A production method for medium and large caliber projectile bodies

Abstract

The invention relates to a production method for medium and large caliber projectile bodies. The invention particularly relates to a method for producing medium and large caliber projectile bodies in a shorter time and with fewer operations.

Description

[0001] A PRODUCTION METHOD FOR MEDIUM AND LARGE CALIBER PROJECTILE BODIES

[0002] Technical Field

[0003] The invention relates to a production method for medium and large caliber projectile bodies.

[0004] The invention particularly relates to a method for producing medium and large caliber projectile bodies in a shorter time and with fewer operations.

[0005] State of the Art

[0006] Ammunition comprises three main components: the casing, the projectile body and the fuze. As a result of the pressure and thrust created by the explosion of the gunpowder inside the casing, the projectile body separates from the casing and heads towards the target. The type of destruction it will create on the target (instant explosion, delayed explosion, etc.) is determined by the fuze.

[0007] The terms medium and large caliber refer to various size categories of ammunition used with firearms. Caliber refers to the diameter of a projectile body or weapon and is usually measured in millimeters. The terms medium and large caliber are used to refer to the general dimensions of ammunition, although the precise meanings of these terms may vary depending on the type of weapon used, military or civilian use, and geographic region.

[0008] Medium caliber ammunition can generally have diameters ranging from 20 to 60 mm. These ammunitions are mostly used in weapons such as anti-aircraft and naval guns. Large caliber projectiles generally have diameters greater than 60 mm. Ammunition in this category is generally used in tanks and howitzers.

[0009] In the state of the art, two methods are used for producing projectile bodies and they can be summarized as follows, based on the basic operations that give the body its basic shape: • Hot pressing (comprising hot centering, punching and drawing stages) and hot muzzle necking and subsequent production operations from bar (solid with cylindrical or square profile and usually steel) material.

[0010] • Hot and cold pressing (comprising hot centering, punching and subsequent cold drawing stages) and hot muzzle necking and subsequent production operations from bar (cylindrical or square profile solid and usually steel) material.

[0011] In the state of the art, the sequence of operations for the production of projectile bodies is usually as follows: Bar cutting, pressing, rough sandblasting, length cutting, bottom milling, center determination, rough draft turning, full (finish) draft turning, muzzle necking and subsequent operations. The structural problems observed in the above-mentioned operations can be summarized as follows:

[0012] • The “pressing” operation (following induction furnace since it involves hot forming) comprises centering and punching and drawing stages, and since the relevant stages are labor intensive, the number of operators required to work in the operation (5~10 persons depending on the ammunition) is high. Alternatively, although the commissioning of robotic systems is possible, the required investment costs are very high.

[0013] • Since the “pressing” operation involves hot forming, both the materials (hot work tool steels) and the production (large diameters, long lengths, precise surface finishes and heat treatment) of the tools that need to be used are costly.

[0014] • The tooling required for the “pressing” operation takes a long time to manufacture (at least 3 weeks), which creates a handicap in terms of rapid prototyping and qualification, especially when it comes to new munitions.

[0015] • Since the “pressing” operation involves hot forming, the working life of the tools used is short. For example, the pressing tool used in the “punching” stage, referred to as the punch, must be renewed after every -150 operations because it becomes unusable.

[0016] • Since the “pressing” operation involves hot forming, a layer of iron-oxide called “scale” is formed on the surface of the workpiece at the end of the operation, and the relevant layer must be cleaned with a “coarse sandblasting” operation (in order to ensure measurement accuracy in subsequent operations). The operation is labor intensive and the number of operators (at least 2 persons) required to work in the operation is high. • Scales originating from the “pressing” operation and which cannot be completely cleaned with the “rough sandblasting” operation must be cleaned with the “bottom milling” operation. By holding an illuminator inside the projectile body, the operator first detects the relevant scales through visual inspection and then cleans them with the help of a suitable cutting tool. The mentioned operation is labor intensive and the operation time is long.

[0017] • The infrastructure and machine tool investments required for the “pressing” operation are very costly, and therefore the number of suppliers in the domestic market where the relevant operation can be subcontracted at the subcontractor level is limited, and does not exist for large caliber ammunition. This situation prolongs deadlines and increases strategic risks for a limited number of companies, which are the main contractors in the supply of projectile bodies for TO rkiye, in the event of orders exceeding their capacities.

