Solid propellant filtering and degassing pattern plate

Abstract

The utility model provides a solid propellant filtering and degassing tubesheet. The solid propellant filtering and degassing tubesheet comprises a tubesheet main body and blanking holes, the tubesheet main body is a wood circular plate, and blanking holes are distributed on the tubesheet main body; when a solid propellant is poured into the engine shell, the blanking holes are uniformly distributed in the whole area of the pattern plate main body; when a solid propellant square billet is poured, the discharging holes are distributed in the middle of the pattern plate body in a matrix mode. Aiming at the solid propellant pouring or solid propellant square billet pouring of an engine shell, the filtering and degassing pattern plate with different blanking hole distribution is adopted, so that the forming efficiency of a solid propellant in a specific shape after filtering and degassing is improved; by adopting the wood structure, the cost is low, the device can be used as a single-use product, the problem that a traditional metal pattern plate is difficult to clean is solved, the direct contact time of personnel and a propellant is shortened, and the safety risk is reduced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the solid propellant pouring pre -treatment technical field especially relates to a kind of solid propellant filtering degassing flower plate. BACKGROUND

[0002] In the preparation process of solid propellant, the flower plate is used as a key component to filter the pores in the slurry, and its filtering effect directly affects the product quality. The solid propellant grain requires complete structure, and the surface and interior of the grain must not have pores, cracks and sponge-like loose structure, otherwise it will affect the interior ballistic characteristics of the engine, and in severe cases, it will cause the engine to explode. Under vacuum casting conditions, the propellant slurry is dispersed into many thin strips by the flower plate, which is used to discharge the gas mixed in the propellant slurry, and then poured into the combustion chamber, so as to minimize the pores in the prepared grain. After each pouring is completed, the operator needs to clean the used metal flower plate for a long time in order to be reused next time.

[0003] Currently, stainless steel and other metal materials are mainly used for the production and selection of the flower plate. Although the quality is excellent, when facing the flower plate with small holes and large quantity, the cleaning difficulty is great, the time is long, and the personnel need to contact the propellant for a long time during the cleaning process, which has high safety risk. In addition, the cost of metal material is high, which is not conducive to cost control. At the same time, the degassing effect and efficiency of the current flower plate still need to be improved. UTILITY MODEL CONTENT

[0004] In order to overcome the deficiencies in the prior art, the present inventors have made intensive research and provided a solid propellant filtering degassing flower plate, which optimizes the design of the flower plate structure, improves the degassing effect and efficiency of the flower plate, and overcomes the problems of cost and operation safety.

[0005] The technical scheme provided by the utility model is as follows:

[0006] A solid propellant filtering degassing flower plate, comprising a flower plate body and a discharging hole; the flower plate body is a wooden circular plate with discharging holes distributed thereon; for pouring solid propellant into the engine shell, the discharging holes are uniformly distributed in the overall area of the flower plate body; for pouring solid propellant into the square billet, the discharging holes are arranged in a matrix in the middle of the flower plate body.

[0007] Further, for pouring solid propellant into the engine shell, the discharging holes are arranged in concentric rings on the flower plate body, and the hole diameter of the discharging holes arranged in rings gradually decreases from the outer ring to the inner ring.

[0008] Further, for pouring solid propellant into the engine shell, the outermost discharging hole is the first circle of discharging holes, the hole diameters of the odd-numbered circle of discharging holes are the same, the hole diameters of the even-numbered circle of discharging holes are the same, and the hole diameters of adjacent circles of discharging holes are different.

[0009] Further, the blanking holes are distributed on the flower plate body in concentric circles or concentric hexagons.

[0010] Further, the blanking holes on the filter degassing flower plate are arranged in a matrix and have the same diameter.

[0011] Further, the blanking holes are smoothly connected with the two side plates.

[0012] Further, the total area of the blanking holes of the flower plate satisfies W > F, wherein W is the maximum pressure that the flower plate can withstand, and F is the pressure of the flower plate in the environment of uniform blanking and vacuumizing.

[0013] wherein W = σ x A 实 ; σ is the tensile strength of the wooden flower plate, A 实 = A - A 孔 , A is the area of the flower plate, A 实 is the actual force area of the flower plate, and A 孔 is the total area of the blanking holes of the flower plate. N is the number of blanking holes, and d 孔 is the diameter of the blanking holes.

[0014] F = F 真空 + F 药浆 , F 药浆 = P 料 x A 孔 , F 真空 = ΔP x A 实 ,

[0015] ΔP = P a - P 真空 ; P 料 is the pressure of the slurry, ρ is the density of the slurry, g is the acceleration of gravity, v is the flow rate of the slurry, H is the height of the slurry, P 真空 is the vacuum degree, and P a is the atmospheric pressure.

[0016] The solid propellant filter degassing flower plate has the following beneficial effects:

[0017] (1) The solid propellant filter degassing flower plate provided by the utility model is used for solid propellant pouring of an engine shell or solid propellant billet pouring, adopts a filter degassing flower plate with different blanking hole distribution, and improves the forming efficiency of a specific shape solid propellant after filter degassing.

