SU1135650A1 - Apparatus for making multiple-layer asbestos cement products - Google Patents

Abstract

DEVICE FOR MANUFACTURING MNOGOSLOYN1H asbestos cement products containing bath mesh cylinders endless working cloth with the drive shaft, sizing drum and mounted above the cloth feed bin dry mixture with a feeder, characterized in that in order to provide stacking of Schirin cloth uniformly over the thickness of the cement layer, it is equipped with a cement paver in the form of a vibrating track that is hinged to the flow-hopper with a bevel at the end and a layer thickness regulator control panel mounted above it, with the bottoms The vibrating channel on the section from the bunker to the lower end of the plate is made with a longitudinal groove with a bevel of each reef in the direction of the smooth discharge end of the vibrating channel. Fzg.i

Description

The invention relates to the building materials industry and can be used for the manufacture of asbestos-cement products, in particular for applying a layer of dry cement to asbestos-cement film on an endless working cloth of a sheet-forming or pipe-forming machine.

A device for the manufacture of asbestos-cement products, a bath of mesh cylinders, an infinite working cloth, and format and anchor drums 1 are known.

The disadvantages of this device is a significant amount of waste cement and asbestos, as well as the incomplete use of the strength properties of raw materials, which leads to a decrease in the quality of products.

Closest to the proposed device for the manufacture of multilayer asbestos cement products, a bath of mesh cylinders, an infinite working cloth with a tension shaft, a format drum and a dry asbestos cement mix under a working cloth and a calibrator 2.

However, the known device does not provide for laying a thin, uniform in height and width of the cement layer on the working felt of the molding machine, which leads to the formation of voids between the layers and the stratification of the finished multilayer products.

The purpose of the invention is to ensure that the width of the cloth is laid across a uniform layer of cement.

This goal is achieved by the fact that the device for the manufacture of multilayer asbestos cement products, a bath of mesh cylinders, an endless working cloth with a leading shaft, a format drum and a dry mix with a feeder mounted above the cloth, is equipped with a cement stacker pivotally attached to the expendable vibrolot bunker a bevel at the end and a plate-regulator of the layer thickness that is cantilevered over it, the bottom of the vibrating channel from the bunker to the lower end of the plate made with nym grooving beveled each riff towards the smooth discharge end of the vibrating chute.

FIG. 1 shows schematically the proposed device, a general view; in fig. 2- cement stacker with a layer thickness regulator; in fig. 3 - vibrating channel, plan.

The device contains a bath of mesh cylinders 1, an endless working cloth 2 with a leading (supporting) shaft 3 and a press 4 and a format drum 5. Above the working cloth 2 a feed bin 6 is divided by a partition into two compartments for various types of cement, each of which is equipped with a paddle feeder 7

The exit slots of the compartments of the hopper 6 are width calibrated, the width of the slot being regulated by a valve (not shown). Under the bunker 6, a cement handler is installed in the form of a vibrating trough 8 sharnrna attached to the bunker with a vibration exciter 9 and a plate-regulator 10 mounted above it.

Vibrating channel 8 is made of stainless steel with a polished surface. The width of the vibrating channel is equal to the width of the asbestos-cement film on the working cloth. Vibrating channel 8 has limiters on the sides (not shown) that do not allow the cement to flow when sideways vibrate. The bottom of the vibrating channel 8 in the area from the bunker 6 to the lower end of the plate 10 has a corrugated surface with longitudinal reefs 11, each of which has a bevel towards the smooth discharge end of the vibrating channel 8, also made with a bevel.

The device works as follows. Cement of the required types and grades is supplied to the compartments of the feed bin by 6 conveyors. Inclined dampers are installed on the front walls of the compartments, which regulate the gap width through which the cement passes from the bunker to the feeder. By rotating the shafts with blades, the cement from the feeder 7 is fed to the vibratory channel 8 of the cement stacker. The sequence of cement supply and 5 compartments to the cement stacker is controlled by a switch.

