The present disclosure is generally related to material forging and, more particularly, to an apparatus and method for momentum-balanced forging.
Various forging methods are known for shaping metal using localized compressive forces. Forging machines may utilize a very heavy hammer that travels along a linear path towards a very heavy anvil. A workpiece is placed upon the anvil and the hammer delivers an impact force to deform the workpiece. The forging hammer derives its power from the kinetic energy of the hammer in motion.
The mass of the hammer or the pressure applied to the hammer is an important factor in the forging process. Forging hammers typically may weigh between several hundred to several thousand pounds. Forging anvils must provide a solid base and may weigh up to thirty times the weight of the forging hammer.
Unfortunately, the large masses or pressures required for forging may result in the transmission of impact loads and vibrations to the forging machine frame and/or the floor. These loads may damage the floor or the machine frame and may impact the effectiveness of the forging process. As a result, forging machines require damper systems attached to the base of the forging machine to absorb and/or dissipate the impact loads and other energy resulting from the impact of the forging hammer.
Accordingly, those skilled in the art continue with research and development efforts in the field of material forging.
In one embodiment, the disclosed apparatus for forging may include a machine frame, a first tooling member connected to the machine frame, the first tooling member being moveable relative to the machine frame, and a second tooling member connected to the machine frame opposite the first tooling member, the second tooling member being moveable relative to the machine frame, wherein the first tooling member and the second tooling member are configured to impact a workpiece positioned between the first tooling member and the second tooling member, and wherein the net momentum of the first and second tooling members is minimized.
In another embodiment, the disclosed apparatus for forging may include a moveable first tooling member configured to form a workpiece upon impact with the workpiece, a moveable second tooling member configured to form the workpiece upon impact with the workpiece, wherein the first tooling member and the second tooling member are each moveable relative to one another, and wherein a net momentum of a simultaneous impact with the workpiece by the first tooling member and the second tooling member is minimized (e.g., approximately zero).
In another embodiment, also disclosed is a method for forging, the method may include the steps of: (1) providing a workpiece to be formed, (2) providing a moveable first tooling member configured to form the workpiece upon impact with the workpiece and a moveable second tooling member configured to form the workpiece upon impact with the workpiece, the first tooling member and the second tooling member each being moveable relative to one another, (3) balancing a momentum of the first tooling member and the second tooling member such that a net momentum of a simultaneous impact with the workpiece by the first tooling member and the second tooling member is minimized (e.g., approximately zero), and (4) forming the workpiece in response to an impact force generated by the simultaneous impact with the workpiece by the first tooling member and the second tooling member.
Other embodiments of the disclosed apparatus and method for forging will become apparent from the following detailed description, the accompanying drawings and the appended claims.
The following detailed description refers to the accompanying drawings, which illustrate specific embodiments of the disclosure. Other embodiments having different structures and operations do not depart from the scope of the present disclosure. Like reference numerals may refer to the same element or component in the different drawings.
Referring to
The first tooling member 14 and the second tooling member 16 may be aligned (e.g., along a longitudinal axis A of the machine frame 12) and opposed to one another such that an impact force FI (
The workpiece 32 may be any formable or semi-formable material. For example the workpiece 32 may be a metallic material (e.g., a metal blank, a metal slug, metal billet, metal ingot, metal bloom, metal slab, or other metal workpiece). As another example, the workpiece 32 may be a non-metallic material (e.g., plastic, composite, or the like). The forging operation may be performed on a hot workpiece 32 (e.g., hot forging or hot working) or on a cold workpiece 32 (e.g., cold working or cold forging).
The machine frame 12 may support a first (e.g., lower) driving mechanism 26 and a second (e.g., upper) driving mechanism 28. The first driving mechanism 26 may be configured to move the first tooling member 14 toward the second tooling member 16 (e.g., upwardly). The second driving mechanism 28 may be configured to move the second tooling member 16 toward the first tooling member 14 (e.g., downwardly).
