Supporting of Piping Systems: Few Guidelines

The piping system is a major part of any hydrocarbon industry. Pipes as irregular space frames are usually not self-supporting. Hence, they must be supported. Proper pipe support knowledge during the layout stage is advantageous. Piping Loads generated due to Weight, Pressure, Temperature or Occasional Event has to be transmitted from pipe to supporting structures with the help of appropriate pipe supports.

Why Piping supports are necessary ?:

Pipe Supports are required to prevent…..

  • Pipe stresses in excess to code allowable limits.
  • Leakages in flanged joints etc.
  • Excessive Line Vibrations.
  • Undesirable effects of Seismic loading.
  • Unintentional disengagement (lift off) of piping from its supports.
  • Excessive pipe sag (Normally more than 10 mm for process piping and 2.5 mm for power piping).
  • Exposure of elements to temperature extremes, outside their design limit.
  • Undesirable line movements to protect sensitive equipment against overloading.
  • Excessive loading in support itself
  • To limit the thermal expansion

Codes and Standards for piping supports:

The following codes and standards are used for piping support design.

  • MSS-SP-58- Establishes the material, design, and inspection criteria to be used in the manufacturing of standard pipe supports. (USA)
  • MSS-SP-69- Provides recommendations for the selection and application of pipe supports. (USA)
  • MSS-SP-89- Provides recommendations for the fabrication and installation of pipe supports. (USA)
  • BS-3974- Specification of pipe supports 1, 2, 3. (UK)
  • VGB-R-510 L- Standard supports guidelines. (Germany)
  • RCC-M- Specifications for pipe supports. (France)
  • MITI 501- Technical regulations (Japan)

Design and selection of piping supports

The complex requirement of today’s piping support elements is reliable functioning, maintenance-free operation, economic and easy installations, quick delivery of components and low unit prices.

Major Criteria governing support hardware are Support function, Magnitude of expected load, space limitations, design temp of the piping system, expansion effects of piping systems, piping attachment and supporting structure material compatibility, piping insulation, suitability to the environment, ease of operation, inspection and installation.

Layout considerations for Piping Supports

The following points need to be followed for optimized pipe supporting.

  • Group pipelines so as to minimize the number of structures needed solely to pipe supports.
  • Route lines close to the possible point of supports ( i.e. grade or structure which is provided for other purposes.)
  • Supports or braces to be located at or near neutral pts. (thermal null pts)
  • Supports to be located as near as possible to concentrated loads such as valves, flanges, heavy actuators, etc.
  • Piping susceptible to vibration such as compressor connected lines to be supported independently. The use of hold down or similar supports offering resistance to motion and providing some damping capacity to be used rather than hanging type supports.
  • Piping connected to the top of the vessel to be advantageously supported from the vessel to minimize relative movement between supports and piping.
  • Always maintain the distance between supports as per project specification recommended support span table. ( it is applicable to straight run pipe length only.) When a change of direction in a horizontal plane occurs, it is suggested that the spacing be limited to ¾ times the standard pipe span.
  • Sufficient space to be provided to facilitate support assembly installation, inspection, and maintenance.
Piping Supports
Figure Showing Piping Supports

General piping support terminologies and basic function

  • Restraint- Any device that prevents, resists, or limits the free thermal movement of piping.
  • Brace- A device primarily intended to resist displacement of piping due to forces other than thermal expansion and gravity.
  • Anchor- A rigid restraint providing substantially full fixation.
  • Stop- A device that permits rotation but prevents translatory movements of piping.
  • Guide- A device which prevents the rotation about one or more axis.
  • Hold Down Support- A device that holds the pipe in position disallowing vertical upwards movement or allows decided upward movement.
  • Hanger- A support by which piping is suspended from a structure that functions by carrying the piping load in tension.
  • Resilient support- A support that includes one or more largely elastic members to carry pipe sustain + thermal loads at the same time allowing pipe thermal movement in the desired direction.
  • Sliding support- A device that is provided below piping to take gravity loads, offering no resistance other than frictional to horizontal motion.
  • Rigid support- A support providing stiffness in at least one direction.
  • Damping element- A device which increases damping of a system offering high resistance against rapid displacement, caused by dynamic loading while permitting essentially free movement.

Types of Piping Supports

The following types of supports are most popular in oil and gas, petrochemical industry.