[0018] • Machining allowances (due to the minimizable but non-zero misalignment caused by the pressing operation) are high (7~15 mm depending on the ammunition) in “rough and full draft turning” operations. This situation increases the depth of cut in a single pass in order to keep the operation times at a reasonable level and therefore structurally prevents the execution of the relevant operations on conventional CNC machines (since the slide strengths will be insufficient). Hydraulically fed copy lathes are used for the operations mentioned above, but the fact that these are old (about 50 years old) machines that are not currently mass-produced brings with it the handicaps of both periodic adjustment and setup disruption and malfunctioning. Alternatively, it is possible to commission double-turret CNC lathes, but in this case the required investment costs are high.

[0019] • In “rough and full draft turning” operations, in order to clamp the workpiece to the lathe, both an additional operation called “center determination” (because the workpiece is long, heavy and has a closed back) and clamping tools called “spindle arbor” (because the inner surface of the workpiece will not be smooth after the pressing operation) are needed to fix the workpiece to the lathe by tightening the workpiece from the inside by means of sockets. The production and assembly of the relevant clamping tools take a long time, thus increasing the tooling and qualification time and costs.

[0020] As a result of the research made on the subject, GB469550A has been encountered. The subject application relates to a method and apparatus for producing ammunition projectiles and similar casings, comprising the steps of first forming a casing having a non-perforated end by a forging process and then finishing it by an extrusion process.

[0021] As a result, due to the abovementioned disadvantages and the insufficiency of the current solutions regarding the subject matter, a development is required to be made in the relevant technical field.

[0022] Object of the Invention

[0023] The present invention aims to solve the above-mentioned drawbacks, and it is inspired by the current situation

[0024] The main object of the present invention is to eliminate the structural problems in the operations from bar cutting to the muzzle necking stage in the production of medium and large caliber projectile bodies.

[0025] Another object of the present invention is to eliminate the need for "pressing", "rough sandblasting", "length cutting", "bottom milling", "center determination", "rough draft turning" and "full draft turning" operations by starting production with hollow bar (2.1 ) instead of bar (1.1 ).

[0026] Another object of the present invention is to reduce the number of operators, labor, time and investment costs in the production of medium and large caliber projectile bodies.

[0027] In order to fulfill the above-described purposes, the invention is a production method for medium and large caliber projectile bodies having an alternative projectile body comprising a rear cover to be mounted on a main body to be manufactured from a hollow bar material, comprising:

[0028] • Hollow bar cutting, which comprises cutting the hollow bar material to suit the caliber of the projectile to be produced,

[0029] • draft turning, which comprises the production of the inner and outer profile of the hollow bar material to suit the projectile caliber,

[0030] • muzzle necking, which comprises shaping the end of the right side of the hollow bar material by compressing or closing the same and subsequent operations comprising subsequent production for the purpose of obtaining the main body and rear cover and assembly processes for the purpose of obtaining the alternative projectile body.

[0031] The structural and characteristic features of the present invention will be understood clearly by the following drawings and the detailed description made with reference to these drawings and therefore the evaluation shall be made by taking these figures and the detailed description into consideration.

[0032] Figures Clarifying the Invention

[0033] Figure 1 shows the production method steps used in the prior art.

[0034] Figure 2 shows the steps of the production method of the present invention.

[0035] Description of the Part References

[0036] 1.1 Bar

[0037] 1 .2 Conventional projectile body

[0038] 1 .2a Conventional projectile body rear inner profile

[0039] 2.1 Hollow bar

[0040] 2.2 Main body

[0041] 2.3 Rear cover

[0042] 2.4 Alternative projectile body

[0043] 2.4a Alternative projectile body rear inner profile

[0044] 101 Bar cutting

[0045] 102 Pressing

[0046] 103 Rough sandblasting

[0047] 104 Length cutting

[0048] 105 Bottom milling

[0049] 106 Center determination

[0050] 107 Rough draft turning

[0051] 108 Full draft turning

[0052] 109 Muzzle necking

[0053] 110 Subsequent operations

[0054] 201 Hollow bar cutting 202 Draft turning

[0055] 203 Muzzle necking

[0056] 204 Subsequent operations

[0057] Detailed Description of the Invention

[0058] In this detailed description, the preferred embodiments of the production method of the present invention are described by means of examples only for clarifying the subject matter.

