CN1308129C

CN1308129C - Moulding method and appts.

Info

Publication number: CN1308129C
Application number: CNB028156668A
Authority: CN
Inventors: 尼古拉斯·W·J·彻里; 爱德华·I·科西奥
Original assignee: Pbt (nsw) Pty Ltd
Current assignee: P B T (新南威尔士)有限公司; Pbt (nsw) Pty Ltd
Priority date: 2001-06-20
Filing date: 2002-06-20
Publication date: 2007-04-04
Anticipated expiration: 2022-06-20
Also published as: WO2002102567A1; AUPR583701A0; CN1541156A; HK1070859A1

Abstract

A rotational mould and method of using the rotational mould is described for producing a pipe or similar product. The mould is provided with a distribution means in the form of a spiral or helical ridge, rim or raised section located spirally or helically on the inner surface of the mould to assist in directing the movement of material added to the mould, so as to provide a uniform distribution of the material in the mould in accordance with the desired end products required of the finished product. The distribution means can take a number of different forms as needed to transport or convey and distribute the material throughout the mould.

Description

Die-manufacturing method and equipment

The present invention relates generally to use a kind of mould to make the particularly method and apparatus of moulding article moulding of goods.Particularly, the present invention relates to use a kind of unitary mould to form moulding article, particularly substantial symmetry, especially to the goods of its central shaft basic symmetry.More specifically, to the present invention relates to be cylindrical rotation molding basically, as the equipment and the method for pipeline, flexible pipe, pipe, conduit etc.The present invention finds by a kind of special application of mould in the method and apparatus that improves the rotation molding with distribution apparatus of the distribution that can improve the raw material that enters mould is provided, so that manufactured goods have predetermined performance or characteristic.This distribution apparatus can be can move or be transportable according to the mobile of mould according to mould.So that in mould, press predetermined way distribution raw material.In one type, this distribution apparatus is that a kind of mould inside that is arranged on is for example in the spirality of the inwall of this mould or spiral yarn shaped, so that the supplied materials in the distributed die equably more or less.

Though the present invention will specifically describe with reference to a kind of pattern making equipment of the present invention and process, it should be noted that scope of the present invention is not limited to described embodiment, but scope of the present invention is more extensive so that comprise the purposes of other forming method and equipment and the method and apparatus in other uses than specifically described.

In the past, the rotation molding had been used to make many kinds of objects, particularly cylinder or to the object of its central shaft symmetry.Past, raw material is introduced mould, mould rotation and raw material solidify to form object or goods.Yet, in effective method and the equipment, appear at the relevant problem of feed distribution in the mould in the past.In many cases, raw material does not evenly distribute.Under the situation of object of being made by two or more different materials or goods, be difficult to evenly distribute according to the final requirement of this object or goods two kinds or whole raw materials are so that it has desired performance or characteristic.Therefore, have requirement provide a kind of make the raw material of introducing mould have better distribution in case make the desired performance of finished product or characteristic more even.

Therefore, an object of the present invention is to provide a kind of method and apparatus that is used to rotate molding object or goods, this method and apparatus can improve the distribution of the raw material of introducing mould.

And in the past, the manufacturing of pipeline, pipe, flexible pipe etc. generally includes equipment such as extrusion equipment and the extruder that uses processing continuously.Have shortcoming by the small-bore or small diameter pipeline of extrusion process manufacturing etc., thereby to handle be the continuous continuous length pipeline that produces in processing.Must cut to desired size after extruding continuous length then, this requires the procedure of processing of extra time-consuming, effort and expense.In addition, starting extrusion machinery equipment until adjusting in the process of proper working parameters with trial and error procedure usually, extruded product must abandon during this, thereby has waste of material.Sometimes need further handle the flexible pipe of the cutting of extruding continuously or the end of pipeline, for example, finishing or arrangement flexible pipe or pipeline terminal or add suitable fixture or male part at the end of flexible pipe or pipeline.

When making larger-diameter pipeline, for example, has the pipeline that surpasses 200 mm dias, because pipeline can only be with continuous length production, this significantly increases cost of material and quantity in stock, and when particularly only requiring the pipeline of a small amount of designated length, it is expensive using extrusion equipment.Thereby, in the manufacturing of minor diameter and big-inch pipe, be necessary to reduce the expensive instrument and the expense of extrusion machinery equipment of supplying, and be necessary to avoid raw-material waste.

Therefore, a target of the present invention provides a kind of being used for and uses the object of discrete length of rotation molding different-diameter of minimum raw material or the method and apparatus of goods at comparatively cheap mould.

Another problem than the hobbing of the pipe of minor diameter or larger-diameter pipe is to make the pipe fixture with different shapes, as the finished product of extruding of the continuous length of coupling flange etc.It is molded when the rotation molding of pipe etc. allows fixture such as flange, horn mouth end and moulding tubes, thereby save pipe is extruded the required continuous length in back at continuous length following process, so that connect and seal the pipe of discrete length, for example by the fixture of two ends that are specifically designed to the pipe that connects the extruding of cutting is provided.Thereby, when methods such as using the rotation molding forms pipe, be necessary to provide fixture and different shapes.

