What is a Diaphragm Valve? What Makes PFA Diaphragm Valves Unique?​

​The operation of a diaphragm valve is ingenious. When you turn the handwheel clockwise, the valve stem moves downward, compressing the diaphragm. This causes elastic deformation, pressing the diaphragm tightly against the weir (in weir-type valves) or the bottom of the straight-through flow path (in straight-through types), completely shutting off the flow path and achieving closure. Conversely, turning the handwheel counterclockwise raises the stem, allowing the diaphragm to elastically return to its original shape, unblocking the flow path, and opening the valve.

What is a check valve? PTFE Check Valve

A check valve is a valve that only allows the medium (liquid or gas) to flow in one direction and prevents backflow. Its core function is to enable unidirectional flow through internal structures (e.g., valve core, spring), and it is widely used in fluid conveying systems to prevent damage, process abnormalities, or energy loss caused by reverse flow (e.g., check valves at pump outlets).

From Resin to Finished Product: 5 Key Process Controls in PTFE Tube Extrusion

Polytetrafluoroethylene (PTFE) tubes, renowned for their "king of plastics" properties of exceptional temperature and corrosion resistance, are widely used in chemical processing, medical devices, semiconductors, and other high-stakes industries. Despite their deceptively simple appearance, producing a smooth, uniform, defect-free PTFE tube from raw resin involves a sophisticated sequence: resin compression molding → sintering → extrusion → cooling. Each step’s process parameters directly dictate the final product’s performance and yield. This article breaks down the critical controls in these core processes, revealing how precise engineering resolves common issues like rough inner walls, uneven wall thickness, and cracking.

The Impact of Wall Thickness on the Mechanical and Chemical Properties of PFA Tubes

Pressure Resistance: Generally speaking, the thicker the wall of a PFA tube, the stronger its pressure resistance. A thicker wall can withstand higher internal pressures without cracking or deforming. For example, in high-pressure fluid delivery systems—such as the transportation of high-pressure chemical reagents in chemical production—thick-walled PFA tubes are required to ensure the safe operation of the system. In contrast, thin-walled PFA tubes have relatively lower pressure-bearing capacity and are suitable for low-pressure environments.

Common Failures and Causes of Diaphragm Pumps

Failure: Failure to discharge liquid or insufficient dischargeCauses:① Blockage in the suction pipe or the suction line valve not being opened.② Excessive length of the suction pipeline with too many sharp bends.③ Leakage in the suction pipeline.