阅读说明：本技术 一种钢衬四氟弯头模压工艺 (Die pressing process for steel lining PTFE elbow ) 是由 王奇 唐金梅 于 2020-06-19 设计创作，主要内容包括：本发明公开了一种钢衬四氟弯头模压工艺,包括以下制备步骤：混合聚四氟乙烯粉末、二氧化硅粉末,聚四氟乙烯粉末占92％—96％,二氧化硅粉末占4％—8％；在100-120℃下,恒温搅拌15min；胶皮袋放于钢制弯头内部,开口端板、封闭端板锁合；注入四氟混合粉末,钢制弯头振动,振动频率为300次/min,振动幅度在2mm以内,将螺旋塞旋入进料管的螺纹内,胶皮袋内注入高压水,胶皮袋膨胀挤压四氟混合粉末成型,将钢制弯头放入烘箱烧结成型后的四氟混合粉末,冷却定型,修理毛边,获得成品。本发明的抗腐蚀性能、强度、耐磨性更强,减少人工参与,提高产品质量,避免操作人员职业病的发生,同时提高了工作效率,减少成品时间。(The invention discloses a die pressing process for a steel lining tetrafluoro bend, which comprises the following preparation steps: mixing polytetrafluoroethylene powder and silicon dioxide powder, wherein the polytetrafluoroethylene powder accounts for 92% -96%, and the silicon dioxide powder accounts for 4% -8%; stirring at 100-120 deg.C for 15 min; the rubber bag is placed inside the steel elbow, and the opening end plate and the closed end plate are locked; injecting the PTFE mixed powder, vibrating a steel elbow with the vibration frequency of 300 times/min and the vibration amplitude within 2mm, screwing a screw plug into the thread of the feeding pipe, injecting high-pressure water into the rubber bag, expanding and extruding the PTFE mixed powder for molding by the rubber bag, putting the steel elbow into the PTFE mixed powder after sintering and molding in an oven, cooling and molding, and repairing burrs to obtain a finished product. The invention has stronger corrosion resistance, strength and wear resistance, reduces the manual participation, improves the product quality, avoids the occupational disease of operators, improves the working efficiency and reduces the finished product time.)

1. A steel lining tetrafluoro bend die pressing process comprises the following preparation steps:

1) weighing high-density polytetrafluoroethylene powder and silicon dioxide powder, and putting the high-density polytetrafluoroethylene powder and the silicon dioxide powder into a mixer, wherein the polytetrafluoroethylene powder accounts for 92% -96% and the silicon dioxide powder accounts for 4% -8% in percentage by mass; uniformly mixing, stirring at constant temperature of 100-120 ℃ for 15min, and cooling to normal temperature to prepare tetrafluoro mixed powder (4);

2) placing the part with larger curvature of the steel elbow (3) on a vibration frame (1), wherein two flanges (11) are respectively arranged obliquely upwards, a notch matched with the side wall of the steel elbow (3) is formed in the vibration frame (1), and the steel elbow (3) is fixed by a hoop (10);

3) the rubber bag (6) is placed inside the steel elbow (3), the rubber bag (6) is in a long tube shape and is provided with only one opening, the two flanges (11) are respectively locked with the opening end plate (5) and the closed end plate (8) through bolts, the opening part of the rubber bag (6) penetrates through the round hole of the opening end plate (5) to extend out,

4) the pipeline of the powder feeder is communicated with a feeding pipe (7) on the opening end plate (5) and the closed end plate (8), and the tetrafluoro mixed powder (4) is injected between the rubber bag (6) and the steel elbow (3); simultaneously starting a vibration motor (2) on the vibration frame (1), wherein the vibration frequency is 300 times/min, and the vibration amplitude is within 2mm, so that the tetrafluoro mixed powder (4) is fully filled;

5) stopping injecting the tetrafluoro mixed powder (4) when the injected tetrafluoro mixed powder (4) reaches 80% of the specified weight, continuing vibrating for 5 minutes, and then injecting the rest 20%;

6) after the material injection is finished, stopping vibration, screwing the spiral plug (9) into the thread of the feeding pipe (7), injecting high-pressure water into the rubber bag (6), and expanding and extruding the tetrafluoro mixed powder (4) for molding by the rubber bag (6);

7) after the forming is finished, taking down the opening end plate (5) and the closed end plate (8), releasing the clamp (10), putting the steel elbow (3) into the tetrafluoro mixed powder (4) formed by sintering in an oven, setting the temperature at 400 ℃,

8) and after sintering, cooling and shaping, repairing burrs, and inspecting the size of the product to obtain a finished product.

