A mold for producing a capsule-shaped rubber product, a capsule-shaped rubber product, and a production process

Abstract

This application provides a mold for preparing a bladder-shaped rubber product, a bladder-shaped rubber product, and a manufacturing process. The mold includes a core mold, an upper mold, a middle mold, and a lower mold. During the preparation process, the middle mold surrounds the outside of the core mold and is located between the upper and lower molds. The contact surface between the middle and lower molds is flush with the product opening. A connected cavity is formed between the upper mold, middle mold, lower mold, and core mold. A cavity mold also forms a connected cavity with the middle mold, lower mold, and core mold. The lower mold is connected to the core mold, and the middle mold is fixed between the upper and lower molds. Air holes are provided on the core mold. During the core mold demolding process, the core mold carrying the product is hoisted, and compressed air is used to expand the bladder-shaped rubber product, causing it to expand and detach from the core mold, thus completing the preparation of the bladder-shaped rubber product. This application can smoothly achieve core mold demolding, and no parting line along the product axis will appear on the inner wall of the bladder-shaped rubber product, improving the flexural resistance of the bladder-shaped rubber product.

Description

Technical Field

[0001] This invention relates to the field of rubber product preparation technology, and in particular to a mold for preparing a capsule-shaped rubber product, the capsule-shaped rubber product, and the manufacturing process. Background Technology

[0002] In the chemical industry, buffer tanks are often used to balance system pressure fluctuations and maintain system pressure in emergency situations.

[0003] The buffer tank is installed after the chemical raw material transfer pump. A diaphragm capsule filled with nitrogen is installed inside the buffer tank, and the tank opening is connected to the pipeline. When the pressure increases, the material enters the buffer tank, the gas is compressed, and the system pipeline pressure no longer rises. When the pipeline pressure decreases, the compressed gas inside the capsule expands, forcing the material back into the loop, thereby slowing down the pressure drop. This achieves the purposes of energy storage and pressure maintenance, reduction of pulse vibration, absorption of shocks, and replenishment of liquid, making the system operation more stable, safer, more efficient, and with lower energy consumption.

[0004] The buffer tank body is made of cast steel or forged steel, and the bladder diaphragm is made of rubber. During use, the main cause of failure is bladder rupture. To ensure normal system operation, it is necessary to manufacture a flexible bladder diaphragm with as few parting lines as possible and a long service life.

[0005] However, since capsules are generally small in opening and large in internal dimensions, they are typically manufactured using molds. This involves placing rubber sheets or rolls into the mold cavity and then performing molding and vulcanization processes to create the capsule-shaped product. However, because capsule-shaped products used in buffer tanks have small openings and large internal dimensions, the core mold 3, located inside the rubber diaphragm, is difficult to separate from the capsule during the manufacturing process. Summary of the Invention

[0006] To address the problem that the core mold is difficult to separate from the bladder-shaped rubber product during the manufacturing process, this invention provides a mold for preparing bladder-shaped rubber products, bladder-shaped rubber products, and a manufacturing process.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0008] In a first aspect, this application provides a mold for preparing a capsule-shaped rubber product, wherein the capsule-shaped rubber product has an opening, the diameter of which is smaller than the diameter of the capsule body; the mold includes: a core mold, an upper mold, a middle mold, a lower mold, a material cavity mold, and a plunger;

[0009] During the manufacturing process, the capsule-shaped rubber product has its opening facing downwards; the middle mold surrounds the outside of the core mold and is located between the upper mold and the lower mold; the contact surface between the middle mold and the lower mold is flush with the opening of the product; the upper mold, the middle mold, the lower mold, and the core mold form a connected cavity for manufacturing the capsule-shaped rubber product; the material cavity mold, the middle mold, the lower mold, and the core mold form a connected cavity for injecting rubber during the manufacturing of the capsule-shaped rubber product; the volume of the cavity formed by the material cavity mold, the middle mold, the lower mold, and the core mold is larger than the volume of the cavity formed by the upper mold, the middle mold, the lower mold, and the core mold.

