219:. With the high pressure process the tube is fully enclosed in a die prior to pressurization of the tube. In low pressure the tube is slightly pressurized to a fixed volume during the closing of the die (this used to be called the Variform process). Historically, the process was patented in the '50s, but it was industrially spread in the 1970s for the production of large T-shaped joints for the oil and gas industry. Today it is mostly used in the automotive sector, where many industrial applications can be found. With the rise of the electric bicycle it is now a method of choice for e-bicycle manufacturers. Especially down tubes and top tubes are favorably made with hydroforming in order to fit the battery for the electric bicycle. Newest applications in the bicycle industry are now hydroformed handlebars to improve aero dynamics and ergonomics. In tube hydroforming pressure is applied to the inside of a tube that is held by dies with the desired cross sections and forms. When the dies are closed, the tube ends are sealed by axial punches and the tube is filled with
262:
for large panels and thick hard materials. Small concave corner radii are difficult to be completely calibrated, i.e. filled, because too large a pressure would be required. in fact, the die closing force can be very high, both in tube and sheet hydroforming and may easily overcome the maximum tonnage of the forming press. In order to keep the die closing force under prescribed limits, the maximum internal fluid pressure must be limited. This reduces the calibration abilities of the process, i.e. it reduces the possibility of forming parts with small concave radii. Limits of the sheet hydroforming process are due to risks of excessive thinning, fracture, wrinkling and are strictly related to the material formability and to a proper selection of process parameters (e.g. hydraulic pressure vs. time curve). Tube hydroforming can produce many geometric options as well, reducing the need for tube welding operations. Similar limitations and risks can be listed as in sheet hydroforming; however, the maximum closing force is seldom a limiting factor in tube hydroforming.
232:
sequentially along the length of the tube, with the tube being bent around bending discs (or dies) as the tube length is fed in. Bending can be done with or without mandrels. This additional complexity of process further increases the reliance on FEM for designing and evaluating manufacturing processes. The feasibility of a hydroforming process must take into consideration the initial tube material properties and its potential for variation, along with the bending process, hydraulic pressure throughout the forming process, in inclusion of axial feed or not, in order to predict metal formability.
223:. The internal pressure can go up to a few thousand bars and it causes the tube to calibrate against the dies. The fluid is injected into the tube through one of the two axial punches. Axial punches are movable and their action is required to provide axial compression and to feed material towards the center of the bulging tube. Transverse counterpunches may also be incorporated in the forming die in order to form protrusions with small diameter/length ratio. Transverse counter punches may also be used to punch holes in the work piece at the end of the forming process.
275:
geometries. Tube
Hydroformed sections by the nature of their closed sections are very rigid and do not display high degrees of elastic deformation under load. For this reason it is likely that negative residual stress induced during tube hydroforming might be insufficient to deform the part elastically after the completion of forming. However, as more and more tubular parts are being manufactured using high strength steel and advanced high strength steel parts, springback must be accounted for in the design and manufacture of closed section tube hydroformed parts.
133:) or with a female solid die. In hydro-mechanical deep drawing, a work piece is placed on a draw ring (blank holder) over a male punch then a hydraulic chamber surrounds the work piece and a relatively low initial pressure seats the work piece against the punch. The punch then is raised into the hydraulic chamber and pressure is increased to as high as 100 MPa (15000 psi) which forms the part around the punch. Then the pressure is released and punch retracted, hydraulic chamber lifted, and the process is complete.
