CN111720555A - Composite water-stopping rubber sealing ring - Google Patents

Abstract

The invention discloses a composite water-stopping rubber sealing ring, which relates to the technical field of rubber sealing rings; the common rubber and the expanded rubber are integrally formed through mould pressing, two sides of the expanded rubber and the common rubber are fixed to form a large dovetail groove and a small dovetail groove, a convex peak is fixedly arranged on the common rubber, the large dovetail groove part of the common rubber is made of expanded rubber materials, the section of the common rubber is basically in an R shape, the common rubber integrates three functions of elasticity, a V shape and water stopping of a water-swelling rubber sealing ring, the pipeline joint not only stops water in a single-peak shape and a large dovetail groove, but also increases the water-swelling function of the rubber, and triple guarantee is achieved; the water-stopping service life is long, the rubber ring is expanded when meeting water slowly, and the water-stopping rubber ring is similar to the function of stapling a wooden wedge, so that the water-stopping effect is better and the water-stopping rubber ring is more suitable for installation.

Description

Composite water-stopping rubber sealing ring

Technical Field

The invention belongs to the technical field of rubber sealing rings, and particularly relates to a composite water-stopping rubber sealing ring.

Background

The rubber ring sealing material is widely applied to fittings of joints of agricultural irrigation pipelines, rural safe drinking water pipelines, municipal works, industrial and mining enterprises and petrochemical engineering water delivery and drainage pipelines, and is suitable for rubber ring sealing products for joints of water supply pipelines, water drainage pipelines and sewage pipelines of plastic pipes such as PVC-U, PVC-C, PVC-M, PVC-O and the like. For a pipeline interface with a large caliber; the pipe wall is relatively thin, the nominal pressure is 0.4MPa and the pipe interface of the 0.63MPa grade (the size ratio SDR is less than 70); the pipeline with serious water leakage under the condition of low pressure and negative pressure of the connector; particularly, the water-stopping effect is good when the PVC-M pipeline interface with large flexibility and the like are used.

Disclosure of Invention

Aiming at solving the problems of the defects and the shortcomings of the prior art; the invention aims to provide a composite water-stopping rubber sealing ring which is simple in structure, reasonable in design and convenient to use, the section of the composite water-stopping rubber sealing ring is basically in an R shape by using an expansion rubber material at a large dovetail groove part of common rubber, the composite water-stopping rubber sealing ring integrates three functions of elasticity, V shape and water stopping of the water-swelling rubber sealing ring, a pipeline joint not only stops water in a single-peak and large dovetail grooves, but also increases the water-swelling function of rubber, and triple guarantee is achieved; the water-stopping service life is long, the rubber ring is expanded when meeting water slowly, and the water-stopping rubber ring is similar to the function of stapling a wooden wedge, so that the water-stopping effect is better and the water-stopping rubber ring is more suitable for installation.

In order to achieve the purpose, the invention adopts the technical scheme that: the rubber comprises common rubber, expanded rubber, a large dovetail groove, a small dovetail groove and a convex peak; the general rubber and the expansion rubber are integrally formed through mould pressing, two sides of the expansion rubber and the general rubber are fixed to form a large dovetail groove and a small dovetail groove, and the general rubber is fixedly provided with convex peaks.

Preferably, the common rubber is ethylene propylene diene monomer rubber, and the ethylene propylene diene monomer rubber is prepared from the following raw materials in parts by weight: 80-120 parts of natural rubber, 1-10 parts of zinc oxide, 0.1-1 part of stearic acid, 0.5-2 parts of anti-aging agent D, 5-20 parts of semi-reinforcing furnace black, 1-5 parts of operating oil, 1-5 parts of accelerator TMTD and 0.1-0.5 part of sulfur.

Preferably, the expanded rubber is prepared from the following raw materials in parts by weight: 80-120 parts of natural rubber, 1-10 parts of zinc oxide, 0.5-3 parts of stearic acid, 0.5-10 parts of antioxidant D1, 0.5-5 parts of magnesium oxide, 40100.5-5 parts of antioxidant, 1-5 parts of paraffin, 30-70 parts of semi-reinforcing furnace black, 10-20 parts of dibutyl sebacate and 0.5-5 parts of accelerator DM.

