Air Cooled Heat Exchanger

Learn more about START-PROF pipe stress analysis software

Analysis results appear in the Loads on Nozzles and Equipment Table. See also How to Reduce Nozzle Loads in START-PROF

Properties

 

Property

Description

Name

Element identifier. When checked, displays in 3D view.

Auto calculation of nozzle temperature movements

Calculates nozzle movements automatically using ΔX=L/2·α·(T-Ta), ΔY=DY·α·(T-Ta), ΔZ=DZ·α·(T-Ta), where α is the thermal expansion coefficient from material properties, T is equipment temperature, Ta is ambient temperature, L is tube length, and DY, DZ are distances from floating header center. When disabled, specify movements manually.

Material of Heat Exchanger

Material selection from the materials database.

Manufacturing technology

For ASME B31.1, ASME B31.3, DL/T 5366-2014, seamless pipe always uses Wl=1.0. Electric-welded pipe Wl comes from the database. More...

When using GOST 32388-2013, pipe properties are sourced from different materials databases based on pipe type (seamless or welded).

Temperature of Heat Exchanger

Heat exchanger operating temperature. More...

This property is modifiable per operation mode. Click to view values across all operating modes.

Factor for Nozzle Allowables

Default: 1.0. Adjust per manufacturer specifications. Multiplies nozzle allowable loads from Table 4.

Factor for Floating Header Allowables

Default: 1.0. Adjust per manufacturer specifications. Multiplies floating header allowable loads per section 7.1.10.2.

Factor for Whole Heat Exchanger Allowables

Default: 3.0. Adjust per manufacturer specifications. Multiplies whole heat exchanger allowable loads per section 7.1.10.3.

Axis of Heat Exchanger

X-axis orientation along tube direction per drawing:

Tube Length

Tube length L used for axial thermal expansion calculation: ΔX=α(Tope-Tambient)L/2

Remove restraints for hanger selection

When enabled, removes specified restraints during weight case for spring hanger selection. Restraints remain active during main analysis. This technique isolates weight loading from nozzle elements, allowing springs to carry load at zero displacement under pure weight.

  • Remove vertical restraint: Releases only vertical restraint during spring selection

  • Remove custom restraints: Manually select restraints to release during spring selection

  • Remove all restraints: Releases all directional restraints during spring selection

Floating Header

Assign node numbers connected to floating header. Click "Add" for additional headers.

Allowable Loads

Available options:

  • No check: Nozzle loads are not verified

  • Manually: Specify six allowable loads per nozzle (equivalent to Table 4) and six per floating header (equivalent to 7.1.10.2)

  • By API 661/ISO 13706: Currently unavailable - under development

Air Cooled Heat Exchanger Nozzles at Pipe End Nodes

When nozzles are located at pipe end nodes, START-PROF automatically models thermal expansion along X, Y, and Z axes.

All nozzles are modeled using fixed anchors.

Modeling with Rigid Elements

When the exchanger body is modeled using rigid elements, thermal expansion is simulated through rigid element expansion.

Nozzle Load Verification

Nozzle loads are compared against Table 4 allowable values.

Floating header load sums are verified against section 7.1.10.2 criteria.

Total loads from all floating headers are checked against section 7.1.10.2 values multiplied by 3.

Menu and Toolbar Access

To insert an air cooler: Select the target node, then choose Insert > Equipment > Air Cooler Nozzle API 661/ISO 13706