15 August 2003
Casey Fuel Transfer
On Thursday morning, as I write this, Casey is being buffeted by our strongest blizzard yet, around 90 knots with gusts of over 100 knots (about 180 kph).
|The top fuel farm: a year's supply of precious fuel. August 2003 Photo I Harris|
Fortunately earlier this week we completed one of the bigger weather critical station tasks during a brief spell of calm and mild weather. Casey has 2 fuel tank 'farms', a 'bottom farm' at the wharf (the original fuel storage for the old Casey tunnel station) and a 'top farm' at the current station. The two farms are not connected by fixed piping. Each farm holds approximately one year's supply of fuel. During the year, as the top farm empties during the later part of the year, the fuel in the bottom farm is pumped up to the top farm through a temporary hose connection, in order to leave the bottom farm tanks near empty for the coming refueling at the station re-supply. Any leakage or loss of fuel during the process would be a very major concern. As the job requires plenty of labour to supervise both ends of the operation and continually check the hose for fuel leaks, all the available expeditioners on station took part in a roster to cover the anticipated 36-48 hours of continuous operation. Casey Plant Inspector 'Bloo' Campbell takes up the story.
Fuel is the life blood of an Antarctic station and the operation of transferring fuel around the station is an essential and critical task that needs to be well organised and carefully carried out.
|Dieso Andrew checks the hose connection to the pump at the lower farm. August 2003 Photo I Harris|
At Casey this week, the annual task of transferring the fuel from the bottom fuel farm to the top fuel farm was cleanly executed without any spillage. A total of 390 000 litres of SAB (Special Antarctic Blend ) diesel fuel was transferred through a 'lay flat hose' connecting the fuel installations together, over a distance of approximately 1 kilometre.
The operation began early last week with the survey of the bottom fuel farm and the assessing of the equipment needed to complete the task. The fuel farm plumbing system was dug out from below several metres of snow and all the necessary plumbing was exposed allowing access to the couplings and valves. All the access to the station fuel lines were exposed through some careful digging and everything was checked prior to starting the operation.
|The lay flat hose running up to the top farm at the station. August 2003 Photo I Harris|
A small Atlas Copco compressor was de-blizzed and the lay-flat hose reel was recovered from below its layer of snow. The mobile fuel pump unit was brought out of storage from within the green store and all of this equipment was taken to the dieso's shed to be serviced and functionally checked prior to the operation.
Lighting was checked and the equipment was moved into place during Monday to await the predicted envelope of calmer weather. We had calculated the approximate time needed and we were looking for a period of less that 15 knot winds for approximately 36 hours. Everything was in place awaiting the weather on Tuesday… Some anxious moments during Monday night as the wind was heard gusting to blizz strength and blowing snow around in the wee hours of Tuesday morning.
|Lay flat hose and reel looking back down the hill towards the lower farm. August 2003 Photo I Harris|
Tuesday arrived with a slight breeze and reasonably clear conditions. The station team sprung into action, uncoiling the large 'lay flat' hose, which had to be dragged across the snow from the refueling pipeline that connects the top fuel farm to the main power station and connect the bottom farm into this network. The uncoiling of the hose was carried out efficiently and quickly with the team carefully hauling manually the hose carefully around a rocky out crop near to the bottom farm. This hose covers a distance of approximately one kilometre across the snow.
With the hose in place, a functional pressure test of the hose was carried out to check for any possible leakage and to test the safe working pressure of the entire system. This test was achieved by the pressurizing of the entire system utilizing the small compressor and pressurizing the system to a pressure above the expected fuel pump pressure. With all checks satisfactorily completed, fuel was then pumped into the hose and the refueling process began in earnest.
Pumping of fuel began at 0945 hrs and the fuel lines were patrolled every half hour throughout the entire operation. The flow rate was continually checked by manually dipping the fuel tanks at each farm to establish the amount of fuel was actually being transferred and not lost elsewhere through a leakage. This operation continued until 0600 hrs on Wednesday morning without any interruptions to the pumping schedule.
The entire operation ran like clockwork thanks to the dedication and efforts of all involved to make this process efficient and safe.