The machine frame 12 may include various structural components suitable to support the first tooling member 14, the first driving mechanism 26, the second tooling member 16, and the second driving mechanism 28 during a forging process. In one example construction, the machine frame 12 may include one or more substantially vertical frame members. For example, a pair of vertical frame members 18 and 20 may be disposed symmetrically with respect to a longitudinal axis A of the machine frame 12. The frame member 18, 20 may provide a guide (e.g., a linear guide) for motion of the first tooling member 14 and the second tooling member 16. In another example construction, the machine frame 12 may include horizontal frame members that facilitate movement of the first and second tooling members 14, 16 is a substantially horizontal direction.
Lower ends of the frame members 18, 20 may be rigidly connected to a base member 22. The first driving mechanism 26 may be housed within, connected to, or supported by the base member 22. The first drive mechanism 26 may be operably connected to the first tooling member 14. The base member 22 may be supported by a work surface 24 (e.g., factory floor). The base member 22 may be connected to the work surface 24 by any suitable connector or fastener mechanism.
Upper ends of the frame members 18, 20 may be rigidly connected to a cross member 23. The second driving mechanism 28 may be housed within, connected to, to supported by the cross member 23. The second drive mechanism 26 may be operably connected to the second tooling member 16.
The frame members 18, 20 may be made of any suitable rigid and durable material. However, as explained in more detail below, due to the near zero net momentum produced by the impact of the first tooling member 14 and the second tooling member 16, the structural components of the machine frame 12 may be constructed of considerably lighter weight materials than traditional heavy hammer forging machines.
During the forging process, the workpiece 32 may be positioned at the impact zone 30. The first tooling member 14 may be driven toward the impact zone 30 and the second tooling member 16. The second tooling member 16 may be driven toward the impact zone 30 and the first tooling member 14. Upon impact of the first tooling member 14 and the second tooling member 16 with the workpiece 32, the impact force FI (
Referring to
The first tooling member 14 may begin at a first initial position P11. The drive stroke of the first tooling member 14 may include movement from the first initial position P11, through a first impact position P12, and to a first final position P13 (
The impact positions P12, P22 may be the respective locations of the tooling members 14, 16 at the instant of impact with the workpiece 32 (e.g., immediate before impact). The final positions P13, P23 (
The return stroke of the first tooling member 14 may include movement from the first final position P13 (
The first tooling member 14 may translate between the first initial position P11 and the first final position P13 (e.g., along the longitudinal axis A (
The distance between the impact position P12 and the final position P13 of the first tooling member 14 and the impact position P22 and the final position P23 of the second tooling member 16 may define the impact zone 30. The impact zone 30 may be the location where work is performed on the workpiece 32 by the transfer of kinetic energy from the first tooling member 14 and the second tooling member 16 to the workpiece 32.
Still referring to
The second tooling member 16 and any components that move with the second tooling member 16 may include a second mass M2. The second driving mechanism 28 may apply a second force F2 to move the second tooling member 16 and any components that move with the second tooling member 16 (e.g., the second mass M2). The second tooling member 16 may have a second initial velocity V21 (
The first tooling member 14 may begin at rest (e.g., where the initial velocity V11 is zero at the initial position P11). The first tooling member 14 may move a first distance D1 between the initial position P11 and the impact position P12. The first force F1 may be suitable for the first tooling member 14 to achieve the impact velocity V12 at the impact position P12. Upon impact, the first tooling member 14 may move a first distance d1 between the impact position P12 and the final position P13 deforming the workpiece 32.
The second tooling member 16 may begin at rest (e.g., where the initial velocity V21 is zero at the initial position P21). The second tooling member 16 may move a second distance D2 between the initial position P21 and the impact position P22. The second force F2 may be suitable for the second tooling member 16 to achieve the impact velocity V22 at the impact position P22. Upon impact, the second tooling member 16 may move a second distance d2 between the impact position P22 and the final position P23 deforming the workpiece 32.
The momentum of each of the first tooling member 14 and the second tooling member 16 may be determined by the following equation:
P=MV (Eqn. 1)
wherein, P is the momentum of an object, M is the mass of the tooling member and any components that move with the tooling member, and V is the velocity of the tooling member and any components that move with the tooling member.
