Assembly Process
01Valve Assembly OverviewComplete F91 parallel double-disc gate valve positioned in the workshop.
02Valve Body ProtectionLarge valve body section protected during workshop handling.
03Upper Structure AssemblyYoke and upper assembly components prepared for installation.
04Machined Internal ComponentFinished cylindrical internal component after machining.
05Dimensional InspectionMachined surface dimensions checked during production.
06Disc Component InspectionParallel disc components checked before assembly.
07Machined Crosshead ComponentCrosshead component prepared for the parallel double-disc assembly.
Assembly and Inspection Scope
This production update documents the assembly and inspection of an 8-inch Class 900 A182 F91 parallel double-disc gate valve for high-temperature steam service in a power plant. The design basis is NB/T 47044 and the specified test standard is API 598. Final configuration and acceptance criteria are governed by the approved drawing, purchase specification and inspection plan; photographs alone do not establish the valve’s complete pressure-temperature or sealing capability.
Items confirmed during assembly
- Identification of A182 F91 parts and components against production traveller and material records.
- Parallel discs, seats and stem alignment, operating movement and accessible sealing surfaces.
- Accessible dimensions against the approved drawing and production documents.
- Packing, bolting, operating components, marking and preservation as specified.
Documents to request before shipment
Depending on the purchase order, the final document package may include material certificates, dimensional records, applicable NDE reports, API 598 test records, assembly records, nameplate details, preservation records and final packing photographs.
Project release basis
Project release should reference the approved drawing, bill of materials, inspection and test plan, NB/T 47044 design basis, API 598 test procedure and traceability records. Dimensions, end connections, trim, seat leakage, NDE extent and shipping preservation remain order-specific until confirmed in the purchase order and approved manufacturing documents.
Need a power plant gate valve quotation?
Send the datasheet, steam service conditions and required inspection scope for a project-specific technical review.