Preferably, the specific processing flow is as follows:

plasticating: drying the domestic standard No. one glue in an oven at 50-80 deg.C, and cutting. Rubber mixing is carried out, a machine is checked firstly, then the machine is started to preheat, the temperature is controlled to be about 150 ℃, the plug pressure is 0.3-0.8MPa, and all auxiliary agents except the accelerant TMTD and sulfur are added to plasticate the raw rubber for 10-20 minutes;

(II) mixing: standing the crude rubber for 5-10h, and adding sulfur and an accelerant for mixing, so that the physical and mechanical properties of the auxiliary agent can be enhanced and the processing performance is good;

(III) mould pressing and vulcanizing: opening a flat vulcanizing machine to preheat for half an hour, preheating the mold to a set temperature, taking out the mold to open, coating silicon oil on the inner side of the mold, shearing a proper amount of mixed natural rubber material, putting the mixed natural rubber material into the mold, molding the product at the set pressure of 8-12MPa, the vulcanization temperature of 120 ℃ and 180 ℃, and the vulcanization time of 2-8 min. Vulcanization is carried out simultaneously with molding. Finally taking out the product

(IV) secondary forming: and after the product is cooled, placing the natural rubber ring rubber into a second set of mold, adding the expanded rubber material, performing mold pressing on the product in the mold, setting the pressure to be 8-12MPa, the vulcanization temperature to be 120-.

Compared with the prior art, the invention has the beneficial effects that: the invention uses the expanded rubber material to make in the big dovetail groove part of the common rubber, make its section basically present "R" shape (form of the double dovetail groove), place the rubber ring position size design according to the plastic pipe flaring, collect elasticity (self-force), "V" shape (double dovetail groove), three major functions of the water stopping of the water-swelling rubber seal ring of water-swelling are an organic whole, the pipeline junction is not merely unimodal (little dovetail groove part), big dovetail groove water stopping (greater than the medium pressure), increased the water-swelling function of rubber, have accomplished the triple guarantee; the water-stopping service life is long, and the compression deformation rate is less than or equal to 25 percent; the Shore hardness is controlled to be about 50 degrees, and the construction and installation are easy; the rubber ring is expanded slowly when meeting water, the filling degree is increased by more than 30% compared with the conventional method under the action similar to the action of binding a wooden wedge, and the influences of insufficient deformation rate, excessive permanent deformation rate (less than 10%) and displacement (thickness change) are compensated, so that the water-stopping effect is better and the water-stopping device is more suitable for installation.

Drawings

For ease of illustration, the invention is described in detail by the following detailed description and the accompanying drawings.

FIG. 1 is a schematic structural view of the present invention;

fig. 2 is a cross-sectional view of the present invention installed in a flare of a plastic tube.

In the figure: the rubber comprises common rubber 1, expanded rubber 2, a large dovetail groove 3, a small dovetail groove 4, a convex peak 5, a deformation contour line 6 and a solid contour line 7.

Detailed Description

In order that the objects, aspects and advantages of the invention will become more apparent, the invention will be described by way of example only, and in connection with the accompanying drawings. It is to be understood that such description is merely illustrative and not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

It should be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and/or processing steps closely related to the scheme according to the present invention are shown in the drawings, and other details not so relevant to the present invention are omitted.

As shown in fig. 1, the following technical solutions are adopted in the present embodiment: the rubber comprises common rubber 1, expanded rubber 2, a large dovetail groove 3, a small dovetail groove 4 and a convex peak 5; the novel rubber dovetail groove is characterized in that the common rubber 1 and the expanded rubber 2 are integrally formed through die pressing, two sides of the expanded rubber 2 are fixed with the common rubber 1 to form a large dovetail groove 3 and a small dovetail groove 4, and the common rubber 1 is fixedly provided with a convex peak 5.

As shown in fig. 2, the present invention is installed in the plastic pipe flare, which is deformed from a deformed contour line 6 to a solid contour line 7, and an elastic water stop area a and a dovetail water stop area B are effectively formed in the plastic pipe flare.

