A method for finish machining a three-piece shell holder

Abstract

The present application relates to a kind of fastening methods for finishing three-petal propellant holder.By the interference fit of the first fastening ring with the first clamping part of three-petal propellant holder, the interference fit of the second fastening ring with the second clamping part of three-petal propellant holder, and the use of machine tool fixture, the spot welding three-petal process in traditional machining method can be eliminated. The problem of current machining method with many processes and affecting tool life is solved. There is no welding spot on the three-petal propellant holder of the present application, which can prolong the service life of the tool; the fastening ring can be reused, and the fastening method is reliable, easy to operate, which can effectively ensure the machining precision of three-petal propellant holder.

Description

Technical Field

[0001] This invention belongs to the field of machining technology for large armor projectiles, and in particular relates to a fastening method for precision machining of three-lobed projectile sabots. Background Technology

[0002] Large-caliber armor-piercing projectiles, as kinetic energy destroyers, are widely used in my country's national defense. The sabot is a crucial component of these projectiles. During firing, the sabot centers and stabilizes the projectile within the gun barrel, and also transfers the kinetic energy of the propellant. As the projectile leaves the barrel, the three-lobed sabot detaches at high speed due to air resistance and centrifugal force.

[0003] In traditional cartridge case machining, the raw material is an aluminum billet. After rough machining, the cartridge case is sawn into three 120° sections along the axial direction, followed by milling of the 120° surfaces. To further refine the three-section cartridge case, the traditional process requires spot welding the three saw kerfs at the joint to form weld points (e.g., 080°). Figure 1 ), so that it returns to its rotating state.

[0004] Given the increasing emphasis on safety and quality, spot welding the three segments of the sabot is no longer suitable for current development trends, mainly due to the following disadvantages:

[0005] 1. The spot welding method used is argon arc welding, and the equipment used has certain safety hazards and requires industrial land.

[0006] 2. During welding, the gas fumes produced are harmful to the human body. If protection is not in place, the welding light can cause burns to the eyes.

[0007] 3. After finishing, the weld points are removed, so an additional process is required;

[0008] 4. The raised part of the solder joint has a certain impact on the tool life. Summary of the Invention

[0009] This invention provides a fastening method for precision machining of a three-lobed spring support, which solves the problem of multiple machining steps and reduced tool life in current machining methods.

[0010] This invention is achieved through the following technical solutions:

[0011] A fastening method for precision-machined three-lobed sabots includes a first fastening ring 010, a second fastening ring 020, a three-jaw chuck jaw 040, a top cup 050, a first clamp 060, and a second clamp 070. The first and second fastening rings have the same structure, both being two-lobed. One end of each half-ring is hinged with a cylindrical pin, and the other end has an operating hole. A bolt passing through the operating hole can fasten the two half-rings together. The specific steps are as follows:

[0012] 1) Provide a three-lobed spring support after rough machining, sawing, and milling a 120° surface;

[0013] 2) The two retaining rings of the first fastening ring 010 are hinged by the first cylindrical pin 011, and the two retaining rings of the second fastening ring 020 are hinged by the cylindrical pin 021. After the first fastening ring 010 is fastened by the first fastening bolt 012, the inner diameter of the first fastening ring 010 is interference-fitted with the outer diameter of the first clamping part of the sabot 030; after the second fastening ring 020 is fastened by the second fastening bolt 022, the inner diameter of the second fastening ring 020 is interference-fitted with the outer diameter of the second clamping part of the sabot 030.

[0014] 3) During the precision machining of the centering part, the three-lobed spring support 030 is clamped and positioned by the first fastening ring 010, the second fastening ring 020, the three-jaw chuck jaws 040 and the top cup 050.

[0015] 4) When performing the process of windward groove 081 and front half annular groove 082, the three-lobed spring support 030 is clamped and positioned by the first fastening ring 010, the second fastening ring 020 and the first clamp 060. At this time, the end face of the windward groove 081 of the three-lobed spring support 030 protrudes from the clamping end face of the first clamp 060 at this time.

[0016] 5) When performing the finishing machining of the bottom groove 084 and the rear half of the annular groove 083, the three-lobed spring support 030 is clamped and positioned by the first fastening ring 010, the second fastening ring 020 and the second clamp 070. At this time, the end face of the bottom groove 084 of the three-lobed spring support 030 protrudes from the clamping end face of the second clamp 070 at this time. At the same time, the first fastening ring 010 needs to be removed when finishing machining the bottom groove 084.

[0017] The present invention has no weld points on the three-lobed spring support, which can extend the service life of the tool; the fastening ring is reusable and the fastening method is reliable and easy to operate, which can effectively ensure the machining accuracy of the three lobes of the spring support. Attached Figure Description

[0018] Figure 1 Axonometric drawing of the spring support before the solder joints are removed;

[0019] Figure 2 This is a clamping diagram of the precision machining centering part of the present invention;

[0020] Figure 3 This is a cross-sectional view of the windward groove and the front half of the annular groove of the present invention.

[0021] Figure 4 and Figure 5 This is a cross-sectional view of the precision-machined bottom groove and the clamping diagram of the rear half of the annular groove of the present invention.