[0018] (2) The solid propellant filter degassing flower plate provided by the utility model adopts a design that the blanking hole diameter gradually decreases from the outer circle to the inner circle or the large hole and the small hole are arranged at intervals, and improves the filter degassing efficiency.

[0019] (3) The solid propellant filter degassing plate provided by this utility model has a smooth transition between the two ends of the discharge hole and the two side plates, which reduces the filtration resistance and improves production safety.

[0020] (4) The solid propellant filter degassing tube sheet provided by this utility model adopts a wooden structure and a low-cost special tube sheet design. It can be used as a single-use product, avoiding the problem of traditional metal tube sheets being difficult to clean, reducing labor costs and cleaning risks; reducing the direct contact time between personnel and propellant, reducing safety risks; the cost of wood material is lower than that of metal materials, which is conducive to reducing production costs; wood is derived from renewable resources and meets environmental protection requirements; wood is easy to process and shape, and the design is flexible and can be quickly adjusted according to actual needs. Attached Figure Description

[0021] Figure 1 A schematic diagram of a solid propellant filter degassing plate;

[0022] Figure 2 A schematic diagram of a solid propellant filtration and degassing tube sheet. Detailed Implementation

[0023] The features and advantages of this utility model will become clearer and more explicit through the following detailed description.

[0024] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0025] This utility model provides a solid propellant filter degassing plate, installed at the discharge port position of the casting cylinder head (i.e., below the discharge valve); such as Figure 1 and Figure 2 As shown, it includes a tube sheet body 1 and discharge holes 2; the tube sheet body 1 is a wooden circular board with discharge holes 2 distributed on it. When pouring solid propellant for the engine casing, the discharge holes 2 are evenly distributed throughout the entire area of ​​the tube sheet body 1; when pouring solid propellant billets, the discharge holes 2 are arranged in a matrix in the middle of the tube sheet body 1.

[0026] To reduce filtration resistance, the two ends of the discharge hole 2 are smoothly transitioned to the two side plates.

[0027] The pressure of the perforated board under a vacuum environment with uniform material feeding is F = F 真空 +F 药浆 The pressure that the tube sheet withstands in a vacuum environment is F. 真空 =ΔP×A 实 Where ΔP=P a -P真空 P 真空 For vacuum degree, P a At atmospheric pressure, A 实 A represents the actual load-bearing area of ​​the perforated board. 实 =AA 孔 A is the area of ​​the perforated plate. 孔 This represents the total area of ​​the material feeding holes in the tube sheet. N is the number of feed holes, d 孔 This refers to the diameter of the feed hole.

[0028] The pressure of the slurry that the tube sheet experiences during the uniform feeding process is F. 药浆 =P 料 ×A 孔 ;where P 料 For the pressure of the slurry, according to Bernoulli's theorem Where ρ is the density of the slurry, g is the acceleration due to gravity, v is the flow velocity of the slurry, and H is the height of the slurry.

[0029] The maximum pressure that the perforated plate can withstand is W = σ × A 实 Where σ is the tensile strength of the wooden panel, which is related to the material.

[0030] Based on W>F, determine the allowable number of feed holes N and the feed hole diameter d of the tube sheet. 孔 .

[0031] Assume the density ρ of the solid propellant slurry is 1.6–1.8 g / cm³. 3 The acceleration due to gravity g is 9.8 m / s². 2 The slurry height H is 0.407m, the vacuum degree P inside the casting cylinder is 100Pa~400Pa, and the standard atmospheric pressure is 101.325kPa. A specially designed perforated plate is used for the casting gate size of the small billet. The perforated plate has a diameter of 102mm and a thickness of 3mm. The average flow velocity v of the slurry flowing through the discharge holes of the perforated plate is 0.0025m / s. To ensure stable discharge during the casting process, small holes with a diameter of 4mm are designed, arranged in an array of 3 columns and 10 rows, with a 4mm interval between the discharge holes, for a total of 30 discharge holes. The strength of the wooden perforated plate is σ. (The number of discharge holes needs to be designed based on the flowability of the solid propellant slurry and the mechanical properties of the propellant.)

[0032] 1. Calculate the effective area of ​​the perforated plate. Given that the diameter of the perforated plate is d = 102 mm = 0.102 mm, and π is taken as 3.14, substituting into the following formula, we get its area as 8.17 × 10⁻⁶. -3 m 2 for:

[0033]

[0034] Feed hole diameter d 孔=4mm=0.004m, the area of ​​each feed hole There are a total of 30 feeding holes, and the total area of ​​the feeding holes is A. 孔 =30 × 1.26 × 10 -5 =3.78×10 -4 m 2 The actual load-bearing area A of the perforated board. 实 =AA 孔 =7.79×10 -3 m 2 .

[0035] 2. Pressure of the tube sheet under vacuum conditions with uniform material feeding.

[0036] When the vacuum degree P 真空 =300Pa, Pressure F 真空 =Δ×P 实 = (101325-300)×7.79×10 -3 = 786.985N; when the vacuum degree P 真空 When the pressure F is 400 Pa, 真空 = (101325-400)×7.79×10 -3 =786.206N.

