Ball valves can be roughly points and 19 categories, floating ball, fixed ball valve, metal hard seal ball valve, V type ball valve, wafer ball valve, insulation ball valve, pipeline ball valve, rail ball valve, jacket type ball valve, pigging valve, high-pressure forging ball valve, tee (stone) ball valve, threaded ball valve, integral ball valve, low temperature ball valve, corrugated pipe valves, eccentric half ball, all welding ball valve, special ball valve, etc.
Type O ball valve adopts float type structure, ball core is precision castings, looks hard chromium plating processing, metal or seat is enhanced ptfe materials, flow crossing and pipe size is same, circulation ability is great, flow resistance is tiny, closed without leakage, generally do switch valve using, especially suitable for high viscosity, containingfibres, granular medium.
V type ball valve USES stationary structure, ball core on opened a v-shaped incision, can achieve proportional adjustment, flow characteristic for approximate percentage.
Ball valve applicable range is very wide, ball valves can be applicable to:
1, nominal diameter from 8mm to 1200mm.
2, nominal pressure from the vacuum to 42MPa.
3, working temperature from - 204 ℃ ~ ℃ 815.
Especially in petroleum, chemical, metallurgy, and other departments, in inflammable, explosive medium equipment and pipe system in use soft sealing ball valves, more should note refractory and fire prevention.
Usually, in double place regulating sealing performance strictly, mud, wear, shrink mouth channels, on-off movement.ball quickly (1/4 turn on-off), high voltage globe (differential pressure big), low noise, furious hole and gasification small leakage phenomenon, into the atmosphere, operating torque is little, fluid resistance small piping systems, recommend using ball valve.
Ball valves also applies to light structure, low voltage globe (differential pressure small), the corrosive fluids piping system.
In the low temperature (cryogenic) device and pipe system in also can choose ball valve.
In the requirement has regulation performance, needs to choose belt v-shaped openings of special structure ball valves.
In petroleum, petrochemical, chemical, electric power, city construction, the working temperature in 200 ℃ above piping systems can choose the metal to metal sealing ball valves.
In metallurgical industry oxygen pipe system in use to pass strict defatted processing ball valves.
In the pipeline and gas transmission pipeline to the competent line when buried in the underground, need to use full-bore welding type ball valve.
Ball valves in irrigation system is often applied, basically use in tubes inlet. Ball valve simple structure, small volume, the flow resistance is small, defect is opening or closing fast, can be in pipeline middle water hammer (pipe flow velocity in the pressure when suddenly changes will rise). So in ZhuGanGuan on unfavorable use ball valve, usable in in dry and tubes or its end be blunt washing with, washing drainage effect is good.
Ball valve selection for principles:
1, oil and gas transmission pipeline competent line, need cleaning, and for buried in the ground, the choice of sizes, full of welded structure ball valve, Buried in the ground, choose full-bore welding connection or flange connection ball, Tubes, choose flange connection, welding connection, whole given.it or shrink diameter ball valves.
2, oil conveying pipeline and storage equipment, selects flange connection ball valves.
3, city gas and gas pipelines, choose flange connection and threaded connections floating ball valve.
4, metallurgical oxygen pipeline system, appropriate chooses through strict defatted processing, flange connection of fixed ball valve.
5, low temperature medium piping systems and devices, appropriate chooses plus bonnet low-temperature ball valve.
6, refining installation of catalytic cracking unit of pipeline system, can choose lifting lever type ball valve.
7, chemical system soda acid corrosiveness device and pipeline system, appropriate chooses austenitic stainless steel manufacturing, ptfe for seat sealing the stainless steel ball valve.
8, metallurgical, power system, petrochemical plant, urban heating system of high temperature medium pipeline system or device, can choose the metal to metal sealing ball valves.
9, need to adjust the discharge, can choose worm gear and worm drive, pneumatic or electric with v-shaped openings of regulating ball valve.