Therefore, an object of the present invention is to provide a kind of method and apparatus that is used to rotate molding object or goods, this object or goods, have special fixture or feature molded and advance on the end or wall of object or goods during in molding at goods or object.

A kind of equipment that is used for moulded products is provided according to a first aspect of the invention, comprises a kind of shaped device that is used to form the general shape of these goods; A kind ofly introduce raw material so that in this shaped device, form the guiding device of goods to this shaped device; With the distribution apparatus of a kind of raw material of distribute introducing this shaped device in whole shaped device with the general shape that helps to form goods, wherein moving in shaped device of shaped device and/or distribution apparatus distributed raw material so that goods can be with predetermined performance or characteristic moulding in previously selected mode.

According to a further aspect in the invention, provide a kind of method of forming of goods, comprise step: a kind of raw material that is used to form these goods is provided; Introduce this raw material, come mobile shaped device and/or distribution apparatus to be introduced into the raw material of this shaped device and to use this shaped device to form goods to this shaped device by using a kind of guiding device of being furnished with a kind of distribution apparatus so that distribute according to desired pre-determined characteristics of goods or characteristic.

Usually, this object, part, goods etc. are a kind of object of symmetry or the object of substantial symmetry.More typically be, goods be to its central shaft symmetry or substantial symmetry.More typical is that this object is a kind of cylinder of hollow.More typically be that these goods are that a kind of pipeline, flexible pipe, conduit, pipe or other are columniform hollow object or part basically.

Usually, the raw material that forms this object is raw material or unworn raw material or both mixture of circulation.More typical is that raw material is a kind of thermoplastic, preferably a kind of thermoplastic of circulation.More typically be, depend on the final performance of desired object, raw material comprises a kind of, two kinds, three kinds, four kinds or more kinds of different raw material, these raw materials are introduced equipment of the present invention at different time.

Usually, this raw material is a polyethylene.More typical is that raw material is low density polyethylene (LDPE) (LDPE), linear low density polyethylene (LLDPE) (LLDPE), high density polyethylene (HDPE) (HDPE), ethylene-vinyl acetate (EVA), polypropylene, acronitrile-butadiene-styrene (ABS) or its analog.

Usually, raw material is high density polyethylene (HDPE) (HDPE) or medium density polyethylene (MDPE).Be typically, raw material has about 950 to 960 kilograms per cubic meter of density and a kind of melt flow rate (MFR) (at 190 ℃ following 2.16 kilograms) is 0.1 to 4 gram/10 minutes, and preferably 0.5 to 1.0 gram is/10 minutes.

Usually, raw material can have multiple different shape, comprises flowing freely shape, as powder, pill, thin slice, particulate, particle, pearl, button-type, needle-like, fragment, smear metal etc.

Usually, the raw material that is used to form object is to use with a kind of free-pouring shape.A kind of preferred shape of raw material is that a kind of thickness about 0.5 to 1.5 millimeter and length and width about 5 are to about 20 millimeters flat thin slice.A kind of particularly preferred raw material is the HDPE bottle that derives from chopping, for example used feeding bottle etc.

Usually, thermoplastic can make in many ways to make pipeline with quite extensive performance, flexible pipe, conduit, pipe etc.Plastics can be used alone, and for example, make the whole wall thickness that obtains goods form the more or less individual layer of homogeneous performance; And use successively so that a kind of structural effect layer is provided, the different layers that wherein forms the raw material of pipe or hose wall has different performances, perhaps use as a kind of mixture, meticulously selecting under the fusing point and particle diameter of this component, with the dispersion of control that a kind of different component raw material or hierarchy are provided.

Usually, method and apparatus of the present invention has big endurance to pollutant.More typically be, if there is any pollutant to exist, the moulding in this way of these goods, this pollutant is positioned at away from the critical appearance section of this pipe or flexible pipe and near those nonessential inner surfaces.More typical is that pollutant comprises moisture, other resins or plastic raw materials, dirt, finish, grease, dust, impurity particle etc.

Usually, shaped device is a kind of mould.More typically be, mould is a kind of unitary mould, usually, is a kind of cylindrical die with integral wall structure.More typical is that this cylindrical die has the opening of one or both ends.More typical is that any surface characteristics of pipe can form in mold wall; The existence of inspection opening, cover plate, interface, delivery outlet, flange, horn mouth or other fixture etc. for example, is arranged.

In addition, this method comprises the step of heating mould, comprises the outer surface of heating mould or the inner surface of mould, or heats inside and outside two surfaces successively or simultaneously.

Generally, method comprises the step of additional cooling die and/or goods.More typically be, externally or inner or inside and outside cool off, and can cool off successively or simultaneously.More typical is that cooling comprises that by using air, water, air/water mixture injection, smog etc. carry out.More typical is that cooling is can be applied to inside, outside or inside and outside cooling agent by use finish.

Be typically, equipment of the present invention uses the layout of single or multiple cylindrical shell, and cylindrical shell can feed and rotate in the heating and cooling process.A kind of particularly preferred scheme is that every manufacturer uses a cover or two sleeve bodies.

Usually, this distribution apparatus is arranged on the inwall of mould.More typical is that this distribution apparatus rotates according to mould.More typical is that this distribution apparatus is fixed on the inwall of mould.More typical is that this distribution apparatus extends with spiral yarn shaped or spirality along the inwall of mould.A kind of particularly preferred distribution apparatus is a kind of spiral weldable steel edge that is welded to mould inner wall, steel rib, steel band etc.

