Not something that would happen often, but when Airdrill got a call from a Japanese government funded aid project manager involved in a harbor deepening program in Northern Vietnam after only 20% of the required work had been completed on some 18 months, we knew we had to do something special.

The level of local support for any rigs on site was minimal however there were two big diesel powered generating sets on a barge available as a starting point. With a 2-4 meter tide run plus 1-2 meters of swell and the aid of GPS positioning a rig with a fully floating drill head was designed. To achieve the desired production rates the client requested 2 rigs and to reduce time consuming moving of the barge the rigs were mounted onto rails along one side of the barge.

Diesel powered rigs posed a fire hazard as well as being noisy and needing frequent maintenance so a system using an electrically driven hydraulic power pack on each rig was selected. All electrics were waterproofed and indeed no time was lost over 6 months of drilling 24 hours a day due to electrical matters aside from a couple of broken lights!

Once in place and commissioned the rigs drilled and cased a hole every 30 minutes while the original contractor had been drilling 2-4 holes per 24 hours using 4 elderly diamond drilling rigs over the previous period. While on site Airdrill people trained local crews in the operation and servicing of the rigs.

Once a pattern was completed it was charged and fired something that became a daily event for the local fishermen to come around after a blast and to collect the stunned fish. Another novelty on site was the never-ending parade of sampans rowing past with all manner of goods offered for sale!

The drilling was done using 3 ½ inch RC pipe and a Drillquip RC hammer to ensure that the holes were clean after we left them as well as allowing the blasting engineers to examine the sample to design their shots. A single 900/350 compressor was used most of the time although there was a back up unit on the barge.

We had 8 nationalities on board with no common language and some funny misunderstandings from time to time. However no injuries or serious LTI's occurred during the job which was a tribute to the efforts of all the crew with Fujimoto san the Japanese engineer deserving a special mention for his efforts.

Got a strange job? Give Airdrill a call and see what we come up with!