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Causes of Fracture of SS 304 Check Valves (Part Two)

1.4 Detection of non-metallic inclusions Samples were taken from the fracture of the valve, and after inlaying, grinding and polishing, they were observed with an optical metallographic microscope. The morphology of the non-metallic inclusions is shown in Figure 4. According to GB/T10561-2005 "Determination...

Causes of Fracture of SS304 Check Valves (Part One)

Abstract: The stainless steel 304 check valve on the production equipment of a company broke during use. The reasons for the fracture of the check valve were analyzed by means of macro analysis, chemical composition analysis, fracture analysis, non-metallic inclusion detection, metallographic inspection,...

The Sealing of Valves

The sealing of high-pressure globe valves In the production process of the high-pressure globe valve, in order to ensure the safety of its use, the technicians will reasonably select the sealing material, usually a metal, which can make the globe valve well sealed when it is closed. In this process,...

Common Causes of Failures of Valve Sealing

In the process of designing and producing high-pressure globe valves, check valves, low-pressure gate valves and other valves, there will be a certain impact on the production quality due to the influence of some objective factors. In order to improve the quality of high-pressure globe valves, check...

Treatment for Leakages of Grease Injection Holes Under Pressure

The valve cavity of the ball valve is working at high pressure for a long time due to the requirements of production for ball valves in operation. When the grease injection hole leaks, emergency treatment can usually only be carried out under pressure.   Repair under pressure Given the leakage...

Causes of Leakages of Grease Injection Holes of Ball Valves

Abstract: a leakage of grease injection holes of ball valves is one of the most common failures in pipelines in operation. The structure and principle of the ball valve's grease injection mechanism were analyzed; the causes of leakages of the ball valve's grease injection hole were discussed....

Measures to Failures of Valves

The failures of the valve mainly include failures caused by fractures, failures caused by corrosion, failures caused by leakages and failures caused by wear. The part with the most failure caused by fractures and corrosion is the valve stem, and the part with the most failure caused by leakages and...

The Main Reasons for Leakages of Valves and Their Measures

The main reasons for leakages of valves and their measures are as follows:   Leakages caused by falling off of the closing parts Reasons for falling off of the closing parts The operation is inappropriate, so that the closing part is stuck or exceeds the top dead...

The Work before the Valve Is Put into Use

Preventive measures before use Maintaining the valve before use can greatly reduce the probability of its failure in operation, and it is a necessary means to ensure the long-term and efficient operation of the valve. Therefore, for power companies, it is necessary to formulate a corresponding...

The Use and Maintenance of Pneumatic Valves

Pneumatic valves are valves driven by compressed air. When purchasing pneumatic valves, it is necessary to specify the specifications, types, and working pressure to meet the purchasing requirements, and they can be used to control various types of fluids such as air, water, steam, various...

The Application of Integral Sintered Tungsten Carbide to Wear Resistant Valves

1. Overview In polysilicon, coal chemical industry, power plant ash removal, mud and boiler slag discharge and other pipelines transporting materials, the valve's sealing part is subject to the sliding friction and wear of the sealing pair parts, withstands the high-speed impact of...

Valves Used for Water Supply Pipelines

1. The function of the valve in the water supply pipeline The water supply pipeline distributes the tap water from the water plant to thousands of households. Therefore, the water supply pipe is distributed in every corner of the city, and its length is from hundreds of...

The Lamellar Tearing of Valves

The lamellar tearing is a kind of internal low-temperature cracking. It is limited to the base metal of thick plates or the heat-affected zone of welding seams, which mostly occurs in "L", "T", and "+" shaped joints. It is defined as a kind of stepped cold...

Installation and Disassembly of Valves

1. Matters needing attention in maintenance and installation of valves are as follows: (1) The valve should be put in a dry and ventilated room, and both ends must be sealed to prevent dust. (2) If the valve is kept for a long time, it should be checked regularly and oiled on the...

The Analysis and Research on Test Methods of Ball Valves Used in Chemical Plants

The applicability of the current common test methods for ball valves is analyzed, and material tests, coating tests, tests of whole devices and simulation tests of working conditions are put forward; the test methods and processes are analyzed and discussed.   The...

How to Install the Sealing Gasket for the Valve?

Sealing gaskets are frequently used sealing spare parts for machinery and equipment, which are materials that play a sealing role. From this definition, it is not difficult for us to know how important a gasket is. Therefore, how to install a gasket is worthy of our attention....

Iron-based Alloy Surfacing Processes for Sealing Surfaces of Nuclear Valve Bodies (Part Two)

3. Quality control 3.1 Inspection before welding According to the metallographic analysis, impurities such as S and P in the base metal will be transferred to the surfacing layer in the surfacing process, and iron-based alloys are surfaced on the austenite matrix. The thermal...

Iron-based Alloy Surfacing Processes for Sealing Surfaces of Nuclear Valve Bodies (Part One)

Abstract: The reasons for the quality problems in the iron-based alloy surfacing on the sealing surface of the nuclear manual valve body are analyzed, and the quality control measures of the surfacing layer of the valve proposed after changing the surfacing process parameters and evaluating the...

An Introduction to a Valve

A valve is a control component in the fluid conveying system, which has the functions of diversion, cutoff, regulation, stabilization, prevention of reverse flow or overflow and pressure relief. As early as 4000 years ago, humans have tried to use valves. In the process of making salt in ancient...

Operation of Check Valves

Operating check valves should avoid the occurrence of excessively high impact pressure and rapid oscillation of the closing part of the valve due to the closing of the valve. In order to avoid the excessively high impact pressure caused by the closing of the check valve, the valve must be closed quickly...