Gauge Root Valve -- Piston Type SS316
Rising Stem Piston Gauge Isolation Valve with Low Pressure Drop
Document No.SV-DS-INS-002
RevisionRev A
DateMay 2026
ManufacturerSupreme Valves India, Ahmedabad, Gujarat, India
This datasheet covers gauge root piston valves in SS316 with rising stem and smooth bore for primary isolation of pressure gauges, dial gauges, and recorders in process plants.
Technical Specifications
| Parameter | Specification |
|---|
| Size Range | 1/2" to 1" NPT process x 1/2" NPT gauge connection |
| Pressure Rating | PN100 / Class 600 / 1,500 PSI |
| Body Material | SS316 forged barstock or investment cast CF8M |
| Valve Type | Rising stem piston plug valve |
| Plug Material | SS316 polished piston with ground seat |
| Seat Material | Integral SS316, matched-lapped to piston |
| Temperature Range | -29°C to +425°C (graphite packing) |
| Connections | NPT male/female process; 1/2" NPT female gauge |
| Bonnet | Union bonnet for in-line packing and plug replacement |
| Operation | Rising stem handwheel with position indicator |
| Features | Smooth bore low DP, rising stem, blow-out proof, union bonnet, gauge snubber option |
Materials of Construction
| Component | Material |
|---|
| Body | SS316 forged barstock or investment cast CF8M, machined cylinder bore and seat |
| Bonnet | SS316 union bonnet with smooth ACME threads and gasket groove |
| Piston | SS316 polished piston with ground cylindrical section and matched-lapped seat face |
| Seat | Integral SS316, precision lapped to piston for bubble-tight shutoff |
| Stem | SS316 rising stem with ACME threads, thrust bearing, and position indicator collar |
| Packing | Graphite braided rings with anti-extrusion end rings for high temperature |
| Gasket | Spiral-wound SS316 + graphite for body/bonnet joint |
| Handwheel | Cast iron or SS304 spoke handwheel, chrome-plated |
Testing & Inspection
| Test | Requirement |
|---|
| Test Standard | API 598 / ISO 5208 |
| Certification | CE, ISO 9001 |
Applicable Standards
| Standard | Description |
|---|
| Design Standard | ASME B16.34 / BS 1873 (adapted) |
Notes
- Gauge root valve must be rated for full process design pressure; undersizing or down-rating can result in gauge failure and personnel hazard.
- Rising stem provides visual position indication; do not rely on handwheel position alone as back-seating may allow partial flow.
- Gauge snubber orifice is factory-sized for typical gauge element volume; specify gauge manufacturer and model for custom orifice sizing.
- For viscous or polymerising media, specify extended bonnet or steam jacket to prevent solidification in body cavity.
- Union bonnet threads must be lubricated with anti-seize compound during assembly to prevent galling in SS316-to-SS316 contact.
