Removing deposits to provide accurate inspection results
Ensuring gas coolers are cleaned back to bare metal in preparation for inspection is a prerequisite on all offshore oil platforms. Operators like to work with specialist cleaning contractors who work safely, have trained technicians and arrive on the platform with cleaning technology ready for all eventualities. When a cleaning contractor can also provide the inspection services that are required the operator benefits from only having to liaise with one company who then take responsibility for the entire project. Here Tube Tech details two gas cooler cleaning contracts in two very different locations.
360° Surface Contact via Bespoke Unblocking & Polishing Heads
A High Pressure Compressor Discharge Cooler on a North Sea platform developed leaks. To establish the extent of damage there was a need to unblock and clean the tube bores in preparation for full Eddy Current and IRIS inspection. Tube Tech were asked to mobilise quickly with the remit that no one knew what level or how much fouling would be found in the tubes – come prepared for the worst was the brief from the client.
An initial flood test inspection of the gas cooler showed two leaking tubes. Tube Tech used bespoke unblocking heads to remove deposits from the tube bores whilst simultaneously polishing the bores. All tubes were cleaned and confirmed as very acceptable for IRIS inspection following which the tubes were dried. Eddy Current and IRIS inspections were performed to provide the client with a clear idea of the integrity of the remaining gas cooler tubes.
Scott Donson, Technical Sales Manager: “Having a team of offshore trained operatives ready to mobilise at short notice was a big bonus for this client. We were able to clean and achieve the desired standard quickly, and above all safely, allowing very searching inspection to take place. Ensuring the platform’s shutdown progressed with the minimum of downtime and no incident was paramount”.
Gas Coolers Cleaned and Inspected in Nigeria
Tube Tech cleaned and inspected a number of gas coolers, including Koch / Brown Fin tube units, on one of the largest FPSOs (Floating production storage and offloading) units in the world off the coast of Nigeria. This was the first time the gas coolers had been cleaned in preparation for a detailed integrity inspection since the unit was built three years ago and Tube Tech was awarded the contract due to their ability to both clean specialist small bore tubes (including twisted tube) and inspect the coolers.
The client provided Tube Tech with a very tight timeline in order to transport both equipment and crew out to site. Cleaning and inspection of the gas coolers took place directly beneath FPSO flare so high temperatures were a challenge. Tube Tech technicians had a limited working area as a host of other operations were taking place during the TAR (turnaround) so constant liaison with scaffold crew, fitters, riggers etc was essential.
Tube Tech used their unique SafeFlex system with bespoke unblocking and polishing heads to clean the gas cooler tubes. These techniques and technologies were able to remove coke formations and achieve the standard suitable for IRIS inspection without using excessive pressures or rigid semi-automated equipment. Tube Tech also conducted an IRIS inspection which showed the tubes on the gas coolers to be in good condition.
Scott Donson, Technical Sales Manager: “With so many different disciplines in one very tight area the client was amazed at how well the TAR personnel were able to integrate thereby allowing each discipline to conduct its work in an efficient safe manner. This was an extremely challenging contract that evolved day by day, but was executed within the tight timeframe and to the specifications given by the client.” Tube Tech received the following feedback from their client’s Superintendent “Tube tech did a very professional job and it was a privilege to work with such team players. They were very professional and took safety as their prime driver. All members of their team participated fully in all safety programs. Their equipment was all fit for purpose and was well maintained with all relevant paperwork and certs. These were available on request. They completed all their tasks on schedule and with zero incident and accident”.
Always aware of the pressures placed on offshore operators Tube Tech continue to invest in research and development to find safer, faster and more effective methods to clean heat transfer equipment on offshore platforms. Appreciating the critical nature of most offshore cleaning contracts the company constantly questions the ‘this is how it has always been done’ nature of traditional cleaning techniques and Tube Tech’s clients are impressed with the level of commitment they receive.