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Here are some main brief installation points of spring relief valve or spring safety valve we need to notice. Before installing spring relief valve, the first thing we need to pay attention to is to be sure to test the seal performance. If the relief valve leaks or the air cushion is broken, they are needed to be changed immediately accordingly. Then, it can be got the best use by all of us. The first premise is that the vertical installation is needed to be paid attention to for all parts of the relief valve in the process of relief valve installation. And, the installation angle should be precise and formal. Of course, tools should be used to make the corresponding auxiliary. Then, it can make the whole installation process smoothly and effectively. Second, it should be noticed that it is not allowed to give pressure on the exit of the relief valve during the installation of relief valve. It’s better to let it empty directly so that the relief valve can work effectively. Then, people can get it best effect, have better use experience and install the relief valve in place. Third, it should be noticed that the operator had better wear the corresponding gloves tools on their hands to avoid that oil pollute relief valve. The oil pollution can affect the sealing effect of relief valve. At same time, it also may lose the whole service life of the relief valve. Therefore, it is a good way to let the operator wear the gloves tools.

In 2012, we attended the 19th International Oil&Gas Industry Exhibition & Conference (OSEA). We meet our customers and new friends in the exhibition. After candid talks with them, Dervos gets a lot of valuable suggestions and feedback. We will invest more in technology in butterfly valves and marine valves. Meanwhile, gate, globe, check and ball valves remain our major products. In the year to come, we are planning to participate in more overseas exhibitions. News will be updated. Thanks for your attention to Dervos.

Gate valves are the main components of the oil (gas) wellhead, several kinds of the common faults in the use of the common faults as follows. 1. Leakage between gate valve and gate valve junction First, check whether valve and gate valve connecting bolts are tight or not, if not tighten, its seal ring and the flange seal groove surface if not sufficiently connected, often lead to leakage. Check bolt and nut orderly, tighten all bolts, until the compress seal ring. Second, check the size and accuracy of the surface of the seal ring and the flange seal groove, if the sealing contact surface has wrong size or too rough, to repair or update it. Also check whether the contact surface of seal ring and the flange seal groove exist a little bit erosion, sand hole, sand holes, or impurities, or other defects, if any, should carry on the corresponding welding, repair, or cleaning up. 2. Leakage from bonnet Bonnet leakage, this failure phenomenon often occurs in the leakage of packing seal. First, check seal if fitting is correct, whether it is suitable for seal groove, if there is such a problem, replace the sealing ring or repair the seal groove. Second, check if seals have burrs, fracturing, and twist off, if any, replace the seals. Then, check if the surface of sealing groove seal is rough or have other defects, if there is a defect, eliminate the defects or update the damaged parts. Bonnet or scaffolds by compression seal packing, should check the installation of the packing case, if find packing installed upside down, should remove, carry out in accordance with the correct way to install. Pay special attention to the surface of packing seal joint. Finally, check if the precision of the contact surface of seal fittings meet the requirements. 3. Leakage from valve body cavity In the process of casting, sometimes valve body may appear casting defects, such as sand holes, sand hole. Although it is difficult to find in the process of machining, once the pressure put on the valve body, hidden casting defects will be exposed. If there is this kind of situation, welding, repairing or updating it. 4. Leakage from valve seat and valve plate Leakage occurs in valve seat and plate, which is the most common phenomenon among the installation or maintenance of gate valves. Generally this can be divided into two kinds: one is leaking in seal surface; the other is leaking in seal root. Above all, check the seat and the precision of the sealing contact surface of valve plate. The sealing surface needs grinding, if there is rough surface, remove and grind it again. Second, check whether there are pitting, indentation, sand holes, cracks and other defects the sealing surface, if in this case, replace valve seat and valve plate. For the valve seat with compression spring, should check whether the pressure spring elasticity is conform to the requirements, if less resilient, update the compression spring. Besides, check if T-shape coupling place of valve plate and valve ste...