In position repair of an air cooler header box

Air Cooler Header Box, In Position Repair

Air cooled heat exchanger header box repaired in position

CompanyOverview

L&A Pressure Welding is an industrial assets manufacturer of pressure equipment, primarily servicing energy, water and chemical suppliers and distributors.

The business was established in 1981 and operates from a 4,000 square metre site at Revesby in south west Sydney.

Fabricated pressure equipment from the workshop

An L&A Fabrication Example

L&A’s core business is the design and fabrication of medium to large heat exchangers, pressure vessels, piping skids and gas lines. It also provides site fabrication and welding services related to these assets.

Tube to tubesheet welds in a heat exchanger

Tube to Tube Sheet Welding Example

An Interesting Challenge

In 2015 the company was approached by a global energy company with an unusual problem.

The company in question had a large air-cooled heat exchanger, showing signs of material failure in the plug sheet on one of the headers. The heat exchanger was a vital component of their gas processing line.

Plug sheet cut free of the air cooler header box

Plug Sheet Cut Free of Box

It needed to be repaired quickly, it needed to meet a very high degree of fabrication quality assurance and it was required urgently to meet contractual gas supply dates.

A local Australian solution was required to suit the timeline.

L&A Takes Up The Challenge

L&A’s engineering and production teams, worked extensively with the client to configure a quality solution to their problem.

The repair scope included:

  • Investigation into the material failure using a series of destructive and non-destructive examinations
  • A re-design of the header
  • Fabrication quality assurance verification
  • Confirming that material integrity of the remaining pressure envelope was ‘fit for service’.

The real challenge; was to install the re-designed plug sheet, on-site and in position with the minimum of disruption or full dismantling of the air cooler.

Root run and hot pass on the bottom plate of the header box

Bottom Plate Root Run & Hot Pass

Working in close coordination with the client, L&A could focus its expertise and efforts on the pressure equipment design aspects and fabrication, while the client supported project management & site coordination activities that were needed to turn the repair around in the very tight time frame.

Top plate assembled onto the header box

Top Plate Assembly

The outcome was a successfully repaired, tested and re-certified Air Cooler ready for service in time for gas on.

End plate being welded onto the header box

End Plate Welding

Through the success of this project the client ordered several additional complete air coolers from L&A and in doing so provided a valuable investment in local engineering and fabrication capability and Australian manufacturing.

Final assembly of the repaired air cooler header box

Final Assembly