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Tools for the Industry

Tools for the Industry In contrast to ball bearings, they are also not sub­ jected to 'brinclling' under the rapidly interrupted Tools for the Industry hammering loads. High machine utilization is maintained on all floor model swagers by quick-opening cam-operated gates. A Selection of Equipment of Use in the Production and Maintenance With this feature average set-up time for typical operations is a matter of minutes. of Aircraft, Missiles, Space Vehicles and their Components Before describing the range of machines available it must be pointed out that the selection of the correct machine size for a particular swaging operation ROTARY SWAGING MACHINES reducing raw bar or tube to complex shapes—a feed depends primarily upon the strength of the machine of 8 in./sec. has already been mentioned—Torrington head. This must withstand the load calculated from The Torrington Company of Torrington, Connecticut, machines have been designed to permit rapid setting; the projected area of material under compression and U.S.A., has accumulated almost 100 years experience changes of set-up are accomplished in a few minutes. the tensile strength of the material being swaged. of rotary swaging machines. This wealth of experience Furthermore, tooling is said to be extremely simple The specified diametrical capacity of a machine is combined with the need to meet the exacting require­ and, incidentally, inexpensive. The process is easily based upon an ultimate tensile strength of 60,000 ment of the highly-specialized swaging trade, has understood and requires no special training. Labour lb./sq. in. and is the mean diameter of the tapered resulted in the development of swaging machines that costs are therefore relatively low and this fact com­ length of the die and not the original bar diameter. If are among the best produced today. These American- bines with the increases in productivity and machine a material to be worked has less strength, its mean made machines are now offered for sale, for the first utilization to ensure that the capital investment in a diameter may be increased and vice versa. Altern­ time, to industry in general, and in pursuit of this new rotary swager is quickly recovered. atively, the projected area can be reduced by reducing policy Alfred Herbert Ltd. has been appointed selling The stresses imposed upon a rotary swaging the length under compression in the die. agents in the United Kingdom. machine by two, three or four thousand blows per The Torrington machines range from small bench Rotary swaging is a method of mechanically forging minute on machine elements is very considerable, and models (scries 100, 111 and 211) with rated capacities regular or irregular cross-sections into round ones the prime consideration is given in the machine design from 1/16 diameter (mean diameter) to large floor without loss of material. In Torrington rotary swaging to the ability of the machines to withstand these loads machines, this is achieved with up to 4,000 forging models, the largest having a rated capacity of 2½ in. after several years daily use. If not properly con­ blows per minute. Feeds can be as high as 8 in./sec. for diameter bar or 6 in. diameter tubes. structed, the machines could, literally, 'hammer them­ continuous axial forging of hot or cold materials. These are suitable for pointing and tapering the selves to pieces'. ends of bars and tubes and for straight reductions The process is very popular for pointing, sizing, when the material is fed straight through the die. In shaping, tapering, forming and contouring practically addition to finishing material to the desired shape, any metal either in solid or tubular form. Further­ more, ferrules, terminals and other similar parts can they are also suitable for sizing material for other be swaged over an inner part, such as a cable, to pro­ operations, such as for example thread-rolling, when duce an exceptionally strong bond. the exact diameter bar stock cannot be purchased. However they are used, there will be considerable Finished shape is controlled with a pair of shaped savings in material costs. dies which close on the workpiccc, the dies being Straight reduction can be used for swaging or sizing reciprocated at a high rate in a slot in the end of the machine spindle. Hammer blows are imparted to the wire down to 0·005 in. diameter. dies by round-ended backers, located in the slot For complex profiles that cannot be axially through- behind the dies. These are flung outwards by centri­ fed, four die-closing machines are available. Work can fugal force and violently returned by the action of be placed in these machines in accurately predeter­ striking a series of hardened-steel rollers arranged mined positions and the dies progressively closed. around the spindle. In principle and construction these machines are essentially the same as the Torrington through-feed For forming, contouring, etc., the dies are progres­ machines. They have similar rollers, roll rack, inside sively brought together by the action of wedges; for ring, hollow spindle, etc., and adjustments for die straight reductions the bar or tube is fed axially into the tapered dies, reduction taking place over the length opening and blow pressure are the same. of the taper. The inside diameters of tubes are con­ The primary difference between the two types is the trolled, if necessary, by the insertion of mandrels of use of taper-back dies and the insertion of a wedge the appropriate size. between each die and its backer. The two wedges are supported by a wedge-operating rod by which they Since neither the rollers nor the. workpiece rotate are