Page 54 - Wire Rope News & Sling Technology
P. 54

continued from previous page
         tate a tunnel-boring machine (TBM) at
         a major subway infrastructure project
         in Singapore.
           The site is part of the landmark Gar-
         dens  By The  Bay MRT  Station proj-
         ect, a future underground Mass Rapid
         Transit station on the Thomson-East
         Coast Line in Marina South.
           The TBM, manufactured by Hitachi
         Zosen  Corporation,  measured  22ft.
         (6.7m) in  diameter and  weighed  570
         ton (520 tonne) It had completed an ini-
         tial 2,225ft (679m) tunnel—the HT300
         was  used during  the initial  assembly
         and then at multiple other stages of
         the project. Now the TBM needed to be
         repositioned to begin its next boring as-
         signment. The HT300 and TT900 com-
         bined to move and rotate the TBM in
         its entirety, 100 ft. (30m) underground.
         After two days of preparation work and   After two days of preparation work and planning, the actual rotation was completed in
         planning, the actual rotation was com-  just one hour.
         pleted in just one hour by skidding it
         onto the turntable, jacking down and   and pin set and can be leap-frogged to   Slide’s TT500-10,  designed to accom-
         rotating 180 degrees.              slide longer distances.            modate  extra cylinders and rotating
           Jefferson Yee, general manager, Yu   The  HT300  remained  in  place  while   force. It  was shipped to Singapore in
         Sin  Engineering  Work  Pte Ltd, said:   the rotation was completed in one con-  an open-top container via sea freight.
         “Initially  the  plan  was  to  dismantle   tinuous motion, with the Turntable pus   Janine Smith, vice president at Hy-
         and re-launch  [the TBM], but this   cylinders automatically resetting into   dra-Slide explained: “It is a simple sys-
         would have taken a long time and we   ratchets after each push. The TT900,   tem to operate. We have designed our
         wanted to explore  the option of a U-  which had already been lowered into the   Turntables with the same safety princi-
         turn.  After consulting  with  Hydra-  shaft using a 250-ton capacity crawler   ples as our skidding systems – there are
         Slide on the technical possibilities we   crane,  is  more  commonly  used  to  turn   no winch lines or holdbacks required,
         proceeded with the alternative option,   transformers or generators during han-  the push cylinders automatically reset
         which resulted in a huge time savings.”  dling or installation, but it is suited to   into specially designed ratchets on the
           Prior to the rotation, the HT300 slid   rotation of any heavy or oversized loads   side of the turntable, and there is no
         the TBM 40 ft. (12m) using 4 rails   and Yee reported that it demonstrated   manual handling of any components re-
         and four push cylinders to increase   its versatility and reliability.  quired during operation. We spoke with
         the HT300’s overall capacity. The    He said: “We were familiar with the   the crew in Singapore when a ques-
         system’s standard track lengths are   HT300 after the first sliding operation,   tion arose but they did not require any
         10ft. and 19ft. (3m and 6m) but Hy-  but the TT900 proved to be just as fast,   training on the product turntable. To
         dra-Slide can customize track lengths   safe and easy to operate.”    the best of our knowledge, it is the first
         to suit almost any requirement. The   The  TT900-10, ordered by Yu  Sin   time the turntable has been used under-
         tracks are connected by a simple lug   this spring, is a modification of Hydra-  ground on a tunneling project; Yu Sin

         54     Wire Rope News & Sling Technology   October 2017
   49   50   51   52   53   54   55   56   57   58   59