KR101846635B1 - A base bleed unit comprising the insulation and method of manufacturing the same - Google Patents

Abstract

The present invention relates to a drag reducing agent including a heat resistant material, and more particularly to a drag reducing agent containing natural rubber or synthetic rubber as the heat resistant material and further containing an additive.

Description

TECHNICAL FIELD The present invention relates to a drag reducing agent including a heat resistant material and a method for manufacturing the same,

TECHNICAL FIELD The present invention relates to a drag reducing agent including a heat resistant material, and more particularly to a drag reducing agent including natural rubber or synthetic rubber as a heat resistant material.

The liner is a resilient rubber material and is present in a case-bonded rocket propulsion engine with a solid propellant bonded to the combustion tube at a thickness of about 0.5 to 3 mm outside the propellant on the combustion tube. The liner protects the propellant grain during storage and transport of the propulsion machinery, adjusts the combustion area of the propellant, and protects the combustion tube from heat during combustion.

In order for the liner to function as described above, the adhesion between the liner and the propellant plays the most important role, but the conventional liner has many problems.

As a result of the above problems, it is possible to obtain a polyurethane resin having a molecular weight of about 150 to 250 g / mol such as toluene-2,4-diisocyanate (TDI), dimeryl diisocyanate (DDI) and isophorone diisocyanate This small curing agent is used for the liner, and there is a problem that the curing agent of the liner penetrates into the inside during the curing process.

Also, there is a problem that the moisture moves to the liner and the propellant and the adhesion of the liner and the propellant is weakened.

In order to solve the above problems, a material transfer inhibitor such as 4,4,4-triphenylmethane triisocyanate (Desmodur RE) is applied to the interface, the liner is poured to harden, the propellant is filled and cured However, in order to produce such a propulsion engine, a process of applying a substance transfer inhibitor is required, and there is a possibility of contamination during operation.

In addition to the above adhesion problems, many steps are required to manufacture the liner. Specifically, many process steps are required, such as raw material preparation, metering, raw material mixing, filling of mixed liner, curing, release after curing and finishing. Further, in order to form a liner on the outer surface of the propellant, a liner mold, a jig preparation, a granulation process, and the like are required. After the liner is cured, a mold and a jig dismantling process are additionally required.

Due to the above-mentioned many process steps, a lot of personnel and a large amount of chemical agents are stagnated in the manufacturing room at the time of manufacturing the liner, which may cause safety and risk problems, which is not economical.

Liners used in conventional drag reducing agents require many raw materials and require many process steps such as raw material preparation, metering, raw material blending, mixed liner filling, hardening, curing, release and finishing, and are unproductive .

As a result, a large number of personnel are required in the production hall for manufacturing the liner, and a large amount of chemical agents are stagnant, which may cause safety and risk problems.

Accordingly, in order to solve the conventional problems,

Instead of a liner, it is intended to use a heat-resistant material which is manufactured from a small amount of raw material, has a simple manufacturing process, and has excellent properties.

That is, the object of the present invention is to provide a drag reducing agent comprising a solid propellant and a heat resistant material.

The present invention also aims at providing a method for producing the drag reducing agent.

In order to achieve the above object,

The present invention relates to a drag reducing agent comprising a cylindrical solid propellant and a heat resistant material wrapping around the cylindrical solid propellant,

Wherein the heat resistant material comprises natural rubber or synthetic rubber.

Further, the present invention is a method for manufacturing a drag reducing agent characterized by assembling a heat resistant material which surrounds a cylindrical solid propellant,

The heat resistant material is natural rubber or synthetic rubber.

The drag reducing agent including the solid propellant and the heat resistant material of the present invention can reduce the manufacturing time and the production force by simplifying the complicated manufacturing process of the liner by using the heat resistant material instead of the conventional liner, .

Further, the drag reducing agent of the present invention has heat resistance effect of high strength and high elasticity.

In addition, the drag reducing agent of the present invention can reduce the amount of gunpowder stagnation during the manufacturing process, thereby enhancing safety.

