GB Stainless Steel Flange Ball Valves

GB Stainless Steel Flange Ball Valves is a rotary shut-off and regulating valve designed and manufactured in strict accordance with Chinese national standards (GB). Made of all-stainless steel with a national standard flanged connection, it can be directly adapted to various industrial piping systems in China.

The valve core consists of a stainless steel valve body/bonnet, stainless steel ball, stem, seat, and optional manual/pneumatic/electric actuators. All components comply with corresponding national standards, ensuring product stability and compatibility.

Its working principle is simple and clear:The stem drives the ball to rotate around a vertical axis.

● At 0°, the ball bore is fully aligned with the pipeline flow path — the valve is fully open, allowing smooth medium flow.

● After rotating 90°, the bore is completely misaligned with the flow path — the valve is fully closed, tightly blocking the medium.

● When rotated between 0° and 90°, it enables precise flow regulation.

It integrates both shut-off and regulation functions, suitable for various industrial working conditions.

Core Product Features

Compliant with GB Standards, Strong Adaptability

Designed and manufactured in accordance with core national standards including GB/T 12237 and GB/T 12224.  Flanged connections meet GB/T 9113, enabling direct connection to mainstream GB flanged pipelines without modification, ensuring easy and efficient installation.

All-Stainless Steel Construction, Excellent Performance

Made of 304/316/316L stainless steel, featuring outstanding corrosion resistance, high temperature resistance, and wear resistance. It can serve corrosive media for a long service life without rusting or damage.

Fast Operation, Precise Regulation

90° rotary on-off design:

● Manual type: on-off time ≤ 30s

● Pneumatic type: ≤ 5s

● Electric type: ≤ 10sWide flow regulation range with a turndown ratio of 100:1 for accurate flow control.

Reliable Sealing, Leakage-Free

Available in soft-sealed (PTFE/EPDM/PPL) and hard-sealed (Stellite alloy hardfacing) versions. The sealing surfaces are precision-machined, and the back-seal stem structure effectively prevents external leakage, ensuring pipeline safety.

Flexible Structure, Wide Compatibility

Supports floating ball and fixed ball structures:

● Floating ball: for medium & low pressure (PN16~PN40), small & medium diameters — simple structure, cost-effective.

● Fixed ball: for high pressure (PN63 and above), large diameters — low operating torque, stable sealing.Manual, pneumatic, and electric actuation are available for different installation scenarios.

Core Specifications

Application Scenarios

With excellent corrosion resistance, high temperature resistance and GB compatibility, GB Stainless Steel Flange Ball Valves are widely used in various domestic industrial fields as a key component for medium shut-off, regulation and diversion.

Typical applications include:

● Petrochemical Industry: Crude oil, refined oil, chemical raw materials, especially sulfur-containing, chlorine-containing corrosive media.

● Municipal Water Supply & Drainage: Tap water, sewage treatment, chlorine-containing water.

● Fine Chemical, Pharmaceutical & Food Processing: 316L version for high-purity, corrosive, hygienic applications.

● Power Industry: Steam, cooling water under high temperature and medium/high pressure.

● Other Fields: Natural gas, LPG, metallurgy, mining and other corrosive pipelines.

Selection Guide

Operation & Maintenance

Installation Notes

● Before installation: Verify model, pressure, material, diameter, seal type and flange face match the pipeline. Check for cracks, rust, and smooth stem rotation.

● Flange installation: Comply with GB 50235 and GB/T 9113. Use matching gaskets. Tighten bolts diagonally and evenly to avoid flange deformation or leakage. Clean sealing surfaces before installation.

Operation Rules

● Open/close: Keep rotation within 0°–90° to avoid damage. Adjust flow slowly.

● Pneumatic/Electric: Commission actuators first to ensure signal synchronization before operation.

Regular Maintenance

● Routine inspection: Check flanges, bonnet and stem seals for leakage; tighten or replace parts as needed.

● Lubrication: Apply stainless steel-compatible grease to stem packing and bearings. Clean internals periodically; replace worn ball/seat.

● Special conditions: Use corrosion-resistant materials for sour service; fire-safe hard-seal valves for flammable areas; low-temperature seals and grease for cryogenic service.

● For long-idle valves: commission no-load, clean debris, and perform a simple seal test before restart.

Design & Manufacturing Standards

GB Stainless Steel Flange Ball Valves are designed, manufactured and inspected in accordance with:

● Valve design: GB/T 12224, GB/T 12237, GB/T 13927

● Structure & flange: GB/T 12221, GB/T 9113

● Material: GB/T 1220, GB/T 13401, GB/T 17491