RU1801092C - Cooling device for working members of machines for processing polymeric materials - Google Patents

Abstract

Usage: cooling the working bodies of machines for the processing of polymers in the tire and rubber industry. SUMMARY OF THE INVENTION: the device comprises circuits for controlling the temperature of the working bodies. Each circuit has a heat source and a sensor with a temperature controller that controls a three-way valve. A common circulation circuit is formed by a group of control circuits connected to pressure and discharge manifolds. They are closed between each other by a sequentially installed water-jet pump having suction nozzles for cold water and for draining the coolant from the rotor cavity, a magnetizer, a centrifugal cleaner and a discharge pump. In the temperature control circuits of the working parts, the outputs of the regulators are connected to three-line valves via a multi-pole opening contactor of the switching unit. It is controlled by the Start button of the pump and the rotor temperature controller. In the coolant temperature control loop, the controller output is connected to a three-line valve through a single-pole contactor of the switching unit. It is controlled by the Start button of the pump and the regulator of the control loop operating at maximum temperature. 4 s.p. f-ly, 4 ill. ate with

Description

The invention relates to the field of processing of polymeric materials and can be used in rubber and tire production.

The aim of the invention is to increase heat dissipation by providing accurate temperature control and eliminating water hammer at a high flow rate of the coolant.

In FIG. 1 is a schematic diagram; in FIG. 2 - centrifugal cleaner; in FIG. 3- section AA in FIG. 2; in FIG. 4 - rotor temperature sensor.

By way of example, in FIG. Figure 1 shows a diagram of a device for a worm machine consisting of six bypass control loops: a head, an extrusion zone, a plasticization zone, a loading zone, a worm (rotor), and a general circulation circuit. Each control loop has a heat source of zones 1-4 (respectively), except for the temperature control circuits of the rotor and heat carrier. Heat sources are shown in the form of inductors, which are coils dressed in sections of the housing corresponding to its functional zones. In addition to the heat source, the head, each area of the housing, including the rotor temperature control loop, have means for cooling by the circulating heat carrier. General circulation circuit and rotor circuit ISSO 0

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they do not have heat sources and at the beginning of the operation of the machine they are heated with the heat carrier heated in the head and zones of the housing. When the machine is operating, regulation in these circuits is performed by cooling. Each of the first four control loops contains a three-way diaphragm, usually open, needle valve 5, a three-way valve, usually electromagnetically closed, with a solenoid control valve b, at the outlet of which an exhaust retarder 7 is installed. the output of the three-way valve 6 is equipped with an adjustable throttle 8, which provides a smooth closing of the three-way valve. The three-way diaphragm valve 5 is controlled through a three-line valve 6 by a regulator 9, which is a control-indicating electronic device that is paired with a temperature sensor. The coolant circulating under increased pressure in the general circuit is supplied to the head and housing zones via an adjustable throttle 10 and the left shoulder of the three-way valve 5 from the pressure manifold 11 through pipelines 12 and 13, and is removed from the zones to the drain manifold 14 through pipelines 15. When stopping the flow of coolant into the zone when the right shoulder of the three-way valve is opened, the coolant is transferred via line 16 to the drain manifold 14. The most thermally stressed and requiring intensive cooling: the extrusion zone, the rotor-worm, for the purpose of using dynamic pressure, are connected by pipelines 12 and 15 to the ends of the pressure head 11 and drain manifold 14. The general circulation circuit is formed by a group of temperature control circuits for the head, rotor, extrusion zone, plasticization zone and load zone, pressure pipelines 12 of which are connected to pressure manifold 11, and drain pipelines 15 and bypass pipelines 16 to drain manifold 14. The general circuit is closed in series installed by a water-jet pump 17, the inlet of which is connected through a pipe 18 to a drain manifold; magnetizer 19; a centrifugal cleaner 20 and a discharge pump 21, the intake pipe of which is connected by a pipe 22 to the outlet of the centrifugal cleaner 20 and the pressure pipe to the inlet of the pressure manifold 11. The water jet pump 17 has suction pipes for cold water and for taking heat from the longitudinal rotor cavity. This allows the supply of cold water from a low-pressure water supply system to an increased

5 pressure, and also to eliminate the retaining pressure in the drain pipe of the rotor, which ensures reliable operation of the seal. To eliminate pressure buildup in the general circulation circuit