[0010] The lower mold is connected to the core mold, and the middle mold is fixed between the upper mold and the lower mold;

[0011] An air hole is provided on the core mold to guide gas between the core mold and the bladder-shaped rubber product, so as to detach the bladder-shaped rubber product from the core mold.

[0012] Furthermore, the bladder-shaped rubber product is a bladder-shaped rubber product with no opening at the bottom.

[0013] Furthermore, the core mold is an integral structure, and the shape of the core mold is adapted to the internal shape of the bladder-shaped rubber product; air holes are provided on the core mold to inflate the space between the core mold and the bladder-shaped rubber product, thereby separating the bladder-shaped rubber product from the core mold.

[0014] Furthermore, in the mold-closed state, latches are provided on the side walls of the upper mold and the middle mold, and the latches are used to connect and fix the upper mold and the middle mold; a lifting handle is provided on the outer side wall of the middle mold.

[0015] Secondly, this application provides a capsule-shaped rubber product, which is made using the aforementioned mold for preparing the capsule-shaped rubber product.

[0016] Thirdly, when manufacturing a bladder-shaped rubber product with no opening at the bottom, the manufacturing process includes:

[0017] The lower mold and the core mold are assembled and fixed, and adhesive strips are placed at the flange of the product;

[0018] The middle mold and the lower mold are hoisted together. Glue strips are placed in the gap between the middle mold and the core mold, and glue is laid in the cavity of the middle mold.

[0019] Hoist the core mold, prepare the film, lay it on the upper surface of the core mold, hoist the material cavity mold and the middle mold to fit together, load the film roll, hoist the plunger, close the mold and put it on the machine;

[0020] After injection molding, the material cavity mold and plunger are lifted, defects are repaired, the upper mold is hoisted and matched with the middle mold, and then sent into the machine for pressurization, heating and timing vulcanization.

[0021] The machine is depressurized, the mold is pulled out, the middle mold and the upper mold are locked together using the locking buckle, the middle mold is lifted, the mold is rotated 180°, and the mold is placed on the rubber plate.

[0022] Loosen the lock, lift the middle mold, and rotate it 180°.

[0023] The core mold is suspended in mid-air, and air is injected between the core mold and the bladder-shaped rubber product. Under the action of compressed air, the bladder-shaped rubber product is separated from the core mold, resulting in a bladder-shaped rubber product with no opening at the bottom.

[0024] This application provides a mold for preparing a capsule-shaped rubber product, a capsule-shaped rubber product, and a manufacturing process. The mold includes a core mold, an upper mold, a middle mold, and a lower mold. During the preparation process, the capsule-shaped rubber product has an opening facing downwards. The middle mold surrounds the outside of the core mold and is located between the upper mold and the lower mold. The contact surface between the middle mold and the lower mold is flush with the opening. The upper mold, the middle mold, the lower mold, and the core mold form a communicating cavity for preparing the capsule-shaped rubber product. The material cavity mold is connected to the middle mold, the upper mold, the middle mold, and the lower mold. The lower mold and the core mold form a connected cavity for injecting rubber during the preparation of the capsule-shaped rubber product. The cavity volume of the material cavity mold, the middle mold, the lower mold, and the core mold is larger than the cavity volume of the upper mold, the middle mold, the lower mold, and the core mold. The lower mold is connected to the core mold, and the middle mold is fixed between the upper mold and the lower mold. Air holes are provided on the core mold to guide gas between the core mold and the capsule-shaped rubber product, allowing the capsule-shaped rubber product to detach from the core mold. In the core mold demolding process, the upper mold, middle mold, lower mold, and core mold can be separated. The core mold carrying the product is hoisted, and compressed air is used to inflate the capsule-shaped rubber product, causing it to expand and detach from the core mold, thus completing the preparation of the capsule-shaped rubber product. This application can smoothly achieve demolding of the core mold, and there will be no parting line along the product axis on the inner wall of the bladder-shaped rubber product. Under the premise of smooth demolding, the quality of the bladder-shaped rubber product can be ensured. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of a capsule-shaped rubber product according to this embodiment.

[0026] Figure 2 This is a schematic diagram of the structure of a mold for preparing a capsule-shaped rubber product according to this embodiment.