236:
129:
that contains the liquid; no liquid contacts the sheet) and hydroforming where the fluid contacts the sheet (no bladder). Bladder forming is sometimes called flexforming. Flexforming is mostly used for low volume productions, as in the aerospace field. Forming with the fluid in direct contact with the part can be done either with a male solid punch (this version is sometimes called hydro-mechanical
270:
Hydroforming is capable of producing parts within tight tolerances including aircraft tolerances where a common tolerance for sheet metal parts is within 0.76 mm (1/30th of an inch). Metal hydroforming also allows for a smoother finish as draw marks produced by the traditional method of pressing
252:
or male die is required. Depending on the part being formed, the punch can be made from epoxy, rather than metal. The bladder of the hydroform itself acts as the female die eliminating the need to fabricate it. This allows for changes in material thickness to be made with usually no necessary changes
128:
in the United States. It was originally used in producing kitchen spouts. This was done because in addition to the strengthening of the metal, hydromolding also produced less "grainy" parts, allowing for easier metal finishing. In sheet hydroforming there are bladder forming (where there is a bladder
261:
Another advantage of hydroforming is that complex shapes can be made in one step. In sheet hydroforming with the bladder acting as the male die almost limitless geometries can be produced. However, the process is limited by the very high closing force required in order to seal the dies, especially
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While springback has long been a topic of discussion for sheet metal forming operations it has been far less of a topic of research for tube hydroforming. This may in part be a result of the relatively low levels of springback naturally occurring when deforming the tubes into their closed section
85:
working material into a die. To hydroform aluminium into a vehicle's frame rail, a hollow tube of aluminium is placed inside a negative mold that has the shape of the desired result. High pressure hydraulic pumps then inject fluid at very high pressure inside the aluminium tube which causes it to
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simulations must be performed in order to find a feasible process solution and to define the correct loading curves: pressure vs. time and axial feed vs. time. In the case of more complex tube hydroformed parts the tube must be pre-bent prior to loading into the hydroforming die. Bending is done
194:
For large parts, explosive hydroforming can generate the forming pressure by simply exploding a charge above the part (complete with evacuated mold) which is immersed in a pool of water. The tooling can be much cheaper than what would be required for any press-type process. The
226:
Designing the process has in the past been a challenging task, since initial analytical modeling is possible only for limited cases. Advances in FEA and FEM in recent years has enabled hydroform processes to be more widely engineered for varieties of parts and materials. Often
31:
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into lightweight, structurally stiff and strong pieces. One of the largest applications of cost-effective hydroforming is the automotive industry, which makes use of the complex shapes made possible by hydroforming to produce stronger, lighter, and more rigid
140:
of sheet material by distinctive stretching operations and provides better shape accuracy for complex parts. Hence, by selecting proper material and the forming parameters for hydraulic sheet bulging study one can determine
Forming Limit Curves (FLCs).
150:
Hydraulic bulge testing is more appropriate for sheet metal forming operations as deformation mode is bi-axial rather than uniaxial. Also it provides flow curves for the materials with extended range of plastic strain levels up to 70% before bursting
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The use of only single form surface tooling, which saves time and expense in the manufacture of tooling. Absence of rigid tool contact on one surface also reduces surface friction and thus surface defects, resulting in a good surface
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expand until it matches the mold. The hydroformed aluminium is then removed from the mold. Hydroforming allows complex shapes with concavities to be formed, which would be difficult or impossible with standard
154:
It is helpful to generate the FLCs which will be reliable sense of reference input to the explicit solver like LS-DYNA. These obtained FLCs are used as load curve input for such solvers for analysis.
160:
Hydraulic bulge testing would be helpful to calculate the Strain hardening coefficient- "n" (i.e. Work hardening coefficient) of the material, to determine the ability of the material to be formed.
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Many motor vehicles have components manufactured using hydroformed tubing, with the first mass-produced automotive component being the instrument panel support beam for the 1990 Chrysler
Minivan.
359:
The process has recently become popular for the manufacture of aluminium wheelchair frames and wheelchair hand rims, making wheelchair more rigid and lightweight and hand rims more ergonomic.
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The technique is widely used in the manufacture of engine cradles. The first mass-produced one was for the Ford
Contour and Mystique in 1994. Others from a long list include the
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FLCs also serve the best for identifying the exact zone for forming operations without getting affected with localized necking and other possible defects while forming.
