Device and process for bonding free filling type grain in engine shell

Abstract

The invention discloses a device and process for bonding a free filling type grain in an engine shell. The device comprises a base, a mounting hole is formed in the base, and a mold cylinder, a front sealing head and a cavity formed by the front sealing head and the mold cylinder are arranged in the mounting hole; an annular bulge is arranged on the inner wall of the front sealing head; the adhesive and the annular protrusion are arranged between the front sealing head and the grain, the annular protrusion ensures that a certain gap is reserved between the grain and the front sealing head and is used for controlling the using amount of the filling glue or the adhesive, when the annular protrusion is prefabricated on the front sealing head, the height of the annular protrusion can be adjusted according to different product requirements, and by changing the height of the annular protrusion, the product quality is improved. The use amount of the adhesive can be controlled, in addition, the annular protrusions can better guarantee that the stress of the bottom of the grain is uniform, the posture of the grain in the vertical direction is accurate, then the bonding reliability and quality consistency are guaranteed, and the technical problems that in the prior art, a free filling type grain cannot achieve reliable bonding and the posture is accurate are solved.

Description

Technical Field

[0001] The invention belongs to the field of solid rocket engines, and relates to a bonding and fixing process in a free-loading type grain assembly process, and specifically to a device and a process for bonding free-loading type grains in an engine casing. Background Art

[0002] For small and medium-sized tactical missiles, in order to achieve a short-term high thrust of the missile to achieve the effect of rapid penetration, due to the limitation of the missile caliber, the solid propellant grains designed often use solid free-loading grains. In order to reliably fix the grains in the combustion chamber, a simple and feasible method is to use adhesives to bond the head of the grains to the front head of the engine to achieve a fixing effect. When bonding the grains, the selected adhesive needs to be left to cure for a certain period of time to achieve a reliable bonding effect. In addition, in order to ensure smooth airflow in the engine combustion chamber, the grains need to maintain a vertical fixed posture in the engine combustion chamber.

[0003] Therefore, what process to use to achieve reliable bonding of the grain and ensure that the grain is fixed in the combustion chamber as designed is an issue that needs to be considered during the engine assembly process. Summary of the invention

[0004] In view of the deficiencies in the prior art, the object of the present invention is to provide a device and process for bonding freely loaded charge in an engine casing, so as to solve the technical problem in the prior art that freely loaded charge cannot be bonded reliably and with accurate posture.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0006] A device for bonding freely loaded charge in an engine casing, comprising a base, a mounting hole being provided on the base, a mold barrel and a front head being provided in the mounting hole, a cavity being formed between the front head and the mold barrel; an annular protrusion being provided on the inner wall of the front head; an adhesive being provided on the upper surface of the front head, an amount of the adhesive being equal to the difference between the volume of a cavity formed by the inner surface of the front head, the inner wall of the mold barrel and the outer surface of the charge and the volume of the annular protrusion; and a thickness of the adhesive being the same as the height of the annular protrusion.

[0007] The present invention also includes the following technical features:

[0008] A limiting step is arranged on the inner wall of the bottom of the mold barrel, and the inner wall of the limiting step is fixedly connected to the outer wall of the front head.

[0009] The inner wall of the limiting step is threadedly connected to the outer wall of the front head.

[0010] A limiting convex ring is arranged on the outer wall of the mold cylinder.

[0011] The mounting hole of the base is threadedly connected to the mold cylinder.

[0012] The adhesive is a two-component epoxy resin adhesive.