FIG. 1 is a photograph showing the structure of the shell. FIG.
2 is a drag reducing agent structure of the present invention.
3 is a photograph showing a manufacturing process of a drag reducing agent including the heat resistant material of the present invention.
4 is a photograph showing a manufacturing process of a drag reducing agent including a conventional liner.
5 is a photograph of a drag reducing agent including a heat resistant material.
Figure 6 is a photograph of a drag reducing agent comprising a liner.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a drag reducing agent comprising a cylindrical solid propellant and a heat resistant material wrapping around the cylindrical solid propellant,

The heat resistant material is characterized by comprising natural rubber or synthetic rubber.

Conventional drag reducing agents included solid propellants and liner.

The drag reducing agent has a cylindrical shape, a solid propellant is located at the center, and the outer periphery of the solid propellant surrounds the liner with a thickness of 1.5 to 2 mm.

However, the liner requires more than seven kinds of raw materials and many process steps such as metering of the raw materials, raw material blending, mixed liner filling, hardening, curing, releasing and finishing are required, It was difficult to do.

In addition, a large number of production personnel are required for liner manufacturing, and a large number of chemical agents are stagnant, which is likely to cause safety and risk issues.

Accordingly, in order to solve the above problems, the present invention provides a drag reducing agent including a solid propellant and a heat resistant material by using a simple heat resistant material instead of a liner.

In the present invention, the type of the solid propellant is not particularly limited, and those used in the art can be used, but preferably a hydroxyl terminated polybutadiene (HTPB) terminated with a hydroxyl group is used. K310 drag reducing agents used in K9 or K55A1, K307 drag reducing agents and drag reducing agents for high bombardment or dispersed coal use for the development of 155 mm range extension gun systems can be used.

As the heat resistant material of the present invention, natural rubber or synthetic rubber may be used. The synthetic rubber may be an ethylene propylene diene monomer (EPDM), an isobutene isoprene rubber (IIR), an isoprene rubber IR), silicone rubber (SR), and acrylonitrile butadiene rubber (NBR), preferably ethylene propylene diene monomer.

Further, the heat resistant material of the present invention may further include additives, and the additive includes at least one selected from the group consisting of silica (silica), carbon black (carbon black), and Kevlar.

By further including the additive, the heat resistant material can have a tensile strength of 120 to 150 kg / cm ² , an elongation of 500 to 800%, a glass transition temperature of -50 to -70 캜, and a Shore A hardness of 40 to 60, It is possible to have a heat resistance effect of high strength and high elasticity.

The conventional liner does not have the above-mentioned effect, but the heat resistant material of the present invention has the above-mentioned effect, so that a more excellent drag reducing agent can be provided.

The drag reducing agent of the present invention may be a self-contained or cross-linked extended release.

When the drag reducing agent is frequently incorporated, the thickness of the heat resistant material is 1 to 3 mm, preferably 1.5 to 2.5 mm. If the thickness of the heat resistant material is less than 1 mm, the heat resistance is deteriorated. If the thickness is more than 3 mm, the performance of the drag reducing agent is deteriorated.

Further, when the drag reducing agent is a long-range extended-burning type, the thickness of the heat resistant member is 1 to 2.5 mm, preferably 1 to 2 mm. If the thickness of the heat resistant material is less than 1 mm, the heat resistance is deteriorated. If the thickness exceeds 2.5 mm, the performance of the drag reducing agent is deteriorated.

Further, the present invention is a method for manufacturing a drag reducing agent characterized by assembling a heat resistant material which surrounds a cylindrical solid propellant,

Wherein the heat resistant material is natural rubber or synthetic rubber.

In the present invention, the type of the solid propellant is not particularly limited, and those used in the art can be used, but preferably a hydroxyl terminated polybutadiene (HTPB) terminated with a hydroxyl group is used. K310, K307, and 155mm range extension gun systems can be used.

As the heat resistant material of the present invention, natural rubber or synthetic rubber may be used. The synthetic rubber may be an ethylene propylene diene monomer (EPDM), an isobutene isoprene rubber (IIR), an isoprene rubber IR), silicone rubber (SR), and acrylonitrile butadiene rubber (NBR), preferably ethylene propylene diene monomer.

Further, the heat resistant material of the present invention may further include additives, and the additive includes at least one selected from the group consisting of silica (silica), carbon black (carbon black), and Kevlar.

