Combet Valves always makes sure their workshop is a clean and organised work environment . π www . valve-world . net Valve World August 2023
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The valves have a three-piece design , and of those parts , only the body group is truly proprietary to Combet Valves . Any end connection , such as butt welds , flanges and hammer unions can be fitted onto the valve , depending on the client ’ s wishes . Weld ends are supplied in the client ’ s piping material and schedule size , so there is no need for the client to make new welding procedures . “ On top of that , the ends can be welded while unconnected to the valve , so no heat will be transferred into the valve , which could otherwise damage the seats and seals . After welding , the valve can easily be inserted between the end connections of the client ’ s piping . Just rotate the valve into position , tighten the bolting and you ’ re done ,” Matthieu says . “ With our valves , the clients also face a lower pressure drop , as our ball valves ’ ID closely matches the ID of the piping systems clients use ,” says Benjie . “ We can adjust the valve ’ s length , materials and end connections . Our compact valves are very flexible . They are small and light , and the torque to open them is similar to that of a traditional trunnion design ,” Matthieu explains . As the dimensional envelope of their compact valves is identical to those of other manufacturers , clients still have the option to switch compact valves after the end connections have been welded to the pipe . Other than that , Benjie adds that they can also meet the dimensional envelope of conventional valves , as they can customise the end connections in such a way that the compact valve takes up the space of a conventional valve envelope . Combet Valves is thus able to serve clients quickly if they need short deliveries for a traditional valve space envelope . The Combet floating ball valve has a unique seat carrier design that has overcome the challenges of low-pressure positive shut-off and high operating torques where traditional floating ball valves might struggle . The ball moves between the two seats and is bidirectional . When pressure is applied , the ball is pushed into the seat , causing that side to seal . The seat insert and seat carrier work in tandem with the L-seal that only allows pressure to pass in one direction . In Combet ’ s design , the seat carrier acts as an internal bypass mechanism that equalises pressure at the moment the valve is opened , which reduces the operating torque . The way their bypass works is that there are small holes in combination with a loose seat , which causes pressure to be equalised when the valve is opened . Usually , floating ball valves have a superior seal , but are harder to open because of frictional forces . Combet Valves ’ bypass design circumvents that issue . “ When looking for a valve solution to deal with high pressure , companies usually select trunnion valves or metalseated valves . Our floating ball valve can handle those pressures as well . They ’ re also more cost-efficient . Our valves only consist of seven parts , while trunnion designs usually have fifteen to twenty , making them more expensive ,” Matthieu explains . “ The loose seat design makes the valves also easy for field repairs where other designs need to be sent to special valve repair shops or even back to the manufacturer . Our valves can easily be taken out of the pressure line and all internals can be replaced quickly with a simple repair kit , after which the valve can be mounted back in the pressure line to continue operation .” Another advantage is that this valve has good low-pressure sealing with a much larger seat sealing area , Benjie continues . The seat assembly with the seat carrier is energised like the trunnion valve , but with an elastomeric L- seal . Instead using PTFE , like for traditional floating ball valves , we use an acetal co-polymer or peek with an elastic memory . The floating compact ball valve seat design will seal in low-pressure applications on the inner diameter of the seat insert , creating a line seal and sealing bubble tight , even in helium gas testing . In a high-pressure differential application , the ball is pushed in the seat . Pushing the ball into the downstream seat will follow the full geometry of the seat insert , creating a very large ball / seat
Combet Valves always makes sure their workshop is a clean and organised work environment . π www . valve-world . net Valve World August 2023
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