FORGING

FIELD The present disclosure is generally related to material forging and, more particularly, to an apparatus and method for momentum-balanced forging.

BACKGROUND

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. SUMMARY

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. In summary, according to one aspect of the invention there is provided an apparatus for forging including a machine frame; a first tooling member connected to said machine frame, said first tooling member being moveable relative to said machine frame; and a second tooling member connected to said machine frame opposite said first tooling member, said second tooling member being moveable relative to said machine frame; wherein said first tooling member and said second tooling member are configured to impact a workpiece between said first tooling member and said second tooling member. Advantageously the apparatus wherein said first tooling member comprises a first mass and said second tooling member comprises a second mass; and wherein said second mass is less than said first mass.

Advantageously the apparatus wherein said second mass is between 10 percent and 20 percent of said first mass.

Advantageously the apparatus wherein said first tooling member comprises a first velocity immediately before said impact with said workpiece and said second tooling member comprises a second velocity immediately before impact with said workpiece; and wherein said first velocity is less than said second velocity.

Advantageously the apparatus wherein said first velocity is between 10 percent and 20 percent of said second velocity.

Advantageously the apparatus wherein said first tooling member comprises a first momentum immediately before said impact with said workpiece and said second tooling member comprises a second momentum immediately before said impact with said workpiece, and wherein said first momentum and said second momentum are substantially equal.

Advantageously the apparatus wherein said first tooling member comprises a first momentum immediately before said impact with said workpiece and said second tooling member comprises a second momentum immediately before said impact with said workpiece, and wherein said first momentum is within 10 percent of said second momentum.

Advantageously the apparatus wherein said first tooling member comprises a first momentum immediately before said impact with said workpiece and said second tooling member comprises a second momentum immediately before said impact with said workpiece, and wherein said first momentum is within 5 percent of said second momentum.

Advantageously the apparatus wherein said first tooling member comprises a first die and said second tooling member comprises a second die, said first die and said second die each being configured to form said workpiece.

Advantageously the apparatus further including a first driving mechanism operably connected to said first tooling member, said first driving mechanism being configured to apply a first driving force upon said first tooling member; and a second driving mechanism operably connected to said second tooling member, said second driving mechanism being configured to apply a second driving force upon said second tooling member.

Advantageously the apparatus wherein said first driving mechanism and said second driving mechanism each comprises at least one of a pneumatic drive mechanism, a hydraulic drive mechanism, a combustion drive mechanism, a mechanical drive mechanism, and an electromagnetic drive mechanism.

Advantageously the apparatus further comprising at least one energy source operably connected to said first drive mechanism and said second drive mechanism.

Advantageously the apparatus wherein said first tooling member comprises a first mass, said first driving force moves said first mass at a first velocity immediately before said impact with said workpiece; wherein said second tooling member comprises a second mass, said second driving force moves said second mass at a second velocity immediately before said impact with said workpiece; and, wherein a net momentum at said impact with said workpiece of said first mass at said first velocity and said second mass at said second velocity is approximately zero.

Advantageously the apparatus further comprising at least one controller operably connected to said first drive mechanism and said second drive mechanism; said controller being configured to adjust at least one of said first driving force and said second driving force to maintain said approximately zero net momentum.

Advantageously the apparatus wherein said first tooling member travels along a substantially linear path toward said second tooling member.

According to another aspect of the invention there is provided a n apparatus for forging including a moveable first tooling member configured to form a workpiece upon impact with said workpiece; a moveable second tooling member configured to form said workpiece upon impact with said workpiece; wherein said first tooling member and said second tooling member are each moveable relative to one another; and wherein a net momentum of a simultaneous impact with said workpiece by said first tooling member and said second tooling member is approximately zero. Advantageously the apparatus wherein said first tooling member comprises a first mass and said second tooling member comprises a second mass; and wherein said second mass is less than said first mass.

Advantageously the apparatus wherein said second mass is between 5 percent and 20 percent of said first mass.

Advantageously the apparatus wherein said first tooling member comprises a first velocity immediately before said impact with said workpiece and said second tooling member comprises a second velocity immediately before impact with said workpiece; and wherein said first velocity is less than said second velocity.

Advantageously the apparatus wherein said first velocity is between 5 percent and 20 percent of said second velocity.

