Recent content by gustorf

S&D means seat and disk. ask Noreva for a quotation. www.noreva.de

Thanks NGiLuzzu! NEL Scotland can only do pressure loss testing as BHR in the UK or Stuttgart University in Germany or Utah University in the US. No one can do dynamic testing = water hammer effect simulations on check valves. Kind regards gustorf

In the old days the Delft Hydraulics Institute in the Netherlands used to do large size check valve testing on pressure loss and dynamic behaviour. Is there globally ANY test labaratory available that can do dynamic behaviour testing of valves DN 600?

I would say - No.

Sounds to me similar to a Flowserve/Calder DWEER energy recovery System Service. Noreva has installed some 500 valves (6in) in 2004 that have seen 1 Mio cycles annually. Feel free to contact Noreva for Details.

Hello. Has anyone experience with weld repairs on martensitic stainless steel castings ASTM A 743 CB 30 (Or material grade GX22CrNi17+QT = 1.4059 in EN Terms)? As the parts are final machined now, we are looking for procedures WITHOUT PWHT. So far we are used to simply scrap the parts when we...

You may also look at it from another angle: There is nowhere mentioned, when the 15 seconds have to START. So it's up to you during testing to ask for 10 minutes stabilizing of pressure, before you start counting the 15 seconds....

Ehtisham, I can only repeat my message: Go to Goodwin UK or Noreva Germany as they have a wide range of dual plate and nozzle check valves already TAT approved. This should make Shell happy!

Springs typically show a wide range of tolerances which I would never use for calculation of cracking pressures. The manufacturing of springs is not a very precise mode without having any other method of adjustment in the valve itself. gerhardl is right, there are many factors that count like...

Goodwin UK and Noreva Germany have a lot of Shell TAT approvals for dual plate and axial check valves.

Govindarasu, I can agree to 99% of the previous messages. As I work for Noreva, I have to disagree to Machiel's last statement "cheaper ring disk check valve" :-) The ring disk design has basically been invented 1935 and is still the best combination of non-slam perfomance and low head losses...

Goodwin UK (The leading manufacturer of dual plate check valves) provide a lot information in their brochure, you may want to look at: http://www.checkvalves.co.uk/brochure_downloads.html If you care for pressure loss, try out nozzle check valves as supplied by Goodwin or Noreva.

nmiller127, Thanks for the idea, I was thinking about the same, but check valves of different designs in operation show cracking pressures of approximately 105 to 110% of the operating or closing pressure. (Rule of thumb) This is a known rule of thumb to piping engineers which normally is not...

Thanks, hydtools, very useful. gerhardl, we have done all what you have recommended. Your statement about competitors is too true, unfortunately. It happens all the time to us. We have a very long great business relationship with the customer, they know our products since decades, but... The...

Thanks stanier and gerhardl. The story behind it is: A big German compressor manufacturer (SieXXXX) is evaluating the designs and layouts of their compressor units including surrounding components like check valves, isolating valves and syfety valves, etc. Based on sub-suppliers indications of...