How to Correctly Select a Suitable Imported Valve

Imported valves mainly refer to valves from foreign brandimarily from Europe, America, and Japan. Representative brands include British Spirax Sarco, German LIT, Japanese KITZ, and American RETZ. The product types of vinly include imported ball valves, imported globe valves, imported control valves, imported butterfly valves, imported pressure reducing valves, imported solenoid valves, etc. Furthermore, there are many parters such as product diameter, pressure, temperature, material, connection method, and operation method, so it is necessary to select a suitable valve based on actual needs and product characteristics. cle analyzes the specific selection of imported valves combined with the German brand LIT, which has received widespread customer praise:

I. Characteristics of Imported Valves include Usage Characteristics and Structural Characeristics

1. Usage Characteristics of Imported Valves

Usage characteristics determine the main performance and usage scope of the valve. These include: valve category (shut-off valves, control valves, sfety valves, etc.); product type (gate valve, globe valve, butterfly valve, ball valve, etc.); materials of main valve parts (valve body, valve cover valve stem, valve disc, sealing surface); valve transmission method, etc.

2. Structural Characteristics

Structural characteristics determine the structural features related to the installation, maintenance, and upkeep f the valve. These include: valve structural length and overall height; connection form with pipelines (flange connection, threaded connection, clamp connection, external thread connection, welding end conntion, etc.); sealing surface form (insert ring, threaded ring, hardfacing, spray welding, valve body itself); valve stem structure form (rotary stem, rising ste), etc.

II. Steps for Selecting a Valve

Clarify the purpose of the valve in the equipment or installation, and determine the working conditions of the valve: applicable medium, working press temperature, etc. For example, if you want to select a German LIT globe valve, confirm that the medium is steam, the working pressure1.3 MPa, and the working temperature is 200°C.

Determine the nominal diameter and connection method of the pipeline connected to the valve: flange, threaded, weldi For example, when selecting an imported globe valve, confirm that the connection method is flanged.

Determine the operation method of the valve: manual, electric, electromagnetic, pneumatic r hydraulic, electro-hydraulic linkage, etc. For example, selecting a manual globe valve.

Determine the material of the valve body and internal parts based on the medium conveyed by he pipeline, working pressure, and working temperature: cast steel, carbon steel, stainless steel, alloy steel, acid-resistant stainless steel, gray cast iron, malleable cast iductile iron, copper alloy, etc. For example, selecting cast steel material for the globe valve.

Select the type of valve: shut-off valves, control valves, safety vaves, etc.

Determine the valve form: gate valve, globe valve, ball valve, butterfly valve, throttle valve, safety valve, pressure reducing valve, steam trap, etc.

Determie parameters: For automatic valves, first determine the allowable flow resistance, discharge capacity, back pressure, etc. based on different needs, and then determine the nominal diameter of the pipethe diameter of the valve seat hole;

Determine the geometric parameters of the selected valve: structural length, flange connection type and dimensions, dimensions in the heigection after opening and closing, bolt hole dimensions and quantity, overall valve dimensions, etc.

Utilize existing data: valve product catalogs, valve product brochures, etc., to selectpriate valve products.

III. Basis for Valve Selection

The purpose of the selected valve, operating conditions, and operating control method;

Properties of the working medium: working pressure, working ture, corrosiveness, whether it contains solid particles, whether the medium is toxic, whether it is flammable or explosive, viscosity of the medium, etc.; for example, if intendito select an imported solenoid valve from German LIT, and the medium and environment are flammable and explosive, a ** solenoid valve is generally selected; another example iscting a ball valve from German LIT, where if the medium contains solid particles, a V-type hard-seal ball valve is generally selected.

Requirements for valve fluid characteristics: flowe, discharge capacity, flow characteristics, sealing grade, etc.;

Installation dimension and shape dimension requirements: nominal diameter, connection method and dimensions with the pipeline, shape dimension or weight limiations, etc.;

Additional requirements regarding the reliability, service life, and ** performance of the electric actuator of the valve product (Note: when selecting parameters, if the valve i be used for control purposes, the following additional parameters must be determined: operating method, maximum and minimum flow requirements, pressure drop under normal flow, pressure drop when closed, maximum and minimum in pressure of the valve).

Based on the above basis and steps for valve selection, to reasonably and correctly select a valve, it is also necessary to have a detailed understanding of the internal e of various types of valves, so as to make the correct decision on the preferred valve.

The final control of the pipeline is the valve. The valve closure member controls the flow ction of the medium in the pipeline, and the shape of the valve flow path gives the valve certain flow characteristics; this must be considered when selecting the valve most suitable for installation in the pipne system.

In summary, the key elements for selection are: determining the functional valve to be used, confirming the medium temperature and pressure, confirming the valve flow rate and required diameter, cong the valve material and operating method.