Teflon

1. Chemical Industry Linings for tanks, vessels, and pipes to resist corrosive chemicals Valves, pump components, and gaskets exposed to acids, bases, or solvents Seals and diaphragms in chemical processing equipment 2. Mechanical & Engineering Applications Bearings, washers, slide plates, and gears requiring low friction Machine parts operating under high wear or corrosive conditions Sealing components in pumps, valves, and compressors 3. Electrical & Electronics Insulators, cable sheathing, and wiring components High-performance dielectric materials for capacitors and electronic devices 4. Food Processing & Pharmaceutical Non-stick surfaces in cookware, molds, and conveyor belts Equipment parts resistant to cleaning chemicals and high temperatures 5. Aerospace & Automotive Seals, gaskets, and protective coatings exposed to extreme temperatures Components requiring chemical resistance and low friction 6. Miscellaneous Filtration membranes, tubing, and hoses for harsh chemical or thermal environments Coatings for industrial equipment to reduce friction and wear

Teflon (PTFE) is a soft, low-friction polymer, and its hardness is significantly lower than most engineering plastics or metals. It is naturally flexible and deformable, which contributes to its excellent sealing and non-stick properties, but limits its load-bearing capacity. Unfilled PTFE typically has a Shore D hardness of 50–60, making it relatively soft and compressible. Filled PTFE (with glass, carbon, or bronze) achieves higher hardness values (Shore D 65–80), providing improved wear resistance, dimensional stability, and load-bearing capability. Hardness is slightly affected by temperature, but PTFE retains its soft, compliant nature across its operating range of -200°C to 260°C. Because of its low hardness, PTFE is not suitable for high-load structural applications without reinforcement.

1. Annealing / Stress Relieving: PTFE parts are often annealed by heating to 260–300°C for 1–3 hours depending on thickness, then slowly cooled. This process reduces internal stresses from molding or extrusion, preventing warping, shrinkage, and cracking during service. Annealing improves dimensional stability and creep resistance in high-temperature applications. 2. Molded or Machined Parts: Newly machined PTFE components may experience slight shrinkage; post-machining annealing ensures precise dimensions. Thick sections or reinforced PTFE grades may require longer annealing times to relieve internal stresses evenly. 3. Important Notes: PTFE has excellent thermal stability up to 260°C, so heat treatment does not degrade chemical properties. Overheating above 350°C can lead to oxidation and discoloration. Annealing is particularly important for precision components, seals, bearings, and low-friction parts.

Unfilled PTFE: Naturally soft and flexible, with a Shore D hardness of 50–60. It cannot be hardened by heat treatment. Reinforced PTFE: Incorporating glass, carbon, or bronze fillers increases hardness (Shore D 65–80), improves wear resistance, load-bearing capacity, and dimensional stability, but still does not achieve metal-like hardening. Annealing / Stress Relief: Controlled thermal annealing slightly improves surface hardness and stability by relieving internal stresses from molding or machining. Surface Treatments: Specialty coatings or composites can provide localized hardness or improved friction properties, but the bulk material remains inherently soft.

1. Thermal Welding Methods Hot Gas Welding: Heated PTFE surfaces or filler rods are fused together using hot air or inert gas. Compression / Heat Welding: PTFE sheets or parts are pressed together under controlled heat to form a joint. Laser or RF Welding (Special Grades): Occasionally used for precision or industrial applications with thin films. 2. Adhesive Bonding Specialized PTFE adhesives or primers can bond PTFE to itself or to other materials. Surface preparation, such as etching or chemical treatment, improves adhesion. 3. Important Considerations Surface Preparation: PTFE has a very low surface energy, making bonding difficult without proper pre-treatment. Temperature Control: Excessive heat can degrade the polymer, while insufficient heat results in weak joints. Reinforced PTFE: Filled grades may require modified techniques due to different thermal conductivity and melt behavior.

1. Machining Characteristics: Easy to Cut: Can be drilled, milled, turned, or sawed with standard tools for plastics or soft metals. Chip Formation: Produces long, stringy chips; proper chip evacuation and sharp cutting tools are recommended. Surface Finish: Smooth finishes are achievable with sharp tools, low feed rates, and slow cutting speeds. Thermal Sensitivity: PTFE can melt or deform if cutting generates excessive heat. 2. Factors Affecting Machinability: Reinforcement: Glass- or carbon-filled PTFE is more abrasive and requires harder tools (HSS or carbide) and slower feed rates. Thermal Expansion: PTFE’s high coefficient of thermal expansion requires careful fixturing to maintain dimensional accuracy. Tool Selection: Use sharp, non-stick coated, or carbide-tipped tools to reduce friction and heat buildup. 3. Practical Tips: Allow for post-machining annealing to relieve stress and stabilize dimensions. Avoid excessive speed or pressure to prevent surface melting or burr formation. Proper clamping and cooling help achieve precise tolerances and smooth finishes.

We are a reputed supplier of high-quality Teflon (PTFE), offering unfilled, glass-filled, carbon-filled, and bronze-filled grades from trusted domestic and international manufacturers. Our inventory includes rods, sheets, tubes, films, and custom-machined components, ensuring suitability for industrial, chemical, electrical, and food-processing applications.