  • Hanger Supports – 1) Variable Hanger 2) Constant Hanger 3) Rigid Hanger.
  • Dynamically Loaded Supports – 1) Struts 2) Snubbers 3) Sway Brace 4) Energy absorbers 5) Pipe Clamps 6) Pipe whip / Hold down restraints.
  • Pipe Bearing Components – 1) Pipe Saddle 2) Pipe Shoe 3) Pipe Trunnion 4) Wear Pad.
  • Threaded Members – 1) welding nut 2) welded beam attachment 3) Clevis 4) Turnbuckle 5) Tie rod 6) Stud bolt, nut, locknut, spring washers, etc.
  • Slide Bearing Plates – Teflon, Stainless steel, graphite.
  • Pipe Supports for Cold Service.
  • Depending on Support Position-Primary Support and Secondary Support

Famous Pipe Support Manufacturers

The number of Piping Support manufacturers is quite long. However, the following are the most popular:

  • Piping Technology and Products Ltd.
  • Carpenter and Paterson Ltd.
  • Lisega Ltd.
  • Binder Group Ltd.
  • Pipe Support Group Ltd.
  • Sarathi Engg Ent Pvt Ltd.
  • Anvil Group etc to name a few

Support Engineering

Minimum Data required to start supporting

  1. Piping GAD
  2. Electrical and Inst cable trench/trays layouts
  3. Civil and Structural drawings
  4. Piping spec and line list
  5. Insulation spec
  6. Valve’s weights
  7. Equipment connection displacements
  8. Stress recommendations (Stress isometrics) and Support loads.

Pipe Support Span

Typically piping is supported at regular intervals on steel supports embedded in concrete foundation or directly on the steel structure. The distance between supports is the supporting span.

Basis for calculation of Maximum support span

There are three main factors that affect the support span.

  • Stress
  • Deflection/ sagging and
  • Frequency of piping system (for two-phase flow lines, reciprocating equipment connected lines, vibrating lines, etc.)

Guidelines for Typical Piping System

Supporting of Stress Critical Lines

  • Criteria for critical lines
  • Support location by Designers
  • Support type by stress engineer
  • Primary attachments and secondary supports by designers
  • Line stop/Guide gaps to be taken care

Supporting of non-critical lines

  •  Senior designer to decide support type
  •  Support span
  •  Guide span
  •  Concentrated loads e.g. valves, inst
  •   Long piping leg, stress engineer to be consulted

Supporting of Insulated Pipes

  •  No direct resting, pipe shoe to be provided
  • Min. clearance between the insulation and the supporting structure shall be at least 50 mm.

Supporting of Non- Insulated Pipes

Directly rested except following

  • Pipes with sizes larger than DN 600
  • CS pipes with less than SCH 20
  • SS pipes with less than SCH 10S
  • The pipe that requires a slope
  • Dissimilar material to avoid galvanic corrosion
  • Pipe to be supported on pipe shoe to avoid damaging to the pipe wall

Vertical pipes

  •   Standard span chart does not apply
  •   Supports to be located on the upper half  of the portion (i.e. above C.G. of pipe)
  •   Vertical guide spacing
  •   Clamped supports with weld-on shear  lugs to   avoid the pipe slipping under the clamp

Few more Resources for You…

Purpose of Pipe Supports
An article on Piping Support span
Supporting of Dual Insulated Piping System
Dynamic Restraints
Piping Stress Analysis

Anup Kumar Dey

I am a Mechanical Engineer turned into a Piping Engineer. Currently, I work in a reputed MNC as a Senior Piping Stress Engineer. I am very much passionate about blogging and always tried to do unique things. This website is my first venture into the world of blogging with the aim of connecting with other piping engineers around the world.

6 thoughts on “Supporting of Piping Systems: Few Guidelines

  1. It’s a great article with proper explanation.Thanks a ton for  this wonderful information. Sir, I have a request if you can provide an article on example of dummy piperack analysis in CAESAR-II with selection of shoe type supports and where to place those supports in addition where to place expansion loops, it will be so grateful of you.

  2. Wow, I had no idea that there was so much to know about industrial piping systems. Although, it does make sense that you would need to find a way to support them. After all, by using things like hangars and pipe bearing components you can keep the pipes from crashing down on your heads.

  3. Something to always check when installing pipe supports: (a) Check that the additional lines installed on the beams have not deflected the beams so that the other lines are still adequately supported.(b) Ensure that the lines during commissioning have not locked up the other lines and preventing them to move.(c) Ensure that the line have clearance necessary to absorb any movement.

    There are so many considerations to take into account when commissioning a plant piping.
    If in doubt call an experienced piping engineer out to check and verify your observations.

  4. Very useful Information,

    I have met with a problem where we have provided 800 DN CHW pipe without saddle plate in our support design ,

    Can anyone please provide any reference to the codes or standards which support or reject this design,

    does any code says anything about necessity of saddle?

    1. Hi 1. Here that location required pipe shoes not only saddle?
      2. Is it that location is simple rest or semi anchoring?
      See if it is simple rest… provide a clamped shoe or welded shoe.
      If u r not providing a shoe. Then u have to check pipe intendation check on that location to proceed.
      Because line contact is not allowed such big bore. Wall thickness also played important role.

      1. Thank you for reply, that location was simple rest,, so clamped shoe will be more suitable I think,,,

        How to perform intendation check?

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