Read about START-PROF pipe stress analysis software

Compressor API 617

This element allows to model the compressors and check the loads according to API 617 standard. One "Compressor" object can be connected to 2-4 nodes. Allowable loads are checked for each individual nozzle and for whole compressor. Analysis results can be found in Loads on Nozzles and Equipment Table. See also "How to Reduce the Nozzle Loads in START-PROF"

There can be two options of using compressor element:

1. Put Compressor nozzles into the pipe end nodes. In this case, the compressor nozzles are automatically modeled as a fixed anchors. Compressor temperature expansions are automatically modeled as anchor movements.

2. Put Compressor nozzles into intermediate nodes. In this case user should create the compressor model using rigid elements, cylindrical shells, and other elements. Temperature expansion are modeled as temperature expansions of elements, that model the compressor (rigid elements, pipes etc.)






Element name. If checked then it shown in 3D view

Auto calculation of nozzle temperature movements

Automatically calculate the nozzle movements as DX*Alpha*(T-Ta), DY*Alpha*(T-Ta), DZ*Alpha*(T-Ta), where Alpha is thermal expansion factor (taken from selected material properties), T is equipment temperature, Ta is ambient temperature, DX, DY, DZ are distances from compressor center. If checkbox is not checked, then nozzle movements can be specified manually


Material from materials database

Manufacturing technology

For ASME B31.1, ASME B31.3, DL/T 5366-2014 seamless pipe will always use Wl=1.0. For electric-welded pipe Wl will be specified from database. More...

When using  GOST 32388-2013, pipe physical properties are taken from different materials databases depending on pipe type (seamless/welded).


Compressor Temperature. More...

This property can be changed in different operation modes. To see the value of this property in all operating modes push the button

Factor for Allowable Loads

The default value is 1.0. Allowable values are 0.5-20.0. You can change this value according to compressor manufacturer instructions. The allowable loads De and Dc will be multiplied by this value.

Fshaft Direction

Fshaft X-axis direction according to following drawings:

Compressor Center Point Offsets

The node, and offsets from this node to the compressor centre (point 3 on the drawings above)

Remove restraints for hanger selection

If this option is activated, then some restraints are removed from nozzle element during weight run of variable and constant spring selection. During main analysis restraints are working. This trick allows to remove the weight part of loading from the nozzle element. Springs will take the exact load, at which displacements from pure weight load is zero. Options:

  • Remove vertical restraint. Only vertical restraint will be released during hanger selection

  • Remove custom restraints. You should manually choose which restraints should be released during hanger selection

  • Remove all restraints. During hanger selection all direction restraints will be released

Suction Nozzle

Discharge Nozzle

Additional Nozzle 1

Additional Nozzle 2

Set the node number to which nozzles are connected to. If other side piping model is absent, you can specify the loads manually, just select "Set Custom Loads"

Check Allowable Loads for Compressor

According to API 617 standard the load on each nozzle of compressor shouldn't exceed

Sum of loads of whole compressor shouldn't exceed

Menu and Toolbar Access

To insert a compressor, select the desired nodes and use the menu option: Insert > Equipment > Compressor API 617/619