the surface by having suppressed skin covering of the surface to the parent metal diffusion/peel off.

On the other hand, as described below, by this kind heat treatment, this skin covering of the surface that contains chromium carbide or Tungsten carbite and at least a metal of selecting from the metal group that comprises Ni, Cr and Co is improved aspect film quality.By this heating, the adhesive force between the Metal Phase of the Ni in the skin covering of the surface, Cr or Co and chromium carbide particulate or tungsten carbide particulate increases, thereby skin covering of the surface hardness is increased, and has so just improved the desertification stone mill and has decreased ability and anti-cavitation erosion ability.As a result, skin covering of the surface peel off and disengaging is suppressed, reliability improves, in addition when one impact skin covering of the surface is ftractureed after, still like this.Under higher heating-up temperature; adhesion between the metal of the Ni in the skin covering of the surface, Cr or Co and chromium carbide particulate or Tungsten carbite particulate increases; and the adhesion increase of the boundary between skin covering of the surface and the parent metal is faster; but, produced a kind of thermal strain because thermal expansion coefficient is different between skin covering of the surface and parent metal.Consider the impact of thermal strain his-and-hers watches facial mask, preferably making heating-up temperature is 600 ℃ or lower.Have, for the consideration to efficient, 400 ℃ of temperature are minimums again, will make heat treatment need long time if hang down again, so that be difficult in industrial application.

On the other hand, be to solve foregoing problems, in a hydraulic turbine, this hydraulic turbine comprises: the shell that a fluid passage is arranged in it; And layout in the enclosure and can make the fluid in the passage play the rotating member of rotation with one, can also comprise following any structure.

(A) fluid in this water turbine and its passage is contacted, at least on its part, scribbled: one includes the first surface film of at least a material of selecting from the group of being made up of chromium carbide, Tungsten carbite, nickel (also by writing " Ni "), chromium (also by writing " Cr ") and cobalt (also by writing " Co "); With a second surface film that comprises at least a material of from the group of forming by ebonite, epoxy resin, polyethylene and polyester, selecting.

(B) in (A), water turbine has a zone, scribbles the second surface film on this zone first surface film.

(C), and all scribble the second surface film on contacted whole of the fluid at (A) or (B).

(D) arrive in any one of (C) at (A), the first surface film contains 50 to 90 weight percents, the preferably chromium carbide of 70 to 90 weight percents or Tungsten carbite.

(E) at (A) in any one of (D), the first surface film has one 0.1 to 1.0mm thickness, and has one 1 to 3mm thickness by comprising skin covering of the surface that resin at least a in ebonite, epoxy resin, polyethylene and the polyester makes.

(F) arrive in any one of (E) at (A), in the second surface film, be dispersed with: or be iron, copper or stainless steel metal powder; It is the ceramic particle that aluminium oxide, titanium oxide, magnesium oxide, chromium oxide, silica, chromium carbide, Tungsten carbite, silicon carbide or silicon nitride form.

For addressing the above problem, make this hydraulic turbine by the method for any one step in may further comprise the steps.

(G) at least a portion of the face of a used unit is coated with a first surface film that contains at least a material of selecting from the group that chromium carbide, Tungsten carbite, nickel, chromium and cobalt are formed; Then be coated with one and comprise the second surface film that constitutes at least a material of selecting the group from ebonite, epoxy resin, polyethylene and polyester.

(H) in (G), behind the coating first surface film, before the coating second surface film, these parts 350 to 650 ℃ of temperature, were preferably heated 1 to 30 hour under 400 to 650 ℃ of temperature.

(I) at (G) or (H), scribble at least a portion second surface film on the first surface film.

(J) at (G) or (I), a kind of flame spraying, preferably a kind of quick flame spraying are used as the method for coating first surface film.

Obtain in the structure that following function and effect further describe from behind.

Has a high hardness owing to include the skin covering of the surface of at least a material of from the group that chromium carbide, Tungsten carbite, Ni, Cr and Co form, selecting, therefore, at least a portion coating first surface film by with the water turbine surface just can obtain desertification stone abrasiveness and cavitation resistance.Especially, adopt Cr ₃C ₂Have a Hv1000 or higher case hardness and a fabulous corrosion resistance as chromium carbide, employing WC as the skin covering of the surface of tungsten carbide.The main matter that comprises in the sandstone is feldspar and quartz, and the highest hardness of quartz is Hv1000.When the hardness of skin covering of the surface surpassed the hardness of impinging particle, antiwear property increased sharply, and therefore, by be about the skin covering of the surface of Hv1000 at least a portion coating one hardness of rotor surface, just can obtain enough desertification stone mills and decrease and anti-cavitation erosion ability.

By making the first surface film contain 50 to 90 weight percents, the preferably Cr of 70 to 90 weight percents ₃C ₂Or WC, this first surface film has splendid corrosion resistance and desertification stone abrasiveness.More particularly, contain chromium carbide or tungsten carbide and at least a metallic surface film of from Ni, Cr and Co, selecting, according to Cr ₃C ₂Or the difference of the content of WC can change to some extent.If Cr ₃C ₂Or the WC content increase, the hardness of skin covering of the surface also can increase thereupon, and still, toughness descends, and can become fragile, thereby causes it to ftracture or to peel off, and then has reduced reliability.If Cr ₃C ₂Or the content of WC remains in 50 to the 90 weight percent scopes, and this skin covering of the surface can keep enough desertification stone mills to decrease hardness and roughness so.Have again, in this scope, this skin covering of the surface tool one Hv1000 or higher hardness, so it can have fabulous anticorrosive and desertification stone abrasiveness.Have again, if sandstone density is higher, just must increase Cr ₃C ₂Or the content of WC is to improve the hardness of skin covering of the surface.In the case, Cr ₃C ₂Or the content of WC preferably accounts for 70 to 90 weight percents.

By giving the thickness of first surface film one 0.1 to 1.0mm, just can guarantee that rotor has enough life-spans and resists the sandstone wearing and tearing and cavitate, simultaneously, output and energy conservation also are gratifying.More particularly, because the tiny cave of some is arranged on the flame spraying film, so its thickness is necessary for 0.1mm or thicker, to embody splendid anticorrosive and abrasion resistance.On the other hand, along with the increase of flame spraying film thickness, its internal stress also increases thereupon, so that has reduced adhesive quality.On the tack this point, the flame-spraying film can only be thick or thinner for 1.0mm.Have, consider that from the antiwear property aspect of skin covering of the surface thickness 1.0mm just can guarantee the sufficiently long life-span, for the consideration that reduces workload and energy savings, thickness is preferably 1.0mm or thinner.From above-described discussion, can draw, thickness 0.1 to 1.0mm just can make rotor have sufficiently long life-span opposing sandstone wearing and tearing and cavitation erosion, and simultaneously, productivity ratio and energy conservation also are gratifying.

By with the method for flame spraying as the coated surfaces film, just can apply with comparalive ease and have one and can guarantee to resist the skin covering of the surface in the sufficiently long life-span of sandstone wearing and tearing and cavitation erosion.By with the method for flame spraying as skin covering of the surface coating, more particularly, the desirable thickness of the skin covering of the surface of being made up of Ni, Cr or Co and chromium carbide 0.1 is to 1.0mm, and the desirable thickness of the skin covering of the surface of being made up of Ni, Cr or Co and Tungsten carbite 0.1 is to 0.5mm.Therefore, by form this skin covering of the surface with flame spraying, just can apply with comparalive ease the skin covering of the surface with thickness like this, this thickness can be guaranteed the sufficiently long life-span of opposing sandstone wearing and tearing and cavitation erosion.