Example (b):

firstly, 100 parts of natural rubber is selected to be dried in an oven, the drying temperature is 55 ℃, and then the rubber is cut by a rubber cutting machine. Rubber mixing is carried out, a machine is checked firstly, then the machine is started to preheat, the temperature is controlled to be about 150 ℃, the plug pressure is 0.5MPa, and then 5 parts of zinc oxide, 0.5 part of stearic acid, 1 parts of anti-aging agent D, 10 parts of semi-reinforcing furnace black and 3 parts of operating oil are added to plasticate raw rubber for 13 minutes; standing the crude rubber for 8 hours, and then adding 3 parts of promoter TMTD and 0.25 part of sulfur for mixing, so that the physical and mechanical properties of the uniformly mixed auxiliaries are enhanced, and the technological properties are good; opening a flat vulcanizing machine to preheat for half an hour, preheating the mold to a set temperature, taking out the mold to open, coating silicon oil on the inner side of the mold, shearing a proper amount of mixed natural rubber material, putting the mixed natural rubber material into the mold, and carrying out mold pressing on a product at the set pressure of 10MPa, the vulcanization temperature of 145 ℃ and the vulcanization time of 5 min. Vulcanization is carried out simultaneously with molding. Finally, preparing a natural rubber ring;

and secondly, selecting 100 parts of natural rubber to be dried in an oven, wherein the drying temperature is 55 ℃, and then cutting the rubber by a rubber cutting machine. Rubber mixing is carried out, a machine is checked firstly, then the machine is started to preheat, the temperature is controlled to be about 150 ℃, the top plug pressure is 0.5MPa, and then 8 parts of zinc oxide, 1 part of stearic acid, 4 parts of anti-aging agent D, 1.5 parts of magnesium oxide, 40101.5 parts of anti-aging agent, 2 parts of paraffin, 57.5 parts of semi-reinforcing furnace black and 18.3 parts of dibutyl sebacate are added to plasticate the raw rubber for 13 minutes; standing the raw rubber for 8 hours, adding 1 part of an accelerant DM, and mixing to prepare a rubber material after the expanded rubber is mixed;

and after the product is cooled, placing the natural rubber ring into a second set of die, adding the rubber material mixed by the expanded rubber, carrying out die pressing on the product in the die with the set pressure of 10MPa, the vulcanization temperature of 145 ℃ and the vulcanization time of 3min, carrying out die pressing again by a self-crosslinking process, and automatically crosslinking the expanded rubber and the common rubber to obtain the final product.

The equipment and the die used in the above embodiment:

1. internal mixer

a. Main technical parameters

The speed and speed ratio of the rotor; the edge ratio of the rotor is equal to the gap of the inner wall of the mixing chamber; capacity and fill factor; the unit pressure of the upper top bolt on the rubber material; and (4) power.

The manufacturer: tin-free Bixiang rubber-plastic machinery Co Ltd

The model is as follows: x (S) N-35/30

b. Factors influencing the mixing effect of internal mixer

Mixing capacity: insufficient mixing capacity can reduce the shearing action and kneading action on the rubber material, and even the phenomena of rubber material slipping and rotor idling occur, so that the mixing effect is poor. On the contrary, the rubber material is difficult to turn over due to overlarge capacity, so that the upper top bolt is not in proper position, and a part of the rubber material is retained at the neck of the feeding port, so that the rubber material is not uniformly mixed, the mixing time is long, equipment overload is easily caused, and the energy consumption is high.

Secondly, the charging sequence: generally, raw rubber is added firstly, then carbon black is added, and after the carbon black is basically dispersed in rubber material by mixing, the liquid softener is added, so that the mixing is facilitated, the mixing effect is improved, and the mixing time is shortened. The liquid softener is added too early or too late, which is unfavorable for mixing, easily causes uneven dispersion, prolongs mixing time and increases energy consumption. Sulfur and an accelerator are usually added at the latter stage of kneading, and small drugs (solid softeners, activators, accelerators, anti-aging agents, scorch retarders, etc.) are usually added after the raw rubber and before the carbon black.