According to yet another aspect of the invention there is provided a method for forging, said method including providing a workpiece to be formed; providing a moveable first tooling member configured to form said workpiece upon impact with said workpiece and a moveable second tooling member configured to form said workpiece upon impact with said workpiece, said first tooling member and said second tooling member each being moveable relative to one another; balancing a momentum of said first tooling member with a momentum of said second tooling member such that a net momentum of a simultaneous impact with said workpiece by said first tooling member and said second tooling member is minimized; and forming said workpiece in response to an impact force generated by said simultaneous impact with said workpiece by said first tooling member and said second tooling member.

Advantageously the method wherein said first tooling member and said second tooling member both move in a linear path to effect said simultaneous impact.

Advantageously the method wherein said balancing step comprises controlling a velocity of said first tooling member and a velocity of said second tooling member at said simultaneous impact.

Advantageously the method wherein said velocity of said first tool member and said velocity of said second tooling member are controlled such that said momentum of said first tooling member is within 5 percent of said momentum of said second tooling member at said simultaneous impact.

Advantageously the method wherein said velocity of said first tool member and said velocity of said second tooling member are controlled such that said momentum of said first tooling member is substantially equal to said momentum of said second tooling member at said simultaneous impact.

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.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a front schematic view of one embodiment of the disclosed apparatus for forging;

Fig. 2 is a front schematic view of the disclosed apparatus for forging of Fig. 1 ;

Fig. 3 is a schematic view of the tooling members of the disclosed apparatus for forging shown at an initial position;

Fig. 4 is a schematic view of the tooling members of Fig. 3 shown at an impact position;

Fig. 5 is a schematic view of the tooling members of Fig. 3 shown at a final position;

Fig. 6 is a front schematic view of another embodiment of the disclosed apparatus for forging; Fig. 7 is a front schematic view of the disclosed apparatus for forging of Fig. 6;

Fig, 8 is a schematic view of another embodiment of the disclosed apparatus for forging;

Fig, 9 is a flow diagram depicting an embodiment of the disclosed method for forging;

Fig, 10 is a flow diagram of aircraft production and service methodology; and

Fig, 11 is a block diagram of an aircraft. DETAILED DESCRIPTION

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 Figs. 1 and 2, the disclosed apparatus for forging, generally designated 10, may include a machine frame 12, a first (e.g., lower) tooling member 14, and a second (e.g., upper) tooling member 16. Each of the first tooling member 14 and the second tooling member 16 may be moveable with respect to the frame 16. The disclosed apparatus for forging 10 may form a momentum-balanced system such that the net momentum following a forging impact is minimized (e.g., approximately zero).

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 (Fig. 3) may be applied to a workpiece 32 positioned between the first tooling member 14 and the second tooling member 16 (e.g., at an impact zone 30). The impact force Fi may be suitable to deform the workpiece 32 (e.g., create a desired geometric change to the material of the workpiece 32).

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 10 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 10. 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 10 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 (Fig. 3) may deform the workpiece 32.

Referring to Figs. 3-5, the forging process may include a single impact or a plurality of impacts upon the workpiece 32. Each impact may be the result of one cycle of operation of the first tooling member 14 and the second tooling member 16. Each cycle may include a single drive stroke and a single return stroke of each of the first tooling member 14 and the second tooling member 16.

The first tooling member 14 may begin at a first initial position Pli. The drive stroke of the first tooling member 14 may include movement from the first initial position Pli, through a first impact position Pl ₂ , and to a first final position Pl ₃ (Fig. 5). The second tooling member 16 may begin at a second initial position P2i. The drive stroke of the second tooling member 16 may include movement from the second initial position P2i, through a second impact position P2 ₂ , and to a second final position P2 ₃ (Fig. 5). The impact positions Pl ₂ , P2 ₂ 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 Pl ₃ , P2 ₃ (Fig. 5) may be the respective locations of the tooling members 14, 16 after work has been performed on the workpiece 32 (e.g., immediately after impact) and the workpiece 32 has been at least partially deformed. The return stroke of the first tooling member 14 may include movement from the first final position Pl ₃ (Fig. 5) to the first initial position Pli. The return stroke of the second tooling member 16 may include movement from the second final position P2 ₃ (Fig. 5) to the second initial position P2i.