Thus, the equation for balanced-momentum at the instant of impact (e.g., the first tooling member 14 at the first impact position P12 and the second tooling member 16 at the second impact position P22) is:
M1V12=M2V22 (Eqn. 2)
wherein, M1 is the mass of the first tooling member 14 and any components that move with the first tooling member 14, V12 is the impact velocity of the first tooling member 14 and any components that move with the first tooling member 14 at the impact position P12, M2 is the mass of the second tooling member 16 and any components that move with the second tooling member 16, and V22 is the impact velocity of the second tooling member 16 and any components that move with the second tooling member 16 at the impact position P22.
Momentum balancing of the first tooling member 14 and the second tooling member 16 at the instant of impact may allow for a significantly less robust machine frame 12. Further momentum balancing may reduce (if not eliminate) any loads and/or vibrations applied to the machine frame 12 and/or the work surface 24 as a result of the impact between the first tooling member 14 and the second tooling member 16 upon the workpiece 32 thus, reducing (if not eliminating) the need for damper systems connected between the machine frame 12 and the work surface 24.
At this point, those skilled in the art will appreciate that loads and/or vibrations may be minimized by zeroing the net momentum (|M1V12|−|M2V22|=0). However, advantage may still be gained by minimizing the net momentum, albeit not to zero. In one expression, the net momentum may be minimized by configuring the momentum (M1V12) of the first tooling member 14 at the first impact position P12 to be within 20 percent of the momentum (M2V22) of the second tooling member 16 at the second impact position P22. In another expression, the net momentum may be minimized by configuring the momentum (M1V12) of the first tooling member 14 at the first impact position P12 to be within 10 percent of the momentum (M2V22) of the second tooling member 16 at the second impact position P22. In yet another expression, the net momentum may be minimized by configuring the momentum (M1V12) of the first tooling member 14 at the first impact position P12 to be within 5 percent of the momentum (M2V22) of the second tooling member 16 at the second impact position P22.
The first tooling member 14 may be configured for operation with the design specifications of the apparatus for forging 10 and the workpiece 32. The first tooling member 14 may be suitably sized (e.g., dimensions and mass) to adequately support the size of the workpiece 32 (e.g., dimensions and mass). The apparatus for forging 10 may be designed based at least in part by the impact force FI (e.g., compression force) required to deform the workpiece 32 (e.g., create the desired geometric change to the material of the workpiece).
In an example construction, the first tooling member 14 may include a heavy member (e.g., having a large mass M1 relative to the mass M2 of the second tooling member 16) and may move at a relatively slow velocity (e.g., an impact velocity V12 significantly less than the impact velocity V22 of the second tooling member 16). The second tooling member 16 may include a relatively light member (e.g., having a small mass M2 relative to the mass M1 of the first tooling member 14) and may move at a very high velocity (e.g., an impact velocity V22 significantly greater than the impact velocity V12 of the first tooling member 14). As described above, the apparatus for forging 10 may be configured such that the first mass M1 at impact velocity V12 is equal to the second mass M2 at impact velocity V22 such that the momentum P at the instant of impact is balanced.
For example, the second mass M2 of the second tooling member 16 may be between approximately 20 percent and 50 percent of the first mass M1 of the first tooling member 14 and the impact velocity V12 of the first tooling member 14 may be between approximately 20 percent and 50 percent of the impact velocity V22 of the second tooling member 16.
As another example, the second mass M2 of the second tooling member 16 may be between approximately 10 percent and 20 percent of the first mass M1 of the first tooling member 14 and the impact velocity V21 of the first tooling member 14 may be between approximately 10 percent and 20 percent of the impact velocity V22 of the second tooling member 16.
As another example, the second mass M2 of the second tooling member 16 may be between approximately 5 percent and 10 percent of the first mass M1 of the first tooling member 14 and the impact velocity V21 of the first tooling member 14 may be between approximately 5 percent and 10 percent of the impact velocity V22 of the second tooling member 16.
As another example, the second mass M2 of the second tooling member 16 may be less than 5 percent of the first mass M1 of the first tooling member 14 and the impact velocity V21 of the first tooling member 14 may be less than 5 percent of the impact velocity V22 of the second tooling member 16.