Due to the hinge adjusts the height of the end of the vibrating channel 8 above the endless working felt 2. When the tilt angle of the stacker, frequency and amplitude of vibrations of the vibration exciter 9 and the vibration angle change, the feed rate of the cement layer changes. The capacity of the stacker increases with an increase in the angle of inclination within 0, 8, and 12 ° while simultaneously increasing the supply of cement from the compartments of the feed bin. A change in the angle of vibration is provided by a tandem suspension (mounting) of the vibration exciter. By changing the angle of inclination of the plate-regulator 10 and, accordingly, changing the width of the slit through which the cement passes, as well as the time of vibration when the cement layer passes from the regulator to the end of the vibrating channel, the thickness of the cement layer 12 laid on the layer of asbestos with cement particles applied mesh cylinders 1 on an endless working cloth 2. The end of the vibrating channel has a bevel for smoother laying of a layer of cement on a layer of asbestos fibers with cement particles on an endless working felt. Longitudinal grooves in the bottom of the vibro5 tray provide a uniform supply of cement across the entire width of the stacker. The height of the ribs of the tray is reduced at a smooth, flat area to ensure uniform flow of cement across the width of the tray before the layer thickness adjuster. When the stacker angle decreases to vibration patterns at the end of a smooth, flat section, it decreases with a simultaneous decrease in the laying speed of the cement layer on the endless working felt. In this case, a layer of cement of the greatest thickness is obtained, approaching in its value to the width of the gap between the regulator 10 and the vibrating tray 8. Thus, the inclination of the vibrating tray 8 determines the time of vibration when the cement layer passes from the end of the regulator to the end of the stacker with a corresponding decrease in the layer thickness cement due to its compaction and spreading during vibration on the smooth, flat end of the stacker. The amount of slope is established depending on the required thickness of the cement layer and its workability, determined by its humidity, temperature and fineness of the cement. A monolayer (finely ground cement) requires a lower frequency and amplitude of vibrations than coarse-grained cement, and it becomes fluid when vibrated in less time. On the polished flat surface of the stacker, fine ground cement flows from the end of the regulator to the end of the stacker in an even layer without any hillocks. When using an electromagnetic vibrator and the length of the vibrating channel 1.0–2.5 m, an industrial current with a frequency of 50 Hz is converted into a non-industrial current with a frequency of 25 Hz or 1500 cal / min by thyristor frequency converters. When the current is changed from the control panel of the molding machine, the oscillation amplitude smoothly varies within ~ -2 mm. For a uniform flow of cement over time and to avoid the formation of backwater of cement in front of the regulator, the smooth discharge end of the vibrating channel has a downward angle of about 12 ° greater than the section of the vibrating channel from the cement hopper to the end of the longitudinal corrugations. The downward slope of the smooth discharge end of the vibrating channel does not exceed 16 °. In addition to the uniform distribution of cement across the width of the vibrating channel, longitudinal grooves provide vibro-liquefaction of cement monolayers and contribute to their more uniform movement along the vibrating channel. A dry layer of cement, along with a wet layer of asbestos fibers with cement particles, is fed to the format drum 5 and under a pressure of 25 kg per meter p. cm length of the press shaft 4 and further under the pressure of 50 kg per 1 pog. cm. The lengths of the lead (support) ral 3 are sealed to a monolithic tape, corresponding to the width and dimensions of the asbestos-cement product. In the loose state, the thickness of the cement layer is 0.4-2 mm, and after compaction the cement layer in the product decreases to 0.2-1.0 mm. The primary layer of cement applied from the endless working felt to the format drum is the inner protective layer of the asbestos-cement pipe or the outer facing layer of the asbestos-cement sheet. The outer layer of the asbestos cement sheet is subjected to force rolling under the pressure of the press shaft and the drive (support) shaft b-10 times equal to the number of layers in the sheet, the innermost protective layer of the asbestos-cement pipe is most compacted. The wetting of the dry cement layer of the molded product is due to the moisture from the fluffed asbestos fibers and the moisture of the endless working felt. When moistened, the particles of finely ground cement enter into a plastic state of fluidity and fill all the pores of the asbestos fibers under pressure. Regulation of the amount of water in the working cloth is carried out by pressure of the pressure roller on the mesh cylinder and the vacuum box in front of the format drum, as in the usual “wet” technology for the production of asbestos-cement products using the Gatchchek method. In order to reduce the entrainment of fine cement particles with wastewater during filtration, eliminate premature hydrotation and seizure, as well as improve product quality, Portland cement from the receiving hopper is fed to an eccentric screen, where it is dispersed into three fractions: major inclusions falling into the cement; portland cement with a specific surface area of 2200-3100 for the additive (within 1-30% of the consumption norms of the usual Gatchek method) to the asbestos suspension entering the baths of mesh cylinders, and fine-ground cement with a specific surface 3100-3800 (the stacker is applied to the wet a layer of asbestos fibers with cement particles on the endless working cloth of the molding machine). Without interrupting the technological cycle, both asbestos cement sheets of normal gray color and sheets lined with a layer of colored cement are manufactured on the same installation. At the plant, a qualitatively new material is obtained, in which the advantages of multilayer and monolithic material in one product are combined. As the hydrotation of fine ground high-strength cement flows in the molded product, the density and strength of the product increase due to the germination of cement grains between the asbestos fibers, and the porosity and their water absorption decreases accordingly.

The elimination of defects in the durability of products and their delamination during repeated freezing and thawing is eliminated due to the full use of the cement in the retaining properties and a change in the structure of the primary layers.

The proposed installation with a cement handler with a vibrating device and a regulator is hermetic and does not create cement dust in the workshop. The section from the end of the regulator to the end of the stacker is also covered with a metal casing, which is hinged above the stacker with an exit slot between them. Cement does not accumulate against the walls of the stacker, but completely vibrates all the space in front of the regulator during vibration.

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Claims (1)

DEVICE FOR MANUFACTURE OF MULTI-LAYER ASBESTOS-CEMENT PRODUCTS, containing bathtubs for mesh cylinders, an endless working cloth with a drive shaft, a formatted drum and a dry mix supply hopper with a feeder mounted above the cloth, characterized in that, in order to ensure that the cloth is evenly spread across the width of the layer cement, it is equipped with a cement stacker in the form of a vibratory tray with a bevel at the end and a plate-adjuster of the layer thickness cantilever mounted above it and hingedly attached to the expendable hopper; otka the area from the hopper to the lower end of the plate ¹ vypol Neno with longitudinal grooving bevel each reef towards the discharge end of the vibrating chute smooth.