Pneumatic ball valve selection guidance
Selection main point: pneumatic ball valve selection should be followed in the safety, reliability, applicability, economy four principles and six aspects of site condition (pipe parameters, medium parameters and pressure parameters, power supply parameters, action mode, special requirements).
Selection principle: safety: namely selection should first consider to life and property safety, especially of inflammable and explosive occasions! Reliability: action not reliable pneumatic ball valve will damage system of the other element. Applicability: selection must consult experts, such as buy a cryogenic valve used for steam, equal to the FeiPin! Economy: that is used for low temperature medium are not choose high temperature, because of the high temperature high cost!
Selection basis:
One, according to the pipe parameter selection pneumatic ball valve: size size (namely DN), interface mode 1, determine size size the most simple method is directly in accordance with the field pipeline diameter can be up to. According to the site or pipeline within the medium flow on the size of the company with the pneumatic ball valve Kv value contrast sure. 2, interface mode, general > (to choose flange interface, acuities can be (according to the user's free choice.
Second, according to the medium parameter selection pneumatic ball valve: material, temperature group 1, corrosive medium: appropriate chooses plastic king pneumatic ball valve and the whole stainless steel; For a strong corrosive medium to must choose the isolation diaphragm, such as: OSA70. Neutral medium, and appropriate chooses copper alloy for valve shell material pneumatic ball valve, otherwise, valve shell has a tendency to rust dust fall off, especially action not frequent occasion. Ammonia valve will not be using copper. Used for drinks, milk process pipe are to USES the food grade stainless steel material pneumatic ball valve. 2, high temperature medium: medium temperature elected in the pneumatic ball valve allows scope. If hot water, steam, heat conduction oil should choose to use high temperature resistant electromagnetic coil and sealing material varieties, and to choose piston structure types of. For example: 200 ℃ steam elected OSA73 or OSA86 series stainless steel material is qualitative, the choose of copper is not good, because when the temperature more than 170 ℃ copper expansion coefficient and pneumatic ball valve piston component and piston cavity tolerance contradiction, which can lead to action hard. 3, medium state: to have gaseous, liquid or mixed state, this should choose different kinds of pneumatic ball valve, that is used for gas or used in different liquid medium, medium form to indicate, or against valve performance is stable. 4, medium viscosity: usually in 50 CST the following can be arbitrary choice, if more than this value, should choose high viscosity pneumatic ball valve. 5, medium cleanness: if the medium containing a small amount of tiny impurity optional diaphragm structure, but if impurities are too large, should be in pneumatic ball valve to be installed ahead of filter.
In short, economy not only refers to the price of a product, but the product cost performance comprehensive cost price. |