Usually, distribution apparatus is that a kind of solder joints is scroll or becomes the metal tape of spiral yarn shaped coiling or the neighboring edge of bonding jumper.More typical is that this welding is located at mould outside and the inside.More typically be about at the most 10 millimeters of this weld width, preferably 1 to 5 millimeter, 2 to 3 millimeters width more preferably.Be typically, this helical angle can be arbitrarily angled, preferably between about 20 to 90 degree, more preferably between 45 to 85 degree, most preferably between 60 to 80 degree.

Usually, about at the most 10 millimeters of this throat thickness, preferably thickness is about at the most 5 millimeters, more preferably 1 to 2 millimeter.

Usually, use by the steel band of spiral shell shape coiling to weld together with edge-to-edge's relation and the cylindrical shell made is particularly advantageous, this be because it can raise slightly inner helical surface be used to distribute thin slice away from or introduce point towards raw material.Introducing the direction of motion of the raw material of mould controls with respect to the direction of the rotation of the hand of spiral of distribution apparatus by cylindrical shell.

Be typically, in the design of an end of cylindrical shell opening arranged, it makes the cylindrical shell rotation and introduce raw material simultaneously in cavity.More typical is that this guiding device is the openend of cylindrical shell or mould one or both ends.More typical is that the mould one or both ends are provided with a kind of conveyor hopper etc. to be used to admit a selected amount of raw material that enters this mould.

Be typically, the heating cylindrical shell is so that make thermoplastic be converted into a kind of fluid material, and it can flow between plastic tab and solidify.Heating can be finished by multiple technologies, for example directly uses gas arc lamp on the length direction of drum surface.

Be typically, this mould, preferably, the cylindrical shell of mould can scribble a kind of releasing agent in inside, for example a kind of hydrocarbon ils, a vegetable oil or silicone oil etc.

Be typically, method of the present invention can by control pack into the different material quantities, mould of mould and wherein the temperature that reaches of rotating speed program, heat time heating time and each concrete stage of raw material control the even distribution and the density of the wall section of pipe or analog.More typical is that the elimination of intergranular sand holes can be controlled by the temperature of accurate rotary speed program and tube wall raw material.This can measure inner temperature and corresponding adjustment operating condition by the equipment of design and reach.

Be typically, the density of wall section with eliminate the wall relevant with rotating molding in sand holes can control by the design of equipment, when but raw material is melted and be in shaped state, gas that can be by raw material and steam are exerted pressure to mould inner wall and to the supercharging of wall section, so that obtain a kind of goods that have less sand holes equivalent risk more closely.

Be typically, the cooling of pipe has bigger thermal capacity than independent air by introduction cooling agent quickens to surpass conventional cooldown rate as the air that mixes with water smoke or other raw material.Outside and inner at mould, accurately the inside sand holes that form because of contraction with the plastics of avoiding melting are cooled off in control when it solidifies.In mould, introduce cooling pulse can do not form sand holes situation under quicken cooling.

The cycle rate that is typically, processes depends on the careful judgement of cool time strongly so that the thermoplastic discharge of suitably solidifying.The audio detection that the measurement of inner temperature is shunk with caliber can be determined minimum cool time and can make the mould emptying and be used for the next round circulation, thereby boost productivity and reduce cost.

Be typically, heat in the big envelope of insulation, this makes relevant thermal loss reduce to minimum in the heating part process of circulation.

The rotation of pipe is by changing the variable-speed motor control of rotating speed in manufacture process.In the plastic raw materials process of packing into to mould, speed is set to speed slowly, and when the control plastic tab distributes, the state that gathers way and make raw material be " rainfall " to reach.Should describe plastic tab " rainfall " stage and rotate the summit of arrival pipe also under gravity from return the process that drops to lower surface away from wall with pipe.This can make thin slice evenly apply as a kind of coating on the metal surface.In case obtain evenly to distribute, gather way with prevention plastic grain " rainfall ", and higher centripetal force makes raw material remain on the appropriate location.In this stage, begin to heat cylindrical shell.This can make the softening and fusing of plastics.Use higher centripetal force curing thin slice and accelerate fusion process by getting rid of bubble and possible defective.

Be typically, after all plastics are melted in the cylindrical shell rotation, by this pipe of inside and outside cooling.In rotary course, utilize special openings by cylindrical shell one end to be blown into to do or humid air carries out inside and cools off.Carry out external refrigeration with dry air or water injection.Coordinate cooling and control the curing of molten plastic well to guarantee external refrigeration.Too fast inside cooling causes producing sand holes defective (because contraction of molten plastic) in the central authorities of pipe cross section.

Be typically, in case pipe be cooled, but the demoulding at any time of this pipe.Design holistic flange or horn mouth section at pipe one end the follow-up molding of pipe is connected, and can make this pipe automatic demoulding from mould.This is caused because of the volume contraction of molten plastic, and it has 0.1 to 9% contraction at linear direction, preferably 0.5 to 3.0% contraction and more preferably 0.5 to 1.0% contraction.Settle flange to cause the free end of this pipe to shrink at pipe one end to flange.The contraction of diameter causes this pipe to be freed from die surface.In cooling procedure, these two kinds of effects cause pipe to be freed and removable at any time from mould automatically.