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Tools and punches can be interchanged for different part requirements. One advantage of hydroforming is the savings on tools. For sheet metal only a draw ring and
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hydroforming-into-a-mold process also works using only a shock wave in air as the pressuring medium. Particularly when the explosives are close to the workpiece,
593:
Hydroforming technology. (conference report): Advanced
Materials & Processes (Refereed) : May 1, 1997: ASM International: v151 : n5 : p50(4)
467:
Hatipoğlu, H. Ali; Polat, Naki; Köksal, Arif; Tekkaya, A.Erman (1 January 2007). "Modeling
Flexforming (Fluid Cell Forming) Process with Finite Element Method".
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A controlled pressure distribution over part surface during forming can be used to “control” the sheet thickness and postpone localized necking.
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The process has become popular for the manufacture of aluminium bicycle frames. The earliest commercially manufactured one being that of the
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to the tool. However, dies must be highly polished and in tube hydroforming a two-piece die is required to allow opening and closing.
1000:
969:
630:
Strano, Matteo; Jirathearanat, Suwat; Shr, Shiuan-Guang; Altan, Taylan (2004). "Virtual process development in tube hydroforming".
702:. 5th International symposium on reducing the cost of spacecraft ground systems and operations. Pasadena, CA: NASA. Archived from
216:
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This process is based on the 1950s patent for hydramolding by Fred
Leuthesser, Jr. and John Fox of the Schaible Company of
1028:
962:
914:"Evaluation of Two Wheelchair Hand Rim Models: Contact Pressure Distribution in Straight Line and Curve Trajectories"
807:
502:
Strano, M (2006). "Optimization under uncertainty of sheet-metal-forming processes by the finite element method".
91:
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Other significant automotive applications for hydroforming include suspension components, and radiator supports.
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334:. A selection from many examples are the current versions of the three major United States pickup trucks—the
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Proceedings of the
Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture
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Dachang, Kang; Yu, Chen; Yongchao, Xu (2005). "Hydromechanical deep drawing of superalloy cups".
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industry and is also frequently employed in the shaping of aluminium tubes for bicycle frames.
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uses electrodes to vaporize the fluid explosively in an arc to deform the working material.
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Hydroforming for advanced manufacturing, Ed. by M, Koç, 2009 Woodhead
Publishing Limited
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can be hydroformed, including aluminium, brass, carbon and stainless steel, copper, and
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than traditional stamped or stamped and welded parts. Virtually all metals capable of
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effects make the result more complicated than forming by hydrostatic pressure alone.
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structures for vehicles. This technique is particularly popular with the high-end
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Various vehicle frame components, the earliest mass-produced one being the 1997
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Among these techniques hydraulic bulge testing allows for an increased
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Process sequence in tube hydroforming of a t-shape with counterpunch
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Asnafi, Nader (1999). "Analytical modelling of tube hydroforming".
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Low cost microwave ground terminals for space communication
864:"2006 Pontiac Solstice Sheetmetal Hydroforming Technology"
912:
Silva, D. C.; Paschoarelli, L. C.; Medola, F. O. (2019).
784:"Tier 1 supplier builds four-stage competitive strategy"
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Alternative names, other variants and similar processes
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In tube hydroforming there are two major practices:
90:. Hydroformed parts can often be made with a higher
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27:Method of shaping metal through pressurized water
271:a male and female die together are eliminated.
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346:—which all have hydroformed frame rails, 2006
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888:"Utility Vehicle has hydroformed steel frame"
8:
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632:Journal of Materials Processing Technology
539:Journal of Materials Processing Technology
759:"2001 Pontiac Aztek - First Drive Review"
34:A plate being shaped through hydroforming
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180:Hydromec (Hydromechanical deep drawing)
481:10.4028/www.scientific.net/KEM.344.469
366:Revive bicycle first marketed in 2003.
299:Lighting fixture housing and reflector
73:Hydroforming is a specialized type of
7:
841:. 13 September 2004. Archived from
808:"2009 Harley Davidson V-Rod Muscle"
320:and the perimeter frame around the
693:Weinreb, Sander (8–11 July 2003).
77:forming that uses a high pressure
25:
551:10.1016/j.jmatprotec.2004.08.024
322:Harley Davidson V-Rod motorcycle
163:A simple and versatile approach.
