JPS6043207B2 - Temperature control device at the entrance of the regular machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature adjustment device for controlling the temperature of a steel pipe at the inlet of a forming machine in a seamless steel pipe manufacturing line to a predetermined temperature.

The regular machine process in a seamless steel pipe manufacturing line usually belongs to the final stage of hot finishing.

Therefore, the appropriateness of the temperature when passing through this process is
This greatly affects the mechanical properties and finished outer diameter of the steel pipe. However, there is no conventional means of controlling temperature in this process, and conveyor operators have to check the instructions on the steel pipe thermometer installed at the entrance of the regular machine, or visually check the degree of redness of the steel pipe itself. By doing so, the temperature at the inlet of the fixed-form machine was controlled by operating the conveyor to change the feeding speed and adjusting the holding time. Therefore, the effect on improving the quality and accuracy of the product was not so great, and the work itself was not rational or efficient. The purpose of the present invention is to provide a device that automatically adjusts the transfer speed of steel pipes in the process of transferring steel pipes from a polishing machine to a forming machine, eliminating conventional unreasonableness in this process, and improving product quality. It's about trying.

In a typical seamless steel pipe manufacturing line, a billet is heated to a predetermined temperature in a heating furnace, a hole is punched in the axial direction in the center of the pipe using a piercer roll, and then a perforated material is produced using a plug mill. It is stretched through a rolling mill and made into a raw pipe.
This process is carried out by using a polishing machine to polish the inner and outer surfaces of the raw pipe to obtain a tube with approximately a predetermined wall thickness, and at the final stage, using a shaping machine to shape the outer shape and finish it to the predetermined dimensions.
Looking at the route from the polishing machine to the standard machine in the above process, the working speed of the polishing machine is about half the efficiency of the standard machine, so two polishing lines are required for each standard machine line. Combines pipe equipment.

That is, as shown in the figure, raw tubes sent from a plug mill rolling mill (not shown) are alternately introduced into a tube polishing machine 1 by an introduction conveyor 11, and after being polished, they are placed on a tube receiving table. 1
2, the central conveyor is sent out by Kitsuka 13,
They are alternately transferred onto the table 2a and sent to the standard machine 5. The apparatus of the present invention has a conveyor table that connects a tube polishing machine and a regular forming machine as the main body of the apparatus, and the main components are such that the feeding speed of each tube can be adjusted separately. A conveyor table in a multi-stage group, a steel pipe temperature measuring device installed at necessary locations on the conveyor line, and the temperature detected by the temperature measuring device is compared with a reference temperature, and the conveyor transfer speed is determined based on the deviation. It consists of a device for adjusting the

The conveyor table is made up of a plurality of tables grouped together to form one conveyor◆ line, such as the first stage table 2a, the middle stage table 2b1, and the final stage table 2c.
Intermediate rollers 24 as idlers are installed between the tables in each stage.
are arranged.

Each table has its own drive motor 21 so that it can be operated and speed adjusted individually. A load detector 22 is attached to each of the drive motors 21 . This load detector 22 is used to prevent slip defects that occur on the tube surface due to the difference in transfer speed between the two tables when the raw tube is being transferred across the conveyor at that stage and the conveyor at the previous stage. and an electromagnetic clutch 23 provided on the roller at the starting end of the table in that stage.
1 and an electromagnetic clutch 232 provided on the roller at the end of the front stage table, simultaneously actuating these rollers to connect and disconnect them from the driving force of each motor.
That is, at the stage when the pipe is transferred from the front stage table to the rear stage table, the terminal end roller of the front stage table is in a closed state, and the starting end roller of the rear stage table is in a disengaged state and can freely rotate. When the pipe reaches a state where the pipe advances onto the latter stage conveyor and a load is applied to the drive motor 21,
The starting end roller of the rear table is set in a wet state. In the illustrated embodiment, only one conveyor table 2b in the middle group is shown, but two to three conveyor tables 2b may be provided as necessary. At the exit of the polishing machine 1 and at the predetermined positions of the first stage table and middle stage table,
Temperature detectors 31 are respectively provided to measure the surface temperature of the tube passing through that position, and the outputs of the respective thermometers 3 are individually sent to the calculation unit 41.

The output sent to the computing unit may be a value corresponding to the temperature of the intermediate portion in the longitudinal direction of the tube, or may be an average value of the portion excluding both ends of the tube. In the controller 4, the value of the reference temperature at which the tube exits the polishing machine 1 is set by a set value 44, and the corresponding output is sent to the calculator 41.
is granted to.