[0022] Figure 6 This is an isometric view of the first fastening ring of the present invention;

[0023] Figure 7 This is an isometric view of the second fastening ring of the present invention;

[0024] Figure 8 This is a cross-sectional view of the top cup of the present invention; Detailed Implementation

[0025] This invention provides a fastening method for precision-machined three-lobed cartridge sabots, the fastening method comprising:

[0026] Provides a three-lobed spring support that has undergone rough machining, sawing into three lobes, and milling a 120° surface;

[0027] Both the first and second fastening rings are made of metal, such as 40Gr.

[0028] The two retaining rings of the first fastening ring 010 are hinged together by the first cylindrical pin 011, and the two retaining rings of the second fastening ring 020 are hinged together by the cylindrical pin 021.

[0029] Furthermore, after the first fastening ring 010 is fastened by the first fastening bolt 012, the inner diameter of the first fastening ring 010 is interference-fitted with the outer diameter of the first clamping part of the cartridge 030; after the second fastening ring 020 is fastened by the second fastening bolt 022, the inner diameter of the second fastening ring 020 is interference-fitted with the outer diameter of the second clamping part of the cartridge 030.

[0030] Furthermore, during the precision machining of the centering part, the three-lobed spring support 030 is clamped and positioned by the first fastening ring 010, the second fastening ring 020, the three-jaw chuck jaws 040, and the top cup 050.

[0031] Furthermore, during the process of the windward groove 081 and the first half of the annular groove 082, the three-lobed spring support 030 is clamped and positioned by the first fastening ring 010, the second fastening ring 020 and the first clamp 060.

[0032] Furthermore, during the finishing machining of the bottom groove 084 and the rear half of the annular groove 083, the three-lobed spring support 030 is clamped and positioned by the first fastening ring 010, the second fastening ring 020 and the second clamp 070; in particular, the first fastening ring 010 needs to be removed when finishing machining the bottom groove 084.

[0033] Example:

[0034] like Figure 2 As shown, during the precision machining of the centering part, the three-lobed spring support 030 is clamped and positioned by the first fastening ring 010, the second fastening ring 020, the three-jaw chuck jaws 040, and the top cup 050.

[0035] like Figure 3As shown, during the process of the windward groove 081 and the first half of the annular groove 082, the three-lobed spring support 030 is clamped and positioned by the first fastening ring 010, the second fastening ring 020 and the first clamp 060.

[0036] like Figure 4-5 As shown, during the finishing machining of the bottom groove 084 and the rear half of the annular groove 083, the three-lobed spring support 030 is clamped and positioned by the first fastening ring 010, the second fastening ring 020 and the second clamp 070; during the finishing machining of the bottom groove 084, in order to prevent the first fastening ring 010 from interfering with the cutting tool, the first fastening ring 010 can be removed.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. All equivalent structural changes made based on the description and drawings of the present invention should be included within the scope of patent protection of the invention.

[0038] Compared with the prior art, the advantages and effects of the present invention are as follows:

[0039] 1. Eliminate the three-part spot welding process, thereby eliminating the safety hazards caused by argon arc welding and saving industrial land;

[0040] 2. During precision machining, there are no weld points on the three-lobed spring support, which can extend the tool life; 3. The fastening ring is reusable, and the fastening method is reliable and easy to operate; 4. It saves processing costs.

Claims

1. A fastening method for a precision-machined three-lobed spring clip, characterized in that: The system includes a first fastening ring, a second fastening ring, a three-jaw chuck, a top cup, a first clamp, and a second clamp. The first and second fastening rings have the same structure, both being two-part rings. One end of each half-ring is hinged with a cylindrical pin, and the other end has an operating hole. Bolts passing through the operating hole can fasten the two half-rings together. The specific steps are as follows: 1) Provide a three-lobed spring support after rough machining, sawing into three lobes, and milling a 120° surface; 2) The two halves of the first fastening ring are hinged together by the first cylindrical pin, and the two halves of the second fastening ring are hinged together by the cylindrical pin. After the first fastening ring is fastened by the first fastening bolt, the inner diameter of the first fastening ring is interference-fitted with the outer diameter of the first clamping part of the sabot. After the second fastening ring is fastened by the second fastening bolt, the inner diameter of the second fastening ring is interference-fitted with the outer diameter of the second clamping part of the sabot. 3) During the precision machining of the centering part, the three-lobed spring support is clamped and positioned by the first fastening ring, the second fastening ring, the three-jaw chuck jaws and the top cup; 4) When performing the process of the windward groove and the first half of the annular groove, the three-lobed spring support is clamped and positioned by the first fastening ring, the second fastening ring and the first clamp. At this time, the end face of the windward groove of the three-lobed spring support protrudes from the clamping end face of the first clamp at this point. 5) When performing the finishing machining of the bottom groove and the second half of the annular groove, the three-lobed spring support is clamped and positioned by the first fastening ring, the second fastening ring and the second clamp. At this time, the end face of the bottom groove of the three-lobed spring support protrudes from the clamping end face of the second clamp. At the same time, the first fastening ring needs to be removed when finishing machining the bottom groove.

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