350:and the steel frame inside the
217:high pressure and low pressure
41:is a means of shaping ductile
1:
930:10.1080/00140139.2019.1660000
673:"Great Designs in Steel 2015"
644:10.1016/S0924-0136(03)00853-7
617:10.1016/S0263-8231(99)00018-X
266:Tolerances and surface finish
782:Eric Lundin (24 July 2003).
733:Fundamentals of Hydroforming
835:"Hydroformed Frame Repairs"
1343:
410:"The Hydroforming Process"
354:HPX Gator Utility Vehicle.
283:Notable examples include:
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469:Key Engineering Materials
92:stiffness-to-weight ratio
1086:Electrohydraulic forming
730:Harjinder Singh (2003).
671:Hertell (May 11, 2015).
109:Electrohydraulic forming
1091:Electromagnetic forming
757:Tony Swan (July 2000).
1076:Casting (metalworking)
839:I-Car Advantage Online
605:Thin-Walled Structures
516:10.1243/09544054JEM480
240:
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1297:Tools and terminology
455:U.S. patent 2,713,314
294:Allen Telescope Array
238:
115:Main process variants
104:high strength alloys.
33:
1126:Progressive stamping
414:Jones Metal Products
250:punch (metalworking)
1202:Finishing processes
364:Giant Manufacturing
340:Chevrolet Silverado
287:Sheet Hydro Forming
94:and at a lower per
845:on 21 October 2012
736:. SME. p. 4.
565:"first thf patent"
369:The brass tube of
332:Chevrolet Corvette
304:Tube Hydro Forming
241:
205:Rubber pad forming
120:Sheet hydroforming
88:solid die stamping
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1165:Joining processes
1096:Explosive forming
1064:Forming processes
924:(12): 1563–1571.
894:. 5 December 2003
812:thekneeslider.com
743:978-0-87263-662-0
434:"first HF patent"
257:Geometry produced
211:Tube hydroforming
190:Explosive forming
16:(Redirected from
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1156:Tube bending
1111:Hydroforming
1110:
986:Metalworking
921:
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907:
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843:the original
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387:Blow molding
318:Honda Accord
282:
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131:deep drawing
123:
107:
100:cold forming
72:
53:, low alloy
39:Hydroforming
38:
37:
1267:Fabrication
1215:Galvanizing
1055:Sheet metal
1045:Fabrication
1029:fabrication
475:: 469–476.
18:Hydroformed
1287:Metallurgy
1230:Patination
1050:Piece work
918:Ergonomics
898:2008-12-05
873:2008-12-05
849:2008-12-05
817:2008-12-05
793:2008-12-05
768:2008-12-05
713:2008-11-21
419:2011-06-21
397:References
374:saxophones
352:John Deere
336:Ford F-150
324:'s engine.
68:sports car
1282:Machining
1277:Jewellery
1245:Polishing
1210:Anodizing
1187:Soldering
1101:Extrusion
946:201748187
892:ThomasNet
524:108843522
489:137151717
96:unit cost
81:to press
47:aluminium
1321:Category
1292:Smithing
1182:Riveting
1177:Crimping
1146:Spinning
1131:Punching
1116:Stamping
938:31446854
381:See also
279:Examples
183:Aquadraw
45:such as
1302:Welding
1272:Forming
1262:Casting
1240:Plating
1235:Peening
1192:Welding
1172:Brazing
1151:Swaging
1141:Sinking
1136:Rolling
1106:Forging
1081:Drawing
1071:Coining
1038:General
1025:Forming
570:17 July
439:17 July
197:inertia
170:finish.
151:occurs.
64:unibody
944:
936:
740:
522:
487:
389:, for
371:Yamaha
342:, and
316:, the
57:, and
43:metals
942:S2CID
707:(PDF)
700:(PDF)
676:(PDF)
520:S2CID
485:S2CID
55:steel
51:brass
934:PMID
738:ISBN
572:2012
441:2012
926:doi
640:doi
636:146
613:doi
547:doi
543:166
512:doi
508:220
477:doi
473:344
344:Ram
229:FEM
75:die
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