RU2232198C1 - Thermal power processing apparatus - Google Patents

Abstract

FIELD: equipment for thermal power processing of axisymmetric non-rigid shafts.

SUBSTANCE: apparatus has holding block with movable and immovable grips, furnace and power unit. Power unit has tubes telescopically connected with one another and arranged in vertical position. Tube cavities are filled with working fluid. Tube bottom parts are equipped with apertures. Movable inner tubes are provided with return valves for opening of apertures on backward motion of inner tubes in downward direction. Bulk material is used as working fluid.

EFFECT: enhanced reliability in operation and increased efficiency in thermal power processing of objects.

2 cl, 2 dwg

Description

The invention relates to the field of thermal power treatment (TCO) of low-rigidity axisymmetric parts of the “shaft” type and can be used at engineering enterprises.

A device for TCO shafts of low rigidity, including a slipway with grips in end sections, and the slipway is made in the form of a pipe made of metal with a coefficient of thermal expansion less than that of the product [1].

The disadvantage of this device is the inability to ensure the stability of the applied force during the TCO process, which can lead to material reinforcement, uneven metal structure along the shaft length, permanent deformation and, consequently, dimensional instability during the operational period with loss of accuracy.

The closest device of the same purpose to the claimed invention, selected as a prototype, is a device for TCO, including a slipway with movable and fixed grippers, a shaft furnace, a power unit [2].

The disadvantage of this device is the design complexity due to the use of a power unit in the form of hydraulic cylinders, the low reliability of the device due to the action of high temperatures near the hydraulic part of the device, which leads to the possibility of leakage of the working environment, high fire hazard, as well as the difficulty of regulating workloads due to high temperature deformations of the working elements of hydraulic cylinders.

The problem to which the invention is directed is to increase the reliability and efficiency of TCO with the following technical results: simplifying the design of the device for TCO by using its internal resources; increasing the stability of the material structure and residual stresses along the length of the part by controlling the magnitude of the force applied during TCO.

This problem is solved by the fact that in the device for TCO axisymmetric non-rigid shafts containing the slipway with movable and fixed grippers, the furnace, the power unit, the latter is made in the form of vertically placed telescopically interconnected pipes, the cavities of which are filled with a working medium, and the bottom parts of which are made with holes, while the inner pipes are movable and equipped with check valves to open the holes when the tubes extend upward, the outer pipes are fixed and equipped with exhaust valves for opening holes during the reverse movement of the inner pipes down, and bulk material is used as a working medium; exhaust valves can be made with the possibility of regulating the force of their compression against the holes in the bottom of the pipes.

The implementation of the power unit in the form of telescopically interconnected pipes allows you to adjust the length of the working area of the device, which allows you to process parts of different lengths, and also adapt to temperature deformations of the part during the TSS, reduces the energy consumption of the TSS process due to the fact that only the workpiece is heated, and the entire stock for the implementation of TCO.

The vertical arrangement of the pipes allows the use of gravitational forces to control their outflow by pouring the working medium.

The implementation of pipes with internal cavities allows you to make the device for TCO more compact due to the use of them as guides for movable gripping, as well as to accommodate the loading mechanism.

Filling the internal cavity of the pipes with a working mixture increases the reliability of the device due to greater stability under compressive forces under TCO, it does not require complex control equipment, operating conditions are simplified due to the fact that the flow rate of bulk material does not depend on pressure, but on the size of the outlet .

The implementation of the inner pipes with the bottom allows you to combine the functions of power loading and the direction of movement of the movable grip, and the execution of the outer pipes with the bottom forms a cavity under them for the working mixture.

Installation in the bottom parts of the valve pipes makes it possible to combine the supporting structure of the device for TCO with the device for controlling the power load of the shaft during processing.

The installation of check valves in the openings of the bottom of the inner pipes, which are designed to open the holes when the pipes extend, allows the adjustment of the position of the movable gripper in the adaptive mode without additional adjustment during thermal deformation of the workpiece, while the thermal elongation of the workpiece is monitored.