Be typically, mould inner wall be have tapering to help the demoulding of pipe from the mould.

Be typically, the improvement of this barrel designs can make special flange and horn mouth end portion be molded in situ on the pipe, saves the pipe extruded for the ease of connecting and sealing tube length and necessary following process.Be typically, heat cylindrical shell so that thermoplastic resin is converted into energy flowing liquid state, and between plastic tab, solidify.Heating can be undertaken by multiple technologies, for example, and by directly using gas arc lamp at drum surface.After packing into, heats raw material surface heating and the removing of control sand holes and the thickness of pipe that cylindrical shell and rotary barrel produce homogeneous.Temperature is raised to more than the fusing point of plastic resin.Under the HDPE situation, the temperature in the pipe may be raised to also may be up to 250 ℃ more than 140 ℃.

With reference now to accompanying drawing by reference non-restrictive example as a reference to describe preferred version of the present invention.Wherein:

Fig. 1 is a kind of mould that a kind of method and apparatus according to the invention is used to form pipe, at the approaching side view that is used for the disk end place of closed mould one end;

Fig. 2 is the cutaway view shown in Figure 1 that shows the mould part that slice raw material is housed;

Fig. 3 is that expression enters thin slice that tube wall forms to the mould inner wall cutaway view of mould when rotated;

Fig. 4 shows the perspective view of pipe mould shown in Figure 1 when removing from mould;

Fig. 5 is a kind of part sectioned view that uses the pipe of method and apparatus formation of the present invention;

Fig. 6 is illustrated in mould and tube interior and outside heating or the mould of cooling device and the cutaway view of pipe of using;

Fig. 7 is the cutaway view that utilizes the pipe of a kind of stratiform that method and apparatus of the present invention forms;

Fig. 8 is a kind of close-up view that forms the mould of flange at pipe one end;

Fig. 9 is a kind of perspective view with pipe of flange; With

Figure 10 is the diagrammatic cross-sectional view that is welded on a kind of distribution apparatus of mold periphery with spirality or spiral yarn shaped form.

In Fig. 1 to 7, a kind of specific embodiments of expression shaped device of the present invention, mold form with substantial cylindrical, generally with 2 representatives, have and be positioned at or near first opening 4 of mould 2 one ends be positioned at or, form a whole cylindrical die that openend is arranged like this, wherein can form pipe near second opening 6 of mould 2 other ends, usually represent with 10, or similar object.Opening 6 can randomly be used the sealing of removable cover 8, disk and plate or analog.Mould 2 can be by opening 6 fillings.Opening 6 can be formed for the guiding device that will be in mould 2 molded raw material is introduced mould 2.Can there be the mode of other introduction to comprise the automatic feeder of mould.

Mould 2 can be made by any good Heat Conduction Material, for example metal, as the alloy of iron, steel or metal, or other appropriate synthetic materials comprises the combination of different materials thing.This mould preferably by a kind of heat-resisting and good Heat Conduction Material manufacturing, is preferably made by steel.Cylindrical shell can be made into positive tapering or basic zero draft.By making plastic raw materials shrink about process of 0.5 to 1%, make pipe be easier to from this cylindrical shell, remove at linear direction.

With particular reference to Figure 10, represent a kind of distribution apparatus, this distribution apparatus 16 is with spiral 12 or spiral yarn shaped ridge, edge or similar form and be arranged on mould 2 inside.In one type, mould 2 is by a kind of suitable bonding jumper or be with the coiling of 14 spiralitys ground to form, and welds to form mould 2 so that form with edge-to-edge's relation or with edge-to-edge's overlapping relation spiral.Bonding wire or analog 16 are ticked spirality or spiral yarn shaped passage at the inner surface of mould 2.Optional is, or additional be to have bonding wire 18 in the outside of mould 2.To manufacture mould be advantageous particularly by being the scroll weldable steel in use and since it can be along inside spin surface that helical margin raises slightly with the raw material that is used to distribute away from, or the introducing point of trend plastic raw materials.The direction of motion of plastic raw materials is controlled by the direction that mould 2 rotates with respect to the formed hand of spiral of spiral on mould 2 inwalls.In another embodiment, inner surface, with optional be that outer surface is to be formed by the strip metal band that has with the welding of the nested overlapping relation of part, the various piece that causes being the inner surface of scroll coiling is that tapering or angle are arranged, to help to guide the motion of plastic raw materials in the entire die.

Fig. 1 and 2 represents to be filled into granular plastic raw materials 16 mould 2 of desired height 14.In one type, plastic raw materials is normally by the plastics of crush cycle use or bottle, lid and other container of similar raw material, the formed plastics that chop up.Before introducing mould 2, a spot of other pollutant that plastic raw materials 16 needn't clean the gummed paper label of removing liquid residue or having removed or remove is because can allow to contain an amount of pollutant in the raw material of molding.

This raw material can be of the same type or mix the plastics of polytype, grade or composition or other raw material.Particularly preferred raw material is that thickness about 0.5 to 1.5 millimeter and length and width about 5 are to about 20 millimeters slice raw material.Should be noted that wide variety allows in these sizes.