[0037] The density ρ of the solid propellant slurry is known to be 1.6–1.8 g / cm³. 3 Converted to kg / m 3 1600~1800kg / m 3 According to Bernoulli's theorem Calculate The pressure F of the slurry that the tube sheet experiences during the uniform feeding process. 药浆 =P 料 ×A 孔 =7179.48 × 3.78 × 10 -4 =2.692N.

[0038] The pressure of the tube sheet under a vacuum environment with uniform material feeding is F = F1 + F 药浆 =789.677N.

[0039] 3. Calculate the maximum pressure that the tube sheet can withstand.

[0040] Given that the compressive strength σ of the (basswood) veneer is 0.15 MPa, convert it to N / m. 2 0.15×10 6 N / m 2 Based on the tensile or compressive strength σ of the wooden panel (selected according to the stress conditions), the pressure it can withstand is:

[0041] W = σ × A 实

[0042] Calculated using Formula 2, W = 0.15 × 10 6 ×7.79×10 -3 =1168.5N, which can verify the safety and reliability of wooden panels under specific working conditions.

[0043] Based on the above calculations, W>F, indicating that the tube sheet can be used safely under the existing vacuum conditions.

[0044] In a preferred embodiment, when pouring solid propellant into the engine casing, the discharge holes 2 are arranged in a concentric ring on the main body 1, such as concentric circles or concentric hexagons; the diameter of the discharge holes gradually decreases from the outer ring to the inner ring. The solid propellant experiences greater viscous resistance during flow in the outer ring, and air bubbles are gradually discharged during the flow process, so the outer ring discharge holes can be relatively large to accommodate the flow resistance; the solid propellant in the central region has a faster flow rate and contains more air bubbles, so smaller vent holes are designed to ensure sufficient venting.

[0045] Alternatively, when casting solid propellant into the engine casing, the outermost feed hole is designated as the first feed hole. Odd-numbered feed holes have the same diameter, even-numbered feed holes have the same diameter, and adjacent feed holes have different diameters. The different diameters of adjacent feed holes cause the solid propellant on the same cross-section to pass through the perforated plate asynchronously, which facilitates the removal of pores from the solid propellant.

[0046] In a preferred embodiment, when casting solid propellant billets, the diameters of the feed holes 2 arranged in the matrix are the same.

[0047] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and implementation methods of the present invention without departing from the spirit and scope of the present invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

[0048] The contents not described in detail in this utility model specification are common knowledge to those skilled in the art.

Claims

1. A solid propellant filter degassing plate, characterized in that, It includes a tube sheet body and discharge holes; the tube sheet body is a wooden circular board with discharge holes distributed on it; when pouring solid propellant for the engine casing, the discharge holes are evenly distributed throughout the entire area of ​​the tube sheet body; when pouring solid propellant billets, the discharge holes are arranged in a matrix in the middle of the tube sheet body.

2. The solid propellant filter degassing plate according to claim 1, characterized in that, When pouring solid propellant into the engine casing, the discharge holes are arranged in a concentric ring on the tube sheet body, and the diameter of the discharge holes gradually decreases from the outer ring to the inner ring.

3. The solid propellant filter degassing plate according to claim 1, characterized in that, When pouring solid propellant into the engine casing, the outermost discharge hole is taken as the first discharge hole. The discharge holes of odd-numbered rings have the same diameter, the discharge holes of even-numbered rings have the same diameter, and the discharge holes of adjacent rings have different diameters.

4. The solid propellant filter degassing plate according to claim 2 or 3, characterized in that, The feeding holes are distributed on the main body of the tube sheet in concentric circles or concentric hexagons.

5. The solid propellant filter degassing plate according to claim 1, characterized in that, When casting solid propellant billets, the diameter of the discharge holes arranged in a matrix on the filter degassing plate is the same.

6. The solid propellant filter degassing plate according to claim 1, characterized in that, The two ends of the feeding hole smoothly transition to the two side plates.

7. The solid propellant filter degassing plate according to claim 1, characterized in that, The total area of ​​the material feeding holes of the tube sheet satisfies: W>F, where W is the maximum pressure that the tube sheet can withstand, and F is the pressure of the tube sheet under a vacuum environment with uniform material feeding. Where W = σ × A 实 σ represents the tensile strength of the wooden panel, and A represents the tensile strength of the panel. 实 =AA 孔 A is the area of ​​the perforated plate. 实 A represents the actual load-bearing area of ​​the perforated board. 孔 This represents the total area of ​​the material feeding holes in the tube sheet; N is the number of feed holes, d 孔 The diameter of the feeding hole; F=F 真空 +F 药浆 ,F 药浆 =P 料 ×A 孔 , F 真空 =ΔP×A 实 , ΔP=P a -P 真空 ;P 料 ρ is the slurry pressure, ρ is the slurry density, g is the acceleration due to gravity, v is the slurry velocity, H is the slurry height, and P is the slurry pressure. 真空 For vacuum degree, P a Atmospheric pressure.

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