Quanzhou Ausenist Technology Co., Ltd Wire Drawing Machine Solution
The wire drawing machine is an essential piece of equipment in the production of metal wires. Its primary function is to draw various wires into the required specifications of fine wires. In recent years, frequency converters have been widely used in the wire drawing machine industry. This technology has significantly increased the automation level and processing capabilities of wire drawing machines, effectively reducing the unit energy consumption and maintenance costs of equipment, gaining widespread recognition in the industry.
I. Wire Drawing Machine Introduction
The wire drawing machine, also known as a wire puller, refers to a mechanical device that processes metal materials under pressure through stretching molds at room temperature. Through stretching, wires can be processed into various specifications of wires needed. It is a widely used mechanical device in industrial applications, extensively applied in mechanical manufacturing, metal processing, petrochemicals, plastics, wood products, wires and cables, and other industries.
II. Process Introduction
Wire Payoff: For the entire wire drawing machine process, there is no high precision requirement for the wire paying-off process. In a dual-frequency-controlled wire drawing machine, the wire paying-off mechanism automatically pays off the wire using the tension in the wire drawing section.
Wire Drawing: The wire drawing process varies significantly for different metal materials, product precision, and requirements. The wire drawing section is controlled by a main motor, and the metal wire is gradually stretched through internal pulleys to achieve the required wire specifications. During wire drawing, cooling fluid is applied to cool the molds.
Take-Up: Take-up is a critical part of the dual-frequency wire drawing machine, which has a decisive impact on the performance of the wire drawing machine and is an important criterion for testing the electrical performance of the wire drawing machine. The take-up is driven by a take-up motor to wind the wire on a take-up spool. The wire, after coming out of the wire drawing section, passes through a tension swing rod. The function of the tension swing rod is to provide real-time tension feedback to the main unit. Based on the deviation of the feedback signal, the secondary unit adjusts the output frequency to ensure constant tension during take-up.
The wire drawing section has stepless speed adjustment, large starting torque, and smooth operation.
When the take-up spool radius changes from small to large, the wire speed must remain constant.
The swing rod can be directly started at any position without manual assistance during the startup process.
The tension swing rod remains stable throughout the operation. If a change in tension is detected, the take-up should respond quickly to return to a constant tension state.
Smooth transition during start-up and shutdown is ensured, maintaining a certain tension to prevent wire breakage.
During threading, the wire drawing motor needs to jog.
In case of wire breakage, there should be a brake signal to overcome the inertia of take-up and prevent the previously wound wire from unwinding.
Regardless of whether the current take-up state is an empty spool, half spool, or full spool, it can be stopped or started at any time.
III. Dual-Frequency Wire Drawing Machine Working Principle
The main drawing frequency converter actually performs simple speed regulation but requires an output frequency change signal (i.e., analog AO output signal with AO function selected as the output frequency) as the speed reference for the take-up frequency converter. The take-up wire drawing machine calculates the synchronous output frequency based on the signal emitted by the main unit and the feedback voltage signal of the swing rod position, considering different speeds of the main unit, different diameters of the take-up spool, and different positions of the swing rod.
The payoff motor and the take-up motor are controlled by two frequency converters, respectively. The payoff frequency converter adjusts the speed through an external analog signal, and the take-up frequency converter is controlled by the frequency change output signal of the payoff frequency converter, the feedback signal of the tension swing rod, and, after analog adjustment, controls the take-up frequency converter. With changes in the diameter of the take-up spool, the feedback signal of the tension swing rod also changes. This signal and the analog AO output signal of the payoff frequency converter constitute two analog input signals. After analog auxiliary addition, the wire speed is maintained at a constant level.
Because the take-up motor operates under analog mode control, it can automatically synchronize with the main drawing, and the position of the swing rod is kept mostly in the middle position, which, to some extent, ensures constant tension during take-up.
IV. Parameter Explanation (Main Unit Part Parameters)
F0.02: 1 (External start)
F0.03: 2 (External potentiometer speed control)
F0.17: 40 (Acceleration time)
F0.18: 40 (Deceleration time)
F2.00: 1 (Forward run)
F2.01: 4 (Forward jog)
F2.02: 9 (Fault reset)
F3.03: 2 (Fault indication)
Provided solution based on the actual conditions at the customer's site:
Wire Payoff: Free wire payoff.
Wire Drawing: Choose an appropriate frequency converter based on the actual motor power. After passing through multiple stages of molds, draw the wire to the desired diameter.
Take-Up: Drive the asynchronous motor with a suitable power frequency converter. When the motor is in a stopped state, there is a brake action to prevent the take-up device from rotating.
Tension Feedback: In the middle of the wire drawing and take-up sections, there is a tension floating roller with a single-loop potentiometer at the rear end. The potentiometer feedbacks the position of the floating roller to achieve tension detection.
V. Debugging Instructions
a. Calculate the maximum operating frequency required for the main drawing frequency converter based on the maximum line speed required by the process. b. Calculate the maximum frequency required for take-up based on the actual transmission ratio. c. Set the default transmission ratio coefficient according to the mechanical rotation ratio when the spool is half full. d. Set the acceleration and deceleration time of the main drawing frequency converter as long as possible (usually 40-60s) for smooth acceleration and deceleration. e. Adjust the balance position of the tension swing rod to ensure that the mechanical midpoint corresponds to the feedback midpoint.
To facilitate wire break detection, during startup, lift the swing rod to the balance position first, wait until the wire is tensioned, and then release it to prevent the swing rod from being in the limit switch position, causing the motor not to start. During debugging, first ensure that the open-loop vector modes of the main drawing and take-up frequency converters are normal. Calculate the maximum operating frequency required for the take-up frequency converter based on the maximum line speed required by the process. Then, based on the actual transmission ratio corresponding to the maximum frequency of the main drawing, ensure that the speed difference between the front and rear stages is not significant. Adjust the take-up frequency converter based on the feedback value of the tension swing rod analog signal.
VI. Debugging Precautions
The linear relationship between the voltage feedback signal of the swing rod position and the swing rod position must be correct. If incorrect, correct it by setting an external given quantity characteristic curve.
Set a longer acceleration and deceleration time for the wire drawing motor to facilitate tracking by the take-up motor.
If the swing of the tension swing rod is too large during normal operation, check the meshing clearance between the two gears of the tension swing rod feedback signal and the swing rod.
If there is periodic sudden fluctuation during normal operation, pay attention to the position of the traversing limit switch. If it is not in the optimal position, the spool on both sides may be uneven, causing a change in the take-up diameter and affecting the smoothness of the tension swing rod.
The successful transformation of the dual-frequency wire drawing machine application solution has reduced system costs, accelerated system response times, simplified operation, and significantly improved work efficiency. The highly stable operating state has reduced the wire break rate, enhancing product quality. In practice, the transformation solution introduced in this document is a highly stable, reliable performance wire drawing machine modification solution that meets actual site requirements.