10 above the nominal, a safety relief valve 23 is installed, the adjustment of which is done according to the pressure gauge 24. The centrifugal cleaner device is shown in FIG. 2. The housing 25 of the cleaner 15 has a cylindrical shape. In its upper part there are windows 26 with nozzles 27 (Fig. 3) which have a tangential direction relative to the inner surface of the housing. From the outside of the housing

0 instead of windows there is a spiral distribution channel 28, the cross section of which varies depending on the flow rate of the coolant through the nozzles. From the side of the maximum cross-section, the distribution channel has a nozzle 29. The lower part of the housing 25 (Fig. 2) is closed by a sump 30, in the center of which the nozzle 31 is rigidly mounted. The upper part of this nozzle is made in the form of a funnel 32 s

0 double walls, between which guide vanes 33 are installed. The upper part 34 of the housing has a conical shape and ends with a drain pipe 35 connected to a drain line

5 36 (Fig. 1).

The rotor temperature control loop automatically maintains the preset temperature of the rotor 37. The rotor loop contains a three-way diaphragm-type valve 38, which is controlled via a three-way solenoid valve 39, which is normally closed with electromagnetic control and is coupled with a sensor 41

5 temperature through the switching unit 42. The three-way valve 39, at the outlet to the atmosphere, is equipped with a multi-chamber moderator 43, having, as in other control loops, moderators 7, various

0 by volume, divided by apertures into compartments - cameras. The first chamber is larger than the subsequent ones, which provides at the beginning a rapid pressure drop in the membrane chamber of the valve and, therefore, a quick

5, the opening of the three-way valve in terms of flow rate close to the nominal required, and then the delayed opening, providing a slow drop in the temperature of the control object. In this case, the sum of the volumes of individual cameras should not be

more than the volume of the membrane chamber of the three-way valve.

Such a change in the amount of coolant supply eliminates the influence of the inertia of the control means during cooling. In order to cool the rotor, the coolant is supplied from the pump 21 to its longitudinal cavity through an adjustable throttle 10 through the pipe 44. The coolant is returned through the pipe 45 through the water-jet pump 17 with virtually no backup pressure, which ensures the operation of the rotor seal. The temperature of the coolant is controlled using a temperature sensor 46, which is paired with a controller 47. The supply of cold water from the water supply system to the general circulation circuit is carried out through pipeline 48 through a three-way diaphragm valve 49 and a water-jet pump 17. The membrane valve 49 is controlled regulator 47 through a three-way valve 50. The compressed air required to control the diaphragm valves is supplied with the three-way valves 6, 39 and 50 through lines 51 and 52.

The switching unit 42 is designed to automatically disconnect the three-line valves 6 from the regulators 9 and the valve 39 from the regulator 40 while the rotor 37 is being heated; restoration of the control circuits of the three-way valves 5 and 38 by connecting the three-line valves J3 and 39 with the regulators 9 and 40 at a rotor temperature equal to that set on the regulator 40, working in conjunction with the sensor 41 mounted in the longitudinal plane of the rotor. At the beginning of the machine’s operation, the switching unit also shunts the output contacts of the Heat controller 47 a little according to the command of the controller 9 of the control loop operating at maximum temperature (2 output zone), and stops bypassing the contacts of the controller 47 when the set temperature in zone 2 is reached. operating at maximum temperature. To shut off the three-way valves 6 and 39, the block has an opening multi-pole contactor, with which the circuits are broken; controller 9 is a three-way valve 6 and controller 40 is a three-way valve 39. The contactor is controlled from the Start button of the pump and from the Heat contacts there is little controller 40. For bypassing the Heat contacts there is little controller 47 in the unit, a contactor controlled by the button is installed Starting the pump and heat contacts little regulator 9

loop 2 control zone operating at maximum temperature.

The rotor temperature sensor (Fig. 4) is placed in the longitudinal cavity 53 of the rotor 37.

The wire-type sensor 54 is mounted in a plastic sleeve 55 rigidly mounted on a steel sleeve 56 having, for fastening the ribs 57, with which it is welded to the tube 58 for supplying heat carrier to

0 rotor cavity to cool it. The conductors from the sensor 54 are enclosed in a metal tube 59 soldered to the tube 58. For sealing, the outlet of the sensor 54 from the plastic sleeve 55 is filled with epoxy resin 60. Heat is transferred from the rotor 37 to the sensor through a thin layer 61 of 0.1-0 , 3 mm of coolant enclosed in a chamber 62 of small volume, formed by a gap of 1-2 mm between the sleeve 55

0 and a glass 63 of metal having good thermal conductivity. The chamber 62 is made closed from direct circulation of the coolant; why seals 64 are installed in the longitudinal cavity 53. rings

5 65 and elastic element 66 replacing the spring. The compression force of the seal is controlled by a set of rings 67. The end part of the rotor is closed by a tip 68 and sealed by a rubber ring 69. In FIG. 2

0 pos. 70, electrodes are designated that serve as level sensors. The operation of the device.

