Circulating Water Fibre System Problem

You do not give enough information. Your English is very sketchy, so I don't understand the problem very well.

Let me try this:

1. You have 8 pumps. True?
2. Each 135 MW unit requires 2 pumps. True?
3. The filter damage is only happening on the #8 pump. True?

How am I doing so far?

10 out 10 for effort in the face of adversity.

A picture speaks louder than thousand words. Why don't you post a line diagram indicating the positions of valves & pumps. Valves for fibre filter are damaging, not the fibre filter itself which may be weaker than valves.

Reason may be vapour lock. But to give conclusive answer, provide following information also:

1. Fluid temperature

2. suction & discharge pressure and NPSH

3. Type of valves, Nos installed for each pump/filter

4. Location of vents in the piping system

vent line is provided near water box of condenser and water temperature near about 32oC and water pressure maintained 1kg/cm2,valve made of cast and dia300mm and pn10.during stopping of pump valves of unit 8 fibre filter inlet got damaged.pump capacity 15600m3/hr

Figure posted is not legible and clear. Can it be bigger & bolder. I understand that eight circles on top are 8 pumps (but not named 1 to 8), and four units are at bottom (but named different than 1 to 4). I still have following questions to correctly understand your problem:

1. What are four 135 MW units (what the produce)?

2. What are the suction and delivery pipe sizes? The valve size given 300 mm appears to be too small to handle 15600 m3/hr water.

3. Water pressure at both suction & discharge.

4. What are 5 vertical lines on right side? What are line sizes?

5. Which is pump 8? Where are the fibre filters located?

6. Type of valves (either of gate/globe/butterfly/plug/diaphragm...)