As a specific non-limiting example, the first tooling member 14 may have a weight of 50 lbs. (mass M1 of 22.68 kg) and an impact velocity V12 of 30 ft/s (9.14 m/s). The second tooling member 16 may have a weight of 5 lbs. (mass M2 of 2.268 kg) and an impact velocity V22 of 300 ft/s (91.44 m/s).
As another specific non-limiting example, the first tooling member 14 may have a weight of 500 lbs. (mass M1 226.8 kg) and an impact velocity V12 of 10 ft/s (3.05 m/s). The second tooling member 16 may have a weight of 50 lbs. (mass M2 22.68 kg) and an impact velocity V22 of 100 ft/s (30.48 m/s).
Referring again to
In an example implementation, as illustrated in
In another example implementation, the workpiece 32 may be held in position at the impact zone 30. The workpiece 32 may be held in place by an external holding fixture (not shown). For example, the holding fixture may include an operator, a machine, or any other suitable holding fixture without limitation. Thus, the first mass M1 of the first tooling member 14 may include only the mass of the first die 36. Upon impact of the first die 36 and the second die 38 with the workpiece 32, the impact force FI may deform the workpiece 32 into a fully or partially forged part 34.
Referring to
The first bolster plate 50 may be connected to secondary mass 60 of the first tooling member 14 (e.g., an anvil) that is operably connected directly to the first driving mechanism 26. Alternatively, the first bolster plate 50 may be operably connected directly to the first driving mechanism 26.
The second tooling member 16 may include a second die 52 (e.g., a mold). The second die 52 may include a second die surface 54 that defines at least one second cavity 56. The second tooling member 16 may include a second bolster plate 58 configured to securely hold the second die 52. The second die 52 may be rigidly connected (e.g., removably) or affixed (e.g., integrally) to the second bolster plate 58. For example, the second die 52 may be connected to the second bolster plate 58 by one or more mechanical fasteners (not shown). The fasteners may include any suitable mechanism configured to securely connect the second die 52 to the second bolster plate 58 including, but not limited to, bolts, clamps, brackets, pins, rails, or any other fastening means.
The second bolster plate 58 may be connected to secondary mass 62 of the second tooling member 16 (e.g., a hammer) that is operably connected directly to the second driving mechanism 28. Alternatively, the second bolster plate 58 may be operably connected directly to the second driving mechanism 28.
Optionally, the frame members 18, 20 may include a pair of linear guides 64, 66, respectively. A portion of the first tooling member 14 and/or the second tooling member 16 may engage the guides 64, 66 during the drive stroke and the return stroke. For example, the first bolster plate 50 and the second bolster plate 58 may each include channels configured to engage the guides 64, 66.
In an example implementation, as illustrated in
In another example implementation, the workpiece 32 may be held in position at the impact zone 30. The workpiece 32 may be held in pace by an external holding fixture (not shown). For example, the holding fixture may include an operator, a machine, or any other suitable holding fixture without limitation. Thus, the first mass M1 of the first tooling member 14 may include the mass of the first die 44, the mass of the first bolster plate 50, and optionally the mass of the secondary mass 60. Upon impact of the first die 44 and the second die 52 with the workpiece 32, the impact force FI may deform the workpiece 32 into a fully or partially forged part 34.
Those skilled in the art will appreciate that the first driving mechanism 26 and the second driving mechanism 28 may include any driving mechanism suitable to provide the respective driving forces F1 and F2 required to move the first tooling member 14 and the second tooling member 16 at respective impact velocities V12, V22 to achieve momentum balance. For example, the drive mechanisms 26, 28 may include, but are not limited to, mechanical drive mechanisms, pneumatic drive mechanisms, hydraulic drive mechanisms, combustion drive mechanisms, electromagnetic drive mechanisms, and the like.