By further including the additive, the heat resistant material can have a tensile strength of 120 to 150 kg / cm ² , an elongation of 500 to 800%, a glass transition temperature of -50 to -70 캜, and a Shore A hardness of 40 to 60, It is possible to have a heat resistance effect of high strength and high elasticity.

The conventional liner does not have the above-mentioned effect, but the heat resistant material of the present invention has the above-mentioned effect, so that a more excellent drag reducing agent can be provided.

The drag reducing agent of the present invention may be a self-contained or cross-linked extended release.

When the drag reducing agent is frequently incorporated, the thickness of the heat resistant material is 1 to 3 mm, preferably 1.5 to 2.5 mm. If the thickness of the heat resistant member is less than 1 mm, heat resistance is deteriorated, and if it exceeds 3 mm, the drag strength reducing agent performance is deteriorated.

Further, when the drag reducing agent is a long-range extended-burning type, the thickness of the heat resistant member is 1 to 2.5 mm, preferably 1 to 2 mm. If the thickness of the heat resistant material is less than 1 mm, the heat resistance is deteriorated. If the thickness exceeds 2.5 mm, the drag strength reducing agent performance deteriorates.

The drag reducing agent is a structure in which a heat resistant material surrounds the outside of the solid propellant. More specifically, the heat resistant material is manufactured in a shape and specification suited to the use of the drag reducing agent through a press molding process using high temperature and high pressure, The heat resistant material can be assembled by covering the outer surface of the solid propellant.

At this time, in order to assemble the heat resistant material to the outside of the solid propellant, it is possible to use an adhesive to the outside of the solid propellant or to assemble without using an adhesive.

In the case of using an adhesive, it is possible to apply the adhesive to the entire outer surface of the solid propellant, or to apply the adhesive only to the upper and lower surfaces of the outer surface of the solid propellant to assemble the heat resistant material. The range of application of the adhesive on the upper surface and the lower surface is limited But it may be 5 to 25 mm, preferably 10 to 20 mm each.

The kind of the adhesive used for assembling the heat resistant material is not particularly limited, and those used in the art can be used. As the product, Araldite or SC 2000 and the like can be used.

The drag reducing agent including the solid propellant and the heat resistant material of the present invention requires a lot of raw materials and uses a heat resistant material produced by a simple process with a small amount of raw material instead of a liner manufactured through complicated process steps to simplify the manufacturing process It is economical and has a safe effect because it can reduce risk factors in the process.

In addition, the heat resistant material can further increase tensile strength, elongation, glass transition temperature, hardness, etc. by including an additive agent, and can exhibit a heat resistance effect of high strength and high elasticity that the liner does not have, .

In addition, the drag reduction of the present invention including the heat resistant material instead of the liner included in the K310 drag reducing agent, the K307 drag reducing agent and the 155mm slip extension gun used in K9 and K55A1, Can be provided.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are intended to further illustrate the present invention, and the scope of the present invention is not limited by the following examples. The following examples can be appropriately modified and changed by those skilled in the art within the scope of the present invention.

<K310 drag force Reduction agent  Manufacturing>

Example  1 to 6.

A solid propellant for use in K310 using HTPB (Hydroxy Terminated Poly Butadiene) as a binder and DDI (Dimeryl Diisocyanate) as a curing agent was prepared.

Silica and Carbon Black were used as additives, and a heat resistant material having a tensile strength of 120 kg / cm ² or more, elongation of 500% or more, glass transition temperature of -50 ° C or less and Shore A hardness of 40 or more was prepared.

The heat resistant material was manufactured by press molding process of high temperature and high pressure according to the shape and specification of K310, and its thickness was 2 ± 0.5 mm.

The Araldite epoxy adhesive was applied to the outside of the solid propellant or the upper and lower surfaces of the solid propellant at a width of 2.5 mm, and then the heat resistant material was coated on the outside of the solid propellant, followed by curing at room temperature for 3 hours or more A solid propellant and a heat resistant material were adhered to produce a drag reducing agent used in K310.

Or K310 drag reducing agent was prepared by covering the outside of the solid propellant with the heat resistant material without using an adhesive.

