Stainless steel valve manufacturers share most valve selection steps
by:AIRWOLF2020-05-22
Stainless steel valve manufacturers share most valve selection steps of valve characteristics generally has two kinds: use characteristics and structural characteristics.
1.
Features: it determine the main use of performance and use scope of the valve, belongs to the valve using feature category with valves (
Closed valves, regulating valves, safety valves, etc. )
;
Product type (
Gate valve, globe valve, butterfly valve, ball valve, etc. )
;
Valve main parts (
The valve body, valve cover, stem, disc, seal face)
The materials;
Valve drive way, etc.
2.
Structural features: it determines the valve installation, maintenance, maintenance methods such as some of the structural characteristics, belongs to the structural characteristics are: the valve and overall height, length and the structure of pipe connection (
Flange connection, threaded connections, clip connection, external thread connection and welding end connection, etc. )
;
In the form of sealing surface (
Insert, thread ring, welding, spray welding, the body body)
;
Stem structure (
Rotating rod, lifting lever)
And so on.
Most valve selection steps and basis: 1.
Choose the step (1) clear valve used in equipment or devices, valve operation conditions were determined: suitable medium, working pressure, working temperature and so on.
(2) to determine the pipe connected to the valve nominal pipe diameter and connection mode: flange, threaded and welding, etc.
(3) determine the operation of the valve mode: manual, electric, magnetic, electrical and pneumatic or hydraulic linkage or electro-hydraulic linkage, etc.
(4) according to the pipeline medium, working pressure, working temperature to determine the selected valve shell and internal parts of material: gray cast iron, malleable cast iron, ductile iron, carbon steel, alloy steel, stainless acid-resistant steel, copper alloy, etc.
(5) determine the type of valve, gate valve, globe valve, ball valve, butterfly valve, throttle valve, safety valve, relief valve, steam trap, etc.
6. Determine the parameters of the valve: for the automatic valves, according to different needs to allow flow resistance, discharge capacity, back pressure, etc. , to determine the nominal pipe diameter and the diameter of the valve seat hole.
All landowners determine the geometric parameters of chosen valve: structure and size, length, the flange connection after the opening and closing valve of the size of the height direction, connection bolt hole size and quantity, the whole valve installation dimensions, etc.
End use of the existing data: valve catalogue, choose proper valve products such as valve products sample.
2.
Chose the valve on the basis of the understanding of the valve steps at the same time, should also learn more about choosing the basis of the valve.
Selected valve (1) the way of use, the working conditions of use and operation control.
(2) the nature of the working medium, working pressure, working temperature, corrosion performance, whether or not containing solid particles, the medium is toxic, whether it is flammable, explosive medium, medium viscosity and so on.
(3) the requirement: the characteristics of the valve fluid flow resistance, discharge capacity, flow characteristics, sealing level and so on.
(4) the installation size and shape size requirements: nominal diameter, and pipeline connection and the connection size restrictions on the size or weight, appearance, etc.
5. The valve product reliability, service life and the additional requirements of explosion-proof performance such as electric actuator (
Should be paid attention to in the selected parameters: if the valve to be used for control purposes, must determine the following additional parameters: the operation method, maximum and minimum flow, normal flow pressure drop, the closing of the maximum and minimum pressure drop and valve inlet pressure)
。
Choose according to the above the basis of the valve and steps, reasonably and correctly choosing valve must also know about the internal structure of all kinds of valve in detail, in order to make the right of priority selection of valve choice.
The ultimate control of pipeline is the valve.
The valve opening and closing a control flow of the medium in the pipe bundle, the shape of the valve port valve have a certain flow characteristic, when choosing pipe system is most suitable for installation of the valve must consider this.