After coating the first surface film; by at 350 to 650 ℃; preferably heated 1 to 30 hour under 400 to 650 ℃ of temperature; in the skin covering of the surface of forming by chromium carbide or Tungsten carbite and Ni, Cr or Co the metal of Ni, Cr or Co mutually and the adhesion between chromium carbide particulate or Tungsten carbite particulate increase; thereby cause the hardness of skin covering of the surface to increase; correspondingly, the desertification stone mill decreases ability and the also raising thereupon of anti-cavitation erosion ability.Have, the adhesion of the boundary between skin covering of the surface and the parent metal increases, thereby has suppressed peeling off of skin covering of the surface again.As a result, skin covering of the surface peel off and disengaging is suppressed, thereby improved reliability, even be subjected to one also like this after impacting cracking when skin covering of the surface.Under high heating-up temperature; adhesion between the metal of the Ni in the skin covering of the surface, Cr or Co and chromium carbide particulate or Tungsten carbite particulate increases; and the adhesion increase of the boundary between skin covering of the surface and parent metal is faster; but, produced a kind of thermal strain because thermal expansion coefficient is different between skin covering of the surface and parent metal.Consider the impact of thermal strain his-and-hers watches facial mask, preferably making heating-up temperature is 650 ℃ or lower.Have, for the consideration to the skin covering of the surface formation speed, 350 ℃ of temperature are minimums again, will make coating process need long time if hang down again, so that be difficult in industrial application.For the consideration of practicability, best temperature range is 400 to 650 ℃.When 350 to 650 ℃ of temperature ranges were tested, heat treated need carried out under 350 ℃ 20 hours and carry out 1 hour under 650 ℃ of maximum temperatures.When testing in 400 to 650 ℃ of temperature ranges, this heat treated is tending towards 30 hours.Therefore, for the consideration to effect and energy conservation, should be 1 to 30 hours best heat time heating time.

If adopt the especially quick flame spraying of flame spraying as the method for coating first surface film, can form a uniform and fine and close skin covering of the surface at a three-dimensional structure so.Flame spraying has diverse ways, use according to they pluses and minuses separately.The flame spraying that can form a finest and close skin covering of the surface is the vacuum flame spraying, and the plasma torch coating is carried out in a vacuum in the method.But according to this vacuum flame coating process, pending member must be put into a vacuum chamber that is used to apply processing, so it in the present embodiment, and it is unpractical being applied to pumping element.Illustrate the method that another kind can apply a fine and close skin covering of the surface with a kind of explosive flame coating process and a kind of quick flame coating process.The explosive flame coating process just can cover a wider applicator surface in once spraying, so it is suitable for covering a large-sized flat member.But flame spraying gun and equipment size are bigger, thereby apply equably a three-dimensional dimension member such as rotor or shell so that detonation flame spraying is difficult to quality.Flame spraying can form the skin covering of the surface of a densification fast, and available one less relatively spray gun, so it can form a fine and close skin covering of the surface on the three-dimensional dimension member.

When the rotor surface coating one that is coated with the first surface film contained the second surface film of at least a material of selecting from the group that ebonite, epoxy resin, polyethylene and polyester are formed, the desertification stone abrasiveness and the cavitation resistance of whole member were increased sharply.As mentioned above, flame spraying is used the rifle of a less fast, and can form the uniform skin covering of the surface of a quality at a three-dimensional dimension member, still, finds that still it is difficult to some part at pump, such as the channel interior of rotor, forms gratifying skin covering of the surface.But, with contain chromium carbide, Tungsten carbite, nickel, chromium and cobalt and form the first surface film of at least a material of selecting in the group and compare, contain the second surface film of forming at least a material of selecting the group from ebonite, epoxy resin, poly-second combustion and polyester in desertification stone mill damage with resist aspect the cavitation erosion relatively poor.By selecting processing method rightly, even also can be coated with the satisfied skin covering of the surface of last layer such as positions such as rotor channel inside.Therefore, by flame coating by skin covering of the surface that chromium carbide or Tungsten carbite and Ni, Cr or Co constituted, and coating is by containing the skin covering of the surface that resin constituted at least a in ebonite, epoxy resin, polyethylene and the polyester, the desertification stone mill of member decreases and cavitation resistance, the raising of highly significant has been arranged on the whole.

After the rotor surface that scribbles the first surface film is coated the second surface film again, parent metal is that the part has been coated with the first and second overlapping skins covering of the surface at least, so, the desertification stone mill decreases and resists the reliability of cavitation erosion ability and desertification stone mill damage and anti-cavitation erosion just to improve.The breakage of skin covering of the surface and peel off often begins from the end of skin covering of the surface.The skin covering of the surface that at least a metal consists of in by chromium carbide or tungsten carbide and Ni, Cr or Co is coated by resin with a part of overlap mode, such as hard rubber, epoxy resin, polyethylene or polyester, behind the skin covering of the surface that consists of, parent metal is not had ground, any slit parcel, thereby the ability of its opposing sandstone wearing and tearing and cavitation erosion is improved.

Fig. 1 is the sectional view of the horizontal pump of one embodiment of the invention;

Fig. 2 is the perspective schematic view of the pump rotor (impeller) of the embodiment of the invention;

Fig. 3 is the longitudinal section of the pump rotor of the embodiment of the invention;

Fig. 4 is the front elevation of the pump rotor of the embodiment of the invention, and wherein a part is broken away;

Fig. 5 is the amplification view of the pump rotor of the embodiment of the invention;

Fig. 6 is the amplification view of the pump casing of the embodiment of the invention;

Fig. 7 is the amplification sketch of the processed pump surface portion of this embodiment of the invention;

Fig. 8 is the amplification sketch of the processed pump surface portion of another embodiment of the present invention;

Fig. 9 is the detailed enlarged view of processed pump surface portion shown in Figure 8;

Figure 10 is the amplification sketch of the processed pump surface portion of another embodiment of the present invention;

Figure 11 is the amplification sketch of the processed pump surface portion of another embodiment of the present invention;

Figure 12 is the flow chart of manufacture method of the pump rotor of one embodiment of the invention;

Figure 13 is the flow chart of manufacture method of the pump rotor of another embodiment of the present invention;

Figure 14 is the flow chart of manufacture method of the pump rotor of another embodiment of the present invention;

Figure 15 has provided surface-treated sandstone abrasion detection result disclosed in this invention;

Figure 16 is the sectional view of the horizontal pump of another embodiment of the present invention;

Figure 17 is the perspective schematic view of the pump rotor of the embodiment of the invention, and its part is broken away;

Figure 18 is the longitudinal section of the pump rotor of the embodiment of the invention;

Figure 19 is the perspective schematic view of the pump rotor of the embodiment of the invention, and its part is broken away;

Figure 20 is the amplification view of the pump rotor of the embodiment of the invention;

Figure 21 is the amplification view of the pump casing of the embodiment of the invention;

Figure 22 is the flow chart of manufacture method of the pump rotor of another embodiment of the present invention;

Figure 23 is the perspective schematic view of the water turbine of the embodiment of the invention, and its part is broken away;

Figure 24 is the perspective schematic view of the turbine impeller (rotor) of the embodiment of the invention;

Figure 25 is the amplification view of the turbine impeller of the embodiment of the invention;

Figure 26 is the flow chart of manufacture method of the turbine impeller of another embodiment of the present invention;

Figure 27 is the perspective view of the water turbine guide vane of the embodiment of the invention;

Figure 28 is vertical perspective section view of the vertical pump of another embodiment of the present invention;

Figure 29 is vertical perspective section view of the vertical pump blade of the embodiment of the invention;

Fig. 1 is a schematic cross sectional views of implementing horizontal pump 1 of the present invention.One rotor 2 is fixed on one 4, and this two end supports of 4 is on bearing 3.Rotor 2 is rotated by a main tumbler (not shown) that links to each other with axle 4 one ends, so that this rotor 2 is discharged from shell 5 from its two ends suction.

The parts that the present invention was applied to are rotor 2 and shell 5.Now, will be example with rotor 2, describe the present invention in detail.Fig. 2 shows the inside of rotor 2 briefly.This rotor 2 comprises the axle sleeve 21, the cover cap 23 and the blade 22 that links to each other with axle sleeve 21 and cover cap 23 around this axle sleeve 21 that are contained on the axle 4.Define a passage at

axle sleeve

21 and 23 of cover caps, water sucks from the suction port 24 of both sides, and is quickened by rotor rotated 2, then discharge from exhaust port 25, and then the passage on shell 5 flows out this pump.