[0027] Figure 3This is a schematic diagram of the disassembled structure of a mold for preparing a capsule-shaped rubber product according to this embodiment.

[0028] Attached reference numerals: 1-Bag-shaped rubber product, 2-Upper mold, 4-Middle mold, 5-Lower mold, 3-Core mold, 6-Lock, 7-Inflation hole, 8-Skeleton lifting hole. Detailed Implementation

[0029] In the chemical industry, buffer tanks are typically used to reduce system pressure fluctuations and maintain system pressure during unplanned shutdowns.

[0030] The buffer tank is installed after the chemical raw material transfer pump. A diaphragm capsule filled with nitrogen is installed inside the buffer tank, and the tank opening is connected to the pipeline. When the pressure increases, material enters the buffer tank, the gas inside the capsule is compressed, and the system pipeline pressure no longer rises. When the pipeline pressure decreases, the compressed gas inside the capsule expands, forcing the material back into the loop, thereby slowing down the pressure drop. This achieves the purposes of energy storage and pressure maintenance, reduction of pulse vibration, absorption of shock, and replenishment of liquid, making the system operation more stable, safer, more efficient, and with lower energy consumption.

[0031] The buffer tank body is made of cast steel or forged steel, and the bladder diaphragm is made of rubber. During use, the main cause of failure is bladder fatigue rupture. To ensure normal system operation, it is necessary to manufacture bladder diaphragms with as few parting lines as possible, long service life, and flexural resistance.

[0032] However, for complex-shaped, thin-walled bladder-like rubber products, conventional molding processes present difficulties, necessitating injection molding. The problem with injection molding is that rubber columns formed during injection can affect usability. Furthermore, due to the bladder's internal structure—a small opening and a large internal dimension—currently, bladder-like rubber products are typically manufactured using molds. This involves placing rubber sheets or rolls into the mold cavity, followed by molding and vulcanization. However, because bladder-like rubber products used in cushioning bladders have a small opening and a large internal dimension, the core mold 3, located inside the rubber diaphragm, is difficult to separate from the bladder during the diaphragm manufacturing process. In other words, due to the fatigue characteristics of bladders—specifically, the integrity of the bladder surface—the core mold 3 and the middle mold should be an integral structure to avoid parting lines on the product surface. However, when the core mold 3 is an integral structure, removing it from the small opening of the bladder becomes problematic.

[0033] In conclusion, the number of parting lines determines the quality of the product.

[0034] To address the aforementioned technical issues, the existing solution involves radially dividing the core mold 3 into multiple small pieces (referred to in the industry as a "seven-petal core mold" structure) to facilitate demolding. During demolding, these small pieces are sequentially extracted from the bladder-shaped rubber product. However, this results in multiple parting lines forming on the inner wall of the bladder-shaped rubber product, severely impacting the product's fatigue life and failing to meet delivery standards. Therefore, it is necessary to minimize the number of parting lines generated on the parting surface and reduce their impact on product quality.

[0035] Based on this, this application proposes the following technical solutions: When manufacturing a bladder-shaped rubber product without holes at the bottom, the core mold 3 of this application is an integral structure. Therefore, there is no parting line on the inner wall of the bladder-shaped rubber product, which can effectively ensure product quality and minimize the impact on product quality, thereby effectively improving product quality. In order to eliminate the glue column after injection, a process method of replacing the upper mold is derived. The problem of insufficient vulcanization pressure caused by replacing the upper mold leads to the mold design where the injection volume is greater than the product volume.

[0036] The following is in conjunction with the appendix Figure 1 - Figure 4 provides a further detailed description of the invention.

