Method for designing shape of rubber winding forming compression roller
Technical Field
The invention belongs to the technical field of rubber winding forming, and relates to a design method for a shape of a compression roller formed by winding a heat insulating layer of a solid rocket engine.
Background
At present, the shell of the solid rocket engine is generally manufactured by adopting a method of winding an ethylene propylene diene monomer rubber heat insulation inner layer and a composite material on a shell for molding. The method for forming the ethylene propylene diene monomer heat insulation layer mainly comprises a manual surface mounting method and a winding forming method. In the winding and forming process of the heat insulating layer of the solid rocket engine, the ethylene propylene diene monomer rubber tape is heated to improve the self-adhesive property, the tape is wound on the core mold by using the winding compression roller, and the winding pressure directly influences the appearance of the heat insulating layer and the bonding strength and the density of the heat insulating layer. Because the surfaces of the winding core mold and the rubber heat insulation layer are variable curvature curved surfaces, in order to ensure that the winding pressure in the width direction of the adhesive tape is uniformly and constantly distributed, the appearance of the winding compression roller needs to be reasonably designed.
A hot-pressing roller device for a cloth tape winding machine is disclosed in 'a hot-pressing roller device for a cloth tape winding machine' of Penjiahao (CN202716461U), and the device comprises a hot-pressing roller body, a central shaft, an electric heating pipe and a bush, mainly relates to a hot-pressing roller structure and does not relate to the shape design of a pressing roller. Zhanjun discloses a hot press roll device for a composite material tape winding machine in a patent 'the press roll device for the composite material tape winding machine' (CN103909649A), mainly relates to a hot press roll structure for automatically scraping molten glue of a press roll, and does not relate to the appearance design of the press roll.
In the automatic winding process of the heat insulation layer of the cylinder section of the solid rocket engine, if the winding compression roller is in a simple cylindrical surface shape, when the circular winding is performed, the distance between the winding compression roller in the width direction of the adhesive tape and the shape of the core mold (or the shape of the heat insulation layer) is inconsistent, the distance between the edge part of the adhesive tape is large, the winding pressure is small, the winding quality and the bonding quality are influenced, and even the edge warping phenomenon appears on two sides of the wound adhesive tape, so that the shape of the winding compression roller needs to be reasonably designed.
Disclosure of Invention
The invention provides a method for designing the shape of a rubber winding forming press roller, which is used for designing the shape of the rubber winding press roller.
The technical scheme adopted by the invention is as follows:
a method for designing the shape of a rubber winding forming compression roller comprises the following steps:
(1) calculation of the winding angle α:
the winding angle alpha is an included angle between the central line of the rubber adhesive tape 1 and the axis of the core mold, C is the perimeter of the core mold, W is the width of the rubber adhesive tape, and R is the radius of the core mold. Wherein the ratio of W to C is the cosine of the winding angle, from which the winding angle α is calculated as:
α=arccos(W/C)....................................................①
C=2πR....................................................②
(2) calculating the ellipse equation of the core model on the section B-B:
the tape winding is carried out along the direction which forms an included angle alpha with the axis of the core mould, the direction is the winding spiral line direction A-A, the surface B-B is a vertical section of A-A, the core mould is an ellipse on the section B-B, and the ellipse equation is as follows:
cos2αx2+y2=R2....................................................③
substituting the formula II into the formula III to obtain:
wherein: x and y are respectively the horizontal and vertical coordinates of the points on the ellipse.
The position relations of the core die, the winding compression roller and the rubber adhesive tape in the B-B section are as follows: and the rubber adhesive tape is wound on the core mold along the direction which forms an included angle alpha with the axis of the core mold under the action of the winding compression roller.
(3) And (3) constructing an elliptic revolution surface of the winding press roller by taking the elliptic equation (r) determined in the step (2) as a bus and the axis 4 of the winding press roller 3 as a revolution center line, and finishing the appearance design of the rubber winding press roller.
The invention has the beneficial effects that: the shape of the rubber winding compression roller adopts an elliptical line as a bus structure to wind the rotary concave surface of the compression roller, so that the winding pressure can be reduced, the winding pressure is uniformly distributed along the width direction of the adhesive tape, the winding pressure and the winding quality of the edge of the adhesive tape are improved, and the phenomenon of edge warping on two sides of the adhesive tape is avoided; meanwhile, the elliptical revolution surface of the winding pressing roller can improve the stability of the adhesive tape in the winding process. The rubber winding compression roller designed by the method is suitable for the requirement of circumferential winding of the heat insulating layer of the cylinder section and the transition parts at two ends of the solid rocket engine. The shape of the rubber winding compression roller is designed by adopting the minimum diameter model in the models of the solid rocket engines, so that the automatic winding requirement of rubber heat insulating layers at the cylinder sections of the solid rocket engines of different models can be met.
Drawings
Fig. 1 is a schematic diagram of rubber hoop winding, wherein: 1 is rubber adhesive tape, alpha is winding angle, W is adhesive tape width, C is mandrel circumference, A-A is winding helix direction, B-B is A-A winding helix direction vertical section.
Fig. 2 is a schematic diagram of the positional relationship between the core mold, the winding pressure roller and the rubber tape on the B-B surface, wherein: 1 is rubber adhesive tape, 2 is an elliptical line on the section of the core mold B-B, 3 is a winding compression roller, 4 is the axis of the winding compression roller, h is the thickness of the adhesive tape, L is the length of the winding compression roller, and R is the radius of the core mold.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
The embodiment relates to a method for designing the shape of a pressing roller formed by winding a heat insulating layer of a solid rocket engine, which comprises the following steps:
in this embodiment, the core mold diameter ranges for different solid rocket engine models are: 480mm-2000mm, selecting the minimum model core die with the diameter of 480mm to design the shape of the winding roller, wherein the radius R of the core die is 240mm, and the width W of the adhesive tape is 100 mm.
(1) As shown in fig. 1 and 2, the winding angle α is calculated from the rubber tape width W and the core mold radius R as:
C=2πR....................................................①
α=arc cos(W/C)....................................................②
i.e., C1507.20 mm and α 86.20 °.
(2) As shown in fig. 1, the tape winding is performed along the direction of the winding angle α (counterclockwise rotation along the core mold axis) from the core mold axis, which is the vertical section of the winding helix direction a-a, and the plane B-B is a-a, the positional relationship of the core mold, the winding pressure roller, and the rubber tape in the section B-B is shown in fig. 2, and the core mold has an ellipse 2 on the section B-B, which is the equation:
cos2αx2+y2=R2...............................................③
(3) and (4) constructing an elliptic revolution surface of the winding press roller by taking an elliptic equation (r) as a bus and the axis 4 of the winding press roller as a revolution center line, and finishing the appearance design of the rubber winding press roller.
Obtaining a rotary generatrix expression of the winding compression roller according to the calculation, wherein the axial length of the winding compression roller is 1-2mm longer than the width of the adhesive tape, namely:
the winding pressure roller is taken as a winding pressure roller rotating bus, and the winding pressure roller axis 4 is taken as a rotating center line, so that the appearance of the winding pressure roller can be constructed.
The above-mentioned embodiments only express the embodiments of the present invention, but not should be understood as the limitation of the scope of the invention patent, it should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the concept of the present invention, and these all fall into the protection scope of the present invention.