When containing the more grains of sand in the water of stream in the rotor 2, rotor 2 is worn and torn by the impinging particle in the grains of sand.The quartz-grain period of the day from 11 p.m. to 1 a.m that contains high rigidity in the grains of sand, this sand erosion especially become serious.When grains of sand concentration surpasses 2kg/m ³, and flow velocity can cause a kind of extremely serious sand erosion when surpassing 30m/s.For preventing the wearing and tearing of this grains of sand, rotor 2 except with part that axle 4 matches, it is 0.1 to 0.3mm Ni alloy plating film that remaining part is all coated a thickness.This Ni alloy plating film contains the P of 3% weight percent and the B of 1% weight percent.The part that rotor 2 is higher at water flow velocity or the particle impacting frequency is bigger, the part of blade 22 and cover cap 23 just also scribbles thickness and is 0.4 to 0.6mm Cr in addition ₃C ₂The flame coated film 6 of the Cr of the Ni-4% weight percent of-16% weight percent (is also referred to as " Cr ₃C ₂The coating film of-20%NiCr ").In the present embodiment, the material of rotor 2 is the cast steel (being also referred to as " 13%Cr cast steel ") that contains 13% chromium.Parent metal or 13%Cr cast steel have the Vickers hardness of an about Hv200 to 250; The Vickers hardness of Ni alloy plated layer is 400 to 500; Cr ₃C ₂The Vickers hardness of-20%NiCr flame coated film is about 800 to 900.

In Fig. 2, scribble Cr ₃C ₂The part of-20%NiCr is equipped with hacures.Blade 22 scribbles Cr ₃C ₂-20%NiCr flame coated film, these flame coated film are in outlet 22a and suction part 22b (although not shown in Fig. 2) locates.Cover cap 23 flames are coated with Cr ₃C ₂-20%NiCr film, these are filmed and are in outlet 23a and a suction part 23b place.This Cr ₃C ₂-20%NiCr film covers on the Ni alloy plating film so that a kind of double-decker to be provided, and the upper strata is Cr ₃C ₂-20%NiCr flame coated film, lower floor is Ni alloy plating film.

The outlet 23a place of cover cap 23, the flow velocity of water is higher, and for the consideration that prevents serious sand erosion, the cover cap that surpasses 30m/s at water flow velocity exports also flame coating Cr of 23a place ₃C ₂-20%NiCr film.

Fig. 3 is the sectional side elevation of rotor 2 shown in Figure 2, and Fig. 3 is a width of cloth cutaway view, scribbles Cr ₃C ₂The part of-20%NiCr is equipped with hacures.These scribble Cr with the flame coating process ₃C ₂The part of-20%NiCr is in the suction part 22b place of outlet 23a and blade 22, and these parts are easy to be applied by flame, therefore can form a high-quality skin covering of the surface.

Fig. 4 is look the from the side front elevation of gained of rotor 2 shown in Figure 3.Among the figure, for making its internal structure clear, a side of cover cap 23 is deleted.In Fig. 4, to similar shown in Fig. 3, scribble Cr ₃C ₂The part of-20%NiCr is equipped with hacures.At suction inlet, blade 22 is in an acute angle with axle sleeve 21, and more more becomes a right angle near outlet.Therefore, this blade is easy to the flame coating in the suction side, but in the then difficult coating of axle sleeve one side.As a result, the flame of the suction inlet of blade 22 coating part 22b nearly all is in and sucks a side overleaf or axle sleeve one side does not then almost have.

Fig. 5 is vertical amplification view of exhaust port of the blade 22 of rotor 2.Blade 22 all scribbles a Ni alloy plating film 7, and part scribbles Cr ₃C ₂-20%NiCr film 6.In this two membranes, Ni alloy plating film 7 is in lower floor, Cr ₃C ₂-20%NiCr film 6 is located thereon.

Fig. 6 be shell 5 in the face of part 5a, promptly over against vertical amplification view of the part of rotor exhaust port 25.This outlet 25 in the face of part 25a place, flow velocity is higher, the collision frequency of particulate is also higher, weares and teares so sandstone more may take place.Therefore, all be coated with Ni alloy plating film 7 on the inner surface of shell 5, the water that flows out from rotor outlet 25 directly impact in the face of then not only scribbling Ni alloy plating film 7 on the part 5a but also scribble Cr ₃C ₂-20%NiCr flame coated film 6.Shell 5 be separated two halves in a front one side of something, namely vertical row exports half of 25 separating planes, can be applied by flame, remaining one side of something does not then have enough spaces to coat a satisfied flame coated surfaces film.Therefore, the later half limit is the same with rotor 2, only scribbles Ni alloy plating film 7.Fig. 7 is a width of cloth sketch, the figure shows Cr ₃C ₂The cross-section structure of-20%NiCr flame coated film 6 and Ni alloy plating film 7 overlaids part.By the following heat treatment that will describe, Cr ₃C ₂NiCr in the-20%NiCr flame coated film 6 diffuses into Ni alloy plating film 7, thereby forms a diffusion layer 6d.Equally, Ni alloy plating film 7 also diffuses into parent metal and forms a diffusion layer 7d.By these two diffusion layers of formation like this, Cr ₃C ₂-20%NiCr flame coated film 6 and Ni alloy plating film 7 are attached on the parent metal securely, thereby have prevented any cracking or peel off/generation of segregation phenomenon.

In embodiment described above, with Cr ₃C ₂-20%NiCr film is as the example of flame coated surfaces film, and with the example of Ni-3 weight percent P-1 weight percent B alloy plating film as Ni alloy plating film, still, the present invention is not limited to the above-mentioned concrete composition of lifting.The WC-Co skin covering of the surface or the WC-NiCr skin covering of the surface that will contain 50% to 90% weight percent WC also can reach same effect as the flame coated film.Same Ni alloy plating film also is not limited to the B alloy plating film of the P-1 weight percent of Ni-3 weight percent.The Ni alloy that contains the B of the P of the B of the P of 1 to 10 weight percent or 0.5 to 5 weight percent or 1 to 10 weight percent and 0.5 to 5 weight percent also can reach same effect.

Fig. 8 is a width of cloth sketch, the figure shows the Cr of another embodiment pump rotor ₃C ₂The cross-section structure of-20%NiCr flame coated film 6 and the Ni alloy plating film 71 overlaids part that contains trickle SiC particle.In this embodiment, rotor material still is a 13%Cr cast steel.The Vickers hardness of parent metal or 13%Cr cast steel is about 200 to 250; The Vickers hardness that contains the Ni alloy plating film of trickle SiC particle is about 500 to 800; Cr ₃C ₂The Vickers hardness of-20%NiCr flame coated film is about 800 to 900.Herein, the Ni alloy plating film that contains trickle SiC particle includes the SiC particulate of 7% weight percent, and these microparticulate therein.In the present embodiment, also be by heat treatment, Cr ₃C ₂NiCr in the-20%NiCr flame coated film 6 diffuses into the Ni alloy plating film 7 that contains trickle SiC particle, thereby forms a diffusion layer 6d, and the Ni alloy plating film 7 that contains trickle SiC particle also diffuses into parent metal and forms a diffusion layer 7d.By these two diffusion layers of formation like this, Cr ₃C ₂-20%NiCr flame coated film 6 and the Ni alloy plating film 7 that contains trickle SiC particle are attached on the parent metal securely, thereby have prevented any cracking or peel off/generation of segregation phenomenon.

In the present embodiment, can reach following effect by heat treatment.Fig. 9 is a width of cloth sketch, the figure shows Cr ₃C ₂The amplification profile structure of-20%NiCr flame coated film and the Ni alloy plating film overlaid part that contains trickle SiC particle.It is the trickle SiC particle of 7% weight percent that icon 7e represents content, and its diameter is several to dozens of microns.By following heat treatment, the engaging force that trickle SiC particle and Ni-P electroplate between the base layer is increased, thereby has improved hardness, toughness and the antiwear property of skin covering of the surface.