The first tooling member 14 may translate between the first initial position Pli and the first final position Pl ₃ (e.g., along the longitudinal axis A (Fig. 1) of the machine frame 12). The second tooling member 16 may translate between the second initial position P2i and the second final position P2 ₃ (e.g., along the longitudinal axis A of the machine frame 12).

The distance between the impact position Pl ₂ and the final position Pl ₃ of the first tooling member 14 and the impact position P2 ₂ and the final position P2 ₃ 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 Figs. 3-5, the first tooling member 14 and any components that move with the first tooling member 14 may include a first mass Mi. The first driving mechanism 26 (Figs. 1 and 2) may apply a first force Fi to move the first tooling member 14 and any components that move with the first tooling member 14 (e.g., the first mass Mi). The first tooling member 14 may have a first initial velocity Vli (Fig. 3) at the first initial position Pli, a first impact velocity Vl ₂ (Fig. 4) at the first impact position Pl ₂ (e.g., immediately before impact), and a first final velocity Vl ₃ (Fig. 5) at the first final position PI ₃ (e.g., immediately after impact).

The second tooling member 16 and any components that move with the second tooling member 16 may include a second mass M ₂ . The second driving mechanism 28 may apply a second force F ₂ to move the second tooling member 16 and any components that move with the second tooling member 16 (e.g., the second mass M ₂ ). The second tooling member 16 may have a second initial velocity V2i (Fig. 3) at the second initial position P2i, a second impact velocity V2 ₂ (Fig. 4) at the second impact position P2 ₂ (e.g., immediately before impact), and a second final velocity V2 ₃ (Fig. 5) at the second final position P2 ₃ (e.g., immediately after impact).

The first tooling member 14 may begin at rest (e.g., where the initial velocity Vli is zero at the initial position Pli). The first tooling member 14 may move a first distance Di between the initial position Pli and the impact position Pl ₂ . The first force Fi may be suitable for the first tooling member 14 to achieve the impact velocity Vl ₂ at the impact position Pl ₂ . Upon impact, the first tooling member 14 may move a first distance di between the impact position Pl ₂ and the final position Pl ₃ deforming the workpiece 32.

The second tooling member 16 may begin at rest (e.g., where the initial velocity V2i is zero at the initial position P2i). The second tooling member 16 may move a second distance D ₂ between the initial position P2i and the impact position P2 ₂ . The second force F ₂ may be suitable for the second tooling member 16 to achieve the impact velocity V2 ₂ at the impact position P2 ₂ . Upon impact, the second tooling member 16 may move a second distance d ₂ between the impact position P2 ₂ and the final position P2 ₃ 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 Pl ₂ and the second tooling member 16 at the second impact position P2 ₂ ) is:

M ₁ V1 ₂ = M ₂ V2 ₂ (Eqn. 2) wherein, Mi is the mass of the first tooling member 14 and any components that move with the first tooling member 14, Vl ₂ 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 Pl ₂ , M ₂ is the mass of the second tooling member 16 and any components that move with the second tooling member 16, and V2 ₂ 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 P2 ₂ . 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 ( | MiVl ₂ | - | M ₂ V2 ₂ | = 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 (MiVl ₂ ) of the first tooling member 14 at the first impact position Pl ₂ to be within 20 percent of the momentum (M ₂ V2 ₂ ) of the second tooling member 16 at the second impact position P2 ₂ . In another expression, the net momentum may be minimized by configuring the momentum (Mi VI 2) of the first tooling member 14 at the first impact position Pl ₂ to be within 10 percent of the momentum (M ₂ V2 ₂ ) of the second tooling member 16 at the second impact position P2 ₂ . In yet another expression, the net momentum may be minimized by configuring the momentum (MiVl ₂ ) of the first tooling member 14 at the first impact position Pl ₂ to be within 5 percent of the momentum (M ₂ V2 ₂ ) of the second tooling member 16 at the second impact position P2 ₂ . 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 Mi relative to the mass M ₂ of the second tooling member 16) and may move at a relatively slow velocity (e.g., an impact velocity Vl ₂ significantly less than the impact velocity V2 ₂ of the second tooling member 16). The second tooling member 16 may include a relatively light member (e.g., having a small mass M ₂ relative to the mass Mi of the first tooling member 14) and may move at a very high velocity (e.g., an impact velocity VF ₂ significantly greater than the impact velocity Vl ₂ of the first tooling member 14). As described above, the apparatus for forging 10 may be configured such that the first mass Mi at impact velocity Vl ₂ is equal to the second mass M ₂ at impact velocity V2 ₂ such that the momentum P at the instant of impact is balanced.