During beginning that the central shaft 18 that Fig. 2 represents to extend along the longitudinal with direction shown in the arrow A when mould 2 slowly rotates, wherein the layer of plastic raw materials 16 is to be collected in mould shown in Figure 22 bottoms.Along with mould 2 continues slowly to rotate, force mould inner wall one side so that the inwall facing to this mould falls after rise as " rainfall " shape in mould to such an extent as to plastic raw materials 16 also rotates, thereby cover the entire die wall.As long as this mould rotates with lower speed, " rainfall " of this raw material just will continue so that center on the mould inner wall raw material that evenly distributes more or less.Should " rainfall " process can keep on request.When mould 2 rotating speeds increased, the inwall that the centripetal force on material web will increase to cause raw material to face toward mould accumulated with homogeneous thickness.The rotating speed of mould 2 will make raw material face toward mould inner wall and remain on the appropriate location.

Be typically, the rotation of pipe is by allowing can change the variable-speed motor control of rotating speed in manufacture process.In mould charging feedstock process, speed is set to speed slowly, and the control plastic tab is when distributing, and gathering way makes raw material be " rainfall " state to reach.Should describe plastic tab and pipe " rainfall " stage and rotate the summit of arrival pipe together also under gravity from return the process that drops to lower surface away from wall.Thin slice is applied equably as the coating on a kind of metal surface.In case obtain evenly to distribute, gathering way keeps in position raw material with " rainfall " and the higher centripetal force that stops plastic grain.In this stage, begin to heat this cylindrical shell.This allows the softening and fusing of plastics.Use higher centripetal force to solidify thin slice and accelerate fusion process with the possibility latent defect by getting rid of bubble.

In some specific embodiments of present device, a kind of burner or analog are arranged on the outside of outer wall of mould 2 so that to the heating of the outer wall of mould 2, and wherein former of heating expected softening and melt raw material, and a kind of burner as shown in Figure 6.This thermal source is not limited to the burner that is arranged in the outside and can is other arrangement that is applicable to the burner of heating mould 2, for example is included in mould 2 inner heating.Another kind of heating is in mould 2 walls electrical heating to be set.

In specific embodiments shown in Figure 6, arrange gas conduit 20 along the length bearing of trend of mould 2.Burner 22 is that the length at whole conduit 20 is provided with spaced apart.Burner 22 can ignited flammable gas with heating mould 2.Optional is, can further be provided with to have with the conduit 24 of the burner 26 of spaced apart so that heat and/or can make tenderizer that the pipe that forms in this mould is carried out inner polishing mould 2 is auxiliary mould 2 in.

The operation of present device is described now.

The suitable plastic raw materials that recycles that chops up 16 adds in the mould 2 by openend 6.In one embodiment, rotate before the beginning, the plastic material 16 of capacity joins in the mould 2; And in another embodiment, before any raw material added, mould 2 just began to rotate.Along with the rotation of mould 2, add raw materials and be spiral 12 or spiral yarn shaped distribution apparatus along mould 2 length direction distribution raw materials by being arranged on mould 2 inwalls by mould 2 openends 6.When the raw material of capacity joins in the mould 2, cover 8 and be in suitable position so that this mould 2 can make raw material " rainfall " form a kind of plastic raw materials layer uniformly basically to the inwall than continuing rotation under the low velocity thereby can make.

When plastic raw materials 16 forms a kind of layer or when covering uniformly basically at the inwall of mould, thereby this mould utilizes the effect of entad motion and the power raw material that further distributes with the fast speed rotation.Then, the outside of heating mould, inside or inside and outside combine.

Quicken to rotate and the effect of heating under, thereby plastic raw materials fusing and flow that to form a kind of be the homogeneous mixture of the uniform thickness of homogeneous basically.After pipe forms, when rotating, stop heating and cooling die 2 with the shape of guaranteeing to keep pipe.Plastic raw materials hardens and shrink slightly in cooling procedure.Be typically, about 0.5 to 3% in the linear direction amount of contraction, be typically, shrink 0.5 to 1% at linear direction.

Need or requirement be arranged if having, but cooling die.This cooling can be used for outside, inside or inside and outside.Cooling can be quickened air or air such as forms such as smog or injection by mixing with water by air or fan, or cooling can be finished by using cooling agent.In one type, when rotating, the outer surface of mould 2 in water-bath or in the coolant bath in case the wall that when mould rotates, passes through mould 2 from the external refrigeration pipe.

Thereby preferably evenly apply cooling or prevent pipe layering or separation or form sand holes the cooling step process so that make the thickness of whole pipe have even cooling from the both sides cooling.

If suitable, can remove at the lid of mould end and owing to the shrinkage factor of this pipe can be removed the pipe of this moulding from mould 2.Do not require peel of mould each several part or other the technology of removing, this has simplified whole production method and has also helped to reduce significantly simultaneously labour costs.