In the aforementioned embodiment, the fine particle of the dispersion of explanation is not limited in SiC as an example of SiC example, for example can also be Si ₃N ₄, SiO ₂, AL ₂O ₃Or ZrO ₃Content is not different with changes in material, but when the percentage by volume of content is 5, can demonstrate remarkable effect, and when percentage by volume content surpasses 10%, skin covering of the surface is become fragile, so that reduces surperficial film strength.Therefore, percentage by volume content preferably is in 5 to the 1O% scopes.

1O and 11 describes another embodiment below with reference to accompanying drawings.Figure 10 is a width of cloth sketch, the figure shows the cross-section structure of the WC-27%NiCr flame coated film 61 and the boride layer 72 overlaids part of another embodiment's pump rotor.In the present embodiment, the rotor metal still is a 13%Cr cast steel.The Vickers hardness of parent metal or 13%Cr cast steel is about 200; The Vickers hardness of boride layer 72 is about 700 to 800; The Vickers hardness of WC-27%NiCr flame coated film 61 is about 900 to 1100.

In the present embodiment, except the part that matches with axle, the remaining surface of rotor is all accepted a boronising and is processed, to form a boride layer.After this, with on the same section shown in Fig. 2 apply WC-27%NiCr flame coated film 61.Boride layer is a hard layer, and wherein, boron diffuses in the parent metal from outer surface, to separate out trickle and hard boronation phase, for example can be FeB, Fe in this enforcement ₂B or CrB.Therefore, make this solid bed particularly splendid, simultaneously, also very outstanding aspect resistance to wearing in the adhesive quality of adhering to aspect the parent metal with about 700 to 800 Vickers hardnesses.Have again, on channel inner surface, also can be formed with diffusion phase.In addition, the Vickers hardness of WC-27%NiCr flame coated film 61 is about 900 to 1100, so it has fabulous resistance to wearing and corrosion resistance.Behind two skins covering of the surface, rotor can have a splendid abrasion resistance on the whole.

In the present embodiment, equally by heat treatment, the NiCr in the WC-27%NiCr flame coated film 61 diffuses into boride layer 72 and forms diffusion layer 6d, thereby has strengthened adhesive quality.The raising of this tack aspect just can prevent any cracking of skin covering of the surface or peel off/generation of segregation phenomenon.

Figure 11 is a width of cloth sketch, the figure shows the cross-section structure of the WC-27%NiCr flame coated film 61 and the chromising layer 73 overlaid part of another embodiment's pump rotor.In the present embodiment, the rotor metal is example for 13%Cr cast steel still.The Vickers hardness of parent metal or 13%Cr cast steel is about 200; The Vickers hardness of chromising layer 73 is about 700 to 800; The Vickers hardness of WC-27%NiCr flame coated film 61 is about 900 to 1100.

In the present embodiment, except the part that matches with axle, the remaining surface of rotor is all accepted a chromising and is processed, to form a Chromizing Layer.After this, with on the same section shown in Fig. 2 apply WC-27%NiCr flame coated film 61.Chromizing Layer is a hard layer, and wherein, chromium diffuses in the parent metal from outer surface, to separate out trickle and hard chromaking phase, for example can be Fe-Cr, Cr in the present embodiment ₇C ₃Or Cr ₂₃C ₆Therefore, make this solid bed splendid, simultaneously, also very outstanding aspect resistance to wearing in the adhesive quality of adhering to aspect the parent metal with about 700 to 800 Vickers hardnesses.Have again, on channel inner surface, also can be formed with diffusion phase.In the present embodiment, equally by heat treatment, the NiCr in the WC-27%NiCr flame coated film 61 diffuses into chromising layer 73 and forms diffusion layer 6d, thereby has strengthened adhesive quality.The raising of this tack aspect just can prevent any cracking of skin covering of the surface or peel off/generation of segregation phenomenon.

Below with reference to accompanying drawings 12, be example with the rotor shown in Fig. 22, an embodiment of manufacture method of the present invention is described.This rotor 2 is prepared by casting method.After casting, this rotor 2 is accepted a stress relief annealing and is processed, and then is reprocessed into preliminary dimension.As a pretreatment process of electroplating, to remove the oil film and the patina of rotor surface earlier.Next, by the electrodeless plating method remaining surface of rotor except the part that matches with axle all electroplated upper Ni alloy plating film 7.After having carried out this plating, will need to apply again Cr ₃C ₂The part of-20%NiCr film is carried out preliminary treatment.Elder generation's rotor washing carries out blasting treatment to form a suitable surface roughness with alumina powder then with except degrease and oil stain.Behind these job dones, apply Cr with a quick flame spraying at the predetermined portions of rotor ₃C ₂-20%NiCr flame coated film 6.In the present embodiment, to be coated with dusting be by pulverizing and screening contains Cr to flame ₃C ₂The sintered body of-20%NiCr composition prepares.Herein, the flame coating process is that all are suitable for applying a said three-dimensional body fast, as the best way in the method for rotor, because it can form a dense film, and its flame spraying rifle is less relatively, can form a homogeneous and fine and close film on the narrow and small relatively member in a space.After finishing the flame spraying operation, whole rotor continues 5 to 30 hours heat treatment in 500 to 600 ℃ of environment.In the present embodiment, rotor kept 15 hours down at 550 ℃, cooled off with stove then.By this heat treatment, at Cr ₃C ₂Ni, Cr and Cr in-the 20%NiCr flame coated film 6 ₃C ₂Between adhesive force increase, thereby improved the hardness of skin covering of the surface, improved correspondingly that the desertification stone mill decreases and the ability of anti-cavitation erosion.Cr is arranged again ₃C ₂-20%NiCr flame coated film 6 increases with the adhesive force of the boundary of parent metal, thereby has suppressed peeling off of skin covering of the surface.Therefore, peeling off with separating of skin covering of the surface is suppressed, thereby increased the reliability of skin covering of the surface, namely box lunch its be subjected to one and impact and during cracking, also like this.Herein, this phenomenon is not only at Cr ₃C ₂Take place in-20%NiCr flame the coated film 6 and in WC-NiCr skin covering of the surface and WC-Co skin covering of the surface.Have, by this heat treatment, Ni alloy plating film 7 diffuses to form a very strong adhesion mutually with parent metal again.So Ni alloy plating film 7 obtains an adhesion that strengthens to suppress peeling off of skin covering of the surface at the boundary of itself and parent metal.

Under higher heat treatment temperature, Cr ₃C ₂Metal Phase and the Cr of Ni and Cr in-the 20%NiCr flame coated film 6 ₃C ₂Adhesive force between particulate increases, and the adhesive force of skin covering of the surface and parent metal boundary then increases faster, still, and Cr ₃C ₂Produce a thermal strain between-20%NiCr flame coated film 6 and parent metal or 13Cr steel owing to thermal coefficient of expansion is different.Consider the influence of thermal strain to skin covering of the surface, heating-up temperature is preferably lower than 600 ℃.Draw after temperature in 500 to 600 ℃ of scopes tested, the shortest need of heat treated carried out 5 hours, but less than 30 hours.Therefore, for the consideration of effect and energy saving, be 5 to 30 hours best heat time heating time.This situation is not only applicable to Cr ₃C ₂-20%NiCr flame coated film is if its WC content in 50 to 90 weight percent scopes, also is applicable to WC-NiCr skin covering of the surface and WC-Co skin covering of the surface.

