Heavy Pressure Vessel Fabrication
The teams at DIALOG Fitzroy in Brisbane and in New Plymouth, worked together to tender and win a contract to replace a High Pressure Feedwater Heater at a large power station in NSW. DIALOG Fitzroy have extensive capability and expertise in all facets of heat exchanger fabrication and installation and applied this to this particularly difficult project.
The HP Heater (heat exchanger) is very large, with a shipping weight of well over 44 tonnes. It was a very technically complex build with allowances for installation manways, and accordingly it was decided to fabricate this unit at our heavy pressure vessel workshops and primary fabrication facilities in New Plymouth, NZ. At the request of the owners and after discussion with our engineers, several alterations to the original design were incorporated into the new unit, managed by DIALOG Fitzroy in New Plymouth.
DIALOG Fitzroy Australia with the assistance of their subcontractors, managed and executed the very difficult removal of the old Heater and installation and hook-up of the new unit. The Heater is situated on a level above the turbine floor inside the power station and removal/installation was via a very tight opening in the floor adjacent. Consequently, an extremely comprehensive and detailed lifting and movement management plan was developed to ensure that all technical issues were addressed and risks were managed. We acquired floor loading data to ensure that the mezzanine floor could support the heater as it was moved across to the loading bay and ensured all grating was covered with steel plate to support the heater between floor support beams.
Removal of the old and installing the new unit involved hanging and tilting the Heater for it to fit through the opening. Care was taken to ensure the positioning of the chain hoists in relation to the lifting bay was optimised, to facilitate lowering/lifting the heater to/from the turbine floor.
Inlet and Outlet nozzles were surveyed and checked using two different methods to verify cut lines, the Heater position was surveyed and reference points established to ensure that the new heater was going be setup correctly for level controls and positioning in relation to the main pipework.
The extensive planning and preparation carried out our Australian based team ensured the Heater was back on line exactly according to schedule. This is a great expression of DIALOG Fitzroy's ability to support our customers all the way from design, fabrication, removal and installation, and maintenance.