[0013] A process for bonding free-loading grains in an engine casing, based on the device for bonding free-loading grains in an engine casing, comprises the following steps:

[0014] Step 1: determine the type of the drug column, determine the inner diameter and length of the mold barrel according to the outer diameter and length of the drug column, and determine the inner profile of the front head according to the head profile of the drug column;

[0015] Step 2: Connect the mold barrel and the front head base to the mold barrel according to the inner diameter of the mounting hole determined by the outer diameter of the mold barrel, and assemble the mold barrel and the front head;

[0016] Step 3: Pour a certain amount of mixed adhesive into the front end cap, and then vertically place the medicine column from above the mold barrel into the cavity formed by the front end cap and the mold barrel until the head of the medicine column contacts the annular protrusion on the front end cap;

[0017] Step 4: Let it stand for a while, and remove the base and the mold barrel after the adhesive solidifies, so that the drug column and the front head are reliably bonded and in the same posture.

[0018] The grain column is a composite propellant, and its aspect ratio is greater than, and the axial lower end of the grain column is in a butterfly shape.

[0019] The medicine column is provided with a coating layer except its axial upper end surface.

[0020] The coating layer is EPDM rubber.

[0021] Compared with the prior art, the present invention has the following beneficial technical effects:

[0022] (I) In the present invention, an adhesive and an annular protrusion are provided between the front head and the medicine column. The annular protrusion ensures that a certain gap is left between the medicine column and the front head, which is used to control the amount of filler or adhesive. When the annular protrusion is prefabricated on the front head, its height can be adjusted according to different product requirements. By changing the height of the annular protrusion, the amount of adhesive used can be controlled. In addition, the annular protrusion can better ensure that the force on the bottom of the medicine column is uniform, so that the posture of the medicine column in the vertical direction is accurate, thereby ensuring the reliability of bonding and quality consistency, and solving the technical problem in the prior art that the free-loading medicine column cannot achieve reliable bonding and accurate posture.

[0023] (II) The device of the present invention is suitable for bonding all small-sized free-loading grains with large aspect ratios. The size of the base and the mold barrel can be designed according to the type of propellant grain. The bonding posture of the grain can be controlled by designing the gap between the mold barrel and the grain, thereby improving the versatility of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 It is a partial enlarged view of the present invention;

[0026] Figure 3 It is a structural schematic diagram of the front head of the present invention;

[0027] Figure 4 It is a structural schematic diagram of the mold barrel of the present invention.

[0028] The meanings of the various numbers in the figure are: base 1, mold cylinder 2, front head 3, medicine column 5, adhesive 4, mounting hole 6, limiting step 7, limiting convex ring 8, annular protrusion 9, coating layer 10.

[0029] The specific contents of the present invention are further explained in detail below in conjunction with embodiments. DETAILED DESCRIPTION

[0030] It should be noted that, unless otherwise specified, all components in the present invention are components known in the art.

[0031] Specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0032] The present invention provides a device for bonding free-loading charge in an engine casing, comprising a base 1, a mounting hole 6 is provided on the base 1, a mold barrel 2 and a front head 3 are provided in the mounting hole 6, a cavity is formed between the front head 3 and the mold barrel 2; an annular protrusion 9 is provided on the inner wall of the front head 3; an adhesive 4 is provided on the upper surface of the front head 3, and the amount of the adhesive 4 is equal to the difference between the volume of a cavity formed by the inner surface of the front head 3, the inner wall of the mold barrel 2 and the outer surface of the charge 5 and the volume of the annular protrusion 9; the thickness of the adhesive 4 is the same as the height of the annular protrusion 9.

[0033] In the above technical scheme, an adhesive 4 and an annular protrusion 9 are arranged between the front head 3 and the medicine column 5. The annular protrusion 9 ensures that a certain gap is left between the medicine column 5 and the front head 3, which is used to control the amount of filler or adhesive. The height of the annular protrusion 9 can be adjusted according to different process requirements. By adjusting the height of the annular protrusion 9, the amount of adhesive 4 used can be controlled. In addition, the annular protrusion 9 can better ensure that the force at the bottom of the medicine column 5 is uniform, so that the vertical posture of the medicine column 5 is accurate, thereby ensuring the reliability and quality consistency of the bonding, and solving the technical problem that the free-loading medicine column in the prior art cannot achieve reliable bonding and accurate posture.