Below with reference to accompanying drawings 13, be example with the rotor shown in Figure 10 2, another embodiment of manufacture method of the present invention is described.This rotor 2 is prepared by casting method.After casting, the work of being processed into reservation shape is identical with last embodiment's.As the pretreatment process of a boronising, to remove earlier oil film and the oxide-film of rotor surface.Next, all the other whole surfaces that a kind of thin pulp of boron diffusion powder spread upon rotor except that the part that matches with axle.Behind its airing, rotor is kept a scheduled time under a predetermined temperature, to form a boride layer.In the present embodiment, rotor kept 10 to 20 hours under 800 to 950 ℃ of temperature, then annealed in a stove.Behind a sufficiently long cooling stage, remove the residual thin pulp on the rotor surface, and before the flame coating, accept a preliminary treatment.With aluminium powder rotor is carried out sand blast to form a proper surface roughness.Behind these job dones, apply WC-27%NiCr flame coated film 61 with a quick flame spraying at the predetermined portions of rotor.In the present embodiment, to be coated with dusting be to prepare by the sintered body of pulverizing and screening contains the WC-27%NiCr composition to flame.After finishing the flame spraying operation, whole rotor continues 5 to 30 hours heat treatment in 500 to 600 ℃ of environment.In the present embodiment, rotor kept 15 hours down at 550 ℃, cooled off with stove then.By this heat treatment, the adhesive force in WC-27%NiCr flame coated film 61 between Ni, Cr and WC particle increases, thereby has improved the hardness of skin covering of the surface, has correspondingly improved the ability of desertification stone mill damage and anti-cavitation erosion.Have, WC-27%NiCr flame coated film 61 increases with the adhesion of the boundary of parent metal, thereby has suppressed peeling off of skin covering of the surface again.These measures have produced identical effect on abrasion resistance.

Figure 14 illustrates the manufacture method of rotor shown in Figure 11.Outside the dechromisation method of diffusion, this method is basic identical with last method.

In the method, adopted several element in the method that forms a diffusion layer another kind of Elements Diffusion being entered the top layer.The element that in this method, adopts, also can enumerate multiple element, such as aluminium, vanadium, niobium and titanium.But the just desertification stone mill damage of the element that adopts and corrosion resistance and expense consideration, the present invention form the large-size components that the method for boride layer or Chromizing Layer is suitable for using most in water, such as pumping element.On the other hand, method of diffusion for example can be to form one to electroplate mutually and the galvanoplastic of heating or the molten-salt growth method of dipping in a fused salt.But, consider that Scantlings is big and channel interior is complex-shaped, so the present invention's powder diffusion method is the most appropriate.This Powder Diffusion comprises and the similar thin pulp semar technique of last embodiment and method that member is embedded in the powder and is heated that still, the present invention can adopt other two kinds of methods.In these methods, the thin pulp coating process is the best approach, is like this when especially considering the processing of channel interior.

To describe below the desertification stone mill and decrease the result who detects, the purpose of carrying out this detection is to confirm effect of the present invention.In these detected, the sample of the 13%Cr cast steel of processing by treatment process disclosed by the invention was by in the water that it is immersed the aluminiferous powder and spray a high-speed water jet from a nozzle near its setting to it and check its degree of wear.This detecting method is taken passages in table 1.If imagination is common river, the 30g/l density in the testing conditions has been quite high, and in fact this situation can not exist in river.This value is much larger than the 2Kg/m that can show effect of the present invention ³Sandstone density, this value only is used in the accelerated test.

Table 1: sandstone abrasion detection condition

Used sandstone	Alumina powder
Used sandstone	Alumina powder	Sandstone density	30 (g/l)
Jet velocity	40 (m/s)	Sandstone density	30 (g/l)
Jet velocity	40 (m/s)	The projected angle of impact of jet	45 degree
Distance between nozzle and sample	10mm	The projected angle of impact of jet	45 degree
Distance between nozzle and sample	10mm	Detection time	1 hour

In table 15, enumerated the result of this test.Examined sample is the 13%Cr cast steel that is coated with skin covering of the surface of the present invention.Detected the weight that reduce front and back in 1 hour by measuring, and come by wearing and tearing percentaeg assessment wear intensity with the weight of removing this minimizing detection time.Figure 15 shows the value of the wear intensity of relative one 100% the 13%Cr material that is not subject to processing.Boride layer disclosed by the invention, chromising layer, the Ni-P-B electroplating film that contains the SiC particulate all are inferior to the flame coated film aspect resistance to wearing, still, wearing and tearing percentaeg itself will this not be subject to processing the low of material, and maximum can hang down 18%.Cr is arranged again ₃C ₂-20%NiCr flame coated film and WC-27%NiCr flame coated film are very outstanding aspect resistance to wearing, and the wearing and tearing percentage is low to about ten Percent.Therefore, in the present invention, and be coated with aforementioned flame coated film on the higher zone of the contacted zone of high-velocity fluid or single particle frequency of impact, then scribble another kind of skin covering of the surface on the low-speed region, very effective to the reliability that improves whole pump.

Figure 16 is a schematic cross sectional view of implementing horizontal pump 101 of the present invention.One rotor 102 is packed on one 104, and these axle 104 two end supports are on bearing 103.Rotor 102 is rotated by a main tumbler (not shown) that links to each other with axle 104 1 ends, so that this rotor 102 is from its two ends suction, and discharges from shell 105.

The parts that the present invention was applied to are rotor 102 and shell 105.Now, will be example with rotor 102, describe the present invention in detail.Figure 17 shows the inside of rotor 102 briefly.As shown in the figure, for make internal structure clear for the purpose of, its part is separated.This rotor 102 comprises the axle sleeve 121, the cover cap 122 and the blade 123 that links to each other with axle sleeve 121 and cover cap 122 around this axle sleeve 121 that are contained on the axle 104.Define a passage at

axle sleeve

121 and 122 of cover caps, water sucks from the suction port 124 of both sides, and rotor 102 acceleration that are rotated, and then discharge from exhaust port 125, and then the passage on shell 105 flows out this pump.

When containing the more grains of sand in the water of stream in the rotor 102, rotor 102 can be worn and torn by the impinging particle in the grains of sand.The quartz-grain period of the day from 11 p.m. to 1 a.m that contains high rigidity in the grains of sand, this sand erosion especially become serious.Rotor 102 is at itself and high-velocity flow or the higher position of particle hits frequency, and just the part of blade 123 and cover cap 122 also scribbles a Cr in addition ₃C ₂The Cr of the Ni-4 weight percent of-16 weight percents and thickness are that 0.4 to 0.6mm flame coated film (is also referred to as " Cr ₃C ₂-20%NiCr spraying and applying film ").Rotor 102 except with part that axle 104 cooperates remaining surface all to be coated with in addition a thickness be 1 to 2mm epoxy resin surface film.In the present embodiment, in this epoxy resin surface film, be dispersed with the alumina particulate of 50% weight percent.This epoxy resin surface film also covers simultaneously and scribbles Cr ₃C ₂The part of-20%NiCr flame coated film.This lap provides a kind of double-decker, and lower floor is Cr ₃C ₂-20%NiCr flame coated film 108, upper strata are the epoxy resin surface film.

Figure 18 is the A-A longitudinal section that cuts open the rotor of getting shown in Figure 2 102 along direction a.Figure 18 is a width of cloth profile, scribbles Cr among the figure ₃C ₂The part of-20%NiCr flame coated film 108 is equipped with hacures.These scribble Cr ₃C ₂The part of-20%NiCr flame coated film 108 be positioned at suction inlet 124 and outlet 125 near, these parts are easy to flame coating.

Figure 19 is the external view along the rotor shown in Figure 17 2 of direction b gained.Among the figure, for make internal structure clear for the purpose of, cover cap 122 right one side of something are left out.In Figure 19, similar with Figure 18, scribble Cr ₃C ₂The part of-20%NiCr flame coated film 108 is equipped with hacures.

Figure 20 be B-B along direction c intercepting to amplifying longitudinal section, the figure shows the part of rotor 102 shown in Figure 19.Cover cap 122 and blade 123 parts scribble Cr ₃C ₂-20%NiCr flame coated film 108, but whole surface all is coated with epoxy resin surface film 109.Form epoxy resin surface film 109 and the Cr of lower floor ₃C ₂-20%NiCr flame coated film 108 is overlapping.