fed forward to close the dies while they are but the spindle docs, the forging blows follow each rotating with the spindle. other in succession around the periphery of the work­ Wedge rod maximum travel is approximately 2 in. piccc, so producing uniform reduction. The number of but this can be adjusted by easily-set stop collars. blows per minute is approximately equal to 0·6 x r.p.m. x number of rollers. Wedges are connected to their anchorages on the wedge rod without the use of fastenings, so that they There are many areas of the machine shop where may be quickly lifted out and replaced when changing contoured, tapered and other such parts are machined by metal cutting, but if an investigation were made it a set-up. would be found more economical to form them by The performance of Torrington rotary swaging rotary swaging. machines can be considerably enhanced by the type of attachment used for work feeding. A number of The most obvious saving is through the chipless Torrington feeding attachments is available which are method of machining. A swaged part is a hammered also suitable for other applications. They range from part with no waste of material unless end trimming is required. It is clearly uneconomical to expend valuable simple manual equipment to automatic power as­ man hours in manufacturing swarf from expensive sisted models. The front surfaces of the head and base raw materials for the benefit of the scrap merchant. can accommodate a variety of feed attachments with­ out further machining. In contrast to metal cutting, swaging improves the A manual rack-and-pinion model gives sufficient tensile strength and surface hardness of the material mechanical advantage to permit the operator to feed being formed. These changes in physical properties are caused by the flow of the material under the forg­ against steep tapers. Several types of work-holders are ing hammer blows which allows the grain to follow A modern welded fabrication is used for the main available and accurate work alignment is assured. the contour of the form rather than being severed, as structure. Cast-iron was discarded as unsatisfactory Hydraulically-powered models can provide for fully in metalcutting. Furthermore, the material is subjected many years ago, and the present design has been or semi-automatic operation. Work-loading can be to pressure which densifies the surface. Substantial evolved by a company with perhaps the largest con­ manual or automatic and the feed and return cycle improvements are obtained with both ferrous and non- tinuous experience of rotary swaging. can be accurately adjusted to meet all work require­ ferrous materials. Stainless and alloy steels exhibit The head is flame cut from a solid 0·4 carbon steel ments by means of stops and electrical trips. In some these qualities to a greater degree than other metals. billet which provides maximum resistance to fracture models the required cycle may be set up with selector Carbon steels show an increase in tensile strength through strain and metal fatigue. switches on the control panel. of approximately 1,000 lb./sq. in. for each 10 percent All working parts are manufactured from the finest Die-closing machines, which are usually employed reduction in area. grade tool steel, specially hardened and finished, and for short work-pieces, can be supplied with a semi­ easily replaceable hardened-steel wear plates are In addition to increasing surface hardness, the sur­ automatic hydraulic feed. Loading and unloading are located at all friction points. Krupp bearing-quality accomplished manually, but the remainder of the face finish is improved due to a certain degree of steel is used for the inside ring to ensure long working cycle, including clamping, is completely automatic. burnishing that occurs. As a result, the finish work­ life. However, should the ring ever require replace­ The feed cycle is interlocked with the movements of piccc is free from the surface imperfections that are often exhibited by other methods of machining. ment, it can be quickly and easily pressed out of the the wedge-rod which is also automatic. Fast approach Following on this property of swaging, it is found that removable head, and a new one pressed in. and return motions are employed to reduce idle time plated parts may often be swaged without damaging The hollow spindle is driven through a substantial to a minimum. the plating. flywheel which is taper-mounted between the support Roll feeds are available for continuous through- bearings. Impact loads are therefore more evenly Consistent feeding and proper die maintenance can feeding of stock. They may be used either in pairs, one distributed which leads to greatly extended bearing usually result in tolerances of ±0·001 in. and better. at the front and one at the back, or single at the front In many applications, the piece as swaged meets life. or at the back of the machine. Loading is manual or tolerances appropriate for ground parts. Swaged parts The flywheel is easily accessible from the front of the from a magazine. When units are used in pairs, their do not require additional finishing operations to hold machine for hand rotation during machine setting. speeds can, if necessary, be adjusted relative to one close diametrical tolerances or high surface finishes. All bearings are high-quality tapered roller bearings another to compensate for the increased rate at which capable of withstanding both axial and radial thrusts. the reduced diameter work emerges from the machine. Besides being one of the most rapid methods of Aircraft Engineering http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Aircraft Engineering and Aerospace Technology Emerald Publishing

