The quality of wire production is a very concerned problem of cable manufacturers, because the quality and efficiency of wire drawing directly affect the production process of the next process, and play a decisive role in the quality of cable. The following problems often appear in the production of wire drawing machine.
Precise control of the outer diameter deviation of products
Due to the continuous production of metal wire equipment, the speed of wire drawing will gradually be out of sync with that of annealing. During wire drawing, due to the fast and slow traction speed, large and small irregular segments appear in the wire diameter. The reasons for this phenomenon are as follows:
1. The tension on the wire storage wheel is not stable, and there may be many places where the air pressure is used in the production workshop, which will cause the air pressure of the air pump of the wire drawing machine to be large or small, which will also cause the tension of the wire storage device to be unsteady. Because the speed of wire take-up is constant, the tension on the wire drawing is not constant, which can cause the deviation of the outer diameter of the single wire to be unable to be accurately controlled.
2. The jitter of the wire on the annealing wheel makes the wire annealed when it is loose or tight. The current density of annealed wire is large or small, while the strength of the wire at a higher speed is relatively low, so it is easy to cause the copper wire to ignite on the annealing wheel, making the wire surface uneven due to the effect of sparks.
3. The wear caused by the long-term use of the gearbox of the main motor can make the speed of the constant speed wheel of the drawing not match with the traction speed and the take-up speed, thus forming the drawing of the single wire.
Solution: lubricate the wire accumulator well to avoid the reverse friction force on the wire during high-speed operation, and then fine the wire; adjust the tension of the wire to make the stroke of the wire always close to the annealing wheel; ensure the steel ring of the annealing wheel is in good condition and avoid the unstable annealing current due to the surface defect of the steel ring.
According to the actual situation of the wire drawing machine, re mold the wire drawing machine: adjust according to the wire drawing principle, so that the speed of annealing wheel / speed of constant speed wheel = forward slip coefficient × diameter of constant speed wheel / diameter of annealing wheel, in which the diameter of constant speed wheel and annealing wheel are known, and the speed of constant speed wheel and annealing wheel can also be measured, From this, the forward slip coefficient can be obtained. By the slip coefficient, the die of this drawing machine can be rearranged, so that the die can meet the requirements.
The reason of oxidation on the surface of drawing single wire
1. The temperature of the cooling water in the sealed chamber is too high, which exceeds 40 ℃, so that the sealed chamber can not achieve the required cooling effect on the single wire, resulting in the temperature of the single wire is still very high after annealing, and the single wire is oxidized when encountering oxygen in the air at high temperature.
2. If the saponification liquid content of the cooling liquid in the sealing chamber is not enough, the friction force between the monofilament and each guide wheel will increase, and then the temperature of the monofilament will rise again, resulting in the surface oxidation of the monofilament.
3. The water pressure and quantity of cooling water in the sealing chamber are not enough, so that the single wire can not achieve satisfactory cooling effect.
Solution: regularly check whether the equipment for cooling circulating water operates normally and whether the cooling effect is normal; add substances that can improve the concentration of saponification liquid in the sealing chamber at regular intervals, so as to change the content of saponification liquid in the cooling water and ensure the normal operation of the monofilament on the guide wheel; regularly check whether the water pressure of circulating water is normal and constantly according to the water during production Pressure changes to change the pressure and quantity of cooling water entering the seal chamber.
Causes of frequent broken wires in wire drawing production
1. The sizing area of the drawing die will be enlarged due to the normal wear during the continuous production of the drawing die.
2. In the process of production, the quality defects of all kinds of rods appear irregularly, which makes the monofilament broken by various unpredictable tension during drawing deformation. This situation seldom occurs when the bar material is good.
3. In production, the annealing current is not constant, the current is suddenly high, and the single wire is broken or fused by sudden strong current during annealing.
Solution: before production, the metal rod to be produced shall be fully self inspected, and the quality defects of the metal rod shall be found in time, and corresponding countermeasures shall be found in time according to different situations, or the wire drawing speed shall be reduced, or the defective section shall be removed. During production, it is necessary to observe whether the annealing current of drawing is normal, especially when it is just started, pay special attention to the change of annealing current, adjust the size of annealing current according to the change of wire speed, and then make the annealing current gradually increase with the increase of wire speed, so as to ensure the normal operation of the equipment.
It is believed that as long as the above points are controlled in the actual production, the quality and production efficiency of metal drawing products will be improved to varying degrees, so as to provide a strong production guarantee for the next process production better and faster.