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Characteristics of PTFE products

1. Corrosion resistance

PTFE products have excellent corrosion resistance, can withstand the corrosion of various acid and alkali media, can work in various corrosive media for a long time, is not corroded, and has good corrosion resistance.

2. Heat resistance

PTFE products have excellent heat resistance, can work in the temperature range of -180 ° C ~ +260 ° C for a long time, strong heat resistance, can resist high temperature corrosion.

3. Low friction coefficient

PTFE products have a low coefficient of friction, the coefficient of friction is only 0.04, much lower than other plastics, can effectively reduce the friction loss of mechanical equipment, improve the service life of mechanical equipment.

4. Low adhesion

PTFE products have low adhesion, which can effectively prevent adhesion between objects, effectively reduce the friction loss of mechanical equipment, and improve the service life of mechanical equipment.

5. Low temperature ductility

PTFE products have low temperature ductility and can maintain their elasticity at a temperature of -180 ° C, which can effectively prevent the damage of mechanical equipment in a low temperature environment.

6. Chemical corrosion resistance

PTFE products have excellent chemical resistance, can withstand the corrosion of various acid and alkali media, can work in various corrosive media for a long time, is not corroded, and has good chemical resistance.

7. Oil resistance

PTFE products have excellent oil resistance, can withstand the corrosion of various oils, can work in various oil media for a long time, is not corroded, and has good oil resistance.

8. Water resistance

PTFE products have excellent water resistance, can withstand the corrosion of various water media, can work in various water media for a long time, is not corroded, and has good water resistance.

PTFE product processing technology

1, extrusion molding

After the PTFE particles are heated and melted, they are extruded through an extruder into a product of the desired shape. This method is suitable for making pipes, plates, bars, etc.

2, compression molding

After the PTFE particles are heated and melted, they are compressed and formed by a mold. This method is suitable for making thin-walled pipes, pipe fittings, valves, etc.

3, injection molding

After the PTFE particles are heated and melted, they are injected into the mold by an injection molding machine to make the desired shape of the product. This method is suitable for making a variety of small parts, precision accessories and so on.

4, coating processing

After mixing PTFE with other materials (such as carbon fiber, metal, etc.), it is coated on the surface of the substrate by coating, spraying and other methods to improve the performance and wear resistance of the material.

5, stretch processing

After heating PTFE to a plastic temperature, it is stretched through a stretching machine to increase its strength and stiffness. This method is suitable for making high-strength parts, springs, etc.

Pay attention to PTFE products when processing

1, PTFE products processing, should pay attention to the use of mechanical equipment, requiring the tool sharpening very sharp.

Can not use carbide cutting tools, after all, carbide cutting tools, can not sharpen the blade is very sharp, if forced to use, it will affect the dimensional accuracy and surface quality of PTFE products.

2, PTFE products processing, can not add coolant.

Because the PTFE turning board is molded with PTFE resin, and then converted into products after sintering, and the PTFE molded board is formed at room temperature, and then cooled by sintering, if the coolant is added in the processing of PTFE products, it is easy to affect the quality of PTFE products, if it is used in the use of occasions, It doesn't take long for the pipes to leak.

3, PTFE products processing, should pay attention to the speed of the machine.

If the speed is too high, it is easy to cause the material to be attached to the inside of the cylinder wall, so when the polytetrafluoroethylene products are processed, the speed of the mixture should be moderate, the mixing is uniform as the standard, and in order to make the extrusion agent more fully dispersed to the surface of the powder particles, the mixture must be sealed at room temperature (23 ° C or slightly higher) for 5 to 15 hours.

4, PTFE products processing, should pay attention to the determination of the benchmark.

Correct selection of parts in the processing of the positioning benchmark, to meet the specific requirements of reliable positioning and high precision, easy positioning, easy processing, easy clamping and simple fixture structure, in order to ensure the processing margin of parts. When parts have different machined surfaces, these unmachined surfaces should be used as rough benchmarks; If the part has several unmachined surfaces, the unmachined surface with higher relative position accuracy to the machined surface requirements should be used as the rough reference; And as a coarse reference surface should be flat, no flash, burrs or other surface defects.

Problems that occur easily when PTFE products are processed

1, PTFE products deformation

PTFE products creep resistance is poor, the mechanical and bearing capacity is poor, the linear expansion coefficient is large, the thermal conductivity is poor, when the traction speed is not smooth/machine heating temperature shaking/screw movement speed is not smooth/porous plate filter blocking situation, PTFE products are prone to deformation, especially reflected in the diameter of PTFE special-shaped parts change greatly.

2, PTFE products appearance problems

① The appearance of PTFE products is rough and dull. This is because when PTFE products are processed, the heating temperature of the material is low and the plasticization of the material is uneven; The uneven plasticization of the material is caused by more impurities when the filter is used.

② There are bubbles or silver wires on the surface of PTFE products, which may be because there are problems with the material treatment during the processing and production of PTFE products, such as the high water content of the material and the high temperature of the heating machine heating cylinder.

The roundness of PTFE products is not uniform, possibly because of fluctuations in the temperature of the molding die. When the melting temperature of PTFE products extrusion molding is unstable, the equipment screw wear is serious, resulting in confusion of extrusion melting pressure of PTFE special-shaped parts, which leads to uneven roundness of PTFE products.

3, PTFE products extrusion cut

PTFE products feed hopper entrance has a single screw extruder, the higher the temperature of the feed section, the better, the lower the temperature of PTFE products molding mold, the greater the resistance of molten material operation, but in the actual processing of PTFE special-shaped parts, more impurities in the equipment filter screen, the filter screen is blocked, resulting in PTFE products extrusion out of material situation.