BOILER HANGERS

The selection criterion is load variation sensitivity. The support force of a spring hanger changes as the pipe moves — typically about 25% of the hot load over the full travel range. This is acceptable for most economizer, convection tube and process steam piping locations where nozzle loads are not critical.

A constant support hanger is required when load variation cannot be tolerated — mainly at pressure vessel nozzle connections such as steam drums and superheater headers, turbine inlets and any location where pipe stress analysis shows that spring-generated variation exceeds the allowable nozzle load. Pipe stress analysis software such as Caesar II or ROHR2 will identify these locations. If you have a stress isometric or BOM, send it to us and we will confirm the hanger type selection for each support point.

Hot load is the support force required when the pipe is at operating temperature and pressure — this is the design load from pipe stress analysis and is the load the hanger must deliver in service.

Cold load is the hanger setting at ambient temperature before hydrostatic testing and start-up. Because the pipe moves from the cold position to the hot position during start-up, the spring is preset to a position that delivers the correct hot load once the pipe reaches its operating position. We set each hanger to the cold-load position before delivery and provide a setting sheet confirming the cold indicator position. Installers lock the hanger travel during construction and release the lock before start-up.

The fastest way to quote is to provide a pipe hanger bill of materials (BOM) from the pipe stress engineer or boiler OEM. A typical BOM lists each support point with hanger type (spring / constant / rigid), hot load in kg or lb, travel range in mm, pipe operating temperature and applicable design standard.

If the BOM is not available yet, we can prepare a preliminary estimate based on boiler type and steam capacity, the approximate number and location of support points, operating temperature and pressure of the steam lines, and the applicable design code such as ASME B31.1, GB or EN.

The standard documentation package for each unit includes the EN 10204 3.1 material test certificate for structural steel components, load test report with actual load-versus-deflection curve, dimensional inspection record, installation setting sheet showing cold indicator position and hot load, and packing list linked to hanger BOM tag numbers.

For projects with a formal QCP/ITP, we can define hold points and witness points for material verification, assembly inspection and load test acceptance. All documents are traceable to individual serial numbers for each unit.

Yes. For replacement units, we need the nameplate information of the existing hanger — usually stamped on the casing or attached tag — including hanger type designation, hot load, travel range and spring rate. If the nameplate is not readable, we can manufacture according to on-site measurements and pipe operating conditions. Replacement hangers are preset to the same cold setting as the original units, so no recalibration is required during the outage. We can also manufacture to match proprietary designs from other hanger manufacturers if dimensions and performance data are provided.

Yes. ORL Power supplies complete boiler pressure part packages — superheaters, reheaters, economizers, steam drums, headers and water walls — and can include the hanger system in the same order. All components can be shipped together in the same container, reducing freight cost and customs procedures. One QC team covers inspection of the complete package, and one document file covers all pressure parts and hangers for the project. This is the standard arrangement for EPC contractors requesting a complete boiler island from a single source.