Load different plastic raw materials respectively and will allow to form concentric layer.A kind of raw material that recycles of can at first packing into so then is unworn raw material.With a kind of bilayer of form, pipe or analog, the circulation layer 26 that having as shown in Figure 7 is positioned at this tube exterior and be positioned at the inner layer of feed stock material 28 of not using.Such structure can make the pipe of moulding be used for being not limited to irrigation purposes with the purpose (human grade purposes) of relating to persons, because flow only control raw material by the liquid of this pipe.If there is not internal layer new or that do not use raw material, the purpose (non humanpurposes) that this pipe can only be used for haveing nothing to do with the people is as irrigating.

Method and apparatus of the present invention allows the technology of the various stratification of use to have the pipe of different layers with formation.The cambial method of a kind of different material is that the raw material with the tube exterior moulding is cut into the stippled plate littler than the raw material that will form internal layer.This mould is packed into have the thin slice of two kinds of sizes, and the rotating speed that increases mould makes its stroke pass raw material up to, granular thin slice and forms one at the inner surface of this mould cylindrical big thin slice continues to roll and forms the internal layer of this pipe so that form the skin of this pipe.Along with rotating speed increases, bigger thin slice forms concentric layer in more particle thin slices.The technology of this stratification can air turbulence promotes in the mould by increasing.This turbulence can produce by fixing or mutually despun carrier in the mould or the air that blows to mould inside.Turbulent flow helps sheet removing rather than bulk material.

The method of another kind of stratification is temperature to be set so that at first melt a kind of low melting point plastic raw material of particular form.Can form melting zone at the inner surface of mould.When temperature increased, second dystectic plastic surface layer formed the inner surface of pipe.Such two kinds of different raw materials can form separating layer.

The method of another stratification is to pack into first plastic raw materials of filling and begin processing of mould.When mould still rotates, add the second different raw material of filling then.The performance that depends on desired tube construction and each raw material, the second filling raw material can be to fill raw material first to melt front or rear the adding.If desired, can repeatedly feed in addition.In addition, might make pipe have different raw materials or combination raw materials three layers, four layers or more multi-layered.

At Fig. 8, illustrate to be shown in the modification of Fig. 1 to the mould 2 of Fig. 3.In the present invention, cylindrical die 2 has one and extends radially outwardly into terminal 34 flange 32.Have an annular flange 38 identical or suitable that extends radially outwardly into the end cap periphery on one end cap 36 with flange 32 diameters.Flange 38 and flange 32 couplings form the prolongation of the end of moulds 2.A kind of groove 40 of circle runs through flange 38 and enters blind hole in the end cap 36.The diameter of this circular trough 40 is greater than the external diameter of mould 42.

Pipe 42 is to form with the same manner shown in Fig. 1 to 3 in the mould with flange extremity and end cap.The flange 44 that the increase diameter of groove 40 can make pipe 42 as shown in Figure 9 on pipe 42 with the remainder of pipe 42 global formation simultaneously.Flange 44 can be formed by the solid plastic raw material, and when with pipe 42 global formations, can be very firm.The similar pipe 42 that all have flange extremity, can dock and clamping so that pipe splicing or be connected in the flange fixture of another integral device, for example, the outlet of the pump in irrigation system.

If the two ends at pipe 42 have all required flange, mould 2 can be made up of two or more parts connections in patternmaking process.When molding was finished, this mold component was separable so that allow to remove the pipe 42 of moulding.If the inside of mould 2 34 places endways is substeps, flange 32,34 can omit.Optional is, the end of pipe 42 can enlarge the circular section and enlarge the horn mouth cross section as one and form.

Method and apparatus of the present invention can be under lower price by considerably less pre-treatment of raw material or the preprocessing of pre-preparation conditioned disjunction or make a kind of useful goods.This method allows very big variation qualitatively and can use low-grade plastic raw materials raw-material.

If requirement is arranged, can use unworn plastic raw materials, perhaps combine with the plastic raw materials that recycles of part or as the raw material of separation layer.Also can in the raw material of filling, add chemical addition agent.

Advantage of the present invention comprises as follows:

Method of the present invention and technology enlarge the design that also improves the rotation molding, and the rotation molding generally is used for the discontinuous molding of discrete object such as totally enclosed hollow object such as storage tank and waits until conduit and the pipe that utilizes continuous processing equipment such as extruder to make.Advantage is to have the amount that reduces minimum flow process length and reduce discarded goods when starting, avoid expensive instrument and extrusion machinery equipment, therefore, significantly reduce the manufacturing conduit and particularly have the cost of diameter greater than 200 millimeters big conduits, the pipe of precise length quantity be can make by technology of the present invention, and conservation and pipe storage capability considerably allowed.Pipe can manufacture the length of appointment and needn't be for further processing for transportation, for example will not cut to desired length by pipe.

Available various raw material is made pipe etc., comprises low-grade raw material, the mixture of contaminated raw material and different material.

This processing technology allows the inspection opening, connector of in pipe special feature of moulded-in-place such as pipe, special flange and bell-mouthed end section, and this has saved in extrusion and has made in the pipe for the ease of connecting and the tube length of sealing and necessary following process.Extrusion is made in the continuous length pipe, has no chance to form the pipe with overall fixed part.

Described scheme is by explaining developed and can making many improvement not deviating under the prerequisite that the spirit and scope of the present invention comprise each new feature disclosed herein and new assemblage characteristic.