The calculator 41 compares the value corresponding to the reference temperature from the controller 4 with the actual measurement value input from the thermometer 3, and controls the motor 21 to slow down the reference rotational speed according to the deviation. drive Further, a temperature detector 42 is also provided at the outlet of the regular machine 5 so that the detected value can be sent to the controller 4. The operation of the apparatus of the present invention constructed as described above will be summarized as follows along with the flow of the pipe.

The red-hot raw tube sent out from the plug mill rolling machine is
It is fed into the polishing machine 1 by the introduction conveyor 11. The tube leaving the polishing machine 1 is transferred to the first stage table 2a via the tube receiving table 12, and its temperature is measured by a temperature detector 31 at the exit of the tube polishing machine. This temperature value is output from the thermometer 3 and is introduced into the computing unit 41. Here, the calculator 41 compares the value corresponding to the reference temperature introduced from the controller 4 with the actual measurement value, and adjusts the drive motor 21 of the first stage table 2a to a predetermined rotation according to the deviation. Command the speed and adjust and set the transfer speed of the first stage table. Therefore, if the temperature at the outlet of the polishing machine is higher than the reference temperature, the raw pipe is transferred on the first stage table 2a at a slower rate than the reference temperature, and if the temperature is lower than the reference temperature, it is transferred faster than the reference speed. be transported. In this way, the raw pipe transferred on the first stage table 2a is transferred to the first stage table 2a.
The temperature is further measured by another temperature detector 31 provided at the , and the actual measured value is input to another arithmetic unit 41 .

This calculator also compares the reference value and the actual measurement value, and based on the deviation, the drive motor 21 of the middle table 2b is
The rotation of is adjusted. Furthermore, the temperature of the raw tube transferred through the middle table 2b is measured in the same way, and the transfer speed of the final table is determined based on the deviation between the actual measured value and the reference value, and the raw tube is sent to the standard machine 5. . In this device,
A temperature detector 42 measures whether the tube leaving the molding machine 5 has been finished at a predetermined temperature, and an output based on the actual measurement value is inputted to the controller 4 from the thermometer 43.

The controller 4 checks whether this actual measured value is within the permissible range of the predetermined temperature, and if it deviates from the range, corrects the output to each computing unit 41 by an amount corresponding to the amount of deviation. and output it. Note that this correction only needs to be made at the start of work or for the first few steel pipe rods made on a trial basis, and there is no need for any particular correction if the manufacturing conditions are stable. The finishing temperature varies depending on the material and dimensions, but is carried out at approximately 700 to 850°C. In the above-mentioned transfer process, when the tube is caught in the molding machine 5, the final stage table 2c no longer requires a transfer operation.

For this purpose, a load cell 51 is installed on the regular machine roll to detect when the pipe is caught, and this signal is used to activate the electromagnetic clutch 52 that connects the drive motor shaft of the final stage table 2c and the conveyor roll. This makes it possible to prevent slip defects on the tube surface caused by the difference between the speed of the regular machine and the conveyor speed. According to the temperature adjustment device of the present invention, the finishing temperature of hot-finished steel pipe can be kept within a predetermined temperature range and can be made uniform, so that the uniformity of grain size can be maintained, and the mechanical properties and dimensions of the product can be maintained. Accuracy can be further improved.

[Brief explanation of the drawing]

The drawing is an explanatory diagram showing the overall configuration of the temperature adjustment device according to the present invention together with a transfer line. 1: Tube brushing machine, 11: Introducing conveyor, 12: Tube receiving table, 2a, 2b, 2c: Conveyor table, 21: Drive motor, 22: Load detector, 231, 232: Electromagnetic clutch, 24: Intermediate roller, 3: Thermometer, 31: Temperature detector, 4: Controller, 41: Arithmetic unit, 43: Thermometer, 42
: Temperature detector, 44: Setting device, 5: Standard machine, 51: Load cell, 52: Electromagnetic clutch.

Claims (1)

[Claims] 1. A pipe feeding mechanism installed between a polishing machine and a forming machine in a seamless steel pipe production line, which includes a conveyor table in a multi-stage group that can individually adjust the feeding speed of the steel pipe, and an outlet of the polishing machine. And a steel pipe temperature measurement device installed at a predetermined position on the transfer line of the conveyor table compares the set value based on a predetermined reference temperature and the actual measured value based on the detected temperature, and captures the deviation and uses it as the deviation value. A temperature adjustment device at the inlet of a regular machine, consisting of a conveyor drive motor control device provided for each conveyor table and a conveyor drive motor control device that adjusts the rotational speed of the conveyor drive motor.