Before starting, the machine is set to thermal mode. By pressing the button of the automaton5, the electric drive and the heat automation system receive power. Since the machine is cold, all temperature controllers, when energized, close the heat contacts a little. Regulators 9.

0 controlling heat sources and three-way valves 5, when these contacts are closed, they switch on induction heating coils 1-4 and supply voltage to three-line valves 6, whose electromagnetic actuators open compressed air passages from pipelines 52 to three-way membrane valves 5, as a result of which 5 are closing. Three-way diaphragm valves 38 and 49

0 by command of the regulators 40 and 47 acting through the three-line valves 39 and 50. also close.

By pressing the pump start button, the pump is turned on and voltage is applied to the open-circuit multi-pole contactor and to the single-contact contactor of the switching unit 42. The open-circuit multi-contact contactor breaks the electrical circuits from the regulators 9 and 40 to the three-line valves 6 and 39, due to

whereby the three-line valves close the air from pipelines 52 to the membrane actuators of the three-way valves 5 and 38, connecting them to the atmosphere. Under the action of the springs, the three-way valves open - the coolant begins to circulate when the heat sources are turned on through the common circulation circuit through all control and heating circuits in this case, from the heat sources of the head 1, extrusion zone 2, plasticization zone 3, loading zone 4, heating rotor 37, which does not have a heat source. When the three-way valves 5 and 38 are open, the coolant from the pump 21 is distributed through the pressure collector 11 along the control loops in which, through the adjustable throttles 10, the left shoulder of the three-way valves 5 and 38 through the pipelines 13 and 44 is directed to the heat-exchange shirts of the head 1. zones 2-4 of the casing and the longitudinal cavity of the rotor 37. From the heat exchangers, the coolant under pressure through pipelines 15 enters the drain manifold 14, from which through the pipe 18, a water-jet pump 17, a magnetizer 19 and a centrifugal cleaner 20 enters pump intake pipe 21. From the longitudinal cavity of the rotor, the coolant is returned to the general circulation circuit through pipeline 45 through the water-jet pump 17.

By pressing the pump start button, the voltage is simultaneously applied to the closing single-pole contactor of the switching unit 42, by which the heat contacts of the little regulator 47 are shunted. This eliminates the opening of the three-way valve 49 and premature cooling of the heat carrier. In practice, the optimum operating temperature of the coolant is 40–60 ° C. For heating the rotor, the temperature of the coolant is 55-70 C, therefore, if the contacts of the regulator 47 are not bridged, it will give a command to cool the coolant to the working temperature. This is also impractical because during the heating of the housing zones, the coolant cools down. When the rotor temperature rises to the set temperature, by opening the contacts of the controller 40, it stops supplying voltage to the coil of the opening multi-pole contactor, as a result of which the electrical connections are restored: the regulators 9 are three-way valves 6 and the regulator 40 is a three-line valve 39 until the end of operation cars. Since then, in the control circuits of the working bodies, the three-way valves are closed - heating continues. When the temperature in the circuit

zone 2, operating at maximum temperature, reaches a predetermined one, the regulator 9 of this zone stops supplying voltage to the coil of the closing single-pole contactor, as a result of which the contact shunting of the regulator 47 is stopped until the machine is finished working. The machine is set to thermal mode: regulators control the temperature of each in its own circuit.

During operation of the machine, due to the generation of dissipative heat, the rotor only needs to be cooled. The temperature of the wall layer of the coolant in the closed small volume chamber 62 (Fig. 4), where the rotor sensor 54 is installed, is almost equal to the temperature of the rotor 37. When the temperature of the wall coolant rises, the preset controller 40 (Fig. 1) stops supplying voltage to the three-line a valve 39, which shuts off the air supply to the diaphragm actuator of the three-way valve 38 and connects it through a moderator 43 to the atmosphere. In the enlarged moderator chamber, the pressure quickly equals the pressure of the membrane chamber of the valve 38 under the action of its spring. The valve quickly opens by an amount close to the nominal value, after which, due to the presence of throttles, air slowly leaves the membrane chamber and the needle valve also slowly changes the amount of coolant pumped through the longitudinal rotor cavity. This eliminates the possibility of thermal drift, which is manifested in the supercooling of the control object. When the set temperature is reached, the controller gives a command to close valve 38,

In the control loops, depending on the temperature change, the regulators 9 open the left shoulder of the valves 5 during cooling and the coolant is pumped through pipelines 13 through the jacket of the zones. When heated, the left shoulder of the three-way valve 5 closes, the heater is turned on, and the coolant is passed through the right shoulder of the valve 5 and pipe 16 to the common circulation circuit through the drain manifold 14.

