SU1411147A1 - Installation for continuous moulding of boards - Google Patents

Abstract

The invention relates to the building materials industry and can be used in the manufacture of products from semi-dry perlite mixtures. The purpose of the invention is to improve the quality of products. The installation contains a forming conveyor with a lamellar chain 1, above which is placed the feeder 3 of the molding mixture and a sealing conveyor with a lamellar chain 4. The forming chamber is limited by the working branches of the conveyors, which form a conical pressing part in the area of the support rollers 6 and in the area of the support rollers 7 - calibrating part. The required pressure drop 9 in the mixture when it passes from the pressing part to the calibrating part is achieved by reducing the stiffness of the support rollers 7 of the calibrating part of the shaping chamber, determined from the ratio. Cheni El, X P, MOIKC f2Ep. (31-4c) .. with -N / f6ho P c c.Kc (l-K) -Ep. X К it -Pmaa.c ((lJv) J, where EI is the rigidity of the support roller in the calibrating part of the molding chamber; Ep is the elastic modulus of the compacted mixture; 1 is the distance between the roller supports; c is the coordinate of the support of the working branch of the conveyor to the support roller ; Sf, is the working surface area of the conveyor, reduced to a single support roller; K 0.05-0.3 - pressure drop ratio at the outlet of the molding chamber; max maximum pressing pressure; hj, - thickness of the pressed product; 1 - length of the calibrating part molding chamber; v - pressing speed;, S to 8, fasting nnye coefficients characterizing the deformation properties of the mixture. 2 yl. § (A vj

Description

The invention relates to industrial building materials and can be used in the manufacture of products from semi-dry perlite mixtures.

The purpose of the invention is to improve the quality of products.

FIG. 1 depicts the proposed, installation, general view; in fig. 2 - reading A-A in FIG. 1,

I The dp installation of continuous molding of plates contains a forming trans- porter in the form of a lower drive plate 5, chain 1, which is covered by a conveyor belt 2. Above it are located the feeder 3 of the molding sand and the sealing conveyor in a kind of stale chain 4 with conveyor belt 20 5, the forming chamber is limited by the working branches of conveyors, plates ™ chains 1 and 4 of which in the area of the support rollers 6 an image conical pressing hour TV ,; and in the support zone

rollers 7 - calibrating part. ; The pressing force is transmitted I cut ribs 8, which is provided with each of the plates 9 of the lamellar chains, to the support rollers 6 of the conical compression section 30 and to the support rollers 7 of the calibrating part of the molding chamber. The rigidity of the support rollers b is greater than the rigidity of the support rollers 7 and It is designed for the maximum pressure of 35 extrusions achieved in. pressing part, Reduced stiffness, support rollers 7 can be achieved - by reducing their diameter or wall thickness. The stiffness of the support rollers 7 is selected from the following conditions. It has been established that in the form of loose bulk non-plastic mixtures, for example, semi-dry, perlite masses, on forming installations, c. 45 gauge zone limited,

cracks appear on the surface of the sintered body caused by

five

R

 5 20

25

sharp pressure drops compressing the mixture at the outlet of the press.

It has been established experimentally that when the compacted mixture is aged in the calibrating part of the molding chamber, the occurrence of cracks ceases. At the same time, the pressure of the mixture in the calibrating zone drops to a value (0.05-0.3). The pressure drop in the gauge of the lean zone is caused by two reasons. When the plate 9 is transferred from the support rollers 6 to the support rollers 7, which have a lower stiffness, the mixture is compressed due to the elastic deformation and expands. The support rollers 7 at the same time bend by the magnitude of UX, and the pressure in the calibrating zone drops. Further, due to the elastic deformations of the mixture, it shrinks by Y, which leads to a further drop in pressure. The pressure distribution along the caliber length can be determined by solving the system of equations

 max 9

2 YX + Yt

(one)

Y, - | l (31--4c) .p ,. (2)

Y in h McfKC fic n fnx 0 6 e .--. (3)

J-, X

V

Equation (I) is an expression of the deformation of the elastic aftereffect of the compacted mixture, equation (2) is the deflection of the support roller 7 under the action of pressure forces Pn, equation (3) is an expression of the magnitude of the elastic deformation of the OA mixture,

Polaga R P, KP „, and solving the system of equations for the stiffness of the rollers EIjj 9 get

Ei - 2Ej: J31-4c) .Spp c. K. Rmaco, p-K) -E

,

p-Rll ". s (1 + K)

EI,

- rigidity of the support roller in the calibrating part - the molding chamber,

- modulus of elasticity of compacted mixture, kgf / cm;

c. K. Rmaco

,

p-Rll ".s (1 + K) - At

distance between roller supports, cm; coordinate of the support working in the conveyor belt on the support roller, cm;

h

- the area of the working surface of the conveyor, reduced to one support roller,

, 05-0.3 is the ratio of the pressure drop at the outlet of the molding chamber;

bruise maximum pressing pressure, kgf / cm; - thickness of the pressed product, cm; 1 - gage length

molding chambers, cm; V is the pressing speed,

cm / min; . .

S and: S are the constant coefficients characterizing the deforming properties of the mixture. The installation works as follows.

The raw material mixture flows from the feeder 3 to the conveyor belt with a backfill thickness h. Through the conveyor belt 2, the mixture enters the conical section, where it is compacted to a thickness hg. When the plate 9 passes from the subsequent support roller 6 of the conical pressing part to the first support roller 7 of the calibrating part, the mixture is expanded under the effect of EI,

2E (.- (31-4c) S

6h

MOI ((

de Ely is the rigidity of the support roller in the calibrating part of the molding chamber, cm; 40

Ep is the modulus of elasticity of the compacted mixture, kgf / cm;

1 - distance. Between roller supports, cm;

C is the coordinate of the support of the working 45 branch of the conveyor to the reference roll, cm; - the area of the working surface of the conveyor, with -.

f

Vedna to one basic roller,

action of the forces of elastic aftereffect. In this case, the support roller 7 bends by an amount Y, which entails a drop in the pressure of compression of the mixture. A further decrease in the compression pressure of the mixture during its movement in the calibrating part also occurs due to the elastic deformation of the mixture. Due to the choice of stiffness of the support rollers 7 according to the proposed ratio, the pressure at the outlet from the caliber of the pressure drops to P,

C

CR,

Max

Claims (1)

Invention Formula An installation for the continuous molding of plates, containing a mold feed feeder, a forming conveyor, a sealing conveyor located above it, and support rollers for the working arms of the conveyors forming the molding chamber with a conical pressing and calibrating parts characterized in that, in order to improve the quality of the products, the stiffness of the support rollers of the calibrating part is less than the stiffness of the support rollers of the conical pressing part of the molding chamber, and the stiffness of the support rollers is calibrated. 31-4c) S SL MOI (() with RP / iax “,, - (1 + C) - .. ii. V Max , 05-0.3 is the pressure drop ratio at the outlet of the molding chamber; maximum pressing pressure, kgf / cm; hjj - thickness of the product to be pressed, cm; 1 - the length of the gage part molding chambers, cm; V - compaction efficiency i cm / min; S to S are constant coefficients characterizing the deformation properties of the mixture.