Armstrong, Nikaido, Marmelstein, Kubovcik & Murray
Method of reforming existing gas pipe by repairing joint portions thereof
 The present invention provides a method of repairing the joint portions of an existing gas pipe by a repairing device which is movable inside the pipe under remote control. The repairing device can be moved into and out of the gas pipe through a work opening formed in an upper portion of the gas pipe by boring means with gas flowing through the pipe and free of the hazard of gas leakage. This reduces the labor required for forming the work opening to start the repair work and for restoring the work opening portion to complete the repair work, consequently assuring a shortened work period and a reduced cost. 
Osaka Gas Co., Ltd. Osaka Bousui Construction Co., Ltd. Toho Gas Co., Ltd.
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F16L F16L Y10T F16L
inventional inventional additional inventional
Masaaki Koichi Yoji Yutaka Mitsuhide Yasuo Yasuo
Ohinata Yasui Mori Sugiki Fujita Shimazaki Miyazaki