The Polish contractor RABA of Raczki had to drill 2 quite long bores in Mala Huta nearby Suwalki, 30 km from Lithuanian boarder. The first bore was 240 m (795 ft) long under the lake Krzywe. The second bore was 325 m (1’075 ft) long under a swamp. RABA used their TERRA-JET 5415 S.
The operator Dawid Bujarski has a lot of experience with his TERRA-JET. The ground was very soft. So he decided to drill very fast. The pilot bore of the 325 m took 3 hours, the backreaming with the backreamer 260 mm (10”) approximately
4 hours. To our knowledge nobody else has ever drilled so fast with a TERRA-JET. So this is a TERRA World Record!
The 240 m long bore underneath the lake was also fast. During the pilot bore they located the drill head from a boat. The complete “lake bore” took 7 hours for the pilot bore and the pipe pulling. In both bores they pulled in two HDPE pipes with OD 110 mm (4.3”) and OD 63 mm (2.5”). These pipes are for fresh water and for sewer under pressure. These job sites prove, how productive HDD bores can be done, if an experienced operator drills with a modern TERRA-JET.
The locating was done with a locating system i-Track. The depth of the lake was 9.80 m (32 ft), the total depth of the pilot bore 13.4 m (45 ft). The 325 m long bore required 8’000 ltrs (2’000 gal) of Bentonite.
The operator of the TERRA-JET 5415 S was Dawid Bujarski, the locating specialist Marcin Winiarski. The responsible manager for the project was dipl. Engineer Pawel Kruszewski.
M/s RABA is a specialist in pipe and cable laying. The company was founded in the year 1991. Besides contracting they are a successful dealer for Wavin pipes and fittings.