Those skilled in the art will appreciate that the drive mechanisms 26, 28 may include various structural components configured to move (e.g., linearly) the tooling members 14, 16, respectively, through the drive stroke and/or the return stroke. For example, each of the drive mechanisms 26, 28 may include a pneumatic cylinder, a hydraulic cylinder, a combustion cylinder, or a motor configured to linearly translate the tooling members 14, 16. The drive mechanisms 26, 28 may include various other components, including, but not limited to, pumps, pistons, rods, valves, fittings, igniters, crankshafts and the like configured to apply the first force F1 and the second force F2 to the first tooling member 14 and the second tooling member 16, respectively.
In certain example constructions, depending upon the type of driving mechanism 26, 28 utilized, the apparatus for forging 10 may include one or more return mechanisms (not shown). The return mechanism may be connected between the machine frame 12 and the tooling member 14, 16. The return mechanism may be configured to return the tooling members 14, 16 back to the initial position P11, P21, respectively.
In an example implementation, the first drive mechanism 26 and the second drive mechanism 28 may be substantially the same type of drive mechanism. In another example implementation, the first drive mechanism 26 and the second drive mechanism 28 may be different types of drive mechanisms.
Referring to
Each driving mechanism 26, 28 may share a single energy source 68 or each driving mechanism 26, 28 may be connected to its own energy source 68. For example, if the first drive mechanism 26 and the second drive mechanism 28 are substantially the same type of drive mechanism, each driving mechanism 26, 28 may share a single energy source 68. As another example, if the first drive mechanism 26 and the second drive mechanism 28 are different types of drive mechanisms, each driving mechanism 26, 28 may be connected to its own energy source 68.
The apparatus for forging 10 may include a controller 70. The controller 70 may be configured to control the impact velocities V12, V22 of the tooling members 14, 16, respectively. For example, the controller 70 may adjust the driving forces F1, F2 applied to the tooling members 14, 16 by the driving mechanisms 26, 28.
The impact velocities V12, V22 of one or both of the tooling members 14, 16 and thus, the driving forces F1, F2 generated by one or both of the driving mechanisms 26, 28 may require adjustment based on changes to the forging operation. For example, if the mass M1, M2 of one or both of the tooling members 14, 16 changes, the driving forces F1, F2 required may need to be adjusted in order to achieve the impact velocities V12, V22 needed to generate the required impact force FI for desired deformation of the workpiece 32 and maintain a momentum-balanced system.
One or more sensors 72 may be configured to detect one or more operating conditions of the apparatus for forging 10 and/or the forging process. For example, sensors 72 may detect the velocity of the tooling members 14, 16 (e.g., at the impact position P21, P22). As another example, sensors 72 may detect the position of the tooling members 14, 16 throughout the drive stroke and the return stroke. As another example, sensors 72 may detect the magnitude of the impact force FI. As another example, sensors 72 may detect the magnitude of the driving forces F1, F2.
The sensors 72 may be connected to the controller 70. The controller 70 may adjust various operating conditions based upon input provided from the sensors 72. The controller 70 may be automatically controlled by one or more computers implementing computer code or may be manually controlled by an operator.
The resulting impact force FI generated by the impact of the first tooling member 14 and the second tooling member 16 upon the workpiece 32 may have a magnitude sufficient to deform the workpiece 32 as desired. The impact force FI may depend on several factors including, but not limited to, the material composition of the workpiece 32, the size of the workpiece 32, the volume of the workpiece 32, the desired deformation (e.g., the change in height and/or width) of the workpiece 32, among other things. For example, the impact force FI may be determined by the required change in instantaneous height of the workpiece 32 during the forging process, which may correspond to the first distance d1 of the first tooling member 14 between the impact position P12 and the final position P13 and the second distance d2 of the second tooling member 16 between the impact position P22 and the final position P23.
Those skilled in the art will appreciate that force F may be determined by the following equation:
F=ma (Eqn. 3)
wherein, m is the mass of a body and a is acceleration of the body.
Further, acceleration a may be determined by the following equation:
a=v2/2d (Eqn. 4)
wherein, v is the velocity of the body and d is the displacement of the body.
