In recent years alot of research has been done in reducing shear forces in turbulent flow, specifically in valves and pumps. Typhonix AS has indeed been a leader in this research. Together with Mokveld (www.mokveld.com) they have developed a system in which the dispersed flow will have larger...
sdl:
Fully agreed sdl. southerton is referring to SIL so he is basically adressing safety. If components that make part of the SIL loop fail, I believe that they HAVE to be reported to the manufacturer as the operators log will have to show the cause of the failure!
In Germany, reporting of...
jsummerfield,
basically you are correct, but if the vendor has more than 10000 logged operational years, and only 1 warranty call ... then statisically the accuracy of the prediction would increase!
I'd recommend to talk to the vendors with ample operational years of experience that have taken...
Try the Mokveld as Sircrashalot has stated. Mokveld can even calcualte the pressure losses on mulit-phase flow conditions. Then they calculated the empirical erosion constant (see ISO 13703:2000)given you a "feeling" of the serverity of the application.
They have many check valves installed in...
The designer of the nozzle type non-slam checks can be found at www.mokveld.com, the TKZ-Y. I'd still say that they lead the market in the non-slam check valves.
Another one is from Stockham, the "noz-check"
If it is intended for reliability assessment / analysis the common control valves suppliers fail to give accurate reliability data. The best you will find is them promoting smart psoitioners claiming that htese enhance reliability, but no mention of statisticla reliability data of the valve...
For cage guided control valves it could cause bad performance as the dirt gets caught between cage and plug. Pending on the partical size it could also clog the cage.
For on off duty, if the seals are in the flow path it could cause premature sela failure.
I doubt if any supplier will give...
Does anyone have recent updated failure rates for ESD type ball valves, solenoid valves and quick exhaust valve ?
This is equired to be included in a fault tree analysis to determine valve PFD.
Thanks,
Part of determining the correct choice of final elements, the IEC 61508/61511 required that realiability calculations be done. These calculations require the 'Probability of Failure on Demand' whihc is a function of the certified failure rate and the proof test interval.
Hence the frequency of...
Thanks, its a start. But as a valve guy, I frequently get questions in which I am given only size and pressure of the dwnstream piiping. Valve noise pends on wt also and the std pipe tables only refer to size and sch (wt) but doesn't tell me the allowed pressure.
In case anything else come up...
Anyone know of a spreadsheet which can roughly calculated the required pipewall when pressure/temperature is inputted.
Materials used carbon steel, stainless steel and duplex.
Regards,
RobV
It seems that you may be encountering some form of pressure surges in the main pipework. Approximately 40% of safety relief valves in liquid lines Susceptible to surges exhibited unstable operation. This is a recognised problem which is often solved with a true liquid surge releif valve...
I've just finish a complex workbook with macro's to streamline the calculation process and my boss has asked me to put it up on hte intranet. However only a restricted amount of user are 'allowed' to have access to the module so I programmed a VBA macro to check user ID. The next step is to...