Figure 21 is the amplification longitudinal section of shell 105 at the place, front portion of exhaust port 125.At 151 places, front portion of exhaust port 125, rate of flow of fluid is higher, and the particle collisions frequency is also higher, and therefore the sandstone wearing and tearing may take place.So, this part, the part that the current that namely flow out from outlet 125 directly impact scribbles Cr ₃C ₂-20%NiCr flame coated film 108, the whole cover ring epoxy resins of inner surface skin covering of the surface 109.The two halves of shell 105 are separated, the forward part 151 of exhaust port 125, and promptly the part of vertical parting plane can be applied by flame, and remaining part is because the space can not be coated a gratifying flame coated film inadequately.Therefore, latter half and the rotor 102 the same epoxy resin surface films 109 that only are coated with.

22 is the embodiment that example is described manufacture method of the present invention with rotor 102 below with reference to accompanying drawings.Rotor 102 is prepared by casting method.Material therefor is a 13%Cr cast steel.After casting, this rotor 102 is accepted a stress relief annealing technology, then is reprocessed into preliminary dimension.Next, will need to apply Cr ₃C ₂The part of-20%NiCr film is carried out preliminary treatment.Elder generation's rotor washing carries out blasting treatment to form a suitable surface roughness with alumina powder then with except degrease and oil stain, and oxide-film or similar film just are removed to form a new surface like this.Behind these job dones, apply Cr with a quick flame spraying at the predetermined portions of rotor ₃C ₂-20%NiCr flame coated film 108.In the present embodiment, to be coated with dusting be by pulverizing and screening contains Cr to flame ₃C ₂The sintered body of-20%NiCr composition prepares.Herein, the flame coating process is that all are suitable for applying a said three-dimensional body fast, as the best method in the method for rotor, because it can form a dense film, and its flame spraying rifle is less relatively, can form the even and fine and close film of a quality on the narrow and small relatively member in a space.

After finishing the flame spraying operation, rotor is put into a stove, and, preferably continue 1 to 30 hour heat treatment in 400 to 650 ℃ of temperature ranges at 350 to 650 ℃.In the present embodiment, rotor kept 15 hours down at 550 ℃, cooled off with stove then.Rotor is larger-size parts, so it is difficult to by Fast Heating or cooling, and Fast Heating or cooling can cause producing in the skin covering of the surface unsuitable thermal stress.Therefore, rotor kept 15 hours in stove under 550 ℃, then with the stove Slow cooling.

By under this temperature, heating, at Cr ₃C ₂Ni, Cr and Cr in-the 20%NiCr flame coated film 108 ₃C ₂Between adhesive force increase, thereby improved the hardness of skin covering of the surface, improved correspondingly that the desertification stone mill decreases and the ability of anti-cavitation erosion.Cr is arranged again ₃C ₂-20%NiCr flame coated film 108 increases with the adhesive force of the boundary of parent metal, thereby has suppressed peeling off of skin covering of the surface.As a result, peeling off with separating of skin covering of the surface is suppressed, thereby increased the reliability of skin covering of the surface, namely box lunch its be subjected to one and impact and during cracking, also like this.Herein, this phenomenon is not only at Cr ₃C ₂Take place in-20%NiCr flame the coated film 108 and in WC-NiCr skin covering of the surface and WC-Co skin covering of the surface, also can take place.

Under higher heat treatment temperature, the burst size of the residual stress of welding portion increases, the Metal Phase of Ni and Cr and Cr in the skin covering of the surface ₃C ₂Adhesive force between particulate increases, and the adhesive force of skin covering of the surface and parent metal boundary then increases faster, still, and Cr ₃C ₂Produce a thermal stress between-20%NiCr flame coated film 108 and parent metal or 13Cr steel owing to thermal coefficient of expansion is different.Consider the influence of thermal stress to skin covering of the surface, heating-up temperature is preferably lower than 650 ℃, has again, for consideration to the skin covering of the surface formation speed, 350 ℃ of temperature are minimums, will make coating process need long time if hang down again, so that be difficult in industrial application.For the consideration of practicability, best temperature range is 400 to 650 ℃.Learning after 350 to 650 ℃ of temperature ranges are investigated at 350 ℃ needs 20 hours down, and carrying out heat treated under 650 ℃ then needs 1 hour at least.Draw after 400 to 650 ℃ of temperature ranges are tested, the time of heat treated was less than 30 hours.Therefore, for the consideration of effect and energy saving, be 1 to 30 hour best heat time heating time.This situation is not only applicable to Cr ₃C ₂-20%NiCr flame coated film is if its WC content in 50 to 90 weight percent scopes, also is applicable to WC-NiCr skin covering of the surface and WC-Co skin covering of the surface.

After an enough cooling, rotor 102 is all applied epoxy resin film 109 except the remaining surface in surface that cooperates with axle 102.In the present embodiment, used a kind of solvent, this solvent is to be that the curing agent of 10 to 40 microns aluminium oxide and 10% weight percent mixes with bifunctional epoxy resin and makes by the mean particle dia with 50% weight percent.This solvent be applied on rotor 102 except match with axle 104 the surface remaining surface on, be heated then, and be set under the predetermined condition, so that make its oven dry.

Figure 23 is the schematic external view of the water turbine 106 of another embodiment of the present invention, knows more that for making its internal structure its part is cut.In Figure 23, icon 141 is represented an axle; 107 represent impeller; 110 represent a guide vane; 111 represent one to go up impeller cover; 112 represent a following impeller cover; Reach 113 and represent a bearing.Water enters impeller 107 from guide vane 110, and this impeller 107 is contained on the axle 141, so the kinetic energy of water can make impeller 107 and axle 141 rotate, thereby drives the generator (not shown) rotation that links to each other with axle 141 1 ends, and then sends electric energy.

Implementing parts of the present invention is impeller 107, guide vane 110, last impeller cover 111 and following impeller cover 112.When containing the more grains of sand in the water that flows into impeller 107, the bump of the grains of sand causes impeller 107, guide vane 110, goes up impeller cover 111 and the 112 generation sandstone wearing and tearing of following impeller cover.For preventing the wearing and tearing of this sandstone, impeller 107, guide vane 110 and upper and lower lobes wheel cap 111,112 the part that water flow velocity is higher or the particle hits frequency is higher namely estimate to produce on the part that sandstone wear and tear applying Cr ₃C ₂-20%NiCr film, and be coated with a kind of 50% weight percent alumina particulate that contains in epoxy resin wherein at remainder.Cr ₃C ₂-20%NiCr film and epoxy resin surface film are mutually stacked, and the former is in lower floor, and the latter is in the upper strata.

To describe as an example of impeller 107 and guide vane 110 example the present invention in detail below.

Figure 24 is the perspective schematic view of impeller 107.In Figure 24, icon 171 is represented a top (bizet); 172 represent a band; 173 represent blade.Top 171 and blade 173, and be with 172 and blade 173 weld together, to form impeller 107.Figure 25 is the amplification profile of the welding portion of top 171 and 173 in blade.In Figure 25, for avoiding numerous and diverse, not only push up 171 and blade 173 do not beat hatching, welding portion is not beaten hatching yet.

In view of high flow velocity and a high collision frequency, blade 173 scribbles a Cr on its whole surface ₃C ₂-20%NiCr skin covering of the surface 108, top 171 and be with 172 also to scribble Cr on the surface within it ₃C ₂-20%NiCr skin covering of the surface 108.Epoxy resin surface film 109 not only is coated on the whole surface of impeller 107 but also is coated in and scribbles Cr ₃C ₂On the part of-20%NiCr skin covering of the surface 108.The impeller inner face is subjected to high speed water jet impact, therefore is preferably on its whole surface and is coated with Cr ₃C ₂-20%NiCr skin covering of the surface 108, still, top 171 and blade 173, and be with 172 and blade 173, can not apply in advance the flame coated film, because will being welded to each other, they form impeller 107.Therefore, welding portion will apply epoxy resin surface film 109 to form a kind of structure that prevents the sandstone wearing and tearing afterwards in welding.