Thus, the impact force FI may be determined by the following equation:
FI=MV2/2d (Eqn. 5)
wherein, M is the mass of the tooling member and any components that move with the tooling member, V is the velocity of the tooling member and any components that move with the tooling member, and d is the distance the tooling member travels immediate after impact (e.g., distance between impact position P2 and final position P3).
The driving force F may be determined by the following equation:
F=MV2/2D (Eqn. 6)
wherein, M is the mass of the tooling member and any components that move with the tooling member, V is the velocity of the tooling member and any components that move with the tooling member, and D is the distance the tooling member travels immediate before impact (e.g., distance between initial position P1 and impact position P2).
Thus, given certain operational parameters (e.g., impact force FI, distance d1, d2, distance D1, D2, and/or mass M1, M2 of either tooling member 14, 16 and any components that move with the tooling member), other operational conditions of the apparatus for forging 10 and/or forging process may be determined (e.g., the required impact velocity V2 of either tooling member 14, 16 and any components that move with the tooling member, or the driving force F1, F2) (
Eqn. 2 may be used to determine the required mass M1, M2 of an opposed tooling member 14, 16 and any components that move with the tooling member and/or the required impact velocity V2 of an opposed tooling member 14, 16 and any components that move with the tooling member in order to maintain a momentum-balanced system and equal impact force FI.
Accordingly, use of the disclosed apparatus and method for momentum-balanced forging may allow for significantly lighter tooling members (e.g., hammer and/or anvil) while still producing substantially similar impact forces during forging of a workpiece.
Referring to
As shown at block 104, a workpiece 32 may be provided. The workpiece 32 may be any material, such as a metallic material, suitable for forming through the forging process.
As shown at block 106, the apparatus for forging 10 may be provided. The apparatus for forging 10 may include at least the moveable first tooling member 14 configured to form the workpiece 32 upon impact with the workpiece 32 and the moveable second tooling member 16 configured to form the workpiece 32 upon impact with the workpiece 32. The first tooling member 14 and the second tooling member 16 may each be moveable relative to one another (e.g., linearly along the longitudinal axis A of the machine frame 12).
As shown at block 108, a momentum of the first tooling member 14 and the second tooling member 16 may be balanced such that a net momentum of a simultaneous impact with the workpiece by the first tooling member 14 and the second tooling member 16 is minimized (e.g., approximately zero).
As shown at block 110, the workpiece 32 may be formed into a forged part 34 in response to an impact force generated by the simultaneous impact with the workpiece by the first tooling member and the second tooling member.
As shown at block 112, the impact velocities V21, V22 of the first tooling member 14 and/or the second tooling member 16, respectively, may be adjusted, such as in response to changes in travel distance due to forging, to maintain approximately zero net momentum. The impact velocities V21, V22 of the first tooling member 14 and/or the second tooling member 16, respectively, may be adjusted by modifying the first driving force F1 applied to the first tooling member 14 by the first driving mechanism 26 and/or the second driving force F2 applied to the second tooling member 16 by the second driving member 28.
Examples of the disclosure may be described in the context of an aircraft manufacturing and service method 200, as shown in
Each of the processes of method 200 may be performed or carried out by a system integrator, a third party, and/or an operator (e.g., a customer). For the purposes of this description, a system integrator may include without limitation any number of aircraft manufacturers and major-system subcontractors; a third party may include without limitation any number of venders, subcontractors, and suppliers; and an operator may be an airline, leasing company, military entity, service organization, and so on.
As shown in
The disclosed forging apparatus and method may be employed during any one or more of the stages of the production and service method 200. As one example, components or subassemblies corresponding to production process 208 may be fabricated or manufactured using the disclosed forging apparatus and method. As another example, the disclosed forging apparatus and method may be used during the maintenance and service step 216, such as to fabricate or repair components, such as components of the airframe 218 of the aircraft 202. Also, the disclosed forging apparatus and method may be utilized during the production stages 208 and 210, and/or during maintenance and service 216 to substantially expedite the process and/or to reduce overall costs.
Although various embodiments of the disclosed apparatus and method for momentum-balanced forging have been shown and described, modifications may occur to those skilled in the art upon reading the specification. The present application includes such modifications and is limited only by the scope of the claims.
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