US 4,527,623 A · Kinetically bonded tubes and tubesheet

Abstract

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.

Claims98

Dependent claims

An apparatus for bonding an exterior surface portion of a metal tube to a surrounding surface portion of a bore in a metal tubesheet, said bore being separated from an adjacent bore in said tubesheet by a ligament portion of said tubesheet, said ligament portion having a transverse dimension less than a transverse dimension of either bore, said apparatus comprising:

(a) an explosive bonding charge;
and
(b) container means housing said bonding charge, said container means functioning to position said bonding charge within said tube inside said bore preponderantly below a front face of said tubesheet, said container means shaping said bonding charge so that an outwardly facing surface of said bonding charge is generally concave, forces resulting from detonation of said bonding charge as shaped and positioned by said container means thereby causing a metallurgical bond to be formed between said exterior surface portion of said tube and said surrounding surface portion of said bore, said bond being strongest adjacent said front face of said tubesheet.

An explosive package for use in bonding an exterior surface portion of a metal tube to a surrounding surface portion of a bore in a metal tubesheet, said bore being configured so that said surrounding surface portion of said bore is spaced apart from said tube adjacent a front face of said tubesheet and so that said tube has a clearance fit within said bore adjacent a rear face of said tubesheet when said tube is positioned in said bore, said explosive package comprising:

(a) a cup structure configured to receive a bonding charge;
and
(b) a header structure configured to receive a transfer charge, said header structure being further configured for insertion into said cup structure so that a bottom portion of said header structure shapes said bonding charge within said cup structure and maintains said transfer charge in contact with said bonding charge, said bottom portion of said header structure being predominantly non-perpendicular to said surface portion of said bore, said transfer charge being used in initiating detonation of said bonding charge;
said explosive package being insertable into said tube so that a spacer portion of said cup structure abuts said front face of said tubesheet, said bonding charge thereby being positioned preponderantly below said front face of said tubesheet so as to cause a metallurgical bond to be formed between said exterior surface portion of said tube and said surrounding surface portion of said bore upon detonation of said bonding charge, said metallurgical bond being strongest adjacent said front face of said tubesheet.

1 more element

A system for bonding a plurality of metal tubes to a metal tubesheet, each tube being positioned in a corresponding bore of a plurality of bores in said tubesheet, said bonding system comprising:

(a) a plurality of explosive packages, each one of said explosive packages being insertable into a corresponding one of said tubes, each explosive package containing a bonding charge housed in a container, said container being configured to position said bonding charge within said tube adjacent a front face of said tubesheet so that said bonding charge is preponderantly below said front face of said tubesheet, said container also being configured to shape said bonding charge so that a surface of said bonding charge facing outwardly from said tube is generally concave, forces resulting from detonation of said bonding charge as positioned and shaped by said container whereby causing a metallurgical bond to be formed between an exterior surface portion of said tube and a surrounding surface portion of said bore, said container also containing means for initiating detonation of said bonding charge;
and
(b) means for activating said means for initiating bonding charge detonations in each of said explosive packages, said activating means causing bonding charge detonations in said plurality of tubes to occur in a temporal pattern that precludes simultaneous bonding charge detonations in adjacent tubes of said plurality of tubes.

A method for bonding a plurality of metal tubes to a metal tubesheet, each tube being positioned in a corresponding bore of a plurality of bores in said tubesheet, said method comprising the steps of:

(a) inserting a corresponding explosive package of a plurality of explosive packages into each tube, each explosive package containing a bonding charge housed in a container, said container being configured to position said bonding charge within said tube adjacent a front face of said tubesheet so that said bonding charge is preponderantly below said front face of said tubesheet, said container also being configured to shape said bonding charge so that a surface of said bonding charge facing outwardly from said tube is generally concave, forces resulting from detonation of said bonding charge thereby causing a metallurgical bond to be formed between an exterior surface portion of said tube and a surrounding surface portion of said corresponding bore;
and
(b) initiating detonation of said bonding charges in said explosive packages, said bonding charge detonations occurring in said plurality of tubes in a temporal pattern that precludes simultaneous bonding charge detonations in adjacent tubes of said plurality of tubes.