For example, the second mass M ₂ of the second tooling member 16 may be between approximately 20 percent and 50 percent of the first mass Mi of the first tooling member 14 and the impact velocity VI ₂ of the first tooling member 14 may be between approximately 20 percent and 50 percent of the impact velocity V2 ₂ of the second tooling member 16.

As another example, the second mass M ₂ of the second tooling member 16 may be between approximately 10 percent and 20 percent of the first mass Mi of the first tooling member 14 and the impact velocity V2i of the first tooling member 14 may be between approximately 10 percent and 20 percent of the impact velocity V2 ₂ of the second tooling member 16.

As another example, the second mass M ₂ of the second tooling member 16 may be between approximately 5 percent and 10 percent of the first mass Mi of the first tooling member 14 and the impact velocity V2i of the first tooling member 14 may be between approximately 5 percent and 10 percent of the impact velocity V2 ₂ of the second tooling member 16. As another example, the second mass M ₂ of the second tooling member 16 may be less than 5 percent of the first mass Mi of the first tooling member 14 and the impact velocity V2i of the first tooling member 14 may be less than 5 percent of the impact velocity V2 ₂ 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 Mi of 22.68 kg) and an impact velocity Vl ₂ of 30 ft/s (9.14 m/s). The second tooling member 16 may have a weight of 5 lbs. (mass M ₂ of 2.268 kg) and an impact velocity V2 ₂ 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 Mi 226.8 kg) and an impact velocity Vl ₂ of 10 ft/s (3.05 m/s). The second tooling member 16 may have a weight of 50 lbs. (mass M ₂ 22.68 kg) and an impact velocity V2 ₂ of 100 ft/s (30.48 m/s).

Referring again to Figs. 1 and 2, in an example embodiment, the disclosed apparatus for forging 10 may take the form of an open die forging-type machine. The first tooling member 14 may include a first die 36 (e.g., an anvil). The first die 36 may include a first die surface 40 configured to deform the workpiece 32 upon impact. The die surface 40 may be substantially flat, substantially concave, substantially convex, or a combination thereof. The second tooling member 16 may include a second die 38 (e.g., a hammer). The second die 38 may include a second die surface 42 configured to deform the workpiece 32 upon impact. The second die surface 42 may be substantially flat, substantially concave, substantially convex, or a

combination thereof.

In an example implementation, as illustrated in Fig. 1, the workpiece 32 may be positioned upon the surface 40 of the first die 36 and moved toward the impact zone 30 with the first die 36. Thus, the first mass Mi of the first tooling member 14 may include the mass of the first die 36 and the mass of the workpiece 32. As illustrated in Fig. 2, upon impact of the second die 38 with the workpiece 32, the impact force ¥ _t may deform the workpiece 32 (e.g., reducing the height of the workpiece 32 and increasing the width of the workpiece 32) into a fully or partially forged part 34.

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 Mi 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 Figs. 6 and 7, in another example embodiment, the disclosed apparatus for forging 10 may take the form of a closed die (e.g., impression die) forging-type machine. The first tooling member 14 may include a first die 44 (e.g., a mold). The first die 44 may include a first die surface 46 that defines at least one first cavity 48. The first tooling member 14 may include a first bolster plate 50 configured to securely hold the first die 44. The first die 44 may be rigidly connected (e.g., removably) or affixed (e.g., integrally) to the first bolster plate 50. For example, the first die 44 may be connected to the first bolster plate 50 by one or more mechanical fasteners (not shown). The fasteners may include any suitable mechanism configured to securely connect the first die 44 to the first bolster plate 50 including, but not limited to, bolts, clamps, brackets, pins, rails, or any other fastening means.

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 Fig. 6, the workpiece 32 may be positioned with the cavity 48 of the first die 44 and moved toward the impact zone 30 with the first die 44. Thus, the first mass Mi (Fig. 3) of the first tooling member 14 may include the mass of the first die 44, the mass of the first bolster plate 50, the mass of the workpiece 32, and optionally the mass of the secondary mass 60. As illustrated in Fig. 7, upon impact of the second die 52 with the workpiece 32 (Fig. 6), the impact force ΐι (Fig. 5) may deform the workpiece 32 (Fig. 6), such as by expanding the workpiece 32 within the combination of the first cavity 48 and the second cavity 56 (Fig. 6), thereby forming a fully or partially forged part 34.

