PFA processing molding method

1, molding

When the melting finger of PFA product is relatively high molecular weight, it is not easy to flow, and the viscosity is large, it is usually suitable for processing by die-forming method. If this method is used for processing, it needs to be maintained for a certain time, and after slow cooling under pressure, it can be demoulded.

2, extrusion molding

Among the processing and molding methods of PFA machine, extrusion molding is a common single product solute, which can be processed by extrusion molding when it is greater than a certain value, and this method can produce film and cable insulation layer pipes. And because the melt viscosity of PFA products is relatively high, it has a relatively high tensile ratio when extrusion molding, and can quickly obtain smooth extrudates.

3, injection molding

Injection molding is also a PFA product can choose a molding processing method, this method needs to stay in a certain range, and needs to produce a variety of complex shapes of electronic appliances, aerospace industry aviation, medical testing equipment, chemical testing equipment and industrial parts and so on.

Our Guangzhou OTEM Engineering Plastics Co., Ltd. has more than 20 years of PFA, PTFE, PVDF and other fluorine plastics processing operations, we have more than 2,000 square meters of physical processing plants, as well as professional production equipment and professional production design team, can bring you quality products and services!

Manufacturing process of PFA pipe

1. Prepare raw materials

First you need to prepare the PFA raw material, which is usually provided in granular form. In the manufacturing process, PFA raw materials with certain fluidity and processing properties should be selected to facilitate molding and processing.

Step 2 Squeeze out

The PFA raw material is heated above the melting point, and the molten PFA raw material is extruded by an extruder. This process is similar to the production of plastic pipes, but PFA pipes require higher processing temperatures and pressures. Extruders typically have multiple heating zones and multiple extrusion outlets and can produce PFA tubing of various specifications and sizes.

Step 3: Cool

The extruded PFA pipe will gradually cure after cooling, and at this time, the pipe needs to be cooled to avoid deformation or shorten the life of the pipe.

Step 4 Cut

The cured PFA tube is cut to the desired length, usually using a cutter or saw.

5. Check and pack

Inspection and packaging of PFA pipe after cutting. Inspection mainly includes appearance, size, mechanical properties, etc., to ensure that the pipe meets the quality standards. Packaging materials such as plastic bags or cartons are generally used to protect the pipes from damage.

PFA requirements for injection molding machines

1. High melting temperature

The melting temperature of PFA is much higher than that of ordinary plastics, usually above 300¡ãC. Therefore, it is required that the heating system of the injection molding machine can quickly and stably heat the raw materials in the barrel to a molten state.

2. High stress

The molecular chain of PFA is longer and the intermolecular force is larger, so higher injection pressure is required to fill the mold cavity. In general, the injection pressure of PFA is higher than that of ordinary plastics.

3. High precision requirements

The molecular chain structure of PFA is special, and it is easy to be deformed or cracked by external factors. Therefore, the accuracy of the injection molding machine is required to be higher, including the manufacturing accuracy of the mold, the stability of the injection system and the response speed of the control system.

4. High wear resistance requirements

The friction coefficient of PFA is small, and it is easy to produce wear and thermal damage during high-speed injection and high-pressure injection. Therefore, parts such as the screw, cylinder and seal of the injection molding machine are required to have high wear resistance and corrosion resistance.

5. High control system requirements

The PFA process is complex and requires precise temperature, pressure and flow control. Therefore, the control system of injection molding machine is required to have high precision, high stability and high reliability, and can meet the requirements of complex processing technology.

PFA processing precautions

1. Crystalline material, small moisture absorption. It can be processed into products by the usual thermoplastic processing methods.

2. Poor fluidity, easy to decompose, decomposition of corrosive gas. It should be strictly controlled that the molding temperature should not exceed 475 degrees, the mold should be heated to 150-200 degrees, and the gating system should have little resistance to the material flow.

3. Translucent granules, injection molding, extrusion molding. Molding temperature 350-400 degrees, 475 degrees above easy to cause discoloration or bubbles. And note that demoulding can be difficult.

4. Specific gravity: 2.13-2.167g/cm ? molding shrinkage :3.1-7.7%

5, because the molten material has a corrosive effect on the metal, long-term production, the mold needs chrome plating treatment.