Heat Exchanger Tube Rupture Data Requirements

The following data is required in order to undertake a detailed unsteady analysis of the effect of ruptured tube in a heat exchanger system. The data which is relatively easy to assume has been marked with an asterisk (*).

Drawings

• Process and Instrumentation Diagrams.
• Isometric drawings detailing pipe lengths and elevations for all pipework.
• Flow Utility diagrams (if available).

Pipework

• Internal diameters.
• Wall thicknesses.
• Pipe wall material type and its pressure rating, particularly any ability to accept negative pressures.

Heat Exchangers

• Number of tubes, layout and dimensions.
• Heat exchanger end box dimensions.
• Pressure loss at duty flow rate, both shell and tube sides.
• Type and control mechanism for trim valves.
• Operating pressures in the shell and tube sides of the heat exchanger.
• Details of the fluid on both tube and shell sides of the heat exchanger.
• Estimation of the maximum number of tubes likely to fail together, including sympathetic failures.

Back Pressure Control Valves and Discharge Conditions
Details of any control valves in the system, particularly any used to main positive pressures within the system. Details of the systems discharge are also required (cooling tower, river discharge, closed circuit with pressure vessel etc).

Isolation Valves
Isolation valves may be installed throughout the system to allow isolation of any section. If it is requested that the precise characteristics of these valves are modelled, the valve manufacturer and type details will be required.

Spring Loaded Relief Valves
If spring relief valves are fitted that following data is need:

• Orifice letter or area.
• Set point.
• Percentage accumulation.
• Balanced bellows or normal.

Burst / Rupture Disc
If burst discs are fitted that following data is need:

• Rupture disc size (diameter).
• Rupture pressure.

Air Valves / Vacuum Breakers
If any automatic air valves or vacuum breakers are incorporated on the system (usually on high points), the following is required:

• Valve type and manufacturer (*).
• Valve size.
• Valve location and elevation.

Duty Flowrates and Pressures
The design duty flowrates and the pressures that are expected to be used above and below system (this may be available from the UFD’s).