In a general circulation circuit, the temperature is controlled by cooling the heat carrier, which is heated when heat is removed from the working parts of the machine. When its temperature rises, the controller 47 gives a command through the three-line valve 50 to the valve 49 for the inlet of cold water, which is supplied to the circuit from the water main through the water-jet pump 17. The water and heat-exchanging surfaces are cleaned using a magnetizer 19 and a centrifugal cleaner 20. Magnetized water dissolves the scale which precipitates as sludge; a centrifugal cleaner collects the sludge and discharges it from the circuit through line 36. Centrifugal cleaning is carried out by means of a pressure pump 21, which supplies the coolant through the distribution channel 28 (Figs. 2 and 3) and the nozzle 27 into the cleaner body 25. The jets directed along the tangent untwist with great speed the coolant in the body. Under the action of centrifugal forces, heavy particles are thrown to the wall of the body and settle in the settler 30; light particles, for example, in the form of sludge, oils are collected in the central part and discharged through pipe 35 into a drain line when the coolant is diluted with cold water. The cleaned coolant is sucked in from the middle part of the housing through a pipe 31 connected through a conduit 22 (Fig. 1) to a pressure pump 21, under the influence of which the coolant is continuously circulating.

The proposed device makes it possible to realize high heat dissipation by simple means, which provides a 1.5-fold increase in productivity and a decrease of 0.75% in rejects. Magnetization of the coolant and its continuous centrifugal cleaning provide high and reliable heat removal during the entire operation period and eliminate labor costs for cleaning heat-exchange surfaces.

Claims (5)

SUMMARY OF THE INVENTION 1. A device for cooling the working bodies of machines for processing polymer materials, comprising a pressure pump, a group of bypass control loops for a worm machine, each of which has a heat source and a sensor with a temperature controller that controls a three-way diaphragm diaphragm valve with electromagnetic control a valve, rotor and temperature sensors of a circulating heat carrier with regulators controlling diaphragm, three-way valves through three-line valves, characterized in that, in order to increase heat dissipation by providing accurate temperature control and eliminating hydraulic shocks at a high flow rate of the coolant, a group of bypass temperature control circuits is connected to the pressure and drain manifolds to form a common circulation circuit closed by a sequentially installed water-jet pump, having suction nozzles for cold water and for draining the coolant from the rotor cavity with a magnetizer, a centrifugal cleaner m and a discharge pump. 2. The device according to claim 1, characterized in that the outputs in the temperature control loops of the working bodies of the machine the controllers are connected to the three-line valves through a multi-pole opening contactor of the switching unit, controlled by the Start button of the pump and the rotor temperature controller, and in the circuit to control the temperature of the coolant, the output of the controller is connected to the three-line valve through a single-pole contactor of the switching unit, controlled by the Start button of the pump and the controller of the control loop operating at maximum temperature. 3. The device pop. 1, characterized in that it is equipped with a moderator of air exhaust with different volume compartments separated by diaphragms, the volume of the first of the compartments being chosen larger than the subsequent ones, and the total volume of compartments not exceeding the maximum volume of the membrane valve. . 4. The device according to claim 1, characterized in that the centrifugal cleaner is made in the form of a cylindrical body with windows tangentially located to the inner surface of the casing with nozzles, with a distribution channel of variable cross-section for uniform supply from the discharge pipe of the coolant to the nozzles, and with a vertically arranged intake a nozzle, the upper part of which is made in the form of a funnel with double walls and guide vanes mounted between them, while the upper conical part of the body is equipped with a drain branch pipe and electrodes acting as level sensors. 5. The device according to p. 1. characterized by the fact that the temperature sensor is installed in the longitudinal cavity of the rotor at a distance of 0.1 to 0.3 mm from its rotating inner surface and is rigidly fixed to the coolant supply pipe in a chamber formed between the inner wall of the cup installed in the rotor and the sleeve, closed from the direct circulation of the coolant, in which the sensor is mounted, placed in a glass with a gap of 1 to 2 mm.  & 1 I  5 5 h       .  & h