The drag reducing agent was subjected to rotary burning test at 10000 rpm at room temperature to measure the burning time.

The antistatic agents of Examples 1 to 6 were prepared by varying the kind of the heat-resistant material, the method of applying the adhesive, and the use of the adhesive, and the manufacturing method and the combustion time are shown in Table 1 below.

division Heat-resistant material Adhesive use Adhesive application method Burning time (s) Example 1 Natural rubber ○ Full application 28 to 33 Example 2 ○ Top and bottom application with a width of 25 mm 28 to 33 Example 3 X - 28 to 33 Example 4 EPDM ○ Full application 28 to 33 Example 5 ○ Apply top and bottom with 25 mm width 28 to 33 Example 6 X - 28 to 33

<K307 drag force Reduction agent  Manufacturing>

Example  7-12.

A solid propellant used in K307 was prepared by using HTPB (Hydroxy Terminated Poly Butadiene) as a binder and DDI (Dimeryl Diisocyanate) as a curing agent.

Silica and Carbon Black were used as additives, and a heat resistant material having a tensile strength of 120 kg / cm ² or more, elongation of 500% or more, glass transition temperature of -50 ° C or less and Shore A hardness of 40 or more was prepared.

The heat resistant material was manufactured by press molding process of high temperature and high pressure according to the shape and specification of K307, and the thickness was 1.5 ± 0.5 mm.

The Araldite epoxy adhesive was applied to the outer surface of the solid propellant or the upper surface and the lower surface of the solid propellant at a width of 25 mm, and then the heat resistant material was coated on the outer surface of the solid propellant, followed by curing at room temperature for 3 hours or longer, A propellant and a heat resistant material were bonded to produce a drag reducing agent used in K307.

Or K307 drag reducing agent was prepared by covering the outside of the solid propellant with the heat resistant material without using an adhesive.

The drag reducing agent was subjected to rotary burning test at 10000 rpm at room temperature to measure the burning time.

The anti-drag reducing agents of Examples 7 to 12 were prepared by varying the kind of the heat resistant material, the method of applying the adhesive, and the use of the adhesive. The manufacturing method and the burning time are shown in Table 2 below.

division Heat-resistant material Adhesive use Adhesive application method Burning time (s) Example 7 Natural rubber ○ Full application 27 to 31 Example 8 ○ Apply top and bottom with 25 mm width 27 to 31 Example 9 X - 27 to 31 Example 10 EPDM ○ Full application 27 to 31 Example 11 ○ Apply top and bottom with 25 mm width 27 to 31 Example 12 X - 27 to 31

<155mm Intersection Extended Charge  Drag Reduction agent  Manufacturing>

Example  13-18.

A solid propellant used for the extension of 155 mm range extension using HTPB (Hydroxy Terminated Poly Butadiene) as a binder and DDI (Dimeryl Diisocyanate) as a hardening agent was prepared.

Silica and Carbon Black were used as additives, and a heat resistant material having a tensile strength of 120 kg / cm ² or more, elongation of 500% or more, glass transition temperature of -50 ° C or less and Shore A hardness of 40 or more was prepared.

The heat resistant material was manufactured by high temperature and high pressure press molding process to meet the shape and specification of 155mm slit extension bullet, and the thickness was 1.5 ± 0.5mm.

The Araldite epoxy adhesive was applied to the outer surface of the solid propellant or the upper surface and the lower surface of the solid propellant at a width of 25 mm, and then the heat resistant material was coated on the outer surface of the solid propellant, followed by curing at room temperature for 3 hours or longer, Propellant and heat resistant material were bonded to each other to produce a drag reducing agent for use in the extension of a 155 mm range extension.

Or the heat resistant material was coated on the outside of the solid propellant without using an adhesive to prepare a drag reducing agent for a long extension of 155 mm.

The drag reducing agent was subjected to rotary burning test at 10000 rpm at room temperature to measure the burning time.

