Valve PartsFull Glossary

Packing (Stem Packing)

Sealing material compressed around the valve stem in the stuffing box to prevent leakage to atmosphere. Common types: PTFE (clean service, to 200 degrees C), graphite (fire-safe, high-temperature, low-emission), and proprietary spiral-wound graphite for ISO 15848 Class A compliance.

Frequently Asked Questions

What is a Packing (Stem Packing) in a valve?

Sealing material compressed around the valve stem in the stuffing box to prevent leakage to atmosphere. Common types: PTFE (clean service, to 200 degrees C), graphite (fire-safe, high-temperature, low-emission), and proprietary spiral-wound graphite for ISO 15848 Class A compliance.

What materials are used for the Packing (Stem Packing)?

Packing (Stem Packing) material selection depends on the process fluid, operating temperature and pressure, and required corrosion resistance. Standard materials include carbon steel (A216 WCB/A105), austenitic stainless steel (SS316/316L), and corrosion-resistant alloys (Hastelloy C-276, Inconel 625, duplex stainless steel 2205/2507) for aggressive service. All materials must be certified with EN 10204 Type 3.1 MTCs traceable to the heat number.

What standards govern the design of the Packing (Stem Packing)?

Valve component design is governed by ASME B16.34 for pressure-temperature ratings, API 600/602 for gate valves, API 609 for butterfly valves, and API 6D for pipeline valves, as applicable. Third-party inspection to these standards ensures compliance. Vajra Industrial Solutions supplies valves with full documentation packages including dimensional inspection records and material certificates.

Technical Support

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Our valve engineers can help specify the right valve for your application. Full project documentation available: MTCs, test reports, dimensional inspection, and third-party inspection coordination.