This specification covers the requirements for the design, fabrication and use of our pre-insulated low temperature pipe supports. These supports are for pipes having surface temperature ranges of 40°F (4.4°C) to 1800°F (982°C).
- All insulated pipes shall be supported with pre-insulated pipe supports.
- Pre-Insulated pipe supports shall comply with the following standards:
A. ANSI/ASME B31.1 & B31.3
B. Manufacturers Standardization Society SP-58, 69, & 89.
- The following criteria shall be considered in the selection of high temperature pre-insulated pipe supports:
A. Vertical, lateral and axial support design load limits.
B. Vertical, lateral, and axial support design travel limits.
C. Temperature of the support, at the pipe surface, and ambient conditions.
D. All test or pre-operational loads that may exceed normal operating conditions.
E. Any dimensional clearances needed during installation and operation should be specified.
F. Material for any items that will be welded directly to the pipe.
G. All loading and displacements caused by seismic, hydraulic surge, or other disturbances.
H. Temperature at the support steel.
- Upon request by the purchaser or the end user, design calculations of supports will be made available for review.
- Upon request by the purchaser or the end user, localized stress calculations for lugs and other welded attachments will be made available for review.
- Prior to placing an order, all special requirements such as mill test reports, material certification or non-standard materials must be specified.
- The load bearing insulating materials used in the pre-insulated pipe support shall be the same material that was used to rate the support.
- At the request of the end user or the purchaser, we will make available compressive strength and thermal conductivity testing results of the high density Calcium Silicate insulationin the format provided by MSS SP-89. Testing will be done at the maximum temperature of 1200.
- A description of the magnitude of load that can be applied to the support shall be provided for evaluation upon request. A minimum safety factor of 3 at the system design temperature shall be used to determine the maximum load.
- Testing for compressive strength properties shall comply with ASTM D1621, the standard testing method, for compressive properties of Rigid Cellular Insulation.
- Testing for thermal conductivity shall comply with ASTM C165, Standard Test Method of Measuring Compressive Properties for Thermal Insulation.
- Load bearing element capacity shall be demonstrated at the system design temperature and load.
- The pre-insulated pipe support assembly shall exert enough clamping force to assure that the support will move axially with the pipe and will not slip when under design conditions.
- All slide plate surfaces shall be designed so that the coefficient of friction will be limited to .1 for the design life without requiring lubrication. Any friction reducing material that requires bonding shall be bonded to a backing structure prior to shipment.
- The lower design temperature of the unit at the pipe surface shall be 40°F (4.4°C). The maximum outside design temperature should be 140°F (60°C), the maximum pipe surface temperature should be 1800°F (982°C). For higher or lower temperatures, please contact us.
- The required properties of the load bearing insulating materials under design conditions are:
A. The maximum thermal conductivity is 0.77 BTU-in/hr-ft2 – °F at a mean insulation temperature of 700°F.
B. There can be a maximum of 1/32″ of non-permanent deformation under the pipe due to permanent consolidation of the load bearing insulation.
C. There can be an additional 1/32″ of non-permanent deformation under the pipe.
- The outside surface temperature of the unit shall not exceed 120°F when ambient air is 140°F at all ambient temperatures.
- The pre-insulated pipe support shall:
A. Come pre-assembled with sufficient insulation flushed to the outer metal jacket, allowing the pipe insulator to butt the line insulation against it.
B. Will withstand the clamping forces transferred by the cradle.
C. Will be treated to prevent moisture degradation in accordance with ASTM C656 Type I.
D. The ID and OD dimensions of the insulation shall conform to ASTM specification C585 unless otherwise specified.
- Designs having sliding surfaces shall incorporate a stainless steel sheet metal sliding surface on the underside of the support base, over a factory mounted and mechanically attached polyethylene slide pad on a carbon steel mounting plate which is welded or bolted to the support steel. Teflon slide padsare optional and may be used to replace the polyethylene pads.
- All welding shall comply with B31.3 and B31.1 Piping Code and AWS D1.1
- The following items unless otherwise noted on contract drawings shall be in accordance with the following:
A. Structure shapes and plate: ASTM A-36
B. Bolts and studs: ASTM A-307
C. Nuts: A563