The execution of external pipes movable allows you to track the thermal deformation of the workpiece.

The execution of the inner tubes motionless makes it possible to retract the inner tubes by pouring the working mixture into the cavity under the inner tubes.

The location in the bottom of the outer pipes of the exhaust valves allows you to create and control the force loading of the product when it is cooled by compensating for temperature deformations during cooling of the workpiece and creating a force circuit with the formation of plastically deformed directed structures in the workpiece.

The use of a granular mixture as a working medium makes it possible to adaptively adapt the extension of pipes with a given force without complex control systems.

The execution of valves with a force control of their preload allows you to pre-set the required applied tensile force at TCO taking into account the processing conditions (dimensions of the part and its material).

A general view of the device is shown in figure 1, a variant of the control system is shown in figure 2.

The device (Fig. 1) contains a slipway 1 on which a fixed grip 2 and a power unit 3 are attached in the form of external 4 and internal 5 pipes with a bottom part 6 with an opening 7 and a check valve 8. The cavities 9 of the external 4 and internal 5 pipes are filled with loose a mixture of 10 (sand, graphite, cast iron). The furnace 11 and the movable gripper 12 are arranged concentrically to the axis. In the bottom of the outer pipes 4 there are openings 13 with adjustable exhaust valves 14 connected to a control unit (not shown).

This block may comprise (FIG. 2) a measuring device 16, which is connected to an amplifier 17, a comparing device 18, an actuator 19 for adjusting the clearance of the exhaust valve 14. A setting unit 20 of the applied force is also connected to the comparing device.

The device operates as follows.

The shaft 15 is placed in the furnace 11, clamped in the movable 12 and stationary 2 captures and conduct its heating, in which due to the thermal extension of the shaft 15, the movable gripper 12 is moved with the extension of the inner tubes 5 of the power unit 3. This opens the check valve 8, and through the hole 7, the bulk mixture 10 is poured from the inner 5 into the outer pipe 4, filling the cavity 9 under the closed bottom 6. When the shaft 15 is cooled, it is thermally compressed, and due to the grippers 2 and 12 it is stretched when cooled and securing the shaft in a straight condition, which leads to the formation of stable equilibrium structure due to plastic deformation.

Using the control unit, the device will work as follows. To create a constant tensile force, the adjuster 20 of the magnitude of the applied force is pre-adjusted. When the load changes in the TCO process, its value from the measuring device 16 of the strain force is supplied through the amplifier 17 to the comparing device 18. The error signal from the measuring device 16 and the setter 20 is fed to the valve 19 for adjusting the clearance of the outlet valve 15, which, by changing the size of the hole 14, controls the flow rate of the bulk material 11, due to which the magnitude of the applied force is stabilized or changed according to a certain law.

The treatment cycle is repeated until the inner cavity is completely empty, after which the granular mixture from the fixed part of the slipway is poured back into the cavities of the movable pipes.

Using this device allows you to increase the reliability of the TSS, to increase the stability of the material structure and residual stresses along the length of the part, to simplify the design of the device for TSS.

Literature

1. A.S. USSR No. 1407696, cl. C 21 D 1/62, 1/63, 1988.

2. Drachev O.I. An experimental setup for thermomechanical processing of parts. // Technology and automation of mechanical engineering. Issue 47. - Kiev: Technics. - 1991. - S. 40-44.

Claims (2)

1. A device for thermoset processing axisymmetric non-rigid shafts, comprising a slipway with movable and fixed grippers, a furnace, a power unit, characterized in that the power unit is made in the form of vertically placed, telescopically connected pipes, the cavities of which are filled with a working medium, and the bottom parts which are made with holes, while the inner pipes are movable and equipped with check valves to open the holes when the tubes extend upward, the outer pipes are fixed and provided with exhaust valves for opening holes during the reverse movement of the inner pipes down, and bulk material is used as the working medium. 2. The device according to claim 1, characterized in that the exhaust valves are made with the possibility of regulating the force of their pressing against the holes in the bottom of the pipes.

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