• August 12. 2022

1. Tensile property of valve stem sealing material Tensile property is the first property to be considered for sealing materials, including tensile strength, constant tensile stress, elongation at break and permanent deformation at break. The tensile strength is the maximum stress at which the specimen is stretched to fracture. The constant elongation stress (constant elongation modulus) is the st...

• February 26. 2024

JST designs and manufactures spring energized lip seals for ball valve. In this article, we will introduce some lip seals used for different sealing application in ball valve.     Lip seal type FVR is used for ball valve seat sealing. As shown in picture Fig-1, the FVR lip seal contains four parts. 1- T ring (material: carbon filled PTFE), 2- U ring (material: carbon filled PTFE), 3-Spri...

• August 28. 2026

Polypak seals are critical dynamic sealing components in gate valves, particularly in oil and gas applications where reliable shut-off is essential. When leakage occurs, a systematic troubleshooting approach can help identify the root cause and determine the most effective remedy. This guide outlines the key steps and considerations for diagnosing Polypak seal leakage in gate valves.   Step 1...