Tools for the Industry

Aircraft Engineering and Aerospace Technology , Volume 36 (2): 1 – Feb 1, 1964
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Publisher
Emerald Publishing
Copyright
Copyright © Emerald Group Publishing Limited
ISSN
0002-2667
DOI
10.1108/eb033843
Publisher site
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Abstract

In contrast to ball bearings, they are also not sub­ jected to 'brinclling' under the rapidly interrupted Tools for the Industry hammering loads. High machine utilization is maintained on all floor model swagers by quick-opening cam-operated gates. A Selection of Equipment of Use in the Production and Maintenance With this feature average set-up time for typical operations is a matter of minutes. of Aircraft, Missiles, Space Vehicles and their Components Before describing the range of machines available it must be pointed out that the selection of the correct machine size for a particular swaging operation ROTARY SWAGING MACHINES reducing raw bar or tube to complex shapes—a feed depends primarily upon the strength of the machine of 8 in./sec. has already been mentioned—Torrington head. This must withstand the load calculated from The Torrington Company of Torrington, Connecticut, machines have been designed to permit rapid setting; the projected area of material under compression and U.S.A., has accumulated almost 100 years experience changes of set-up are accomplished in a few minutes. the tensile strength of the material being swaged. of rotary swaging machines. This wealth of experience Furthermore, tooling is said to be extremely simple The specified diametrical capacity of a machine is combined with the need to meet the exacting require­ and, incidentally, inexpensive. The process is easily based upon an ultimate tensile strength of 60,000 ment of the highly-specialized swaging trade, has understood and requires no special training. Labour lb./sq. in. and is the mean diameter of the tapered resulted in the development of swaging machines that costs are therefore relatively low and this fact com­ length of the die and not the original bar diameter. If are among the best produced today. These American- bines with the increases in productivity and machine a material to be worked has less strength, its mean made machines are now offered for sale, for the first utilization to ensure that the capital investment in a diameter may be increased and vice versa. Altern­ time, to industry in general, and in pursuit of this new rotary swager is quickly recovered. atively, the projected area can be reduced by reducing policy Alfred Herbert Ltd. has been appointed selling The stresses imposed upon a rotary swaging the length under compression in the die. agents in the United Kingdom. machine by two, three or four thousand blows per The Torrington machines range from small bench Rotary swaging is a method of mechanically forging minute on machine elements is very considerable, and models (scries 100, 111 and 211) with rated capacities regular or irregular cross-sections into round ones the prime consideration is given in the machine design from 1/16 diameter (mean diameter) to large floor without loss of material. In Torrington rotary swaging to the ability of the machines to withstand these loads machines, this is achieved with up to 4,000 forging models, the largest having a rated capacity of 2½ in. after several years daily use. If not properly con­ blows per minute. Feeds can be as high as 8 in./sec. for diameter bar or 6 in. diameter tubes. structed, the machines could, literally, 'hammer them­ continuous axial forging of hot or cold materials. These are suitable for pointing and tapering the selves to pieces'. ends of bars and tubes and for straight reductions The process is very popular for pointing, sizing, when the material is fed straight through the die. In shaping, tapering, forming and contouring practically addition to finishing material to the desired shape, any metal either in solid or tubular form. Further­ more, ferrules, terminals and other similar parts can they are also suitable for sizing material for other be swaged over an inner part, such as a cable, to pro­ operations, such as for example thread-rolling, when duce an exceptionally strong bond. the exact diameter bar stock cannot be purchased. However they are used, there will be considerable Finished shape is controlled with a pair of shaped savings in material costs. dies which close on the workpiccc, the dies being Straight reduction can be used for swaging or sizing reciprocated at a high rate in a slot in the end of the machine spindle. Hammer blows are imparted to the wire down to 0·005 in. diameter. dies by round-ended backers, located in the slot For complex profiles that cannot be axially through- behind the dies. These are flung outwards by centri­ fed, four die-closing machines are available. Work can fugal force and violently returned by the action of be placed in these machines in accurately predeter­ striking a series of hardened-steel rollers arranged mined positions and the dies progressively closed. around the spindle. In principle and construction these machines are essentially the same as the Torrington through-feed For forming, contouring, etc., the dies are progres­ machines. They have similar rollers, roll rack, inside sively brought together by the action of wedges; for ring, hollow spindle, etc., and adjustments for die straight reductions the bar or tube is fed axially into the tapered dies, reduction taking place over the length opening and blow pressure are the same. of the taper. The inside diameters of tubes are con­ The primary difference between the two types is the trolled, if necessary, by the insertion of mandrels of use of taper-back dies and the insertion of a wedge the appropriate size. between each die and its backer. The