26 is the embodiment that example is described a manufacture method of the present invention with impeller 107 below with reference to accompanying drawings.Figure 26 is the flow chart of manufacture method of the water turbine 107 of the embodiment of the invention.At first, prepare separately to push up 171, be with 172 and blade 173.Afterwards, with quick flame coating process the top 171, be with 172 and blade 173 on apply separately Cr ₃C ₂-20%NiCr skin covering of the surface.Be coated with Cr ₃C ₂During-20%NiCr skin covering of the surface, need to compare Cr with one ₃C ₂The metallic plate of-20%NiCr surface thickness twice or more times is applied on the part that will weld, to prevent that this part is by Cr ₃C ₂-20%NiCr skin covering of the surface covers.If this Cr of this metallic plate ₃C ₂-20%NiCr surface thickness twice or more times, it just can have the thermal resistance that enough opposing intensity and one is enough to resist the high-speed gas in the quick flame coating process so, prevents from rupturing and splashing with this.Have, when the thickness specific surface thickness twice of sheet metal or more times, the skin covering of the surface of shaded portions and coating part can not merge mutually, therefore can form satisfied skin covering of the surface end again.

Next, top 171 and blade 173 and be with 172 and blade 173 be welded to one another and form impeller 107 together.After having carried out this welding job, welding portion substantially is a suitable circle and concentrates with the stress in avoiding turning round.Then, impeller 107 is put into a stove, accept a destressing and process, in this was processed, impeller 107 preferably kept 1 to 30 hours in 400 to 650 ℃ of temperature ranges at 350 to 650 ℃.In the present embodiment, impeller 107 kept 15 hours down at 550 ℃, cooled off with stove then.Here, these 15 hours is the time that keeps down at 550 ℃.When 550 ℃ of lower heating, kept about 5 hours or the hardness of longer time skin covering of the surface will increase, keep about 10 hours tacks to be significantly improved.Impeller is a large-size components, and it is difficult to by rapid heating or cooling, and temperature variation is also improper fast from the thermal stress of skin covering of the surface.Therefore impeller after keeping 15 hours under 550 ℃ of temperature, cools off with stove in stove.After obtaining an enough cooling, remove the patina of circular weld part.

Behind these job dones, the remaining surface of impeller 107 except the face that matches with axle 141 all coated epoxy resin film.In the present embodiment, used a kind of solvent, this solvent is to be that the curing agent of 10 to 40 microns aluminium oxide and 10% weight percent mixes with bifunctional epoxy resin and makes by the mean particle dia with 50% weight percent.This solvent be applied on impeller 107 except with the fitting surface of axle 141 remaining surface on, be heated then, and be set under the predetermined condition, so that make its oven dry.

To describe guide vane 110 below, also, implement another parts of the present invention.Figure 27 is the external view of guide vane 110.This guide vane 110 is made up of a wheel shaft 201 and a blade-section 202, in Figure 27, scribbles Cr ₃C ₂The part of-20%NiCr flame coated film and epoxy resin surface film is equipped with grid lines, and this part is not section.Guide vane 110 places before the impeller eye, enters impeller so that form gratifying current by the angle of its blade-section 202.Because the impact that this blade-section 202 is subjected to the high-frequency particle is easy to take place the sandstone wearing and tearing, so it need to apply a kind of wear-resistant surfaces film.In the present embodiment, this blade-section 202 whole surface coating Cr ₃C ₂-20%NiCr flame coated film also scribbles the epoxy resin surface film on this coated film.

Figure 28 is the schematic cross sectional view of the vertical pump 115 of another embodiment of the present invention.One axle 117 that supports some blades 116 drives rotation by the main tumbler (not shown) that links to each other with these axle 117 1 ends, and therefore, water sucks from a suction inlet 251, discharges from an outlet 252.In Figure 28, icon 118 represents a bearing; 119 represent a shaft seal; Reach 120 and represent a shell.

Implement the part that parts of the present invention are blade 116 and shell 120.Blade 116 is described by way of example.Figure 29 is the schematic external view of blade 116.This blade 116 is made up of blade-section 261 and wheel shaft 262, and blade-section 252 is fixed on the end of wheel shaft.In Figure 29, scribble Cr ₃C ₂The part of-20%NiCr flame coated film and epoxy resin surface film is equipped with grid lines, and this part is not section.The vertical pump of present embodiment is used as the water-circulating pump in a flood discharge control pump or a power station.When this vertical pump in a great river, when using in the Yellow River, particle is impact blades 116 fiercely, thereby causes the sandstone wearing and tearing.In the present embodiment, for avoiding this sandstone wearing and tearing of blade 116, the whole surface of blade-section 261 all scribbles Cr ₃C ₂-20%NiCr flame coated film, and on this coated film, also scribble the epoxy resin surface film.This blade 116 is foundry goods normally, or is made by cast steel, and the use that often pulls the plug.If cast steel is coated with Cr ₃C ₂-20%NiCr flame coated film, iron material below and Cr ₃C ₂Galvano-cautery can take place between-20%NiCr flame the coated film.Epoxy resin surface film 109 not only is used to improve abrasion resistance, and is used to prevent electro erosion and improves corrosion resistance.

The common effect of above-described embodiment, effect and result of the test will be described below.

Cr ₃C ₂The hardness of-20%NiCr skin covering of the surface can be with Cr ₃C ₂The variation of content and changing.Work as Cr ₃C ₂When content increased, the hardness of skin covering of the surface improved, but its toughness descends and becomes fragile to cause the skin covering of the surface cracking and peel off, thereby reliability is reduced.To Cr ₃C ₂Cr in the-20%NiCr skin covering of the surface ₃C ₂Content is tested.Find that from test result weight percent is more suitable for desertification stone mill damage and cavitation resistance 50 to 90%.If sandstone density is higher, as in the Yellow River, the Changjiang river or descended the korneforos of heavy rain, just must improve Cr ₃C ₂Content to increase the hardness of skin covering of the surface.In this case, Cr ₃C ₂Content be preferably 70 to 90% weight percents.Considering from corrosion resistance, skin covering of the surface hardness and toughness, is proper with Ni, Cr or Co as the metal ingredient of skin covering of the surface.So for considering on corrosion resistance, skin covering of the surface hardness and the toughness that it will be appropriate therefrom selecting a kind of or incite somebody to action wherein several combinations.

Cr ₃C ₂-20%NiCr skin covering of the surface has Vickers hardness and the splendid corrosion resistance of an about Hv1000.The main matter of forming sandstone is feldspar and quartz, and quartz maximum hardness wherein is Hv1000.When the hardness of skin covering of the surface surpassed the hardness of impinging particle, abrasion resistance improved fast, and the skin covering of the surface that therefore has about Hv1000 hardness by coating can provide enough desertification stone mills to decrease or anti-cavitation erosion ability.

Because, the tiny cave of some so Cr are arranged in the flame-spraying film ₃C ₂The thickness of-20%NiCr skin covering of the surface is necessary for 0.1mm or thicker, to embody splendid anticorrosive and abrasion resistance.On the other hand, along with the increase of flame spraying film thickness, its internal stress also increases thereupon, so that has reduced adhesive quality.On the tack this point, Cr ₃C ₂-20%NiCr skin covering of the surface can only be thick or thinner for 1.0mm.Have again, from Cr ₃C ₂The antiwear property aspect of-20%NiCr skin covering of the surface considers that thickness 1.0mm just can guarantee the sufficiently long life-span, and for the consideration that reduces workload and energy savings, thickness is preferably 1.0mm or thinner.

In the present embodiment, with Cr ₃C ₂-20%NiCr skin covering of the surface is as the flame coated film, and still, the present invention is not limited to this kind composition.Higher so that need one more during the skin covering of the surface of high hardness when the sandstone density in the processed water, WC-NiCr skin covering of the surface or WC-Co skin covering of the surface are desirable the selections.These WC-NiCr skins covering of the surface and WC-Co skin covering of the surface on hardness and desertification stone abrasiveness than Cr ₃C ₂-20%NiCr skin covering of the surface is superior, and still, they cause toughness decline because hardness is higher, so be easy to cracking.This just means that WC-NiCr skin covering of the surface and WC-Co skin covering of the surface are not both having the gravel collision, and it is best that sandstone density is used in the not high situation again.

