The valve packing is installed in the packing room of the upper bonnet to prevent leakage due to stem movement. The packing materials are mainly PTFE, Graphite and etc. PTFE packing is characterized by strong lubrication performance, but it is used only at temperatures below 200℃ and cannot be used for molten alkali metals and high-temperature fluorine and hydrogen fluoride media. Graphite filler is generally ring-shaped and offers excellent high temperature resistance up to 600 ℃.
Flexible graphite packing ring or graphite gaskets is pressed with pure expanded graphite tape mounted on the seats with stainless steel wire mesh and then through lubricant, graphite powder and corrosion inhibitor surface treatment to the specific density required by valve applications. Graphite packing ring supplies good resilience, chemical stability and can provide effective sealing. It can also be used in combination with other end rings to provide stability and reliability even under harsh conditions, suitable for hot water, high-pressure steam, heat exchange liquid, ammonia gas, hydrogen, organic solvent, hydrocarbon, low-temperature liquid, but due to the greater friction, the graphite packing ring cannot be used for strong oxidant such as concentrated sulfuric acid concentrated nitric acid medium.
Inner diameter: Ф 6 – Ф 560 mm
Outer diameter: Ф 12 – Ф 610 mm
Thickness: 3 mm-28mm
Chemical tolerance: PH 0-14
Working temperature: -100-+800 ℃
Working pressure: 35 MPa
As a professional industrial valve manufacturer and supplier, we also provide valve seats and components like fire-safe graphite rings with a metal sheet (304, 316, 316L, Inconel, etc.) with various dimensions even according to the technical drawings. Learn more, contact us now!