Thirdly, the upper top bolt pressure: when the internal mixer is used for mixing, the rubber material must be subjected to a certain pressure of the upper plug. The upper plug pressure is preferably 0.3 to 0.6 MPa. When the rotor speed is constant, the effect of further increasing the pressure is also not great. When the kneading capacity is insufficient, the upper plug pressure does not sufficiently act. Increasing the upper plug pressure reduces the unfilled space in the closed chamber, increasing its fill level by about 10%. As capacity and speed increase, the upper plug pressure must be increased.

The increased upper ram pressure accelerates heat generation in the rubber during mixing and increases power consumption during mixing.

Rotor structure and type

The geometry and dimensions of the working surfaces of the rotors determine to a large extent the throughput and mixing quality of the internal mixer. The basic configuration of the rotor of the internal mixer is of two types: shear type rotors and meshing type rotors. Generally speaking, the shear type rotor internal mixer has higher production efficiency and can quickly feed, quickly mix and quickly discharge rubber. The meshed rotor internal mixer has the characteristics of high dispersion efficiency, low heat generation rate and the like, and is suitable for manufacturing hard rubber materials and mixing in one section. The dispersion and homogenization effect of the meshed rotor internal mixer is better than that of a shearing rotor internal mixer, and the mixing time can be shortened by 30-50%.

Rotating speed: increasing the speed of the rotor of the internal mixer is one of the most effective measures to enhance the mixing process. The rotating speed is doubled, and the mixing period is shortened by about 30-50%. Increasing the rotational speed accelerates heat generation, which leads to a decrease in the viscosity of the sizing material, a decrease in the mechanical shearing effect and a disadvantage in dispersion.

Sixthly, mixing temperature: the high mixing temperature is beneficial to the plastic flow and deformation of raw rubber and rubber materials, is beneficial to the wetting and mixed powder eating of rubber on the surfaces of solid compounding agent particles, but reduces the viscosity of the rubber materials, and is not beneficial to the crushing, dispersion and mixing of the compounding agent particles. When the mixing temperature is too high, the thermal-oxidative aging of rubber can be accelerated, so that the physical and mechanical properties of vulcanized rubber are reduced, namely, the phenomenon of over-mixing occurs; the rubber material can be burnt, so effective cooling measures must be adopted in the mixing process of the internal mixer; but not too low, otherwise the compound will collapse.

And mixing time is as follows: the mixing time required for mixing the rubber compound with an internal mixer under the same conditions is much shorter than that of an open mill. The mixing quality requirement is constant, and the required mixing time is shortened as the rotating speed of the internal mixer and the pressure of the upper ram are increased. Improper charging sequence and improper mixing operation can prolong the mixing time. Extending the mixing time increases the dispersion of the compounding ingredients in the compound, but also decreases the production efficiency. Too long mixing time easily causes the over-mixing of the rubber compound to damage the physical and mechanical properties of the vulcanized rubber, and also causes the increase of the heat history of the rubber compound to easily cause the scorching phenomenon, so the mixing time of the rubber compound is shortened as much as possible.

(II) plate vulcanizing machine

a. Technical parameters

Equipment manufacturers: qingdao Shengdong oak Co Ltd

The equipment model is as follows: QLB-D/Q600X 2

The main technical parameters are as follows:

