Process Units
Process Unit Valve Reference
Valves for the Vacuum Distillation Unit (VDU)
Processes CDU residue under deep vacuum to lift heavier cuts without thermal cracking. The defining valve challenge is sealing at sub-atmospheric pressure while handling viscous, hot residue.
Oil & Gas Refining
What are the critical valves in a Vacuum Distillation Unit?
Vacuum column feed (Gate Valves) — Full-bore isolation for viscous hot residue with minimal flow restriction. Ejector / vacuum system isolation (Butterfly Valves) — Large-bore, low-pressure-drop isolation on the vacuum-generating steam ejector train.
Critical Valve Points
Vacuum column feed
Gate Valves →Full-bore isolation for viscous hot residue with minimal flow restriction.
Ejector / vacuum system isolation
Butterfly Valves →Large-bore, low-pressure-drop isolation on the vacuum-generating steam ejector train.
Unit-Level Valve Strategy
- Vacuum-service valves need positive sealing against inward air leakage, not just process containment - a leaking valve breaks the vacuum and derates the whole unit
- Residue and slop-wax lines run hot and viscous - full-bore, minimum-obstruction valve selection prevents plugging
Equipment in this Unit
Fluids in this Unit
Governing Standards
Related process units
Sealing systems specified in this unit
Reviewed by Process Engineering, Vajra Industrial SolutionsDiscipline: Valve Service SpecificationLast reviewed: 20 June 2026
Connected Engineering
Comparisons
Sourcing valves for a Vacuum Distillation Unit?
Send your unit valve list — we supply the full set (Gate Valves, Butterfly Valves) with certification matched to API 521, in one PO.
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