If skin covering of the surface is WC-NiCr skin covering of the surface and WC-Co skin covering of the surface, the hardness of skin covering of the surface can change to some extent with the difference of WC content, this and Cr ₃C ₂The situation of-20%NiCr skin covering of the surface is identical.When WC content increased, the hardness of skin covering of the surface improved, but its toughness descends and becomes fragile to cause the skin covering of the surface cracking and peel off, thereby reliability is reduced.When WC content is in 50 to the 90 weight percent scopes, can reaches enough desertification stone mills and decrease skin covering of the surface hardness, can keep certain toughness simultaneously.Have, in this scope, therefore skin covering of the surface tool one Hv1000 or higher hardness can obtain fabulous anticorrosive and abrasion resistance to prevent the sandstone wearing and tearing again.

If skin covering of the surface is WC-NiCr skin covering of the surface and WC-Co skin covering of the surface, in these skins covering of the surface, with Cr ₃C ₂-20%NiCr skin covering of the surface is similar, has the trickle hole of some.Therefore in order to present splendid anticorrosive and abrasion resistance, this skin covering of the surface must have a 0.1mm or thicker thickness.On the other hand, along with skin covering of the surface thickness increases, the stress in the skin covering of the surface also increases thereupon, so that has reduced tack.On the tack this point, WC-NiCr skin covering of the surface and WC-Co skin covering of the surface can only be thick or thinner for 0.5mm.Have, consider that from the antiwear property aspect of WC-NiCr skin covering of the surface and WC-Co skin covering of the surface thickness 0.5mm just can guarantee the sufficiently long life-span, for the consideration that reduces workload and energy savings, thickness is preferably 0.5mm or thinner.

In the aforementioned embodiment, Cr ₃C ₂Also scribble thickness on the-20%NiCr skin covering of the surface and be 1 to 2mm epoxy resin surface film.Other is not coated with Cr ₃C ₂The part of-20%NiCr skin covering of the surface, the flow velocity that flows through fluid is lower, and it is also lower to be subjected to the frequency of sandstone collisions.But if wearing and tearing do not detect to sandstone, sandstone wearing and tearing and cavitation erosion still can cause wearing and tearing, thereby have seriously reduced performance.Have again, as not carrying out the sufficient space of flame application job, just can not the gratifying flame coated surfaces film of coating.

In the higher zone of flow velocity, the epoxy resin surface film lacks enough desertification stone mills to be decreased and cavitation resistance.If ceramic particle such as alumina particulate are dispersed in the hardness that increases skin covering of the surface in the epoxy resin surface film, just can present enough abrasion resistances in zone relatively low at flow velocity, that the sandstone collision frequency is also lower.Have again, different with the flame coated film, even can be coated with the satisfied skin covering of the surface of last layer easily at the position that does not have enough spaces such as channel interior etc.Usually, always peeling off of flame coated film begins from the end of skin covering of the surface.By on the flame coated film, being coated with in addition epoxy tree table facial mask, thereby having become the lower floor of epoxy tree table facial mask, the end of flame coating suppressed from peeling off that the skin covering of the surface end begins, therefore improved reliability.In brief, by with Cr ₃C ₂-20%NiCr flame coated film combines with the epoxy resin surface film of the film formed double layer surface film of epoxy resin surface and individual layer, just can improve the abrasion resistance of whole parts.

In the present embodiment, described resin surface film is mixed the resin that is prepared into and is come illustrational by a kind of 50% weight percent alumina particulate and 10% weight percent hardening agent by will having one 10 to 40 micron particles diameters with bifunctional epoxy resin.The content that increases aluminium oxide can improve the hardness of resin surface film, but its toughness can reduce and become fragile, so that the generation skin covering of the surface breaks easily, and this has just reduced reliability.If the content of alumina particulate is in 20 to 70% weight percent scopes, desertification stone abrasiveness and toughness can get both so.On the other hand, preferably the diameter with the collision grains of sand is identical or bigger than it for the diameter of particulate.Allegedly the contained grains of sand have about 8 to 12 a microns mean particle dia in the river.If use in river, the size of infiltrating particulate is preferably 10 microns or bigger.

In the present embodiment, resin film is next illustrational by the epoxy resin surface film that contains alumina particulate, and still, the present invention is not limited to this composition.This resin film can be the skin covering of the surface of the liner of a kind of ebonite, polyethylene or polyester.The same with the epoxy resin surface film, these skins covering of the surface also can apply narrow space admirably, and such as channel interior, all right and inorganic particles mixes such as alumina particulate.Because the resin surface film can form a skin covering of the surface than flame coating thickness, therefore for the lower and suffered sandstone collision frequency of the flow velocity that flows through fluid also lower part, can demonstrate enough abrasion resistances.

On the other hand, the particulate that mixes usefulness also is not limited to aluminium oxide, all right other metallic dust, and as iron, copper or stainless steel, or ceramic particle, as titanium oxide, magnesium oxide, chromium oxide, silica, chromium carbide, Tungsten carbite, silicon carbide or silicon nitride.The diameter that the diameter of hybrid fine particles cans be compared to impingment particle most is big, as previously described.

In addition, when illustrating the resin surface film not with the epoxy resin surface film but with the skin covering of the surface of the liner of ebonite, polyethylene or polyester, coating process also should be limited to be smeared/oven drying method.

According to the present invention, can obtain a kind of pump or water turbine, this pump or water turbine resistance to wear and corrosion resistance aspect be so outstanding so that it can contain in fluid under the situation of sandstone uses, and can make this pump or water turbine with a rational cost-effective ground.

Claims

1. pump, it comprises:

A shell that is formed with a fluid passage;

One is arranged in the rotor in this passage, and this rotor comprises the axle sleeve, the cover cap and the blade that described axle sleeve is linked to each other with described cover cap around this axle sleeve that are positioned at its center portion; And

One is matched with described axle sleeve and to be used for rotating the axle of described rotor,

It is characterized in that: the mask that contacts with described fluid of described rotor and described shell has: one is formed with the zone of a first surface film of selecting from the skin covering of the surface group that comprises Ni alloy surface film, boron diffusion face film and chromium diffusing surface film; With one be formed with a zone that contains the second surface film of a kind of metal and a kind of carbide.

2. pump as claimed in claim 1 is characterized in that: the described zone that is formed with the second surface film is positioned at outlet (23a) and suction port part (23b), the outlet (22a) of described blade and the rotor outlet of suction port part (22b) and described shell of described cover cap and faces part (5a).

3. pump as claimed in claim 1 or 2 is characterized in that: described first surface film and second surface film have an overlap region, and in this overlap region, described first surface film is clipped between described rotor and described shell and the described second surface film.

4. pump as claimed in claim 1 or 2 is characterized in that: described second surface film contains a kind of at least a metal and a kind of chromium carbide or a kind of Tungsten carbite of selecting that comprise from the metal group of Ni, Cr and Co composition.

5. pump as claimed in claim 3 is characterized in that: described second surface film contains a kind of at least a metal and a kind of chromium carbide or a kind of Tungsten carbite of selecting that comprise from the metal group of Ni, Cr and Co composition.

6. method of making a kind of pump, this pump comprises:

A shell that is formed with a fluid passage;

One is matched with described axle sleeve and to be used for rotating the axle of described rotor, and this method comprises: described rotor and described shell gone up the coating one first surface film of selecting with contacted of described fluid from the skin covering of the surface group that comprises Ni alloy surface film, boron diffusion face film and chromium diffusing surface film; Afterwards, the second surface film that coating one contains at least a metal of selecting and a kind of chromium carbide or a kind of Tungsten carbite from the metal group that comprises Ni, Cr and Co on identical described; Then, described is heated under 400 to 600 ℃ of temperature.