utilitySub-atmospheric pressure
Valves for Vacuum Service Service
Vacuum service encompasses any application where the process pressure is below atmospheric (0.1–101 kPa absolute). Common vacuum applications include distillation columns (crude vacuum unit), ejector/vacuum pump suction, pharmaceutical lyophilisation (freeze-drying), semiconductor process chambers, paper machine forming sections, and industrial furnaces. The key valve challenge is that the pressure differential acts in the reverse direction - atmospheric pressure acts to collapse thin-wall structures and to pull stem packing inward rather than push it outward, requiring different seat and packing design considerations.
Pressure Range
0.001–101 kPa absolute (deep vacuum to near-atmospheric)
Temperature
Ambient (pharma freeze-drying) to 420°C (refinery crude vacuum unit)
Industries
Refinery crude vacuum unit, Pharmaceutical (lyophilisation), Chemical distillation
What valves are used for Vacuum Service service?
Gate Valve (OS&Y, pressure-seal bonnet for high-temp vacuum) are recommended for Vacuum Service service: Mainline isolation on crude vacuum column overhead and bottoms.
Key Properties - Vacuum Service
- Pressure below atmospheric - 1 mbar to 100 kPa absolute
- External (atmospheric) pressure greater than internal - reverse pressure loading on seats
- Packing leakage draws air in (rather than fluid out) - atmospheric oxygen ingress hazard in hydrocarbon vacuum service
- Crude vacuum unit: 5–40 mmHgA at 350–420°C - high temperature + deep vacuum
- Pharmaceutical lyophilisation: 0.1–1 mbar absolute
Vajra Industrial Solutions manufactures and supplies valves for Vacuum Service service — including gate valve (os&y, pressure-seal bonnet for high-temp vacuum) — in corrosion-appropriate materials selected for the operating conditions described here, with full material and test documentation.
Need valves for Vacuum Service service?
Send your fluid conditions — we'll recommend the right valve, material and standard, with a 24-hour quote.
Material Compatibility - Vacuum Service
Ratings are indicative. Actual compatibility depends on concentration, temperature, velocity, and presence of contaminants. Always consult corrosion tables or a materials engineer.
| Material | Rating | Notes |
|---|---|---|
| Carbon Steel (WCB) | Excellent | Standard for high-temperature refinery vacuum service. |
| A217 WC6/WC9 (Cr-Mo) | Excellent | For crude vacuum unit above 400°C. |
| SS 316L | Excellent | For pharmaceutical and clean vacuum service. |
| Graphite packing | Excellent | Preferred packing for vacuum valves - maintains seal under reverse differential pressure. |
Recommended Valves
Gate Valve (OS&Y, pressure-seal bonnet for high-temp vacuum)
Mainline isolation on crude vacuum column overhead and bottoms
Full selection guideButterfly Valve (large-bore, high-performance)
Low-pressure vacuum duct isolation in ejector systems and paper machine
Full selection guideBall Valve (SS 316L, PTFE seat)
Pharmaceutical vacuum service - tight shutoff required, zero external leakage
Full selection guideSafety Vacuum Relief Valve (vacuum breaker)
Prevention of vessel collapse on loss of vacuum - admits air to break vacuum safely
Full selection guideValves to Avoid
Wafer-pattern valves without bolted support in full vacuum - face gaskets may be pulled inward
Butterfly valves with rubber liners for deep vacuum - liner collapses
Special Considerations
Applicable Standards
Shop Valves for Vacuum Service Service
Other Fluid Services
Vacuum Service Service — Procurement & Specification
Typical Applications
Available Standards
Material Options
Documentation Available
- -EN 10204 3.1 Material Test Certificates (heat traceable)
- -API 598 hydrostatic shell & seat test reports
- -Dimensional inspection reports
- -Full Manufacturing Data Record (MDR) / data book on request
Inspection Options
- -In-house QC inspection on every order
- -Third-party inspection (SGS / Bureau Veritas / TÜV / DNV) coordination
- -Witness and hold points accommodated on request
Order Quantities
Flexible — from single critical-spare valves to full project lots.
Export
Worldwide export with complete documentation (COO, EUR.1, packing lists) to 20+ countries.
Custom Engineering
Built to your specification — materials, trim, pressure class and special service (NACE, fire-safe, IBR, cryogenic).
Delivery Support
Dispatch from Vadodara, Gujarat with documented lead times and priority handling for urgent requirements.
Engineering references
Connected Engineering
Need Valves for Vacuum Service Service?
Tell us your fluid, pressure, and temperature — we'll recommend the right valve, material, and standard, with a 24-hour quote.