It will be recognized by those of ordinary skills, the present invention described here can also change and improve except those are specifically described.Certainly the present invention includes all these classes and fall into the interior changes and improvements of its spirit and scope.

Claims

1. equipment that is used for moulded products comprises:

Be used to form the shaped device of the general shape of goods;

Be used in the shaped device that is used to form goods, introducing the inlet of raw material; With

Be used in whole shaped device distribution shaped device raw material with the general shape that helps to form goods, along and the distribution apparatus that extends round the inwall of shaped device,

Wherein shaped device or distribution apparatus or both rotations distribute the raw material in shaped device to give at least a predetermined performance of the goods that form or characteristic in this equipment.

2. according to the equipment of claim 1, it is characterized in that: shaped device has inwall, and distribution apparatus extends with spiral yarn shaped or spirality along the inwall of shaped device.

3. according to the equipment of claim 2, it is characterized in that: distribution apparatus be welded to the shaped device inwall, twist or the steel edge of spiral yarn shaped welding, steel rib, steel wire or steel band.

4. according to the equipment of claim 2, it is characterized in that: distribution apparatus is fixed on the inwall of shaped device or forms the part of shaped device inwall.

5. according to the equipment of claim 1, it is characterized in that: shaped device is a hollow circular cylinder, and distribution apparatus is to be used for connecting the welding that forms the neighboring edge place of the bonding jumper of hollow circular cylinder device or band with spirality or scroll coiling.

6. according to the equipment of claim 5, it is characterized in that: this welding is positioned at the outside of shaped device, perhaps in the inside of this shaped device, or is positioned at the inside and outside of shaped device simultaneously.

7. according to the equipment of claim 5, it is characterized in that: this weld width reaches 10 millimeters at the most.

8. according to the equipment of claim 5, it is characterized in that: this weld width is between 2 millimeters to 3 millimeters.

9. according to the equipment of claim 5, it is characterized in that: the spiral angle of this welding is between 20 to 90 degree.

10. according to the equipment of claim 9, it is characterized in that: the spiral angle of this welding is between 60 and 80 degree.

11. the equipment according to claim 1 is characterized in that: shaped device is a mould.

12. the equipment according to claim 11 is characterized in that: shaped device is open-ended a slice cylindrical mold.

13. equipment according to claim 1, it is characterized in that: shaped device is a cylindrical shell, this cylindrical shell is to be welded together with edge-to-edge's relation by the steel band of spiral shell shape coiling to make, so that when cylindrical shell rotates, the internal helicoid face that slightly raise of this raw material by cylindrical shell contact in case according to the direction of rotation distribution material web of cylindrical shell away from, trend or in the porch.

14. the equipment according to claim 13 is characterized in that: one or two openend that this inlet is a cylindrical shell.

15. equipment according to claim 1, it is characterized in that: shaped device comprises mould, this mould is to be formed by the strip or the strip metal that have with the welding of the nested overlapping relation of part, so as each twist or become spiral yarn shaped coiling inner surface spiral with respect near part be have tapering, inclination or angled to help guiding raw material in entire die, to move.

16. the equipment according to claim 1 is characterized in that: inlet is to form with the strip of edge-to-edge's overlapping relation welding or strip metal.

17. equipment according to claim 1, it is characterized in that: the one or both ends of shaped device are provided with conveyor hopper being used to admit a selected amount of raw material that enters this shaped device, and automatic conveying device is used for from hopper raw material being transported to the shaped device import.

18., also comprise the heater that is used for the hot briquetting device according to the equipment of claim 1.

19. according to the equipment of claim 18, wherein heater be can with at the hot-air of shaped device inside center axially along the heater of the center guiding of the hollow of shaped device.

20., also comprise the cooling device of cooling forming device according to the equipment of claim 1.

21. the equipment according to claim 20 is characterized in that: the inner surface of shaped device scribbles releasing agent.

22., it is characterized in that releasing agent is hydrocarbon ils, vegetable oil, silicone oil or its combination according to the equipment of claim 21.

23. the equipment according to claim 1 is characterized in that: goods have central shaft, and these goods are along its central shaft symmetry or basic symmetry.

24. the equipment according to claim 23 is characterized in that: goods are to be the object of columniform hollow substantially.

25. the equipment according to claim 24 is characterized in that: described goods are selected from pipeline, flexible pipe, pipe or conduit.

26. the equipment according to claim 1 is characterized in that: the raw material that is used to form this object is recycle feed, original raw material or its mixture.

27. the equipment according to claim 26 is characterized in that: this raw material is a thermoplastic.

28. equipment according to claim 27, it is characterized in that: this raw material is a polyethylene, low density polyethylene, linear low density polyethylene (LLDPE) LLDPE, medium density polyethylene MDPE, high density polyethylene, ethylene-vinyl acetate EVA, polypropylene PP, acrylonitrile-butadiene-styrene (ABS) ABS or its combination.

29. the equipment according to claim 27 is characterized in that: this raw material is the mixture of high density polyethylene (HDPE) and medium density polyethylene.

30. the equipment according to claim 27 is characterized in that: this raw material derives from the HDPE bottle of chopping.

31. the equipment according to claim 30 is characterized in that: this bottle is the feeding bottle of using.

