News-Zhengnan Valve Co., Ltd

2024-09-30

What is the difference between clamp butterfly valve and flange butterfly valve

There are significant differences between clamp type butterfly valves and flange type butterfly valves in terms of connection methods, installation and maintenance, structural characteristics, sealing performance, applicable scenarios, and cost prices, as follows: 1. Connection method: Clamp on butterfly valve: There are no flanges at both ends of the valve body. The valve is clamped between the flanges of the two pipelines using double headed bolts, and the sealing is achieved by tightening the bolts. Flange butterfly valve: The valve body is equipped with flanges at both ends, which are directly connected to the pipeline flange through bolts. A sealing gasket or rubber ring is used in the middle to enhance the sealing performance. 2. Installation and maintenance: Clamp on butterfly valve: easy and fast installation, compact structure, and small space occupation; But if there is a problem with one sealing surface during maintenance, it is necessary to dismantle two pipeline flanges for inspection, which is more complicated to operate.

2024-09-30

Advantages and maintenance of three-way ball valves

Advantages and maintenance guide of three-way ball valve 1、 Core advantages 1. Multi channel flexible switching L-shaped channel: realizing two in and one out (such as A → B or A → C), suitable for medium distribution or switching scenarios, such as raw material switching in chemical pipelines. T-shaped channel: supports three-way flow, can complete medium mixing (such as A+B → C), diversion or full on/off, commonly used in systems that require dynamic adjustment, such as cold and hot water mixing in HVAC systems. Advantages: Single valve replaces multi valve combinations, reduces the number of pipeline fittings, saves space, and simplifies operations. 2. Efficient sealing performance Material: Made of PTFE, PPL or metal hard seal, suitable for high temperature (-19 ° C)

2024-09-30

Classification, characteristics, maintenance, and repair of hydraulic control valves

Classification, characteristics, maintenance and repair guidelines for hydraulic control valves 1、 Classification system Hydraulic control valves form diverse types through structural and functional combinations, with the core classification logic as follows: 1. Segmented by purpose Water level control valve: applied in scenarios such as water tanks and water towers, it maintains stable liquid level by linking valve opening and closing through floating balls or pressure sensors. Pressure reducing valve: reduces high-pressure fluid to a set low pressure and automatically stabilizes pressure based on the energy of the medium. Typical

2024-09-30

The difference between eccentric hemispherical valve and fixed ball valve

There are significant differences between eccentric hemispherical valves and fixed ball valves in terms of structural design, sealing performance, application scenarios, and operational characteristics. The following is a specific comparative analysis of the two: 1、 Structural Design 1. Eccentric hemispherical valve: The eccentric hemisphere valve adopts an eccentric design, and there is an eccentricity between the valve shaft and the centerline of the hemisphere. This design ensures that the contact between the ball core and the valve seat only exists at the moment of closing and opening the valve, thereby reducing the wear of the valve core and valve seat. The spherical surface of an eccentric hemispherical valve usually does not have a V-shaped port, and its sealing surface design focuses on achieving tight cutting.

2024-09-30

Repair and maintenance methods for check valves

Repair and maintenance methods for check valves 1、 Repair method 1. Leakage fault handling Seal inspection and replacement: If the seal (such as O-ring, gasket) ages, cracks or is damaged, it is necessary to replace it with a component that matches the original specifications in a timely manner. Valve disc and valve seat repair: Check the mating surface between the valve disc and valve seat. If there is wear, scratches, or corrosion, use grinding tools to repair the surface flatness or replace damaged parts directly.

2024-09-30

What specific occasions are forged steel ball valves suitable for?

Forged steel ball valves are suitable for the following specific occasions: 1. Oil and gas industry: Long distance pipeline transportation: Forged steel ball valves are widely used in long-distance transportation pipelines for oil and natural gas, which can withstand high pressure and harsh environments, ensuring the safety and stability of the transportation process. Urban gas pipeline system: in urban gas

2024-09-30

Installation process of threaded ball valve

The installation process of threaded ball valves requires following certain steps to ensure their correct installation and good operation. The following is a detailed introduction to the installation process of threaded ball valves: 1、 Preparation before installation 1. Check the pipeline: Ensure that the pipelines before and after the ball valve are ready, and that the pipelines are coaxial, with the two flange sealing surfaces kept parallel. The pipeline must be able to withstand the weight of the ball valve. If the pipeline cannot support it, please install appropriate support structures on the pipeline. 2. Cleaning pipelines: Use compressed air or appropriate cleaning tools to blow clean the pipelines before and after the ball valve, removing oil stains, welding slag, and other impurities. This helps to reduce wear and leakage of the valve during use.

2024-09-30

Working principle and maintenance method of hard sealed butterfly valve

Working principle and maintenance method of hard sealed butterfly valve 1、 Working principle The hard sealed butterfly valve achieves the opening, closing, or adjustment of pipeline media by rotating the butterfly plate. Its core structure and working logic are as follows: 1. Structural composition Butterfly plate: a disc-shaped opening and closing component that rotates around a fixed axis inside the valve body (0 °~90 °) to control the flow of the medium. Valve body: cylindrical channel, providing a medium flow path, and forming a sealing surface with the butterfly plate inside.

2024-09-30

Why is it necessary to specify a sealing device for gate valves and globe valves

Gate valves and globe valves are required to have upper sealing devices, mainly based on the following considerations: 1、 Prevent medium leakage and protect the filling material Prevent medium leakage: When the gate valve and globe valve are closed, the valve stem is in a stationary position. If there is no upper sealing device, the medium may penetrate upwards along the gap between the valve stem and the valve body, causing the medium to leak out. The upper sealing device can effectively prevent medium leakage, ensuring the working performance and safety of the valve. • Packing protection: The packing box is usually made of flexible materials such as asbestos, polytetrafluoroethylene, etc