two wedges are supported by a wedge-operating rod by which they Since neither the rollers nor the. workpiece rotate are fed forward to close the dies while they are but the spindle docs, the forging blows follow each rotating with the spindle. other in succession around the periphery of the work­ Wedge rod maximum travel is approximately 2 in. piccc, so producing uniform reduction. The number of but this can be adjusted by easily-set stop collars. blows per minute is approximately equal to 0·6 x r.p.m. x number of rollers. Wedges are connected to their anchorages on the wedge rod without the use of fastenings, so that they There are many areas of the machine shop where may be quickly lifted out and replaced when changing contoured, tapered and other such parts are machined by metal cutting, but if an investigation were made it a set-up. would be found more economical to form them by The performance of Torrington rotary swaging rotary swaging. machines can be considerably enhanced by the type of attachment used for work feeding. A number of The most obvious saving is through the chipless Torrington feeding attachments is available which are method of machining. A swaged part is a hammered also suitable for other applications. They range from part with no waste of material unless end trimming is required. It is clearly uneconomical to expend valuable simple manual equipment to automatic power as­ man hours in manufacturing swarf from expensive sisted models. The front surfaces of the head and base raw materials for the benefit of the scrap merchant. can accommodate a variety of feed attachments with­ out further machining. In contrast to metal cutting, swaging improves the A manual rack-and-pinion model gives sufficient tensile strength and surface hardness of the material mechanical advantage to permit the operator to feed being formed. These changes in physical properties are caused by the flow of the material under the forg­ against steep tapers. Several types of work-holders are ing hammer blows which allows the grain to follow A modern welded fabrication is used for the main available and accurate work alignment is assured. the contour of the form rather than being severed, as structure. Cast-iron was discarded as unsatisfactory Hydraulically-powered models can provide for fully in metalcutting. Furthermore, the material is subjected many years ago, and the present design has been or semi-automatic operation. Work-loading can be to pressure which densifies the surface. Substantial evolved by a company with perhaps the largest con­ manual or automatic and the feed and return cycle improvements are obtained with both ferrous and non- tinuous experience of rotary swaging. can be accurately adjusted to meet all work require­ ferrous materials. Stainless and alloy steels exhibit The head is flame cut from a solid 0·4 carbon steel ments by means of stops and electrical trips. In some these qualities to a greater degree than other metals. billet which provides maximum resistance to fracture models the required cycle may be set up with selector Carbon steels show an increase in tensile strength through strain and metal fatigue. switches on the control panel. of approximately 1,000 lb./sq. in. for each 10 percent All working parts are manufactured from the finest Die-closing machines, which are usually employed reduction in area. grade tool steel, specially hardened and finished, and for short work-pieces, can be supplied with a semi­ easily replaceable hardened-steel wear plates are In addition to increasing surface hardness, the sur­ automatic hydraulic feed. Loading and unloading are located at all friction points. Krupp bearing-quality accomplished manually, but the remainder of the face finish is improved due to a certain degree of steel is used for the inside ring to ensure long working cycle, including clamping, is completely automatic. burnishing that occurs. As a result, the finish work­ life. However, should the ring ever require replace­ The feed cycle is interlocked with the movements of piccc is free from the surface imperfections that are often exhibited by other methods of machining. ment, it can be quickly and easily pressed out of the the wedge-rod which is also automatic. Fast approach Following on this property of swaging, it is found that removable head, and a new one pressed in. and return motions are employed to reduce idle time plated parts may often be swaged without damaging The hollow spindle is driven through a substantial to a minimum. the plating. flywheel which is taper-mounted between the support Roll feeds are available for continuous through- bearings. Impact loads are therefore more evenly Consistent feeding and proper die maintenance can feeding of stock. They may be used either in pairs, one distributed which leads to greatly extended bearing usually result in tolerances of ±0·001 in. and better. at the front and one at the back, or single at the front In many applications, the piece as swaged meets life. or at the back of the machine. Loading is manual or tolerances appropriate for ground parts. Swaged parts The flywheel is easily accessible from the front of the from a magazine. When units are used in pairs, their do not require additional finishing operations to hold machine for hand rotation during machine setting. speeds can, if necessary, be adjusted relative to one close diametrical tolerances or high surface finishes. All bearings are high-quality tapered roller bearings another to compensate for the increased rate at which capable of withstanding both axial and radial thrusts. the reduced diameter work emerges from the machine. Besides being one of the most rapid methods of Aircraft Engineering

Journal

Aircraft Engineering and Aerospace Technology – Emerald Publishing

Published: Feb 1, 1964

There are no references for this article.