Statesman
Mechanical
- Jul 26, 2002
- 15
Hello Gents,
We are replacing a water injection spool directly from HP pump outlet. (Fluid:Water, Flow: 700 M^3/H, Diff Head:737M Outlet size 8"
When we have removed the Existing 1500# Rated spool (LTCS Astm A333-6 SMLS) we have found that the RF Flange that mates to the outlet of the pump (RF) has had its bore 'opened out', and hence its face width reduced slightly. It is not been a tapered bore that you would expect, maybe to allow for any bore missalingment but an actual machined preparation (The only thing that can help me explain it is like an internal 'J' type weld prep)
My thinking is that this opening out of the internal bore would be causing eddys,cavitation etc. and therefore erosion of the pipework.(Which we are now witnessing) My question to the forum is, Why would such an internal machining be employed, surely when mating to an HP pump outlet, it is preferable to use an identical flange with identical (as near as damn it) bore to facillitate a good flow of fluid. If this was a one-off I wouldnt be too concerned, but when we removed another spool, the internal of the mating flange had also been machined that way. (There is no note of why on the PID or Fabrication iso) My concern is that we will replace this spool with a standard RFWN but may be missing out on some fundamental benefits of the original design.
We are replacing a water injection spool directly from HP pump outlet. (Fluid:Water, Flow: 700 M^3/H, Diff Head:737M Outlet size 8"
When we have removed the Existing 1500# Rated spool (LTCS Astm A333-6 SMLS) we have found that the RF Flange that mates to the outlet of the pump (RF) has had its bore 'opened out', and hence its face width reduced slightly. It is not been a tapered bore that you would expect, maybe to allow for any bore missalingment but an actual machined preparation (The only thing that can help me explain it is like an internal 'J' type weld prep)
My thinking is that this opening out of the internal bore would be causing eddys,cavitation etc. and therefore erosion of the pipework.(Which we are now witnessing) My question to the forum is, Why would such an internal machining be employed, surely when mating to an HP pump outlet, it is preferable to use an identical flange with identical (as near as damn it) bore to facillitate a good flow of fluid. If this was a one-off I wouldnt be too concerned, but when we removed another spool, the internal of the mating flange had also been machined that way. (There is no note of why on the PID or Fabrication iso) My concern is that we will replace this spool with a standard RFWN but may be missing out on some fundamental benefits of the original design.
