GENERALPIPINGREQUIREMENTS:

Designing and erecting an efficient piping system requires certain aspects/ requirements which could be found in our PME handbook…

1. ALL PIPING SHOULD RUN PARALLEL TO THE BUILDING WALLS.

-- If such piping consideration is not considered, the lay-out of pipes would be like a “MAZE” which would complicate line tracing (more so if no color coding exists) as well as repairs and alterations…. With space limitations (as in the case of ship vessels0) such type of pipe laying could no longer be prevented….

2. GROUPED PIPING SHALL BE SUPPORTED ON RACKS EITHER ON HORIZONTAL OR VERTICAL PLANES.

EXAMPLES OF PIPE SUPPORTS (RIGID):

EXAMPLES OF PIPE SUPPORTS (FLEXIBLE):

LISTING OF PIPE SUPPORTS:

3. ALL PIPING TO HEADERS SHALL COME FROM BELOW RACK.

4. ALL PIPING FROM HEADERS SHALL GO UP ABOVE RACK.

5.ALL PIPING ABOVE OR BELOW RACKS SHALL BE SUPPORTED ON SEPARATE RACKS. Separate rack for pipes located at different elevations

6.ALL PIPING SHOULD RUN WITH SLIGHT INCLINATION.

7. ALL PIPING ON RACKS SHALL HAVE A SUFFICIENT SPACING. With the right spacing, repairs/ alterations could be done in a jiffy as well as maximizing space limitations Although maze like in appearance, there are still workable spaces for repairs/ alterations

Pipes layed without proper spaces would be next to impossible to be repaired/ altered unless the whole piping system is disassembled. --Pipes layed without proper spaces would be next to impossible to be repaired/ altered unless the whole piping system is disassembled.

8. ALL PIPING 63.5MM (6.35CM) AND ABOVE SHALL BE FLANGED WHILE SMALLER ONES CAN BE SCREWED. Flanged connections Screwed connections

9. ON LONG HEADERS, A PAIR OF FLANGES SHALL BE PROVIDED FOR EVERY THREE- LENGTHS OF 6000MM OF PIPES 63.5MM AND ABOVE.

10. ON LONG HEADERS, A PAIR OF UNIONS SHALL BE PROVIDED FOR EVERY THREE- LENGTHS OF 6000MM OF PIPES SMALLER THAN 63.5MM. UNIONS PLUGS

THREADED PIPE CONNECTORS COUPLING NIPPLE UNION

11. ALL PIPING SUBJECTED TO VARYING TEMPERATURES SHALL BE PROVIDED WITH EXPANSION JOINTS OR EXPANSION LOOPS certain sections prone to thermal expansion are fixed rigidly with respect to a given foundation/ support it would likely develop THERMAL STRESS which could be a reason for failure EXPANSION JOINTS

12.NO GALVANIZED PIPING SHALL BE USED FOR STEAM APPLICATIONS.

13.NO PIPING MATERIAL SHALL BE USED THAT IS EASILY CORRODED BY MATERIAL PASSING THRU. THERMOPLASTIC PIPES/ VALVES/ FITTINGS

14. ALL PIPING SHALL BE CLAMPED BY “U- BOLTS” OR CLAMPS TO SUPPORTING RACKS EXCEPT STEAM PIPING. ALL STEAM PIPING SHALL BE SUPPORTED ON ROLLERS OR SLIDING SUPPORT. U-BOLT ROLLERS

15. PIPING SUPPORTS SHOULD BE PLACED ON A 3000MM INTERVAL OR LESS.

16. ALL PIPING CARRYING PRESSURE SHALL BE OF SUFFICIENT BURSTING STRENGTH FOR THE PRESSURE APPLIED. A MINIMUM FACTOR OF SAFETY OF 4 FOR WORKING PRESSURE APPLIED SHALL BE USED.

17. FOR CONVEYING LIQUIDS SUBJECT TO WATER HAMMER, ADDITIONAL FACTOR OF SAFETY OF 100% OF THE WORKING PRESSURE SHALL BE APPLIED. WATER HAMMER ARRESTER/ ATTENUATOR

WATER HAMMER is a phenomena that is characterized by vibration and distinct sounds within pipes when the valve controlling the fluid flow is suddenly stopped. For fluid to flow it requires force/ pressure. Once the flow is impeded, the flow crashes at the “wall” of the valve. This sends shockwaves chracterized by vibration and distinct sounds.

The end result is catastrophic depending upon the volume flow rate of fluid as well as the pipe diameter. Damaged brought about by water hammer in a hydraulic power plant. From top left; Ruptured valves to a damaged pipeline (top right and bottom)

18. ALL PIPING CARRYING STEAM, HOT WATER, OR HOT LIQUIDS SHALL BE PROPERLY INSULATED.

19. DRAINS FROM STEAM PIPING SHALL BE PROVIDED WITH STEAM TRAPS. STEAM TRAPS STEAM DRAIN

20. ON ALL SCREWED JOINTS, THE THREADED PORTION SHALL ENTER FITTINGS WITH THREE THREADS BY HAND BEFORE A PIPE WRENCH IS TO BE USED.

21. PIPE THREADS SHOULD BE LUBRICATED BY WHITE LEAD, RED LEAD, GRAPHITE, AND OIL OR OTHER APPROVED THREAD LUBRICANTS BEFORE TIGHTENING.

22. NO RUBBER OR RUBBERIZED GASKETS SHALL BE USED FOR STEAM OR OTHER HOT LIQUIDS.

23. A SHUT-OFF VALVE SHALL BE INSTALLED ON EVERY BRANCH FROM HEADERS.

24. ALL PIPING SHALL BE REASONABLY BE CLEANED BEFORE INSTALLATION.

25. ALL PIPING SHALL BE FREE FROM BURRS OR PROTRUDING METALS INSIDE.

26. NO PIPING SHALL BE IMBEDDED IN CONCRETE WALLS OR FLOORS.

27. WHERE PIPING HAS TO BE LOCATED IN TRENCHES, THE PIPES SHALL BE SUPPORTED ON STEEL BRANCHES ON FLOOR OF TRENCH.

28. WHERE PIPING HAS TO BE LOCATED IN TRENCHES, A SUITABLE DRAINAGE OR SUMP FOR REMOVAL OF LIQUID ACCUMULATIONS SHALL BE PROVIDED FOR TRENCH.

29. WHERE PIPING CARRYING STEAM OR HOT LIQUIDS HAVE TO PASS WALLS OF CONCRETE SUITABLE SLEEVES MADE OF PIPES ONE SIZE BIGGER SHALL BE IMBEDDED IN CONCRETE BEFORE THE PIPE IS LAID.

30. PIPING TO ALL EQUIPMENT SHALL NOT BE SUBJECTED TO ANY STRESS ON EQUIPMENT BEING CONNECTED.

31. PIPES CARRYING LIQUIDS WITH SOLIDS SHALL USE LONG RADIUS ELBOWS OR TEES WITH PLUGS IN THE DIRECTION OF FLOW.