Air Cooled Heat Exchanger

Read about START-PROF pipe stress analysis software

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

Properties

 

Property

Description

Name

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

Auto calculation of nozzle temperature movements

Automatically calculate the nozzle movements as L/2*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, L - tube length, DY, DZ are distanced from the floating header center. If checkbox is not checked, then nozzle movements can be specified manually

Material of Heat Exchanger

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).

Temperature of Heat Exchanger

Heat exchanger 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 Nozzle Allowables

The Default value is 1.0. You can change this value according to heat exchanger manufacturer instructions. Nozzle allowable loads in table 4 are multiplied by this factor

Factor for Floating Header Allowables

Default value is 1.0. You can change this value according to heat exchanger manufacturer instructions. Floating Header allowable loads in 7.1.10.2 are multiplied by this factor

Factor for whole Heat Exchanger  Allowables

Default value is 3.0. You can change this value according to heat exchanger manufacturer instructions. Whole heat exchanger allowable loads in 7.1.10.2 are multiplied by this factor according to 7.1.10.3

Axis of Heat Exchanger

X-axis direction according to drawing (along tubes direction):

Tube Length

The length of tubes L. It is used for calculation of axial thermal expansion of heat exchanger using equation ΔX=α(Tope-Tambient)L/2

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

Floating Header

Set the node numbers to which one floating header is connected to. To add more floating headers click "Add"

Allowable Loads

There are a several options:

  • No check. Loads on the nozzle are not checked

  • Manually. User should specify six allowable loads for each nozzle (analog of table 4) and six allowable loads for each floating header (analog of 7.1.10.2)

  • By API 661/ISO 13706. This option is unavailable at this moment. It is under development and become available soon.

Air Cooled Heat Exchanger Nozzles in Pipe End Nodes

If air cooled heat exchanger nozzles are placed in the pipe end nodes, START-PROF automatically model the thermal expansion of all nozzles by X,Y,Z axes.

All nozzles are modeled using fixed anchors.

Air Cooled Heat Exchanger Modelling using Rigid Elements

if air cooled heat exchanger body is modeled using rigid elements, then thermal expansion are modeled as thermal expansion of rigid elements.

Check Air Cooled Heat Exchanger Nozzle Loads

For each nozzle the loads are compared with values from table 4

The sum of nozzle loads on each floating header is compared with values from 7.1.10.2

The sum of loads from all floating headers is compared with values from 7.1.10.2 multiplied by 3

Menu and Toolbar Access

To insert a pump, select the desired node and use the menu option: Insert > Equipment > Air Cooler Nozzle API 661/ISO 13706