[0037] Firstly, see [the following] Figure 1 , Figure 2 , Figure 3 As shown, this application provides a mold for preparing a capsule-shaped rubber product 1. The capsule-shaped rubber product 1 has an opening, the diameter of which is smaller than the diameter of the inner cavity. The mold includes: a core mold 3, an upper mold 2, a middle mold 4, and a lower mold 5. During the preparation process, the opening of the capsule-shaped rubber product 1 faces downward. The middle mold 4 surrounds the outside of the core mold 3 and is located between the upper mold 2 and the lower mold 5. The contact surface between the middle mold 4 and the lower mold 5 is flush with the opening of the product. The core mold 3 forms a communicating cavity with the upper mold 2, the middle mold 4, and the lower mold 5 for preparing the capsule-shaped rubber product 1. The lower mold 5 is connected to the core mold 3, and the middle mold 4 is fixed between the upper mold 2 and the lower mold 5. An air hole 7 is provided on the core mold 3, which is used to guide gas between the core mold 3 and the capsule-shaped rubber product 1 to allow the capsule-shaped rubber product 1 to detach from the core mold 3.

[0038] In this example embodiment, the positioning of the core mold 3 and the lower mold 5 can be achieved by using a positioning pin or a conical surface fit. In specific applications, an air hole 7 can be opened on the core mold 3 to guide compressed air between the core mold 3 and the bladder-shaped rubber product 1, so that the compressed air expands the bladder-shaped rubber product 1, thereby causing the bladder-shaped rubber product 1 to fall off the core mold 3.

[0039] In one specific embodiment, when the bottom of the bladder-shaped rubber product 1 has no opening, the core mold 3 is an integral structure. The shape of the core mold 3 is adapted to the internal shape of the bladder-shaped rubber product 1. An air hole 7 is provided on the core mold 3 to inflate the space between the core mold 3 and the bladder-shaped rubber product 1 through the air hole 7, thereby separating the bladder-shaped rubber product 1 from the core mold 3.

[0040] In one specific embodiment, in the mold-closed state, a latch (6) is provided on the side walls of the lower mold 5 and the middle mold 4. The latch (6) is used to connect and fix the lower mold 5 and the middle mold 4 (to prevent the lower mold from falling off during mold hoisting and flipping); a hoisting handle is provided on the outer side wall of the middle mold 4.

[0041] This application provides a mold for preparing a capsule-shaped rubber product, a capsule-shaped rubber product, and a manufacturing process. The mold includes a core mold 3, an upper mold 2, a middle mold 4, and a lower mold 5. During preparation, the capsule-shaped rubber product 1 has its opening facing downwards. The middle mold 4 surrounds the outside of the core mold 3 and is located between the upper mold 2 and the lower mold 5. The contact surface between the middle mold 4 and the lower mold 5 is flush with the opening of the product. The core mold 3 forms a communicating cavity with the upper mold 2, middle mold 4, and lower mold 5 for preparing the capsule-shaped rubber product 1. The lower mold 5 is connected to the core mold 3, and the middle mold 4 cooperates with the upper mold 2 and the lower mold 5. An air hole 7 is provided on the core mold 3 to guide gas between the core mold 3 and the capsule-shaped rubber product 1, allowing the capsule-shaped rubber product 1 to detach from the core mold 3. During the demolding process of the core mold 3, the core mold 3 can be pre-lifted, and compressed air can be used to expand the bladder-shaped rubber product, causing the bladder-shaped rubber product to expand and detach from the core mold 3, thereby completing the preparation of the bladder-shaped rubber product 1. This application can smoothly achieve the demolding of the core mold 3, and no parting strips along the product height direction will appear on the inner wall of the bladder-shaped rubber product 1, ensuring the fatigue characteristics of the bladder-shaped rubber product 1 while ensuring smooth demolding.

[0042] Secondly, this application provides a capsule-shaped rubber product, which is manufactured using the same mold as the capsule-shaped rubber product 1 described above. See also... Figure 1 As shown, Figure 1 A capsule-shaped rubber product 1 without an opening at the bottom is provided, wherein the internal dimensions are larger than the opening dimensions, and the surface has fewer parting lines.

[0043] Thirdly, this application provides a manufacturing process for a bladder-shaped rubber product. When manufacturing a bladder-shaped rubber product 1 with no opening at the bottom, the manufacturing process includes: step S210-step S280.

[0044] Step S210. Assemble and connect the lower mold 5 and the core mold 3, and place a rubber strip at the product opening.

