August 2010 - Pipe Supporting Systems

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At last we are back in Canada after another trip 'Down Under' last month. I taught on piping course in Perth and one in Brisbane. Exhausting but very enjoyable. Australia certainly has a lot to offer.


This months’ tip

Pipe Supporting Systems

Piping is supported either from above by the use of hangers or from below by resting supports. When routing piping indoors, run the piping close to structural steel in order to attach the pipe support steel to it.

When piping is run outdoors in groups, as in the case of a refinery, or chemical plant, it is usually supported on a piperack. If run individually there are a number of standard support designs that are in common use.

REMEMBER: Keep the support as simple as possible and if using spring hangers, make sure they are accessible.

In the majority of industrial jobs, pipe supports are designed and fabricated by the engineer, however, most supports are also available commercially from a pipe support supplier such as Anvil, Lisega, AAA etc.
The design of pipe supports is covered in the various piping codes. Below is an excerpt from B31.1, note the reference to MSS SP-58 which is the standard covering ‘Pipe Hangers and Supports - Materials, Design and Manufacture’.

121 DESIGN OF PIPE SUPPORTING ELEMENTS (ASME B31.1 Power Piping Code)
121.1 General
“Design of standard pipe supporting elements shall be in accordance with the rules of MSS SP-58. Allowable stress values and other design criteria shall be in accordance with this paragraph. Supporting elements shall be capable of carrying the sum of all concurrently acting loads as listed in para. 120. They shall be designed to provide the required supporting effort and allow pipeline movement with thermal changes without causing overstress. The design shall also prevent complete release of the piping load in the event of spring failure or misalignment. All parts of the supporting equipment shall be fabricated and assembled so that they will not be disengaged by movement of the supported piping. The maximum safe loads for bolts, threaded hanger rods, and all other threaded members shall be based on the root area of the threads.”


Pipe supports must be designed to perform a number of functions:

  1. To carry the weight of the piping filled with contents and any insulation plus additional loads – wind, snow, ice, etc.
  2. To cater to expansion and contraction loads, seismic loads, vibration loads etc.
  3. To allow for drainage of the pipe. If the line is sloping then ensure that the pipe sag between supports is not greater than the pipe slope.