Stainless steel gate valve is a kind of cut-off type valve made of stainless steel, through the vertical lifting of the gate plate to control the flow of pipeline media or cut off, suitable for water, oil, steam, acids and other media, widely used in petroleum, chemical, electric power and other fields. It is widely used in petroleum, chemical industry, electric power and other fields.
Organisation
The core components of stainless steel gate valve include:
Valve body and bonnet: usually cast in stainless steel (such as 304/316L) or alloy steel, corrosion-resistant and pressure-bearing capacity 26.
Gate: divided into wedge type (single/double gate, resilient gate) and parallel type (single/double gate), to achieve zero leakage through forced sealing or self-sealing Valve stem: tempered and surface treated to achieve zero leakage.
Stem: tempered and surface nitriding treatment, wear-resistant, corrosion-resistant, some large-diameter models are equipped with thrust bearings to reduce the opening and closing torque.
Sealing surface: Surfacing Stellite carbide or PTFE soft seal, high temperature resistance, resistance to particle scouring.
Packing: Polytetrafluoroethylene (PTFE) or graphite material to ensure the reliability of stem sealing.
Main types
According to different classification standards, stainless steel gate valves can be divided into the following types:
Sealing surface configuration:
Wedge gate valve: single gate, double gate, elastic gate (to compensate for processing errors).
Parallel gate valve: single gate, double gate (for high pressure differential conditions).
Connection method:
Flange type: standard flange connection, suitable for large diameter pipelines.
Silk button/silk port type: threaded connection, suitable for small calibre (DN15-DN100) scenarios.
Special features:
Insulated gate valve: integrated thermal insulation jacket to prevent the medium from solidifying or crystallising (applicable temperature -20°C ~ +550°C).
High-pressure heavy-duty gate valve: thickened valve body design, pressure resistance up to PN100 (Class 600), suitable for oil and gas transmission.
Advantages
Strong sealing performance:
Forced sealing: the gate is pressed by external force when closing, the leakage rate is ≤ 10 ppm.
Self-sealing: media pressure to assist the sealing surface fit, reverse pressure still maintain a seal.
Corrosion & High Temperature Resistance:
Stainless steel (304/316L) and hard alloy sealing surface, resistant to acid, alkali, high temperature steam (≤ 550°C).
Low flow resistance & long life:
When fully open, the flow path is smooth, low fluid resistance; stem nitriding treatment and low-friction design, opening and closing life of more than 100,000 times.
Convenient maintenance:
Top-mounted structure (large-diameter models) supports online maintenance without disassembling the valve body.