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Type Analysis of Check Valves

What is a check valve?

A check valve is a valve that relies on the flow of the medium itself to automatically open and close the valve disc. It is used to prevent the medium from flowing back and is also called a non-return valve, a one-way valve, a reflux valve, and a back pressure valve.

A check valve is a valve that can automatically prevent fluid from flowing back. The valve disc of the check valve opens under the pressure of the fluid, and the fluid flows from the inlet side to the outlet side. When the pressure on the inlet side is lower than that on the outlet side, the valve disc automatically closes under the action of factors such as fluid pressure difference and gravity to prevent fluid backflow.

Classification of check valves

Bronze check valve and brass one way check valve are generally divided into lift check valves, swing check valves, butterfly check valves, and diaphragm check valves, etc.

The structure of the lift check valve is generally similar to that of the globe valve. Its valve disc moves up and down along the line in the passage, with reliable operation but high fluid resistance, and is suitable for small-diameter occasions. The lift check valve can be divided into straight-through and vertical types. The straight-through lift check valve can only be installed in horizontal pipelines, while the vertical lift check valve is generally installed in vertical pipelines.

The valve disc of the swing check valve rotates around the axis. Its fluid resistance is generally smaller than that of the lift check valve, and it is suitable for larger-diameter occasions. According to the number of valve discs, the swing check valve can be divided into single-disc swing check valve, double-disc swing check valve, and multi-disc swing check valve. The single-disc swing check valve is generally suitable for medium-diameter occasions. When a single-disc swing check valve is selected for a large-diameter pipeline, in order to reduce water hammer pressure, it is best to use a slow-closing check valve that can reduce water hammer pressure. The double-disc swing check valve is suitable for large and medium diameter pipelines. The wafer-type double-disc swing check valve has a small structure and light weight, and is a type of check valve that is developing rapidly. The multi-disc swing check valve is suitable for large-diameter pipelines.

The structure of the butterfly check valve is similar to that of the butterfly valve. Its structure is simple, and the flow resistance and water hammer pressure are relatively small.

In Carbo bronze valve factory, There are various structural forms of diaphragm check valves, all of which use a diaphragm as the opening and closing element. Due to its good water hammer resistance, simple structure, and low cost, diaphragm check valves have developed rapidly in recent years. However, the use temperature and pressure of diaphragm check valves are limited by the diaphragm material.

Before we start our daily work, we put qualified and unqualified products on the pressure tester to check whether the equipment is working properly. Each worker should conduct self-inspection. Products can only be assembled after the first product is randomly inspected every two hours to check the assembly performance of the workers. We have two casting lines with an annual output of 80 million tons of billets. All materials are tested by the laboratory, and the test reports are kept for three years for traceability. Welcome to inquire.