发明名称 |
REPLACING MAINS BRITISH GAS CORPORATION |
摘要 |
<p>The invention relates to a method for replacing or preparing an existing main, particulary an cast iron gas main, with a new main. The new main may be of any convenient plastics material such as polyethylene or pvc. The method comprising fracturing the existing main and maintaining sufficient clearance through the fractured main for movement therethrough of a new main or a liner for the fractured main. The liner is of a much tougher wear resistent plastics material and serve as a protective sleeve for the new main when the new main is subsequently moved into the liner.</p> |
申请公布号 |
GB8430977(D0) |
申请公布日期 |
1985.01.16 |
申请号 |
GB19840030977 |
申请日期 |
1984.12.07 |
申请人 |
BRITISH GAS CORPORATION;RYANS & SONS LTD, D J;RYANS & SONS LTD |
发明人 |
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分类号 |
F16L1/024;A01N29/00;A01N61/00;A01N65/00;E21B7/30;F16L1/00;F16L55/16;F16L55/165 |
主分类号 |
F16L1/024 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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