| 摘要 |
<p>PURPOSE:To shorten the length of an arm by installing a sliding frame and a support frame to a boom supported by an upper revolving superstructure, inserting an internal arm into an external arm body supported by the support frame and mounting a catching device to the internal arm. CONSTITUTION:A boom 4 is supported to an upper revolving superstructure 3 so as to rise and fall freely. A sliding frame 7 is supported to the boom 4 so as to rise and fall freely. A support frame 15 is set up to the sliding frame 7 so as to be able to be vertically shifted. A cylindrical external arm body 17 is supported to the support frame 15 so as to be able to be turned in the circumferential direction, and an internal arm body 21 is inserted into the external arm 17 so as to be moved along the external arm 17. A catching device 33 is installed at the lower end section of the internal arm body 21. The support frame 15 is lowered to the sliding frame 7 and pipe laying work is conducted, and the sliding frame 7 is brought down when a pipe laying machine is removed.</p> |
