RU2503506C2 - System of automatic control over application of insulating coat on cylindrical article inner surface - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to application of coats on inner surfaces of various cylindrical hardware. Proposed system comprises level transducer electrically connected with microprocessor device of control and processing, electromechanical drive mechanically engaged with drain shutter, pump unit with electrical output connected with control unit first output, said control unit being communicated via shutoff valve with manifold communicating the article with said drain shutter. Crossing adapter is installed in the system between level transducer and article top edge and hydraulically connected with reactor first inlet. Reactor second inlet is communicated with pump unit hydraulic inlet. Reactor outlet is connected with pump hydraulic inlet while control unit second output is connected with shutoff valve electric input.

EFFECT: higher quality of coating.

1 dwg

Description

The invention relates to devices for coating the inner surface of cylindrical products and can be used when applying protective coatings to the inner surface of various types of cylindrical products, including pipes, which require a high degree of uniformity of the thickness of the coating material over the entire length of the product, accuracy at consumption of applied material, as well as automation of the process of filling and draining.

Known devices in which the coating is carried out by spraying from a moving nozzle in the cavity of a cylindrical product with subsequent drying and annealing of enamel in inductors or slot furnaces (analogues RU 23050l C2 B05C 7/08, B05D 7/22 from 07.11.2005; RU 2315668 C1 B05C 7/08 dated 06/05/2006; RU 2338603 C1 B05C 7/08 dated 05/08/2007; RU 2340408 C2 B05C 7/08, B05C 7/08 dated 10/17/2006; RU 2311966 C1 B05C 7/08 of 06/05/2006; RU 96793 B05C 7/08 of 08/20/2010).

The disadvantages of analogues include the uneven spraying of the coating material with the help of nozzles, their fast clogging in the case of using viscous liquids, as well as the unevenness associated with the separation of the applied material when filling the product and material overflow associated with incorrect control of the filling rate of the cavity of the product.

The prototype is a device (RU 106850 U1 B05C 7/08 from 07/27/2011), which contains a collector, a pump unit control unit, a pump unit, a shut-off valve, a drain valve, a level sensor, a microprocessor processing and control device, an electromechanical drive. Coating is carried out by controlled filling of the inner cavity of the product with a cylindrical shape by the applied material, followed by controlled discharge of its excess, drying and annealing.

The disadvantage of the prototype is that the device does not provide the necessary uniformity of the coating at the ends of the products. This is due to the fact that the insulating material is a colloidal mixture of particles (suspension), which are deposited during pouring into a vertically standing product, creating a non-uniform density of the material being drained. In the upper part of the product, the density of the suspension is less than in the lower. Stratification of the material occurs along the height of the product. This leads to uneven coverage even at a stable drain rate.

The task is: to eliminate the unevenness of the coating along the length of the product associated with the heterogeneity of the suspension resulting from pouring.

The solution to this problem is achieved by the fact that in the automatic control system for applying an insulating coating to the inner surface of cylindrical products containing a level sensor electrically connected to a microprocessor-based processing and control device, an electromechanical drive mechanically connected to a drain valve, a pump unit whose electrical input is connected with the first output of the control unit, docked through a shut-off valve with a manifold hydraulically connecting the product with a drain valve, according to the invention, an adapter is additionally installed between the level sensor and the upper cut of the product, hydraulically connected to the first input of the reactor, the second input of which is hydraulically connected to the drain valve, the output of the reactor is connected to the hydraulic input of the pump unit, and the second output of the pump control unit the unit is connected to the electrical input of the shut-off valve.

The system carries out the controlled filling of the internal cavity of the product with the coating material in an upright position with its subsequent entry into the adapter nozzle and discharge back into the reactor. Reaching the upper cut of the product, the coating material enters the transition nozzle, from which it is drained back into the reactor through the hydraulic channel, thereby continuously circulating the suspension, which ensures uniform distribution of the density of the coating material over the entire height of the product. According to the signal from the control sensor of the pumping unit, at a time instant empirically found for different materials and pipe sizes, the circulation stops, the shut-off valve closes. After that, at a signal from the control unit of the pumping unit, the filling speed of the product decreases and its supply to the collector automatically stops, by shutting off the shut-off valve, and controlled material flowing through the drain valve begins. This allows you to ensure uniform coverage at the edges and along the entire length of the product.

The invention is illustrated by figure 1.

The article 4 to be coated is mounted vertically on the manifold 6, to which a pumping unit 10 is connected through a shut-off valve 9, into which the applied material is supplied from the reactor 12, designed to store and maintain a constant temperature and consistency of the suspension. A transition nozzle 2 is connected to the upper edge of the product, connected to the reactor 12 by means of a hydraulic channel 5. The transition nozzle 2 is made in such a way that a level 1 sensor is mounted above it, connected to the input of the microprocessor processing and control device 3, the first output of which is connected to the input of the control unit of the pumping unit 11, connected by one output to the electrical input of the pumping unit 10, and by a second output to the electrical input of the shut-off valve 9. The second output of the microprocessor device Three processing and control 3 is connected to the input of the electromechanical actuator 7, mechanically connected to the drain valve 8.

The operation of the device involves two stages. At the first stage, the applied material is pumped into the product through the shut-off valve 9 using the pump unit 10 from the reactor 12. After filling the product, the material enters the adapter nozzle 2, connected via the hydraulic channel 5 to the reactor 12. The current value is measured using the level sensor 1 the height of the liquid column in the cavity of the product. Data from the level sensor 1 is fed to a microprocessor-based processing and control device 3, from which a signal is sent to the control unit of the pump unit 11. The control unit sends signals to the pump unit to slow down the filling rate of the internal cavity of the product when approaching the upper cut. A transitional nozzle 2 is installed on the upper section of the product, which is connected to the reactor 12 using a hydraulic channel, thereby continuously circulating the applied material, aimed at uniform distribution of the density of the applied material over the entire height of the product. Subsequently, the performance of the pumping unit is maintained in such a way that the filling speed is equal to the discharge speed. After that, under the influence of a control signal from the control unit of the pump unit 11, the pump unit stops and the shut-off valve 9 is closed. At the second stage, a controlled discharge of material is carried out. On command from the microprocessor processing and control device 3, a signal is supplied to the electromechanical actuator 7 and the valve 8 is gradually opened, through which excess material is applied at a constant speed. Due to the viscosity of the material, it sticks to the inner walls of the product. The thickness of the coating depends on the viscosity and speed of the material. The resulting film is an insulating coating. The invention allows you to evenly distribute the material along the entire length of the product, which increases the quality of the coating.

In addition to ensuring uniformity along the entire length of the product, the development allows you to fully automate the coating process. This installation allows you to increase productivity and work culture and automate production.

If necessary, the speed of filling the cavity of the product with the coating material and its discharge can be controlled according to a given program, thereby optimizing the time of the technological process.

Claims (1)

The automatic control system for applying an insulating coating to the inner surface of cylindrical products, containing a level sensor electrically connected to a microprocessor-based processing and control device, an electromechanical drive mechanically connected to a drain valve, a pump unit whose electrical input is connected to the first output of the control unit, docked through shut-off valve with a manifold hydraulically connecting the product with a drain valve, characterized in that in the system between the level sensor and the upper section of the product an additional adapter is installed, hydraulically connected to the first inlet of the reactor, the second inlet of which is hydraulically connected to the drain valve, the outlet of the reactor is connected to the hydraulic inlet of the pump unit, and the second output of the control unit of the pump unit is connected to the electrical input of the cut-off valve.

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