[0034] Preferably, the base 1 is made of 45# steel, with appropriate diameter and thickness to make the center of gravity of the whole device lower, so as to ensure that the device does not flip or deflect during the bonding process; the front head 3 is made of 30CrMnSiA alloy steel,

[0035] A limiting step 7 is provided on the inner wall of the bottom of the mold barrel 2 , and the inner wall of the limiting step 7 is fixedly connected to the outer wall of the front head 3 .

[0036] In the above technical solution, the limiting step 7 is used for axial limiting to ensure that the base 1 and the mold cylinder 2 are assembled in place.

[0037] The inner wall of the limiting step 7 and the outer wall of the front head 3 are connected by threads.

[0038] A limiting convex ring 8 is arranged on the outer wall of the mold cylinder 2 .

[0039] In the above technical solution, the limiting convex ring 8 is used to limit the axial displacement between the mold cylinder 2 and the base 1 .

[0040] The mounting hole 6 of the base 1 and the mold cylinder 2 are threadedly connected.

[0041] The adhesive 4 is a two-component epoxy resin adhesive.

[0042] In the above technical solution, the two components of adhesive 4 are mixed in a ratio of 1:1, and after the bonding is completed using adhesive 4, it needs to be left to stand for 4 hours for curing.

[0043] The present invention also provides a process for bonding free-loading powder columns in an engine casing, based on a device for bonding free-loading powder columns in an engine casing, comprising the following steps:

[0044] Step 1, determine the type of the medicine column 5, determine the inner diameter and length of the mold barrel 2 according to the outer diameter and length of the medicine column 5, and determine the inner profile of the front head 3 according to the head profile of the medicine column 5;

[0045] Step 2: according to the inner diameter of the mounting hole 6 determined by the outer diameter of the mold barrel 2, the mold barrel 2 and the base 1 of the front head 3 are connected to the mold barrel 2, and the mold barrel 2 and the front head 3 are assembled;

[0046] Step 3: Pour a certain amount of mixed adhesive 4 into the front head 3, and then vertically place the medicine column 5 from above the mold barrel 2 into the cavity formed by the front head 3 and the mold barrel 2 until the head of the medicine column 5 contacts the annular protrusion 9 on the front head 3;

[0047] Step 4: let it stand for a while, and remove the base 1 and the mold cylinder 2 after the adhesive 4 is cured, so as to obtain a drug column 5 and a front head 3 that are reliably bonded and have the same posture.

[0048] In the above technical scheme, when calculating and determining the amount of adhesive 4, the inner surface of the front head 3 is obtained according to the outer surface of the medicine column 5, and then according to the height of the annular protrusion 9, a cavity is formed between the inner surface of the front head 3, the inner wall of the mold barrel 2 and the outer surface of the medicine column 5, and then the volume of the cavity formed by the inner surface of the front head 3, the inner wall of the mold barrel 2 and the outer surface of the medicine column 5 is obtained by using three-dimensional modeling software such as solidworks, and then the volume of the annular protrusion 9 is subtracted to obtain the amount of adhesive 4, wherein the volume of the annular protrusion 9 is equal to the difference between the volume of a cylinder with the outer wall of the annular protrusion 9 as the radius and the volume of a cylinder with the inner wall of the annular protrusion 9 as the radius, which is also obtained by using three-dimensional modeling software such as solidworks.

[0049] In step three, when the medicine column 5 is vertically placed into the cavity formed by the front head 3 and the mold barrel 2 from above the mold barrel 2, and the head of the medicine column 5 contacts the annular protrusion 9 on the front head 3, due to the downward extrusion of the medicine column 5, the adhesive 4 on the front head 3 moves radially outward, thereby filling the cavity formed by the medicine column 5, the mold barrel 2, the front head 3 and the annular protrusion 9.

[0050] The grain 5 is a composite propellant with an aspect ratio greater than 7, and the axial lower end of the grain 5 is in a butterfly shape.