[0059] The medium and large caliber projectile bodies to be produced with the production method which is the subject of the invention comprises a main body (2.2) obtained by processing a hollow bar (2.1 ) and an alternative projectile body (2.4) comprising a rear cover (2.3).

[0060] In the production method, which is the subject of the invention, production will start with hollow bar cutting (201 ) the appropriately sized hollow bar (2.1 ) to the desired length.

[0061] After the hollow bar cutting (201 ) operation is completed, the draft turning (202) operation is applied to the workpiece. The turning process will preferably be carried out on a CNC lathe, and it is aimed to obtain the external and internal profiles required for the muzzle necking (203) operation. For this process, the workpiece is connected to the chuck at the left inner diameter and is taken to steady rest in the center. In this way, by entering the workpiece from the right side with the tool from the inside, the internal profile to be obtained in this area is machined to the desired extent. Subsequently, the workpiece remains fixed to the chuck at the left inner diameter, but the steady rest is deactivated, and the outer profile of the part can be machined to the desired extent with diameter tailstock from the right side on the part. This operation is called draft turning (202).

[0062] As a result of the completion of the draft turning (202) operation, the workpiece becomes ready for the muzzle necking (203) operation. The muzzle necking (203) operation is the shaping process of the workpiece by squeezing or closing the end of the right side. This operation is usually done to direct the tip of the projectile body to the target more effectively or to increase projectile performance. The muzzle necking (203) operation improves the aerodynamic properties of the projectile body, provides a smoother flight during shooting and ensures that it hits the target more precisely. After the muzzle necking (203) operation, the main body (2.2) will be manufactured as a result of the completion of the subsequent production operations (which will not differ from the subsequent operations of the conventional projectile body to the extent that it is worth making an application), and the production process will be completed with the assembly of the rear cover (2.3) (which will be manufactured by operations to be carried out in parallel) by screwing and / or welding and / or similar method, and the alternative projectile body (2.4), whose external profile will be exactly the same as the conventional projectile body (1 .2) produced by conventional methods, will be obtained.

[0063] The rear inner profile (2.4a) obtained by the inventive production method differs from the conventional projectile body rear inner profile (1 .2a) in that the rear inner profile (2.4a) is shaped by the production method rather than being functional (related to the ballistics or strength of the projectile body or the amount of spacing) (in the state of the art, the punch tip profile is radiused to prevent the same from sinking into the material during the pressing (102) operation, and tapered for easy ejection, resulting in the conventional projectile body rear inner profile (1.2a)). Therefore, as long as the ballistic (weight and center of gravity and outer profile), strength and spelling requirements are met (as in the alternative production method subject to the invention), there will be no drawback in revising the rear inner profile due to the change in production method.

[0064] As a result, with the inventive production method, medium and large caliber projectile bodies will be obtained with hollow bar cutting (201 ), draft turning (202), muzzle necking (203) and subsequent operation (204) (manufacturing and assembly operations), and the need for bar cutting (101 ), pressing (102), rough sandblasting (103), length cutting (104), bottom milling (105), center determination (106), rough draft turning (107) and full draft turning (108) operations applied in the state of the art will be eliminated. The process steps of the production method used in the state of the art are shown in Figure 1.

Claims

CLAIMS1. A production method for medium and large caliber projectile bodies having an alternative projectile body (2.4) comprising a rear cover (2.3) to be mounted on a main body (2.2) to be manufactured from a hollow bar (2.1), characterized by comprising:• hollow bar cutting (201 ), which comprises cutting the hollow bar (2.1) to suit the caliber of the projectile to be produced,• draft turning (202), which comprises the production of the inner and outer profile of the hollow bar (2.1 ) to suit the projectile caliber, • muzzle necking (203), which comprises shaping the end of the right side of the hollow bar (2.1) by compressing or closing the same and• subsequent operations (204) comprising subsequent manufacture for the purpose of obtaining the main body (2.2) and rear cover (2.3) and assembly processes for the purpose of obtaining the alternative projectile body (2.4).

2. The production method according to claim 1 , characterized in that the draft turning(202) process is performed on a CNC lathe.

3. The production method according to claim 1 or 2, characterized in that; the rear cover (2.3) is screwed and / or welded to the hollow bar (2.1).

Images