Detection instrument (component) and control valve selection principle - Wuzhong instrument

1. Confirm the working conditions: P1, △P, Q, T1, fluid characteristics, allowable noise, etc.; Select the appropriate ANSI pressure class for the body and trim requirements 2. Calculate the required initial Cv value, check the noise and cavitation levels 3. Select the type of trim of the control valve: if there is no noise ...

The angular displacement of the valve position detected by the valve limit switch box changes the transmission shaft through the coaxial adjacency or the reaction rod, so that the cam touches the miniature switch, so that the contact of the switch assembly is closed or disconnected, and the switching signal is transmitted to the outside through the terminal, and the passer is displayed on the spot. ...

1. Accounting for traffic Accounting for flow can also be determined by referring to the capabilities of fluid transfer machinery such as pumps and compressors. Sometimes, a combination of methods is used to determine. 2. Determination of the differential pressure (1) The two equipment with close distance between the front and back of the conditioning valve and the stable pressure are ...

The stem axis of the globe valve is perpendicular to the seat sealing face. The relatively short open or closed stroke of the valve stem and the very reliable blocking action make this valve very suitable for the blocking or adjustment of the medium and the economical application. ...

The commonly used medium for valve pressure testing is water, oil, air, steam, nitrogen, etc., and the pressure testing methods of various valves are as follows. (1) Globe valve and throttle valve For the strength test of globe valve and throttle valve, the assembled valve is usually placed in the pressure test frame, the valve disc is opened, and the medium is injected into the ...

Stainless steel globe valve is a kind of globe valve, the specific stainless steel raw materials are CF8, CF3, CF8M, CF3M, different raw materials are selected, can be separated from water, steam, oil, nitric acid, acetic acid, oxidizing medium, urea and other media. Stainless steel globe valves are divided into manual stainless steel shut-offs.

When the gate valve is closed, the sealing surface can only rely on the medium pressure to seal, that is, only rely on the medium pressure to press the sealing surface of the ram to the valve seat on the other side to ensure the sealing of the sealing surface, which is self-sealing. Most gate valves are forcibly sealed, that is, when the valve is closed, it is necessary to rely on external force to forcibly ...

1. Glander type This is the form that is used a lot. The same form can be different in many details. For example, in terms of hold-down bolts, it can be divided into T-bolts (for low-pressure valves with a pressure of ≤ 16 kg/cm²), stud bolts and loose joints. From the gland point of view, it can be divided into integral and ...

1. The safety valve should have the equipment to prevent the hammer from moving by itself and the guide frame to limit the lever from deviating, and the spring-type safety valve should have the equipment to raise the handle and prevent the adjustment screws from being twisted at will. 2. It should be installed straight in the pot merchant, the container ...

In the process control system, the control valve accepts the control signal of the control instrument, directly touches with the fluid, adjusts the flow of the fluid, and controls the flow, pressure, temperature, liquid level and other elements in the system, so it understands the fundamental structure and characteristics of the control valve, and selects it correctly according to the process conditions of the system. ...

G2010 ball valve for long-distance pipeline is designed for the transportation of long-distance pipeline media, which is a typical long-distance pipeline ball valve, which is suitable for various oil, natural gas, city gas pipelines, and can also be used in the equipment of general chemical products. The valve is completely in line with the United States Petroleum Institute API in terms of performance...

The selection of control valve is a very complex thing, in order to ensure the use of control valves, customers only need to provide process parameters and use requirements to valve manufacturers, because valve manufacturers have rich experience in valve use, so they can provide customers with the best cost-effective valve products. ...

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.

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.

1. The safety valve should have the equipment to prevent the hammer from moving by itself and the guide frame to restrain the lever from deviating, and the tension spring safety valve should have the equipment to improve the handle and prevent the adjustment screws from being twisted at will. 2. It should be installed straight in the pot merchant, the container ...

Load the organization The role of the loading tissue is to apply a downward loading force from the top of the pressure reducing valve. The loading structure of the FITOK pressure reducing valve is mainly the loading of tension springs. Tension spring loading has the advantage of reliability and low cost, and is the most versatile loading device in pressure reducing valves.

(1) The dispatching valve belongs to the on-site dashboard, and the standard working temperature should be in the field of -25-60 °C, and the air humidity should be ≤ 95%. If it is installed outdoors or in a high-temperature place, moisture-proof and temperature-reducing measures should be used. In areas where there is an epicenter, it is necessary to eradicate the source of vibration or improve vibration isolation measures. ...

The biggest difference between the electric single-seat conditioning valve and the electric sleeve conditioning valve lies in the performance and application, but both have their own advantages and shortcomings, and the advantages of one may be the lack of the other, which can complement each other and be used in different occasions. There is no difference in appearance, first of all, the two ...

The actuator of the control valve has pneumatic type, electric type and electro-hydraulic linkage type, and the pneumatic equipment is divided into barrier type and cylinder type. Depending on the action when the operating signal and the drive source disappear, the actuator has a forward type, a reverse type, a non-directional type, and a persistent type. The positive type is used in the operation signal and drive ...

1. The human element Because of the errors caused by human elements, including misreading, miscalculation and parallax. Misreading often occurs in measuring tools such as vernier rulers and centimeter cards. The vernier scale is likely to misread a small reading, such as 10.02 mm or 9.98 mm at 10.00 mm. Divide...