A heat exchanger comprising a plurality of metal tubes bonded to a metal tubesheet, each tube of said plurality of tubes being positioned in a corresponding bore of a plurality of bores in said tubesheet, said bond consisting of material from said tube crystallographically interpenetrating material from said tubesheet, said heat exchanger being produced by a process that comprises:

(a) inserting a corresponding explosive package of a plurality of explosive packages into each tube of said plurality of tubes, said corresponding explosive package comprising a bonding charge housed in a container, said container being configured to position said bonding charge within said tube preponderantly below said front face of said tubesheet, said container also being configured to shape said bonding charge so that a surface of said bonding charge facing outwardly from said tube is generally concave, forces resulting from detonation of said bonding charge thereby causing said bond to be formed;
and
(b) initiating detonations of bonding charges contained in said plurality of explosive packages inserted in said plurality of tubes, said bonding charge detonations occurring in a temporal pattern that precludes simultaneous bonding charge detonations in adjacent tubes for said plurality of tubes.

A method for bonding each tube of a plurality of metal tubes to a corresponding bore of a plurality of bores in a metal tubesheet, said bores being disposed in said tubesheet in parallel linear arrays, a bore of a first linear array being adjacent at least one bore of a second linear array, said method comprising the steps of:

(a) positioning a first set of said tubes in said first linear array of bores, each tube of said first set of tubes being positioned in a corresponding bore of said first linear array of bores;
(b) inserting a first set of explosive packages of a plurality of explosive packages into said first set of tubes, each explosive package including a container that houses a bonding charge, said container being configured for insertion into one of said tubes positioned in a corresponding one of said bores so as to position said bonding charge adjacent a front face of said tubesheet, whereby detonation of said bonding charge causes bonding of an exterior surface portion of said tube to a surrounding surface portion of said corresponding bore;
(c) inserting first plug means into said second linear array of bores, said first plug means bracing the surrounding surface portion of each bore of said second linear array against movement in reaction to a bonding charge detonation in a tube of said first set of tubes positioned in an adjacent bore of said first linear array of bores;
(d) initiating sequential bonding charge detonations in said first set of tubes to cause bonding of the exterior surface portion of each tube of said first set of tubes to the surrounding surface portion of each corresponding bore of said first linear array of bores;
(e) removing said first plug means from said second linear array of bores after said exterior surface portion of each tube of said first set of tubes has been bonded to said surrounding surface portion of each corresponding bore of said first linear array of bores;
(f) positioning a second set of said tubes in said second linear array of bores, each tube of said second set of tubes being positioned in a corresponding bore of said second linear array of bores;
(g) inserting a second set of explosive packages of said plurality of explosive packages into said second set of tubes;
(h) inserting second plug means into said first set of tubes bonded to said corresponding bores of said first linear array, said second plug means bracing each tube of said first set of tubes against movement in reaction to a bonding charge detonation in a tube of said second set of tubes positioned in an adjacent bore of said second linear array of bores;
and
(i) initiating sequential bonding charge detonations in said second set of tubes to cause bonding of the exterior surface portion of each tube of said second set of tubes to the surrounding surface portion of each corresponding bore of said second linear array of bores.

7 more elements

A system for bonding each tube of a plurality of metal tubes to a corresponding bore of a plurality of bores in a metal tubesheet, said bores being disposed in said tubesheet in parallel linear arrays, a bore of a first linear array being adjacent at least one bore of a second linear array, said bonding system comprising:

(a) a plurality of explosive packages, each one of said explosive packages being insertable into a corresponding one of said tubes, each explosive package including a bonding charge housed in a container, said container being configured to position said bonding charge within the corresponding one of said tubes adjacent a front face of said tubesheet when said corresponding one of said tubes is positioned in a corresponding one of said bores, said container also containing means for initiating detonation of said bonding charge;
(b) first firing rail means for sequentially activating the means for initiating detonations of bonding charges in explosive packages of a first set of said explosive packages when the explosive packages of said first set of explosive packages are inserted into adjacent tubes of a first set of said tubes, said first set of said tubes being positioned in adjacent bores of said first linear array of said bores;
(c) first plug means for insertion into said second linear array of said bores when said first set of said explosive packages has been inserted into said first set of said tubes, said first plug means bracing surface portions of the bores of said second linear array of said bores against movement in reaction to bonding charge detonations in the tubes of said first set of said tubes positioned in said first linear array of said bores;
(d) second firing rail means for sequentially activating the means for initiating detonations of bonding charges in the explosive packages of a second set of said explosive packages when the explosive packages of said second set of explosive packages are inserted into adjacent tubes of a second set of said tubes, said second set of said tubes being positioned in adjacent bores of said second linear array of said bores after said first plug means has been removed from said second linear array of said bores following bonding charge detonations in said first set of said tubes;
and
(e) second plug means for insertion into said first set of tubes bonded to corresponding bores of said first linear array of said bores when said second set of said explosive packages has been inserted into said second set of said tubes following bonding of an exterior surface portion of each tube of said first set of said tubes to a surrounding surface portion of a corresponding bore of said first linear array of said bores, said second plug means bracing said first set of said tubes against movement in reaction to bonding charge detonations in the tubes of said second set of said tubes;
said first firing rail, first plug means, second firing rail and second plug means cooperating to prevent significant spalling of ligaments between adjacent bores in different linear arrays of said bores.

4 more elements

An explosive package for bonding an exterior surface portion of a metal tube to a surrounding surface portion of a bore in a metal tubesheet, said surrounding surface portion of said bore being spaced apart from said tube adjacent a front face of said tubesheet, said explosive package comprising a cup structure containing a bonding charge, said cup structure being configured for insertion into said tube to position said bonding charge so that detonation of said bonding charge causes a metallurgical bond to be formed between said exterior surface portion of said tube and said surrounding surface portion of said bore, said explosive package further comprising a header structure containing a transfer charge and a firing charge, said firing charge being in contact with said transfer charge so that detonation of said firing charge initiates detonation of said transfer charge, said header structure being configured for insertion into said cup structure over said bonding charge to position said transfer charge in contact with said bonding charge so that detonation of said transfer charge initiates detonation of said bonding charge, said header structure comprising a pair of arms configured for grasping a firing rail means for initiating detonation of said firing charge.

A protective covering for a front face of a metal tubesheet, said protective covering comprising a plurality of plugs, said plugs being interchangeable with each other, each plug including:

(a) a supporting structure comprising a rigid base plate and an elongate member extending generally perpendicularly from said base plate, a proximal end of said elongate member being secured to said base plate and a distal end of said elongate member being screw-threaded;
(b) a resilient member of generally circularly cylindrical configuration, said resilient member having an axial bore therethrough, said bore of said resilient member activating said elongate member of said supporting structure;
(c) a rigid top plate having a bore therethrough, said bore of said top plate receiving said elongate member of said supporting structure;
and
(d) a nut threadably securable to said distal end of said elongate member of said supporting structure when said resilient member is sandwiched between said base plate of said supporting structure and said top plate;
each plug being insertable into a corresponding metal tube bonded by a metallurgical bond to a surface portion of said corresponding bore in said tubesheet to protect said bond by bracing said tube against movement relative to said corresponding bore in reaction to detonation of a bonding charge in an adjacent bore in said tubesheet, said top plate of each plug overlapping said front face of said tubesheet when each plug is inserted into said corresponding tube bonded to said corresponding bore in said tubesheet, top plates of all of said plugs being substantially identically configured, the top plate of each plug being in extended contact with the top plate of at least one other of said plugs when all of said plugs are inserted into corresponding tubes bonded to corresponding bores in said tubesheet, the top plates of all of said plugs collectively covering all otherwise exposed areas on said front face of said tubesheet during detonation of bonding charges in adjacent bores in said tubesheet, said top plates of said plurality of plugs thereby protecting said front face of said tubesheet from damage due to detonation of said bonding charges.

3 more elements

Dependencies are inferred from the claim text.

Kinetically bonded tubes and tubesheet

Life of this patent

Kinetically bonded tubes and tubesheet

Life of this patent

Abstract

Claims98