2. The die pressing process of the tetrafluoro bend with the steel lining as claimed in claim 1, which is characterized in that: and (4) mixing the tetrafluoro mixed powder (4), sieving the mixture by a powder sieving machine, and sieving the mixture by a 60-mesh sieve.

3. The die pressing process of the tetrafluoro bend with the steel lining as claimed in claim 1, which is characterized in that: the hoop (10) is provided with a plurality of steel elbows (3), and the positions of the steel elbows (3) contacted with the vibration rack (1) are provided with protection pads.

4. The die pressing process of the tetrafluoro bend with the steel lining as claimed in claim 1, which is characterized in that: after the screw plug (9) is installed, the plug head is flush with the inner sides of the opening end plate (5) and the closed end plate (8).

Technical Field

The invention belongs to the field of chemical equipment, and particularly relates to a die pressing process for a steel lining tetrafluoro bend.

Background

The steel lining tetrafluoro bend is usually lined by a powder mould pressing method, which is an equal-volume, equal-pressure and equal-temperature manufacturing process, and is subject to the process evolution of extruding pipes, winding PTFE belts, adding steel wires in the winding of PTFE, adding steel nets and the like.

The existing molding method of the steel lining tetrafluoro elbow is characterized in that a rubber tube is placed in the steel elbow, tetrafluoro powder is manually filled, an elbow flange is sealed, then the powder is molded through high-pressure water, and then sintering is carried out.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to solve the problems that the existing steel lining tetrafluoro elbow molding method needs skilled workers and manual operation, has low processing efficiency, is easy to shrink holes on tetrafluoro linings, is easy to cause pneumosilicosis for operators and the like.

In order to realize the purpose, the invention provides a steel lining tetrafluoro bend die pressing process, which comprises the following preparation steps:

1) weighing high-density polytetrafluoroethylene powder and silicon dioxide powder, and putting the high-density polytetrafluoroethylene powder and the silicon dioxide powder into a mixer, wherein the polytetrafluoroethylene powder accounts for 92% -96% and the silicon dioxide powder accounts for 4% -8% in percentage by mass; uniformly mixing, stirring at constant temperature of 100-120 ℃ for 15min, and cooling to normal temperature to prepare tetrafluoro mixed powder;

2) placing the part with larger curvature of the steel elbow on a vibration frame, wherein the two flanges are respectively inclined upwards, the vibration frame is provided with a notch matched with the side wall of the steel elbow, and the steel elbow is fixed by a hoop;

3) the rubber bag is arranged in the steel elbow, the rubber bag is in a long tubular shape and is provided with only one opening, the two flanges are respectively locked with the opening end plate and the closed end plate through bolts, the opening part of the rubber bag passes through the round hole of the opening end plate to extend out,

4) the pipeline of the powder feeder is communicated with the feeding pipes on the opening end plate and the closed end plate, and the mixed powder of the tetrafluoro is injected between the rubber bag and the steel elbow; simultaneously starting a vibration motor on a vibration frame, wherein the vibration frequency is 300 times/min, and the vibration amplitude is within 2mm, so that the tetrafluoro mixed powder is fully filled;

5) stopping injecting the tetrafluoro mixed powder when the injected tetrafluoro mixed powder reaches 80% of the specified weight, continuing vibrating for 5 minutes, and then injecting the remaining 20%;

6) after the material injection is finished, stopping vibration, screwing the screw plug into the threads of the feeding pipe, injecting high-pressure water into the rubber bag, and expanding and extruding the tetrafluoro mixed powder for molding by the rubber bag;

7) after the molding is finished, taking down the opening end plate and the closed end plate, releasing the clamp, putting the steel elbow into the tetrafluoro mixed powder formed by sintering in an oven, setting the temperature at 400 ℃,

8) and after sintering, cooling and shaping, repairing burrs, and inspecting the size of the product to obtain a finished product.

Further, the mixed powder of tetrafluoro was sieved with a powder sieving machine and sieved with a 60-mesh sieve.

Furthermore, the hoop is provided with a plurality of steel elbows, and the positions of the steel elbows, which are contacted with the vibration rack, are provided with protection pads.

Furthermore, after the screw plug is installed, the plug head is flush with the inner sides of the opening end plate and the closed end plate.

