01-17-2022, 07:44 AM
Wire drawing is an important industrial process. Wires are reduced in diameter through a series of die/capstan combinations which provide the desired reduction steps. Typical copper wire drawing machine within BICC Cables Ltd use up to twenty-one dies in one line and it is necessary to optimise the die drafting for each machine and final wire diameter to obtain good machine efficiency and high quality product. An important aspect in the manufacturing process is to avoid wire breakages with the resultant loss of production due to short final lengths and the associated time required to restring the drawing machine. In order to optimise the conditions for each machine and wire size, computer simulations of the process are used to predict performance by estimating factors such as the ratio of drawing stress to ultimate tensile stress, drawing force, back tension and heat generated.After having reduced the diameter as much as possible by hot rolling (smallest diameter approximately 5.5 mm), smaller diameters must be produced by cold drawing (see Golis et al., 1999; Schruff, 2004). Tension is applied to draw the hot rolled wire in several pulls down to a final required diameter between 1 and 2 mm. Calcium and sodium stearate are usually applied as a drawing lubricant. These soaps are particularly suitable at high drawing speeds because the lubricant film remains intact. Due to friction, temperatures above 150 °C and as high as 400 °C develop, which cannot be reduced by the cooling effect of the lubricant and air alone. Thus the dies are cooled with water and the wire with compressed air. Compared with earlier machines, modern dry wire drawing machines are more efficient with regard to the consumption of cooling water and lubricant as well as the filtration of stearate dust emissions. Dry aluminum wire drawing machine are machines that pull in the forward direction (Ruge and Wohlfahrt, 2001; Schimpke et al., 1977). They pull the wire as many as 14 times, i.e. a series of 14 drawing dies which are usually powered separately using rotational speed regulators. Typical technical data may be found in Table 22.4.
The control of wire temperature is very important in the fine wire drawing process. The wire speed should be increased, and the wire temperature should be dropped as much as possible. Up to now, the process design of wire drawing process depends on the experiences of experts. In this study, a wire drawing process design method was proposed to increase the productivity. The proposed method of this study includes the pass schedule and the design of a multi pass wire drawing machine. A pass schedule was performed based on the calculation of the wire temperature. Also, a new multi pass brass wire drawing machine was manufactured to apply the designed pass schedule. Through the wire drawing experiment, the effectiveness of the proposed process design method was evaluated. The final drawing speed was increased from 1,100m/min to 2,000m/min without deterioration of final drawn wire.
The double-drum wire drawing machine is the same as the pulley wire drawing machine. There are more guide wheels, especially the middle thread guide wheel between the upper and lower drums, which produces 180 when the steel wire passes through it. Because it is bent, it is not suitable for drawing large-size and high-strength steel wire; the operation of the machine is not as convenient as the pulley type, and the friction ring between the upper and lower reel and the wire wheel and other parts have a large moment of inertia, which limits the improvement of the drawing speed. This model is a transitional model developed from a pulley-type wire drawing machine to a higher-level wire drawing machine, suitable for drawing medium and small-sized steel wires.
Pulley type, double reel type and plug-in type steel wire drawing machine are all unable to draw large-sized steel wires and hard materials because of more thread guide wheels. In order to solve this problem, a straight wire drawing machine was developed. After the steel wire is wound several times on the previous reel, it directly enters the next drawing die and is wound on the next reel without passing any thread guide wheels in the middle, and the steel wire is linear between the two reels. It adopts DC drive like the looper type, and automatically adjusts the intermediate reel speed to adapt the machine extension coefficient to the actual extension coefficient of the steel wire, that is, automatically adjusts to the normal operating point of the machine. The machine compression ratio is equal to the process compression. rate.
The control of wire temperature is very important in the fine wire drawing process. The wire speed should be increased, and the wire temperature should be dropped as much as possible. Up to now, the process design of wire drawing process depends on the experiences of experts. In this study, a wire drawing process design method was proposed to increase the productivity. The proposed method of this study includes the pass schedule and the design of a multi pass wire drawing machine. A pass schedule was performed based on the calculation of the wire temperature. Also, a new multi pass brass wire drawing machine was manufactured to apply the designed pass schedule. Through the wire drawing experiment, the effectiveness of the proposed process design method was evaluated. The final drawing speed was increased from 1,100m/min to 2,000m/min without deterioration of final drawn wire.
The double-drum wire drawing machine is the same as the pulley wire drawing machine. There are more guide wheels, especially the middle thread guide wheel between the upper and lower drums, which produces 180 when the steel wire passes through it. Because it is bent, it is not suitable for drawing large-size and high-strength steel wire; the operation of the machine is not as convenient as the pulley type, and the friction ring between the upper and lower reel and the wire wheel and other parts have a large moment of inertia, which limits the improvement of the drawing speed. This model is a transitional model developed from a pulley-type wire drawing machine to a higher-level wire drawing machine, suitable for drawing medium and small-sized steel wires.
Pulley type, double reel type and plug-in type steel wire drawing machine are all unable to draw large-sized steel wires and hard materials because of more thread guide wheels. In order to solve this problem, a straight wire drawing machine was developed. After the steel wire is wound several times on the previous reel, it directly enters the next drawing die and is wound on the next reel without passing any thread guide wheels in the middle, and the steel wire is linear between the two reels. It adopts DC drive like the looper type, and automatically adjusts the intermediate reel speed to adapt the machine extension coefficient to the actual extension coefficient of the steel wire, that is, automatically adjusts to the normal operating point of the machine. The machine compression ratio is equal to the process compression. rate.