Pneumatic high-pressure shut-off valve J641H-25C

Product Features

High pressure cutoff, pneumatic control, interlocking opening and closing

Model number

J641H-25C

Specification and caliber

DN15-DN300

Pressure level

PN25

Material

WCB

Product Introduction

J641H-25C Pneumatic High Pressure Stop Valve

Pneumatic high-pressure shut-off valve J641H-25C is used for automatic switching or process control in boiler auxiliary equipment, thermal pipelines, energy devices, and industrial pipelines. The selection should check the medium, temperature, maximum and normal flow rates, pressure difference before and after the valve, pipeline standards and control requirements, and should not be based solely on the existing pipe diameter. This article lists the commonly used configuration range, and the final data should be based on project conditions, order confirmation forms, and manufacturing drawings.

Structure and Drive

J641H-25C adopts a straight through cut-off type, flange connection, and upper sealing structure. When the fluid passes through the valve body channel, the pneumatic actuator is paired with a switching mechanism to change the position of the opening and closing parts, completing the cutting or adjustment. The actuator should match the torque or thrust of the valve and reserve a reasonable safety factor. When feedback, positioning, or interlocking is required, the control signal, power or gas source, protection level, and fault safety location should be clearly defined during the ordering phase to avoid on-site interface mismatch.

Material and sealing

The commonly used caliber is DN15-DN300, the pressure rating is PN25, and the valve body material can be selected as WCB. The selection of materials should take into account the corrosiveness of the medium, chloride ions, temperature fluctuations, and cleaning conditions. The allowable temperature, pressure difference, and leakage level of metal seals should be checked simultaneously. For steam, particle containing, easily crystallized or frequently operated conditions, the hardness of valve internals, packing form and erosion prevention measures should also be confirmed.

Product Specifications

Product Model	J641H-25C
Structural form	Straight through cut-off type, flange connection, upper sealing structure
Nominal Diameter	DN15-DN300
pressure rating	PN25
Valve body material	WCB
sealing form	metal seal
Drive Type	Pneumatic actuator with conversion mechanism
Applicable temperature	-20℃ to 425℃, confirm according to the packing and valve seat
Applicable Medium	Steam, hot water, oil products, and general industrial gases

Applicable working conditions

The product features include high-pressure cut-off, pneumatic control, interlocking opening and closing. After reasonable configuration, it can be used for boiler auxiliary equipment, thermal pipeline network, energy equipment, and industrial pipeline network. Dangerous areas should select corresponding actuators, accessories, and wiring methods according to explosion-proof zones; Food, pharmaceutical and other systems also need to confirm the requirements for liquid receiving materials, surface treatment and cleaning. Projects involving oxygen, highly corrosive or toxic media should undergo specialized material and safety reviews.

Installation and Debugging

Before installation, the nameplate, flow direction, and connection standards should be checked, and welding slag and hard debris should be removed to ensure the concentricity of the front and rear pipe sections and avoid the transmission of pipeline stress to the valve body. Maintain maintenance space around the actuator, and prevent rainwater from entering the cable entrance; Pneumatic accessories should use a clean and dry air source. The first debugging should check the switch position, stroke feedback, interlocking logic, and sealing condition under low-risk conditions, and then gradually enter the working pressure.

Operation and maintenance

Observe action time, abnormal noise, leakage, valve position feedback, and control signals during operation. When the action is slow, first check the power or gas source, wiring, filter pressure reducing valve, and actuator, and then check the valve stem, valve seat, and seals. It is not advisable to blindly increase the driving force. Before maintenance, it is necessary to isolate the medium, relieve pressure, and confirm that there is no residual energy. After replacing the seal, conduct strength, sealing, and action tests according to regulations, and record the material of the spare parts and the date of maintenance.

Q&A on Selection of Pneumatic High Pressure Stop Valve

Can J641H-25C switch directly under large pressure differences?

The valve internals, valve stem, and actuator output force should be checked against the maximum closing pressure difference, and the actual flow direction should be confirmed. The nominal pressure of the valve body cannot be directly used as the allowable opening and closing pressure difference, and the problem of loose closure cannot be solved by blindly increasing the driving force.

Can the old globe valve be directly replaced with J641H-25C with the same diameter?

It is also necessary to verify the flange standards, sealing surfaces, structural length, flow direction, and allowable pressure of materials at working temperature; The same caliber does not guarantee the same connection size and opening and closing capacity.

J641H-25C needs to be turned off after gas interruption. How should the actuator be configured?

The safety position required for the process in case of gas loss should be clarified first, and then the single or double acting scheme, output force or torque, and accessory circuit should be checked. You cannot select cylinders based solely on valve diameter, nor can you assume that all pneumatic configurations will close when there is a loss of air.

Selection and ordering information

Suggest providing the composition of the medium, design and operating temperature, maximum and normal pressure, flow range, pipeline standards, operating frequency, control signals, power or gas supply conditions, fail safe location, and environmental protection requirements. Fouten Flow Control (Jiangsu) Co., Ltd. will verify the caliber, material, seal, actuator, and accessory combination based on this, providing traceable basis for installation and maintenance.