FLOWX Engineer 86-21-54150349
Using pipeline to transfer liquid or gas has obtained rapid development in recent years. Valves used on long distance pipeline (long distance pipeline) are called pipeline valve. Pipeline valve (ball valve, gate valve, check valve and plug valve, etc.) is a kind of special valves to meet the special requirements and function of pipeline transport. For the pipeline ball valve, the technology standard API6D and international standard ISO 14313-14313 by the American petroleum institute. This kind of electric actuators has full size and low flow resistance, and has been rapid development for long distance pipeline valve; its actuator development trend has got the world’s attention.
2 Technical performances
Long distance pipeline’s working conditions are very bad, the installation places are located from the Arctic Circle to the equator, from the mountains to the ocean floor, from the plateau to the desert, meanwhile through the earthquake zone, swamp, permafrost, rivers, lakes and hills. Some pipeline valve has erection, some are buried underground, some are operated in the field, besides, there are many difficulties for maintenance and requires 30 years’ service life. General transport medium for long distance pipeline are mainly oil and natural gas, although after treated but its medium atill contains sulfur, impurities and foreign bodies. Therefore, more strict technical requirements are put forward for actuator development trend.
The strength and toughness
In addition to the internal medium pressure valve, it has to stand axial tension and stress causing by environment temperature change. When considered of landslide, land subsidence, material need be made according to the theory of fracture mechanics to consider its fracture toughness.
(2)The zero order
The ball valve requires zero level, in order to ensure effective truncation of downstream end of the line. Considering the influence that metal particles in the medium made to the zero order seal, we should do primary sealing forf metal to metal and secondary seal for PTFE/rubber and metal. Once the seal failure we should take emergency seal measures.
1. The fire safety and anti-static
The design of pipeline ball valve of pneumatic actuators should consider fire safety. Once the ball valve is on fire, the valve out leakage and inside leakage cannot exceeding the standards provided by API607.If sphere rub with material clamping, it may produce electrostatic.
(4) DBB function (Double Brock & Bleed)
During the valve cavity drainage, the actuator development trend is that the side seat on the downstream and upstream shall be cut off at the same time to ensure the safety of the emissions.
(5) Prevent the valve cavity pressure clamping
Whether the valve is in open or closed position, we shall prevent medium was holding in the valve cavity. If the medium is in holding position, we have to ensure to relief valve cavity automaticly. The maximum number of the valve cavity pressure cannot exceed the maximum of valve pressure rating of 1.33 times, external pressure relief valve diameter is DN15 or larger.
(6) The discharge
The actuator development trend is that valve cavity medium can be discharged, and we can do valve seal test online through the drain hole.
(7) Position indicator
Whether we do manual or power driving, there should have obvious valve position indicator to show that the valve is in open or closed position.