[0045] Step S220. Hoist the middle mold 4 and lower mold 5 together, arrange the rubber strip in the gap between the middle mold 4 and the core mold 3, and lay the rubber in the cavity of the middle mold 4.

[0046] Step S230. Hoist the core mold 3.

[0047] Step S240. Prepare the film, place it on the core mold 3, install the lifting and pressing cavity in place, load the film roll, lift the pressing head, close the mold and put it on the machine.

[0048] Step S250. Pressurize the machine. After completion, lift the pressure chamber and pressure head, repair defects and fill with glue, lift the upper mold 2 and middle mold 4 to match, send it into the machine, pressurize and heat, and start the vulcanization timer.

[0049] Step S260. Depressurize the machine, pull out the mold, lock the middle mold 4 and the upper mold 2, lift the middle mold 4, rotate the mold 180°, and place the mold on the rubber plate.

[0050] Step S270. Loosen the lock and lift the middle mold 4.

[0051] Step S280. Install the lifting ring and inflation nozzle, suspend the core mold 3 in the air, connect the air duct and force-cool it for 30-40 minutes. Inflate the space between the core mold 3 and the bladder-shaped rubber product 1 slowly to expand the product, then drop the product to allow the silicone oil to fully disperse. Repeat this process several times, then slowly inflate again, using an inflate-stop, inflate-stop method to allow the product to be smoothly released. A bladder-shaped rubber product 1 with no openings at the bottom is obtained.

[0052] Specifically, taking an air-filled capsule as an example, the technical solution of this application will be further described in detail, as shown in Figure 4, which illustrates the air-filled capsule of this application. The specific steps are as follows, including steps 1-3:

[0053] 1. Position the skeleton onto the core mold 3 using screws. First, install the rubber strip at the opening, then apply adhesive to the cavity of the middle mold 4, and then apply adhesive to the upper surface of the core mold 3. Lift the core mold 3 and install it inside the mold. Ensure that the core mold 3 is fully installed. If it is not installed, slightly lift the core mold 3, adjust its direction, and reinstall it until it is in place.

[0054] 2. Injection and Vulcanization: Load the preheated film into the injection chamber, install the pre-tension spring, and inject pressure after closing the mold. Observe the pressure gauge during injection; release pressure when the pressure does not drop, and clean the injection chamber. First, pry the press head with a pry bar, then lift the press head, clean the residual glue with a putty knife, and weigh it to calculate the total glue volume. The total glue volume should be controlled at around 9.2 kg. If the glue volume is insufficient, perform a second injection. Match the press head with the injection chamber, then pry the injection chamber again, and then lift the press head and injection chamber together. Above the mold seam on the outside of the glue column, use a needle to prick a row of air holes to ensure unobstructed air passage. Then cut the glue column, puncture any air bubbles, and add glue. Then add a thick film of about Φ250 mm in the center of the product. Lift the upper mold 2, close the mold and put it on the machine. Perform back pressure and air release 3 times, and start timing for vulcanization.

[0055] 3. Demolding. The demolding process includes steps A through D.

[0056] A. Depressurize and pull out the mold. Install the locking buckle to lock the middle mold 4 and the upper mold 2 to prevent them from falling off during flipping.

[0057] B. Pry open the middle mold 4 and the lower mold 5, lift the middle mold 4 together with the core mold 3 and the upper mold 2, place it on the fixture and rotate it 180°, place it on the bracket, remove the lock (6), slowly lift the middle mold, be careful not to lift the product and the core mold 3, rotate it again, and cooperate with the lower mold 5.

[0058] C. Install lifting rings on core mold 3 to lift core mold 3 and separate it from upper mold 2. After cooling the neck and opening of the product with water for 8-10 minutes, apply silicone oil between core mold 3 and the product to form a uniform oil film. Install lifting rings and air inlet, connect air ducts, and force-cool the product by blowing air for 30-40 minutes.

[0059] D. Slowly inflate the product to make it expand, then drop the product to allow the silicone oil to disperse fully. Repeat this process several times, then slowly inflate again, using an inflate-stop, inflate-stop method to allow the product to be successfully removed.

