Natural Gas Pipeline ASME Anchor Forgings or Flanges
Application
The ANCHOR FLANGE is designed for immobilization of high-pressure pipelines. Normally, it is a relatively simple matter to compensate for the expansive movement of the pipe caused by temperature changes and internal pressure.
Where Are They Used
The designer calculates the amount of expansion (or contraction) to be expected and then provides expansion elements such as loops, offsets, bends, etc., to give the line suf?cient ?exibility to absorb the stresses that are created. In conjunction with this, there must be a suitable number of anchors installed to ensure proper functioning of the expansion element. But at pipeline river crossings, compressor stations, meter, and valve settings, etc., the problem is complicated by the magnitude of the end forces resulting from the use of large diameter pipe (a 30" O.D. x .500 wall pipe subjected to a 90° F temperature change and an operating pressure of 1000 psi will develop an end thrust of over 1,000,000 pounds, and the dif?culty of providing adequate anchorage. Anchor Flanges can address these problems.
Custom Design
Anchor Flanges are custom designed to provide the most economical dimensions for each special application. Stress calculations are performed as outlined in ASME Section VIII, Division I, Appendix 2. Shown in Figure 1, as an example, are typical dimensions for an Anchor Flange designed to match a 24" O.D. x .500 wall, API 5LX60 pipe, Type “B” construction, 1480 psi with a temperature differential of 90°F, and a maximum concrete bearing stress of 1500 psi.
Information Needed To Quote
In order to reply promptly to inquiries and to propose the most economical design for speci?c service conditions, the following information is needed:
1. Matching pipe O.D., wall thickness, minimum yield, material spec.
2. Design Pressure
3. Temperature Differential
4. Design Code (ASME, B31.4 or B31.8)
5. Design factor (if applicable)
6. Design concrete bearing stress (if not speci?ed, 1500 psi will be used)
7. Special requirements (NDE, Charpy tests, unusual loads, etc.)
