Read about START-PROF pipe stress analysis software
Single Use Compensators enable pre-stretching of buried pipelines. Pre-stretching involves heating the pipeline to half the temperature range in operating mode. After activating single use compensators and welding restraint edges, the pipeline becomes a continuous structure. These expansion joints are used only once. Ideal for long straight pipeline sections where thermal expansion is accommodated through axial compression/tension of pipe material.
Start-Elements provides approximate modeling of single use compensator spacing and locking temperature.
Start-Elements ignores thrust forces; START-PROF includes them.
Start-Elements ignores pressure deformation; START-PROF includes it.
Start-Elements ignores flexibility; START-PROF includes it.
Start-Elements ignores fatigue failure; START-PROF includes it.
Start-Elements ignores bending moments from weight loads; START-PROF includes them.
START-PROF provides more accurate analysis than Start-Elements. Use Start-Elements for preliminary analysis only. Perform final safety verification with START-PROF.
If single use compensator conditions are not met, error message "Single Use Compensators cannot be inserted. Temperature difference is too high" displays when:
Sr<2*Sa,
where
Sr - stress range from hot to cold temperature difference,
Sa - allowable stress. For CJJ/T 81-2013 code Sa = min(3*Sh, Ss),
Sh - allowable hot stress,
Ss - allowable local wall stability stress per EN 13941 p.7.4.2.4.
If error occurs - increase wall thickness to raise Ss value or select higher strength steel with greater Sh value.
Copy input data using 
toolbar
icon and paste into other Start-Elements analyses using 
toolbar icon.
Property |
Description |
External diameter, D |
Pipe outside diameter |
Pipe wall thickness, S |
Nominal wall thickness |
External casing diameter, Dc |
Insulation jacket outside diameter. Set to 0 if no insulation. |
Cold temperature |
Average pipe wall temperature after cooling. |
Operation temperature |
Operating temperature in operating condition. More... |
Depth, Z |
Depth from ground surface to pipe centerline. |
Uniform pipe weight |
Pipe and attached equipment weight per unit length. More... |
Uniform insulation weight |
Insulation weight per unit length. More... |
Uniform product weight |
Fluid content weight per unit length. More... |
Backfill soil number |
Trench soil type from soil database (see appendix 1 below) |
Operation pressure, P |
Operating pressure in operating condition. Required for all standards except SNIP 2.05.06-85. More... |
Steel grade |
Pipe material from materials database |
Weld pressure quality factor |
Set per applicable standards.
Calculate automatically
using |
Insulation type |
Insulation type: Armopenobeton, polymer, polyurethane, other. |
Analysis results include:
Property |
Description |
Spacing Lmax |
Maximum spacing between single use compensators based on strength criteria. |
Locking temperature |
Temperature for expansion joint activation. |
Expansion joints > Single use. Analysis of Lmax and Locking Temperature
.