摘要 |
An exterior surface portion of a metal tube (30) is bonded to a surface portion of a bore (11) in a metal tubesheet (10) by detonating an explosive bonding charge (31) inside the tube (30) adjacent a front face (13) of the tubesheet (10). The bonding charge (31) consists of nitroguanidine, and is contained within a polypropylene container comprising a cup structure (21) and a header structure (22). The cup structure (21) forms a receptacle for the bonding charge (31), and positions the bonding charge (31) at the proper depth within the tube (30) to achieve the desired bonding effect. The header structure (22) overlies and shapes the bonding charge (31), and contains a transfer charge (44) and a firing charge (45) for initiating detonation of the bonding charge (31). A firing assembly for initiating detonations of firing charges (45) in tubes (30) arranged in a plurality of linear arrays comprises a corresponding plurality of firing rails (24) and an initiation rail (27). Each firing rail (24) is secured to the header structures (22) of a corresponding linear array of bonding charge containers, so that a linear charge (25) secured to the firing rail (24) can initiate detonation in sequence of the individual firing charges (25) of the corresponding linear array. An initiation rail (27) crosses each of the firing rails (24), so that a linear initiation charge (26) secured to the initiation rail (27) can detonate each of the linear charges (25) on the various firing rails (24) in sequence. |