[0060] This specific embodiment is merely an explanation of the invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but as long as they are within the scope of protection of this invention, they are protected by patent law.

Claims

1. A mold for preparing a capsule-shaped rubber product, wherein the capsule-shaped rubber product (1) has an opening, the diameter of which is smaller than the diameter of the capsule body; characterized in that, The mold includes: Core mold (3), upper mold (2), middle mold (4), lower mold (5), material cavity mold and plunger; During the preparation process, the capsule-shaped rubber product (1) has its opening facing downwards; the middle mold (4) surrounds the outside of the core mold (3), and the middle mold (4) is located between the upper mold (2) and the lower mold (5); the contact surface between the middle mold and the lower mold is flush with the opening; the upper mold (2) forms a connected cavity with the middle mold (4), the lower mold (5), and the core mold (3) for preparing the capsule-shaped rubber product (1); The shape of the cavity mold is adapted to the shape of the bladder-shaped rubber product. The cavity mold cooperates with the middle mold (4) to press the plunger onto the bladder-shaped rubber product. The cavity mold, the middle mold (4), the lower mold (5), and the core mold (3) form a connected cavity for injecting glue when preparing the bladder-shaped rubber product. The cavity volume formed by the cavity mold, the middle mold (4), the lower mold (5), and the core mold (3) is larger than the cavity volume formed by the upper mold (2), the middle mold (4), the lower mold (5), and the core mold (3). In the mold-closed state, a latch (6) is provided on the side wall of the upper mold (2) and the middle mold (4), and the latch (6) is used to connect and fix the lower mold (5) and the middle mold (4); a lifting handle is provided on the outer side wall of the middle mold (4); The lower mold (5) is connected to the core mold (3), and the middle mold (4) is fixed between the upper mold (2) and the lower mold (5); An air hole (7) is provided on the core mold (3). The air hole (7) is used to guide gas between the core mold (3) and the bladder-shaped rubber product (1) so as to detach the bladder-shaped rubber product (1) from the core mold (3).

2. The mold for preparing the capsule-shaped rubber product according to claim 1, characterized in that, The bladder-shaped rubber product (1) is a bladder-shaped rubber product (1) without openings at the bottom.

3. The mold for preparing the capsule-shaped rubber product according to claim 1, characterized in that, The core mold (3) is an integral structure, and the shape of the core mold (3) is adapted to the internal shape of the bladder-shaped rubber product (1).

4. A manufacturing process for a capsule-shaped rubber product, applied to the preparation mold of the capsule-shaped rubber product according to any one of claims 1-3, characterized in that, When manufacturing a bladder-shaped rubber product (1) that has no opening at the bottom, the manufacturing process includes: The lower mold (5) and the core mold (3) are assembled and fixed, and adhesive strips are placed at the flange of the product; The middle mold (4) is hoisted and matched with the lower mold (5). Glue strips are arranged in the gap between the middle mold (4) and the core mold (3), and glue is laid in the cavity of the middle mold (4). The core mold (3) is connected to the product skeleton by bolts. The lifting hole (8) of the hoisting skeleton, together with the core mold (3), is matched with the lower mold (5). The film is prepared and placed on the upper surface of the core mold (3). The hoisting cavity mold is matched with the middle mold (4), the film is loaded, the plunger is hoisted, and the mold is closed and put on the machine. Pressurize the machine, lift the material cavity mold and plunger after completion, repair defects, lift the upper mold (2) and middle mold (4) to match, send into the machine, pressurize, heat and vulcanize for time; The machine is depressurized, the mold is pulled out, the middle mold (4) is locked to the upper mold (2) using the lock (6), the middle mold (4) is lifted, the mold is rotated 180°, and the mold is placed on the rubber plate. Release the lock (6), lift the middle mold (4), so that the middle mold (4) separates from the core mold (3); The core mold (3) is lifted and suspended in the air. Air is injected between the core mold (3) and the bladder rubber product (1). Under the action of compressed air, the bladder rubber product (1) is separated from the core mold (3), and a bladder rubber product (1) with no opening at the bottom is obtained.

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