Globe Valves
Precise throttling and regulation.
Explore Globe ValvesIsolation valve range SIYA supply & sourcing
Gate Valves
Full-flow isolation for pipelines.
Linear-motion isolation valves for full-flow pipeline service where low pressure drop and positive shut-off are important. Cast and forged steel constructions for process, power and oil & gas.
Supplied through selected market sources. Manufacturer and model are confirmed in the quotation; SIYA is not represented as the manufacturer.
Overview
Understanding the gate valve
A gate valve lifts a wedge or gate out of the flow path, leaving an unobstructed bore with very low pressure drop. It is intended for fully open or fully closed duty, not throttling.
Cast steel gate valves cover larger sizes; forged steel compact valves suit smaller sizes and higher pressure. Wedge type, trim and bonnet design are selected from the service.
Construction options
Common gate valves designs
These are general valve-family descriptions, not a statement that every configuration is available. The selected supplier and design are confirmed for each quotation.
| Design | Description | Typical context |
|---|---|---|
| Cast steel, bolted bonnet | Standard refinery / process gate valve | Hydrocarbon, steam, general process |
| Forged steel, compact | Small bore, high pressure; socket-weld, threaded or flanged | Instrument, utility, high-pressure lines |
| Pressure-seal bonnet | Bonnet sealing improves as pressure rises | High-pressure steam, power |
| Wedge: solid / flexible / split | Wedge style chosen for temperature change and seat alignment | Selected per duty |
| Cast iron / ductile iron (water) | Resilient or metal-seated; lower pressure | Water, fire-water |
Technical selection
Specifications confirmed to order
No model-specific size, pressure, temperature, materials, certificates or standards are guaranteed by this page. The exact specification is checked against the selected supplier's datasheet and confirmed in writing before supply.
- Size, pressure & temperature
- Confirm operating conditions and design envelope for the selected model.
- Body, trim & soft parts
- Match the process fluid, temperature and compatibility requirements.
- Ends & installation
- Specify connection type, facing, drilling and applicable piping standard.
- Operation & accessories
- Confirm manual or actuated operation, control signal and accessories.
- Standards & testing
- Confirm the applicable design, inspection and test requirements for the order.
- Documents & traceability
- State certificate and documentation requirements in the enquiry.
Please do not select a valve from a general web description alone. SIYA will confirm the offered make, model, datasheet and deviations with the quotation.
Where they are used
Typical applications
- Oil & gas and refinery pipelines
- Power-plant steam and feedwater
- Chemical and petrochemical plants
- Water and wastewater mains
- Fire-water lines
- General plant isolation
Selection checklist
What to specify
- Fluid, pressure and temperature
- Cast or forged construction
- Wedge type and trim material
- Bolted or pressure-seal bonnet
- End connection and flange facing
- Handwheel, gear or electric actuator
Need a valve for a specific duty?
Send the details you have. We’ll help confirm the right specification.
Include service conditions, quantity and delivery location. A datasheet, BOQ or valve photo is also helpful.