[0051] In the above technical solution, when the aspect ratio of the drug column 5 is greater than 7, the thickness of the adhesive 4 (ie, the annular protrusion 9) is generally 2 mm ± 0.2.

[0052] A coating layer 10 is provided on the drug column 5 except its axial upper end surface.

[0053] In the above technical solution, the thickness of the coating layer 10 can be designed according to requirements, and the coating layer 10 plays a role of limiting combustion during the operation of the engine.

[0054] The coating layer 10 is made of EPDM rubber.

[0055] In the above technical solution, EPDM rubber can meet the process requirements.

Claims

1. A device for bonding free-loading charge in an engine casing, characterized in that: The invention comprises a base (1), wherein the base (1) is provided with a mounting hole (6), wherein a mold barrel (2) and a front head (3) are provided in the mounting hole (6), and a cavity is formed between the front head (3) and the mold barrel (2); an annular protrusion (9) is provided on the inner wall of the front head (3); an adhesive (4) is provided on the upper surface of the front head (3), and the amount of the adhesive (4) is equal to the difference between the volume of a cavity formed by the inner surface of the front head (3), the inner wall of the mold barrel (2) and the outer surface of the drug column (5) and the volume of the annular protrusion (9); and the thickness of the adhesive (4) is the same as the height of the annular protrusion (9).

2. The device for bonding free-loading charge in an engine casing according to claim 1, characterized in that: A limiting step (7) is provided on the inner wall of the bottom of the mold barrel (2), and the inner wall of the limiting step (7) is fixedly connected to the outer wall of the front sealing head (3).

3. The device for bonding free-loading charge in an engine casing according to claim 1, characterized in that: The inner wall of the limiting step (7) and the outer wall of the front head (3) are threadedly connected.

4. The device for bonding free-loading charge in an engine casing according to claim 1, characterized in that: A limiting convex ring (8) is arranged on the outer wall of the mold cylinder (2).

5. The device for bonding free-loading charge in an engine casing according to claim 1, characterized in that: The mounting hole (6) of the base (1) and the mold cylinder (2) are threadedly connected.

6. The device for bonding free-loading charge in an engine casing according to claim 1, characterized in that: The adhesive (4) is a two-component epoxy resin adhesive.

7. A process for bonding free-loading grains in an engine casing, characterized in that: The device for bonding free-loading charge in an engine casing according to any one of claims 1 to 6 comprises the following steps: Step 1, determining the type of the drug column (5), determining the inner diameter and length of the mold barrel (2) according to the outer diameter and length of the drug column (5), and determining the inner profile of the front head (3) according to the head profile of the drug column (5); Step 2: according to the inner diameter of the mounting hole (6) determined by the outer diameter of the mold barrel (2), the mold barrel (2) and the base (1) of the front head (3) are connected to the mold barrel (2), and the mold barrel (2) and the front head (3) are assembled; Step 3: Pour a certain amount of mixed adhesive (4) into the front head (3), and then vertically place the medicine column (5) from the top of the mold barrel (2) into the cavity formed by the front head (3) and the mold barrel (2) until the head of the medicine column (5) contacts the annular protrusion (9) on the front head (3); Step 4: let it stand for a while, and after the adhesive (4) is solidified, remove the base 1 and the mold cylinder (2), so as to obtain a drug column (5) and a front head (3) that are reliably bonded and have the same posture.

8. The process for bonding free-loading charge in an engine casing as claimed in claim 7, characterized in that: The grain (5) is a composite propellant with an aspect ratio greater than 7, and the axial lower end of the grain (5) is in a butterfly shape.

9. The process for bonding free-loading grains in an engine casing as claimed in claim 7, characterized in that: The medicine column (5) is provided with a coating layer (10) except for its axial upper end surface.

10. The process for bonding free-loading grains in an engine casing as claimed in claim 9, characterized in that: The coating layer (10) is EPDM rubber.

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