The anti-drag reducing agents of Examples 13 to 18 were prepared by varying the kind of the heat-resistant material, the method of applying the adhesive, and the use of the adhesive, and the manufacturing method and the burning time are shown in Table 3 below.

division Heat-resistant material Adhesive use Adhesive application method Burning time (s) Example 13 Natural rubber ○ Full application 18-22 Example 14 ○ Apply top and bottom with 25 mm width 18-22 Example 15 X - 18-22 Example 16 EPDM ○ Full application 18-22 Example 17 ○ Apply top and bottom with 25 mm width 18-22 Example 18 X - 18-22

The combustion times in the rotary burn test of the drag reducing agent used in the conventional K310, K307 and 155 mm slug extension guns using liners are 28 to 33 seconds, 27 to 31 seconds and 18 to 22 seconds, respectively.

In the results of Tables 1 to 3, the burning time in the rotary burning test of the drag reducing agent for the K310, K307 and 155 mm slip extension coals using the heat resistant material of the present invention is 28 to 33 seconds, 27 to 31 seconds, 22 seconds.

That is, it was found that the drag reducing agent including the heat resistant material instead of the liner of the present invention exhibited the same performance as the conventional one.

In addition, the liner is manufactured through a lot of raw materials and complicated manufacturing steps and is not productive. On the other hand, the heat resistant material can be manufactured in a simple manufacturing process using a small amount of raw material, thereby increasing the economic effect and further improving the stability.

Therefore, the drag reducing agent including the solid propellant and the heat resistant material of the present invention exhibits the effect of high strength and high elasticity while exhibiting the performance equivalent to that of the conventional drag reducing agent, and the economic effect can be increased due to the simple manufacturing process.

Claims (18)

As a drag reducing agent containing a cylindrical solid propellant and a heat resistant material surrounding the outside,
The heat-resisting material includes natural rubber or synthetic rubber,
Silica, carbon black and Kevlar, and has a tensile strength of 120 to 150 kg / cm ² , elongation of 500 to 800%, glass transition temperature of -50 to -70 캜 and Shore A hardness of 40 Lt; RTI ID = 0.0 &gt; 60. &Lt; / RTI &gt;
The anti-drag agent according to claim 1, wherein the synthetic rubber comprises at least one member selected from the group consisting of ethylene propylene diene monomer, isobutene isoprene rubber, isoprene rubber, silicone rubber and acrylonitrile butadiene rubber. delete delete The drag reducing agent according to claim 1, wherein the drag reducing agent is a self-contained or extended range carbon black. The drag reducing agent according to claim 5, wherein the thickness of the heat resistant material of the self-engaging drag reducing agent is 1 to 3 mm. [Claim 6] The drag reducing agent of claim 5, wherein the thickness of the heat resistant material of the drag reducing agent for the range-extending carbon is from 1 to 2.5 mm. A method of manufacturing a drag reducing agent characterized by comprising assembling a heat resistant material that surrounds a cylindrical solid propellant,
The heat resistant material is characterized by being natural rubber or synthetic rubber. The heat resistant material includes at least one additive selected from the group consisting of silica, carbon black and Kevlar, and has a tensile strength of 120 to 150 kg / cm ² , elongation of 500 to 800% Wherein the transition temperature is from -50 to -70 占 폚 and the Shore A hardness is from 40 to 60. The anti-drag reducing agent according to claim 8, wherein the synthetic rubber comprises at least one member selected from the group consisting of ethylene propylene diene monomer, isobutene isoprene rubber, isoprene rubber, silicone rubber and acrylonitrile butadiene rubber. Way. delete delete 9. The method of claim 8, wherein the heat resistant material is shaped by press molding. The method of claim 8, wherein the drag reducing agent is a self-contained or extended range carbon. 14. The method of claim 13, wherein the thickness of the heat resistant material of the self-engaging drag reducing agent is 1 to 3 mm. [Claim 15] The method of claim 13, wherein the thickness of the heat resistant material of the drag strength reducing agent for a slug extension gun is 1 to 2.5 mm. 9. The method of claim 8, wherein the heat resistant material is formed by applying an adhesive to the outside of the solid propellant. 17. The method of claim 16, wherein the application of the adhesive is applied to the outer surface or top and bottom of the solid propellant, respectively, with a width of 5 to 25 mm. [Claim 9] The method of claim 8, wherein the heat resistant material is assembled by covering the solid propellant with the adhesive without applying the adhesive.

Images