Fire Hydrant Valve Reducing

3.1 Core Structural Design of Ductile Iron

It adopts an integrated ductile iron structure of "valve body - valve seat - valve stem". The valve body undergoes isothermal quenching, with a Brinell hardness of HB220-250 and a low-temperature impact toughness of ≥12J/cm² at -30℃, completely solving the problem of easy freezing and cracking of traditional cast iron hydrants in frigid regions. The flow channel adopts an optimized Y-type design, and the inner wall is shot-blasted to achieve a roughness of Ra ≤1.6μm. The water flow resistance is reduced by 18% compared with traditional structures, ensuring the rapid formation of an effective water column during a fire.

The valve stem is made of 2Cr13 stainless steel with chrome plating. The diameters are 22mm for DN50 and 25mm for DN65. Equipped with three V-shaped sealing rings, the opening and closing torques are controlled at ≤35N·m and ≤45N·m respectively, allowing even female operators to open and close it easily, meeting the requirements for emergency operation convenience.

3.2 Weather Resistance Enhancement Design

Anti-corrosion Coating: The valve body surface adopts a three-layer protection process of "sandblasting derusting + zinc-aluminum coating + epoxy resin powder", ensuring no rusting after 8000 hours of salt spray corrosion test. It can adapt to corrosive environments such as damp basements and chemical workshops.

Low-temperature Sealing System: The sealing gasket is made of 11mm thickened EPDM with an antifreeze additive formula, maintaining good elasticity even at -30℃. The sealing specific pressure is ≥0.8MPa, complying with the GB/T 13927 Class A zero-leakage standard.

Antifreeze Drainage Structure: A hidden antifreeze drainage hole is set at the bottom of the valve body, which can drain the residual water in the valve cavity after closing, avoiding valve body expansion and cracking caused by low-temperature freezing. The drainage hole adopts a threaded sealing design to maintain airtightness and not affect pressure resistance during normal use.

3.3 Optimization of Russian-Style Adaptation Details

The water outlet adopts a Russian standard K-type internal thread interface with a thread angle of 60°, which perfectly matches the GOST 24215 standard fire hose interface. The sealing reliability after connection is improved by 30% compared with universal interfaces. The handwheel adopts a Russian-style anti-slip rib design with a knurling depth of 1.2mm, ensuring a firm grip even when wearing cold-proof gloves. A Russian standard pressure gauge interface (M20×1.5) is reserved on the side of the valve body, which can be directly connected to locally commonly used pressure monitoring equipment.