Materials of Construction (MOC)
| Component | Material Specification |
|---|---|
| Body & Bonnet | Stainless Steel (ASTM A351 Gr. CF8/CF8M) |
| Stem / Spindle | SS 304 / SS 316 |
| Seat / Trim | PTFE / RPTFE / Integral |
Technical Specifications
| Parameter | Specification / Standard |
|---|---|
| Manufacturing / Design Standard | ASME B16.34 / API 603 / API 6D |
| Testing Standard | API 598 / EN 12266-1 |
| Pressure Rating | Class 150 to Class 600 / PN16 / PN40 |
Features & Benefits
Multi-Ply Bellows Stem Seal
Hydroformed multi-ply SS316L bellows provides an absolute dynamic seal around the stem, eliminating all packing leakage and meeting the most stringent VOC emission regulations (TA-Luft, ISO 15848-1).
Secondary Graphite Packing
Graphite braided packing located below the bellows acts as a secondary static seal in the unlikely event of bellows failure, providing fail-safe emission control.
Bellows Anti-Torsion Device
Stem guide and anti-torsion pin prevent bellows rotation during valve operation, eliminating torsional stress that causes premature bellows failure.
Visual Bellows Failure Indicator
A tell-tale hole or leakage port between the bellows and secondary packing provides immediate visual indication of bellows integrity during routine inspection.
Zero External Emissions
Bellows seal eliminates all fugitive emissions from the stem seal, meeting TA-Luft, ISO 15848-1, and EPA Method 21 requirements for VOC-regulated applications.
Soft or Metal Seat Options
PTFE/RPTFE soft seat option provides bubble-tight Class A shutoff for clean service; Stellite metal seat provides high-temperature and abrasion resistance for severe service.