The invention has the beneficial effects that:

1. according to the steel lining tetrafluoro elbow die pressing process, a proper amount of silicon dioxide is added into polytetrafluoroethylene powder, so that the corrosion resistance, strength and wear resistance of a tetrafluoro lining are improved;

2. according to the invention, the PTFE mixed powder is fully filled between the rubber bag and the steel elbow through the vibrating frame during liner forming, so that the defects of shrinkage cavity and the like are avoided;

3. according to the invention, the tetrafluoro mixed powder is automatically filled, so that the manual participation is reduced, the product quality is improved, and the occupational diseases of operators are avoided;

4. the powder forming link of the invention improves the working efficiency and reduces the finished product time.

Drawings

FIG. 1 is a schematic view of a vibration forming structure of a tetrafluoro-lined steel elbow molding process according to the present invention;

FIG. 2 is a schematic diagram of the steps of the tetrafluoro bend die pressing process of the steel lining.

In the figure: 1. a vibration frame; 2. a vibration motor; 3. a steel elbow; 4. tetrafluoro mixed powder; 5. an open end plate; 6. a rubber bag; 7. a feed pipe; 8. closing the end plate; 9. a screw plug.

Detailed Description

The details of the present invention are described below with reference to the accompanying drawings and specific embodiments.

As shown in fig. 2, the die pressing process of the steel lining tetrafluoro bend comprises the following preparation steps:

1) weighing high-density polytetrafluoroethylene powder and silicon dioxide powder, and putting the high-density polytetrafluoroethylene powder and the silicon dioxide powder into a mixer, wherein the polytetrafluoroethylene powder accounts for 92% -96% and the silicon dioxide powder accounts for 4% -8% in percentage by mass; uniformly mixing, stirring at constant temperature of 100-120 ℃ for 15min, and cooling to normal temperature to prepare tetrafluoro mixed powder 4;

2) as shown in fig. 1, a part with a large curvature of the steel elbow 3 is placed on a vibration frame 1, two flanges 11 are respectively arranged obliquely upwards, a notch matched with the side wall of the steel elbow 3 is arranged on the vibration frame 1, and the steel elbow 3 is fixed by a hoop 10;

3) the rubber bag 6 is arranged inside the steel elbow 3, the rubber bag 6 is in a long tube shape and has only one opening, the two flanges 11 are respectively locked with the opening end plate 5 and the closed end plate 8 through bolts, the opening part of the rubber bag 6 passes through the round hole of the opening end plate 5 to extend out,

4) the pipeline of the powder feeder is communicated with a feeding pipe 7 on the opening end plate 5 and the closed end plate 8, and the tetrafluoro mixed powder 4 is injected between the rubber bag 6 and the steel elbow 3; simultaneously starting a vibration motor 2 on the vibration frame 1, wherein the vibration frequency is 300 times/min, and the vibration amplitude is within 2mm, so that the tetrafluoro mixed powder 4 is fully filled;

5) stopping injecting the tetrafluoro mixed powder 4 when the injected tetrafluoro mixed powder reaches 80% of the specified weight, continuing vibrating for 5 minutes, and then injecting the remaining 20%;

6) after the material injection is finished, stopping vibration, screwing the spiral plug 9 into the thread of the feeding pipe 7, injecting high-pressure water into the rubber bag 6, and expanding and extruding the tetrafluoro mixed powder 4 by the rubber bag 6 to form;

7) after the molding is finished, the opening end plate 5 and the closed end plate 8 are taken down, the hoop 10 is disassembled, the steel elbow 3 is placed into the oven to sinter and mold the tetrafluoro mixed powder 4, the temperature is set to be 400 ℃,

8) and after sintering, cooling and shaping, repairing burrs, and inspecting the size of the product to obtain a finished product.

In practical application, the mixed powder 4 of the tetrafluoro is mixed and sieved by a powder sieving machine and then sieved by a 60-mesh sieve.

In practical application, the hoop 10 has a plurality of steel elbows 3, which are contacted with the vibration rack 1 and are provided with protection pads.

In practical application, after the screw plug 9 is installed, the plug head is flush with the inner sides of the opening end plate 5 and the closed end plate 8.

In summary, the following steps: the invention has stronger corrosion resistance, strength and wear resistance, reduces the manual participation, improves the product quality, avoids the occupational disease of operators, improves the working efficiency and reduces the finished product time.

The basic principles, principal features and advantages of the present invention are described. It should be understood by those skilled in the art that the foregoing embodiments are merely illustrative of the technical spirit and features of the present invention, and the present invention is not limited thereto but may be implemented by those skilled in the art.