Density increase of PTFE sintered parts after water or oil immersion

Density of sintered PTFE seals increases after long-term immersion in liquid media. Density differences are evident between different parts of the product, affecting the overall performance consistency of the product.

(1) Process factor: The incompletely sintered open-cell structure is penetrated and filled by liquid under hydraulic pressure, This factor affects the '2079851475616104453 and final quality of the product. (2) Process aspect: Uneven pressure transmission or insufficient holding pressure causes densification differences among parts. (3) Material aspect: Filler sedimentation or composition segregation causes local density abnormalities. (4) Operation aspect: Uneven feeding or improper filling sequence.

(1) Formulation adjustment: Increase the sintering degree to reduce open porosity, Adjust gradually and verify the effect, ensuring that other performance indicators of the product are not affected. (2) Implementation measure: Perform a liquid penetration test on the product after sintering, Develop a specific operation plan based on actual production conditions, and verify the implementation effect. (3) Material selection: Select a sintering process with a high closed-cell rate., Establish material selection evaluation criteria, and determine the optimal solution through comparative tests. (4) Preventive measure: Establish a raw material batch inspection system, regularly sample product density and mechanical properties, and establish quality trend analysis.

The essence of uneven density is inconsistent distribution or densification of the material during the '2079851475616104453; it is necessary to optimize the feeding method and pressure transmission.