Generally, the selection of control valve is mainly based on the nature of the medium, process parameters, use requirements, etc.
1. The properties of the medium should be clearly attributed to which of the following:
(1) General fluids
(2) High viscosity, fluids containing suspended solids, fibrous and other fluids
(3) Toxic or expensive fluids
(4) Corrosive fluids
2. The process parameters should clearly belong to which of the following categories
(1) Low pressure, small pressure difference, large flow
(2) Medium pressure or low pressure, large differential pressure
(3) High temperature, high pressure, high pressure difference
(4) Temperature and temperature difference
a combination of the above categories or others.
3. The use requirements are a combination of one or more of the following
(1) The leakage is small or the plugging is required
(2) Good stability and easy maintenance
(3) Requirements for the weight and volume of the control valve
(4) Action speed requirements
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Identify the valve refurbishment method - Wuzhong instrument
1. Remove the nut and identification plate at the upper end of the valve stem, and look at the lock nut raw material inside, the raw material is brass, otherwise it is a counterfeit product.
2. Look at the steel seal, the valve steel seal is pressed on it before the valve has passed the heat treatment, and the professional steel seal skills are used.
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Precautions for valve installation - Wuzhong instrument
1. Before the device, check whether the valve has notched parts, whether the type is correct, whether there are debris in the valve body, and whether the muffler is blocked.
2. Close the valve and cylinder.
3. Device the cylinder on the valve, the direction of the equipment is parallel or straightened with the valve body, and check whether the screw holes are aligned.
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Wuzhong instrument low-power electromagnetic micro-displacement controller
A low-power electromagnetic microdisplacement controller consisting of a coil backbone, a coil wound around a coil skeleton with a control circuit and a terminal block, and a coil core, characterized by:
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Check valve selection points - Wuzhong instrument
Check valve, also known as check valve, check valve, is a valve used to avoid the backflow of medium in the pipeline, belongs to a class of active valves, because the pump in the abort operation, the medium will flow backwards, if there is no device check valve at this moment, the water hammer effect will occur in the process of backflow, the pipeline ...
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Reasons and solutions for the loose closure of the valve - Wuzhong instrument
Valves often present some troublesome problems in the process of use, such as the valve is not closed tightly, not tight, so what should I do?
Under normal circumstances, if it is not tightly closed, first admit whether the valve is closed in place, if it has been closed in place, it still exists.
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Wuzhong instrument valve knowledge terms
1) General purpose valve (general purpose valve): a general term for a wide range of valves, also known as ordinary valves. It is not a valve for a specific condition and a specific purpose.
Although there is no clear definition of a universal valve, it mainly refers to a pressure below 2MPa, ...
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The steps and basis for selecting the valve - Wuzhong instrument
(1) Selection process
(1) Clarify the purpose of the valve in the equipment or equipment, and confirm the operating conditions of the valve: applicable medium, operating pressure, operating temperature, etc.
(2) Confirm the nominal diameter and connection method of the pipeline connected to the valve: flange, thread, welding, etc.
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The Importance of Equipment Lubrication - Wuzhong Instrument
1. Smooth mechanism
Smoothing is to add a smoothing agent between the two conflict surfaces of relative motion, so that a smooth film is formed between the two conflict surfaces, and the dry conflict appearance that is originally directly touched is separated, and the dry conflict is a conflict between the smooth agent molecules, so as to reduce the conflict and reduce wear, ...
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Wuzhong instrument - common industrial pipeline identification specifications and colors
First, the effect of pipeline identification
Why do you need to do pipeline identification?
Intent: To facilitate the identification of substances in industrial pipelines, ensure safe production, and avoid misjudgment in operation and equipment maintenance. Carry out ...
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Features of pneumatic regulating stainless steel butterfly valve - Wuzhong instrument
Product features of pneumatic conditioning stainless steel butterfly valves:
1. Simple, small size, light weight, small flow resistance, large flow coefficient and good sealing performance. Large conditioning range. It is the fulfillment unit of the instrument in the automatic control system.
2、 ...
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Wireless remote valve control system - Wuzhong instrument
1. System overview
The valve automatic control system controls the solenoid valve equipment placed in the field by announcing the instructions of the control service center in a wireless way, and then realizes the opening and closing of the solenoid valve, and the opening and closing status of the valve, the operation status, whether the equipment is online, historical data inquiry, etc.
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Turbine fixed ball valve standard execution suppression - Wuzhong instrument
The process of shell experiments and seal experiments done by turbine fixed ball valves in some artificial environments is as follows.
Double blocking and discharge function of turbine fixed ball valve: the turbine ball valve is fixed by using tension spring preload float valve seat, when the valve is in two different states, full open and fully closed, the fluid is ...
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Causes and solutions of internal leakage of safety valve jumping
First, there is a leak in the safety valve. The industry said that when there is a small leakage in the safety valve, it is generally not easy to find, but even a small leakage point will expand in the erosion.
The test method is to test ...
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The correct use of thermocouples can not only accurately obtain the temperature value and ensure that the product is qualified, but also save the data consumption of thermocouples, which can not only save money but also ensure product quality. Incorrect installations, errors such as thermal conductivity and time lag are the first errors in the use of thermocouples.
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Wuzhong instrument G1610 slag lock valve introduction
The slag lock valve (bucket valve) is specially designed for the complex working conditions of coal gasification, and is a special hard seal ball valve that can adapt to high temperature, high pressure and high wear resistance working conditions. The slag locking valve is mainly used to solve the problem of coal slurry feeding in the gasification unit and the common problem of medium scaling in the valves used in the black water process pipeline.
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Prevention and elimination methods of leakage on the sealing surface of valves
1. When the sealing surface is grinding, the grinding tools, abrasives, abrasive cloth and sandpaper and other objects should be selected in a reasonable grinding method, and the coloring inspection should be carried out after grinding, and the sealing surface should be free of indentations, cracks, scratches and other shortcomings;
Second, the connection between the valve stem and the closure should meet the planning requirements, and the top center is not suitable.
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Non-technical failure analysis of hard seal ball valve - Wuzhong instrument
From the perspective of product application, hard seal ball valve defects can be roughly divided into the following two categories: non-technical faults and skill defects. The following text mainly introduces the analysis and solution of non-technical problems of hard seal ball valves;
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The fastening nut on the handwheel, if found to be loose, should be ...
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