32. the equipment according to claim 1 is characterized in that: the density that is used to form the material of goods is 950 to 960 kilograms per cubic meter, and is 0.1 to 4 gram/10 minutes in the melt flow rate (MFR) that is had of 190 ℃ of following 2.16 kilograms of mensuration.

33. the equipment according to claim 1 is characterized in that: this raw material is free-flowing form.

34. the equipment according to claim 1 is characterized in that: this raw material is in powder, pill, thin slice, particle, pearl, button-type, needle-like, fragment, smear metal or its combining form.

35. the equipment according to claim 34 is characterized in that: the shape of this raw material is 0.5 to 1.5 millimeter of thickness and length and the width flat thin slice in 5 to 20 millimeters scope respectively.

36. the equipment according to claim 1 is characterized in that: the wall of these goods is stratification, has two-layer or the mutual stacked different material layer of multilayer.

37. the equipment according to claim 1 is characterized in that: shaped device has wall or wall surface, and this wall or wall surface are provided with at least a in following: connecting piece or other assembly parts comprise their combination.

38. the equipment according to claim 37 is characterized in that: described wall or wall surface setting are selected from: inspection opening, cover plate, interface, delivery outlet, flange, horn mouth.

39. the method for moulded products comprises the following steps: in shaped device

Be provided for forming the raw material of goods;

Raw material is incorporated in the shaped device by the inlet that is arranged on the shaped device, this shaped device be provided with along and be used for distribution apparatus round what the inwall of shaped device extended at whole shaped device distribution raw material;

Rotational forming device or distribution apparatus or both are incorporated into the raw material in the shaped device to distribute in shaped device, to give goods at least a predetermined performance; And

In shaped device, form goods.

40. the method according to claim 39 also comprises the following steps:

By the outer surface of hot briquetting device or the inner surface of shaped device, or the inner surface of shaped device and outer surface, perhaps carry out simultaneously or successively carry out and shaped device is heated.

41. method according to claim 40, it is characterized in that: in heating steps, execute being heated on the shaped device so that the raw material in the shaped device is transformed into fluent material, thereby fluent material can flow and consolidate, and forms material layer thus between material granule.

42. the method according to claim 39 also comprises the following steps:

Cooling forming device and/or goods, or by inner or outside or mode simultaneously, described cooling is order or is applied to simultaneously on the shaped device with refrigerated product.

43., it is characterized in that cooling off by using air, water, air and aqueous mixtures to reach according to the method for claim 42.

44., it is characterized in that air, water, air and aqueous mixtures are the forms that is spraying, mist or its combination according to the method for claim 43.

45. according to the method for claim 42, it is characterized in that cooling step relates to can inner, outside or inner, the outside cooling agent that uses simultaneously, and wherein cooling agent can order or used simultaneously.

46. according to the method for claim 39, it is characterized in that raw material comprises that two or more are dissimilar, the material of rank or size, and this method comprises the following steps: also

In shaped device, introduce different materials at preset time;

Obtaining thus can be with the goods of predetermined structure, performance and/or feature formation.

47. according to the method for claim 46, the raw material that it is characterized in that being incorporated in the shaped device is selected from different materials, thus can form have one, two, three, four or the pipeline of more multi-layered different materials or material identical and have the pipeline of different qualities.

48., also comprise step according to the method for claim 39:

Control be loaded into the amount of the different materials in the shaped device, shaped device that control contains described material rotary speed order, the control duration of heat, and control this method in the temperature that each particular step reached, with control goods wall part or the layer even distribution and density.

49. the method according to claim 39 is characterized in that: the mode to eliminate formation sand holes between the particle that forms goods of shaped device is rotated.

50. the method according to claim 39 also comprises the following steps:

The hot briquetting device is to become the feedstock conversion in the shaped device fusion or plastic raw material; With

Using gases is exerted pressure and to the internal pressurization of shaped device, to form product closely, is minimized the sand holes that form in the formed goods thus to fusion or the raw material that is in plastic state facing to the inwall of shaped device.

51. the method according to claim 39 is characterized in that: the speed of the rotation of shaped device is with the variable variable-speed motor that uses but variable.

52. the method according to claim 51 is characterized in that: the rotary speed of control motor comprises so that two stages to be provided:

Slow revolving process, wherein shaped device makes plastic tab rainfall form fall effect on the material in the cylindrical shell with slow relatively speed rotation to reach, next

In the fast rotational stage, the speed that wherein increases the rotation of shaped device makes the particles no longer rainfall, but makes raw material remain on the appropriate location by centripetal force, and this moment, heated particle made the softening and fusing of plastic material, and thin slice solidify to form goods.

53. the method according to claim 39 is characterized in that: goods are with the moulding of overall fixed part, and wherein fixture is in or towards goods one end, or extend along the main body of these goods.

54. the method according to claim 53 is characterized in that, the overall fixed part is flange or the horn mouth section that permission interconnects two goods.

55. the method according to claim 53 is characterized in that: exist to be in or to help by shaped device the goods demoulding towards the fixture of goods one end.

56. the method according to claim 39 is characterized in that: the inwall of this shaped device be have tapering to help by shaped device with the goods demoulding.

57., use among the claim 1-38 each equipment according to each method among the claim 39-56.