b. the meaning of the principal parameters

The main technical parameters of the plate vulcanizing machine include nominal pressure, unit area pressure of the hot plates, the number and specification of the layers of the hot plates, the distance between the hot plates, the lifting speed of the hot plates and the like. The nominal pressure of the vulcanizing press is expressed by multiplying the pressure of the working medium by the sectional area of the plunger or the piston, and the influence of the mass of the plunger or the piston, the movable platform, the hot plate and other parts, the friction loss of the sealing device when the plunger or the piston moves and the like is not considered. The nominal pressure is different from the actual pressure and is generally greater than the actual operating pressure. Nominal pressure is usually used as one of the main performance parameters in the design specifications, product samples. The pressure of the hot plate unit area of the flat vulcanizing machine of the model product is related to the vulcanization process of the rubber product, and the value of the pressure depends on the performance of the rubber material, the product structure, the process conditions and the like. The mold is easy to automatically push out and open by the hot plate layer number and hot plate distance model product vulcanizing machine, and rubber materials are conveniently taken out and put in. Equipment beyond two levels typically adds an operating movable table to facilitate loading and unloading of the mold. The platen pitch of the molded article press is generally in the range of 75 to 250 mm. The press vulcanizer selected for this time is 125 mm. The lifting speed of the hot plate influences the production speed of the machine, and particularly the mold opening descending speed is particularly important for a flat vulcanizing machine for molded products. Generally, the rising speed of the molded article vulcanizer is not less than 0.72 m/min. Sometimes, in order to improve the production efficiency, an auxiliary injection cylinder can be used for realizing double-speed lifting. In the case of the cylinder type press vulcanizer for molded products, the lowering of the hot plate is generally performed by removing the liquid from the cylinder by the weight of the movable member, and therefore the speed is slower than that at the time of raising. If the descending speed of the hot plate is increased, a double-acting working cylinder or a return cylinder is additionally arranged.

Compression molding major defect and method for adjusting same

The working principle of the specific embodiment is as follows: the invention is made by compounding common ethylene propylene diene monomer (EP-DM) material and water-swelling rubber without mixing reclaimed rubber. The modified ethylene propylene diene monomer material has excellent aging resistance; the chemical stability is good; excellent compression permanent deformation resistance and compression stress relaxation resistance; the elasticity is high; the service life is more than 50 years longer than the value of the pipe; the application temperature range is-40 to 60 ℃. The expansion rubber dovetail part is made of a standard type 1 material, has the effect of stopping water with water when immersed in water, has a slow expansion speed, increases the volume expansion rate by 150% within 186h of immersion in water, basically reaches more than 90% within 12 h, has a clean and flat surface and is bubble-free; the tensile strength is more than or equal to 2 MPa; the elongation at break is more than or equal to 250 percent. Outstanding elasticity, abrasion resistance, aging resistance and tear resistance, and repeated use is a major advantage.

The product of the invention has simple and convenient installation, low requirement on construction technology and no need of special equipment and power supply; the influence of weather conditions is small, and the pressure test is carried out after the pipeline is installed and water is introduced (soaked) for 16 hours. Because the rubber part which slowly expands when meeting water is added in the product manufacturing process, the Shore hardness can be controlled to be more than or equal to 45, the installation is more free, but the waterproof problem before the installation is noticed.

The related technical indexes of the product are according to GB/T10002.1 hard polyvinyl chloride (PVC-U) pipes for water supply; GB/T13664 hard polyvinyl chloride (PVC-U) pipe for low-pressure water delivery irrigation; GB/T32018.1 impact-resistant modified polyvinyl chloride (PVC-M) pipe for water supply part 1 pipe; GB/T32018.2 impact-resistant modified polyvinyl chloride (PVC-M) pipe system part 2 for water supply; CJ/T272 impact modified polyvinyl chloride (PVC-M) pipe and pipe fitting for water supply; CJJ101 technical Specification for buried plastic water supply pipeline engineering; GB/T21873 Specification for sealing ring materials of interfaces for rubber sealing parts for water supply pipes, water discharge pipes and sewage pipelines; GB/T18173.3 part 3 of waterproof Polymer Material: the water-swellable rubber and other standard specifications.

The product detection test is carried out according to GB/T21873 Specification of sealing ring materials for interfaces of rubber sealing parts for water supply pipes, water discharge pipes and sewage pipelines; GB/T18173.3 part 3 of waterproof Polymer Material: water-swellable rubber GB/T19471.1 test method for sealing deflection angle of hard polyvinyl chloride (PVC-U) pipe elastic sealing ring type bellmouth joint of plastic pipe system; GB/T19471.2 negative pressure sealing test method for rigid polyvinyl chloride (PVC-U) pipe elastic sealing ring type socket joint of plastic pipeline system; wherein, the indexes of partial checking times and interval time are more than specified values in the standard.

