February 2008 -- In 2007/8 a pioneering HDD project was started using Trenchless Technology on the Berri Causeway and Abu Ali Island on the Persian Gulf coast of Saudi Arabia. Two parallel 3,050 meter long steel pipelines were to be installed under the bay. The smaller one to be used as an oil trunk line (24") and the larger one with a total steel pipe weight of more than 1,500 tonnes will serve as a water injection line (30"). Previously published press releases claimed these as the 'world's longest undersea HDD crossings ever undertaken.
In November 2008 TT-UK were contacted by the Middle East specialist HDD Contractor Digital Connection Co Ltd of Al-Khobar, Kingdom of Saudi Arabia (KSA). They sought technical advice and assistance in the recovery of a 42" hole-opener that had become stuck along with the 3 km drill string beneath the seabed during a pre-ream pass on the second of two under sea pipeline crossings.
The 'Berri Causeway' pipeline project in the Middle East (with high profile exposure to the Trenchless technology industry) was always seen as a big challenge, for example the length of the crossings but also the dimensions of the pipeline which would weigh more than 1,525 tonnes.
Whilst the first 24" oil pipeline had previously been successfully installed, unforeseen delays between the drilling process over a 12 week (non working) period had caused the drill string and the 42" hole-opener to become stuck on the second (30") pipeline crossing/installation.
TT-UK renowned for their expertise in the supply and service of their high quality manufactured Trenchless Technology Equipment had little time to provide a solution to releasing the 3km stuck drill string and 42" hole-opener.
However, emergency discussions between TT-UK, the main contractor and the local drilling contractor quickly led TT-UK to respond to the challenge and recommend utilizing their 'powerful' Grundoram Taurus impacting hammer combined with steel pipe adaptation's which were designed and formulated to transfer dynamic impact performance energies through special steel fabrications adapted to the drill string via the Grundoram dynamic impacting hammer.
Whilst similar successful undertakings have previously been carried out world wide, few have been attempted for releasing stuck drill rods over this exceptionally long distance with each drill rod weighing 480kgs.