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 Mi 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 ΐι 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 Fi and F ₂ required to move the first tooling member 14 and the second tooling member 16 at respective impact velocities Vl ₂ , V2 ₂ 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 Fi and the second force F ₂ 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 Pl _1? P2 _1? 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 Fig. 8, the apparatus for forging 10 may include at least one energy source 68 connected to the first driving mechanism 26 and the second driving mechanism 28. The energy source 68 may provide power to the driving mechanisms 26, 28 to generate the first force ¥i and the second force F ₂ , respectively (Fig. 4). For example, the energy source 68 may supply electricity to a pump for a pneumatic or hydraulic drive mechanism or a motor for a mechanical drive mechanism. As another example, the energy source 68 may supply fuel to a combustion drive mechanism.

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 Vl ₂ , V2 ₂ of the tooling members 14, 16, respectively. For example, the controller 70 may adjust the driving forces Fi, F ₂ applied to the tooling members 14, 16 by the driving mechanisms 26, 28.

The impact velocities Vl ₂ , V2 ₂ of one or both of the tooling members 14, 16 and thus, the driving forces Fi, F ₂ 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 Mi, M ₂ of one or both of the tooling members 14, 16 changes, the driving forces F _1? F ₂ required may need to be adjusted in order to achieve the impact velocities Vl ₂ , V2 ₂ 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 P2i, P2 ₂ ). 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 Fi, F ₂ .

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 di of the first tooling member 14 between the impact position Pl ₂ and the final position Pl ₃ and the second distance d ₂ of the second tooling member 16 between the impact position P2 ₂ and the final position P2 ₃ .

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 = v ² /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:

F _! = MV ² /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 P ₂ and final position P ₃ ).

The driving force F may be determined by the following equation:

F = MV ² /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 Pi and impact position P ₂ ).

Thus, given certain operational parameters (e.g., impact force F _I? distance di, d ₂ , distance Di, D ₂ , and/or mass Mi, M ₂ 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 V ₂ of either tooling member 14, 16 and any components that move with the tooling member, or the driving force Fi, F ₂ ) (Figs. 3-5).

Eqn. 2 may be used to determine the required mass Mi, M ₂ of an opposed tooling member 14, 16 and any components that move with the tooling member and/or the required impact velocity V ₂ 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 Fig. 9, also disclosed is a method, generally designated 100, for momentum- balanced forging. As shown at block 102, the method 100 may begin by determining various operational conditions for a forging process. Examples of operational conditions for the forging process may include the impact force ¥ _t required to deform the workpiece 32, the desired deformation or displacement d of the workpiece 32, available driving forces Fi, F ₂ , and the like. Other examples of operational conditions may include the size and geometry of the workpiece 32 to be forged, the accuracy desired, the strength of the workpiece material, the temperature that the workpiece 32 is formed, the desired mechanical properties of the final forged part 34, the sensitivity of the workpiece 32 to strain rate, the amount of forged parts 34 to be produced, the time to produce the forged part 34, and the like. 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 V2i, V2 ₂ 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 V2i, V2 ₂ of the first tooling member 14 and/or the second tooling member 16, respectively, may be adjusted by modifying the first driving force ¥i applied to the first tooling member 14 by the first driving mechanism 26 and/or the second driving force F ₂ 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 Fig. 10, and an aircraft 202, as shown in Fig. 11. During pre-production, example method 200 may include specification and design 204 of the aircraft 202 and material procurement 206. During production, component and subassembly

manufacturing 208 and system integration 210 of the aircraft 202 takes place. Thereafter, the aircraft 202 may go through certification and delivery 212 in order to be placed in service 214. While in service by a customer, the aircraft 202 is scheduled for routine maintenance and service 216, which may also include modification, reconfiguration, refurbishment and the like.

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 Fig. 11, the aircraft 202 produced by example method 200 may include an airframe 218 with a plurality of systems 220 and an interior 222. Examples of high-level systems 220 include one or more of a propulsion system 224, an electrical system 226, a hydraulic system 228, and an environmental system 230. Any number of other systems may be included. Although an aerospace example is shown, the principles of the invention may be applied to other industries, such as the automotive industry.

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.