Compared with the prior art, the beneficial effects of the embodiment are as follows: the invention uses the expanded rubber material to make in the big dovetail groove part of the common rubber, make its section basically present "R" shape (form of the double dovetail groove), place the rubber ring position size design according to the plastic pipe flaring, collect elasticity (self-force), "V" shape (double dovetail groove), three major functions of the water stopping of the water-swelling rubber seal ring of water-swelling are an organic whole, the pipeline junction is not merely unimodal (little dovetail groove part), big dovetail groove water stopping (greater than the medium pressure), increased the water-swelling function of rubber, have accomplished the triple guarantee; the water-stopping service life is long, and the compression deformation rate is less than or equal to 25 percent; the Shore hardness is controlled to be about 50 degrees, and the construction and installation are easy; the rubber ring is expanded slowly when meeting water, the filling degree is increased by more than 30% compared with the conventional method under the action similar to the action of binding a wooden wedge, and the influences of insufficient deformation rate, excessive permanent deformation rate (less than 10%) and displacement (thickness change) are compensated, so that the water-stopping effect is better and the water-stopping device is more suitable for installation.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims (4)

1. The utility model provides a compound stagnant water rubber seal, its characterized in that: the rubber comprises common rubber (1), expanded rubber (2), a large dovetail groove (3), a small dovetail groove (4) and a convex peak (5); ordinary rubber (1) and expanded rubber (2) are through mould pressing integrated into one piece, big dovetail (3) and little dovetail (4) are fixed to constitute with ordinary rubber (1) to the both sides of expanded rubber (2), fixed hump (5) that are provided with on ordinary rubber (1).

2. The composite water stop rubber sealing ring according to claim 1, characterized in that: the common rubber (1) is ethylene propylene diene monomer rubber which is prepared from the following raw materials in parts by weight: 80-120 parts of natural rubber, 1-10 parts of zinc oxide, 0.1-1 part of stearic acid, 0.5-2 parts of anti-aging agent D, 5-20 parts of semi-reinforcing furnace black, 1-5 parts of operating oil, 1-5 parts of accelerator TMTD and 0.1-0.5 part of sulfur.

3. The composite water stop rubber sealing ring according to claim 1, characterized in that: the expanded rubber (2) is prepared from the following raw materials in parts by weight: 80-120 parts of natural rubber, 1-10 parts of zinc oxide, 0.5-3 parts of stearic acid, 1-10 parts of antioxidant D, 0.5-5 parts of magnesium oxide, 40100.5-5 parts of antioxidant, 1-5 parts of paraffin, 30-70 parts of semi-reinforcing furnace black, 10-20 parts of dibutyl sebacate and 0.5-5 parts of accelerator DM.

4. The composite water stop rubber sealing ring according to claim 1, characterized in that: the specific processing flow is as follows:

plasticating: drying the domestic standard No. one glue in an oven at 50-80 deg.C, and cutting. Rubber mixing is carried out, a machine is checked firstly, then the machine is started to preheat, the temperature is controlled to be about 150 ℃, the plug pressure is 0.3-0.8MPa, and all auxiliary agents except the accelerant TMTD and sulfur are added to plasticate the raw rubber for 10-20 minutes;

(II) mixing: standing the crude rubber for 5-10h, and adding sulfur and an accelerant for mixing, so that the physical and mechanical properties of the auxiliary agent can be enhanced and the processing performance is good;

(III) mould pressing and vulcanizing: opening a flat vulcanizing machine to preheat for half an hour, preheating the mold to a set temperature, taking out the mold to open, coating silicon oil on the inner side of the mold, shearing a proper amount of mixed natural rubber material, putting the mixed natural rubber material into the mold, molding the product at the set pressure of 8-12MPa, the vulcanization temperature of 120 ℃ and 180 ℃, and the vulcanization time of 2-8 min. Vulcanization is carried out simultaneously with molding. Finally taking out the product

(IV) secondary forming: and after the product is cooled, placing the natural rubber ring rubber into a second set of mold, adding the expanded rubber material, performing mold pressing on the product in the mold, setting the pressure to be 8-12MPa, the vulcanization temperature to be 120-.

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