Patent Application
20200181747
The present disclosure relates to a continuous wire drawing method, and in particular, to a continuous wire drawing apparatus, to heat a metal wire material continuously at a heating temperature in a heating area.
No matter whether a conventional wire drawing device uses scroll wheels or tower wheels to transport a wire material, a similarity lies in: When the scroll wheels or the tower wheels rotate to transport the wire material, the wire material penetrates a wire drawing die disposed between a scroll wheel and a scroll wheel or between a tower wheel and a tower wheel, and a wire diameter of the wire material is decreased by using a convergent structure of a pore diameter of the wire drawing die. Although this wire drawing manner helps to automatically produce a lot of wire materials having a same wire diameter specification, a known cold drawing process has an area reduction of 10%. If a wire diameter of a brass wire material is drawn from 01.2 mm to 00.5 mm, about 20 die times (the die times refer to a quantity of times of forming processes using wire drawing die) are needed, and 6 times or more of annealing and softening processes are further needed. Therefore, relatively high process costs and time are needed to make the wire diameter of the brass wire material reach a target wire diameter.
Taiwan patent (Publication NO. 201021932A) discloses a wire drawing method to provides a to-be-drawn wire material. The wire material is wound on two corresponding once wire drawing wheels and penetrates a wire drawing die disposed between the once wire drawing wheels, next the once wire drawing wheels are scrolled to make the wire material penetrate the wire drawing die to perform once drawing to decrease a wire diameter of the wire material, then the wire material finishing once drawing is wound on two corresponding twice wire drawing wheels, and the twice wire drawing wheels are scrolled at different rotational speeds to generate a pull to the wire material, to perform twice drawing on the wire material and decrease the wire diameter of the wire material again to finish the wire drawing process. In the foregoing patent document, the rotational speed of the twice wire drawing wheels may be adjusted and set based on a required size of the wire diameter, to generate different drawing forces, thereby achieving effects of simplifying production steps, reducing production costs, and improving production efficiency. However, in the foregoing patent document, a wire drawing die is still needed in a forming process to decrease the wire diameter of the wire material, and heating processing is also needed.
Therefore, a continuous wire drawing apparatus and method need to be provided to resolve the foregoing problem.
The objective of the present disclosure is to provide a continuous wire drawing apparatus and method, to heat a metal wire material continuously at a heating temperature in a heating area.
To achieve the foregoing objective, the present disclosure discloses a continuous wire drawing apparatus, including: a wire releasing scrollbar and a wire collecting scrollbar, being respectively a wire releasing end and a wire collecting end of a metal wire material; a wire drawing force control unit and a back force control unit, providing a drawing force to the wire collecting end and providing a back force to the wire releasing end respectively, so that the metal wire material moves towards the wire collecting scrollbar; a heating unit, disposed between the wire releasing end and the wire collecting end, and adapted to heat the metal wire material continuously at a heating temperature in a heating area, wherein a range of the heating temperature is 50° C. to 300° C. above a recrystallization temperature of the metal wire material, whereby the metal wire material is deformed by and with a strength difference between the drawing force and the back force; and a cooling unit, disposed between the heating unit and the wire collecting end, and adapted to cool the metal wire material continuously at a cooling temperature in a cooling area.
The present disclosure further discloses a continuous wire drawing method, comprising the following steps: providing a metal wire material, comprising a wire releasing end and a wire collecting end; providing a drawing force to the wire collecting end, and providing a back force to the wire releasing end, so that the metal wire moves; heating the metal wire material continuously at a heating temperature in a heating area, wherein a range of the heating temperature is 50° C. to 300° C. above a recrystallization temperature of the metal wire material, whereby the metal wire material is deformed by a strength difference between the drawing force and the back force; and cooling the metal wire material continuously at a cooling temperature in a cooling area.
According to the continuous wire drawing apparatus and method of the present disclosure, first, no wire drawing die is needed in a forming process, and die cost can be reduced. Second, no annealing process needs to be performed on a metal wire material after a continuous drawing process, and unnecessary energy consumption can be reduced. Third, the metal wire material is protected by a gas in the thermal forming process, and cannot be oxidized in the thermal forming process. Fourth, a wire drawing process of the present disclosure that improves a design limitation of an area reduction of a conventional wire drawing die, and is applicable to a wire material difficult to form can significantly reduce production cost and promote industrial competitiveness.
To make the foregoing objective, features, and characteristics of the present disclosure more obvious and understandable, related embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.
In this embodiment, using a brass wire material as an example, a metal wire material of 08 mm to 04 mm is manufactured first by vacuum continuous casting. (1) The metal wire material 2 is wound on the entire continuous wire drawing apparatus 1, including the wire releasing scrollbar 12 (that is, the wire releasing end 21), the heating unit 13, the cooling unit 15, and the wire collecting scrollbar 16 (that is, the wire collecting end 22), and the back force control unit 11 and the wire drawing force control unit 17 set a back force to 10 N to 600 N, and a drawing force (that is, a wire drawing force) to 100 N to 6000 N. (2) The heating unit 13 includes a cavity 132 and a heating element 131, the heating element 131 can be a closed heater or an inductive heating coil, an effective interval of the heating area H is 10 cm to 50 cm, a heating temperature is adjusted to be in a range of 500° C. to 800° C. in accordance with the size of the metal wire material 2, a protective gas such as nitrogen is added during heating and forming process, to maintain a positive pressure in the cavity 132 (such as a glass shield) of the heating unit 13, and a wire collecting speed is set to 2 m/min to 30 m/min. (3) The formed metal wire material 2 penetrates the cooling unit 15, and a cooling temperature of a cooling fluid 151 is maintained at 25° C. to 30° C. by using the cooling unit 15 such as a chiller. In another embodiment, for the formed metal wire material 2, an air cooling manner can also be used to maintain the cooling temperature at 25° C. to 30° C. for continuous cooling. Based on a principle that plasticity of a metal material is reduced after high temperature, the metal wire material 2 is deformed by a strength difference between a front-back drawing force and a back force, and a protective gas in a heating process prevents the metal wire material 2 from being oxidized in a forming process, thereby achieving a continuous and rapid wire drawing process.
A conventional cold drawing process has an area reduction of 10%. If a wire diameter of a brass wire material is drawn from Ø1.2 mm to Ø0.5 mm, about 20 die times (the die times refer to a quantity of times of processes using wire drawing die) are needed, and 6 times or more of annealing and softening processes are further needed. However, referring to
According to the continuous wire drawing apparatus and method of the present disclosure, first, no wire drawing die is needed in a forming process, and die cost can be reduced. Second, no annealing process needs to be performed on a metal wire material after a continuous drawing process, and unnecessary energy consumption can be reduced. Third, the metal wire material is protected by a gas in the thermal forming process, and cannot be oxidized in the thermal forming process. Fourth, a wire drawing process of the present disclosure that improves a design limitation of an area reduction of a conventional wire drawing die, and is applicable to a wire material difficult to form can significantly reduce production cost and promote industrial competitiveness.
The foregoing descriptions only record preferred implementations or embodiments of the present disclosure for presenting technical means used for resolving the problem, but are not intended to limit the scope implemented by the patent of the present disclosure. That is, any equivalent variation and modification made based on meanings of the patent application scope of the present disclosure or according to the patent scope of the present disclosure shall fall within the patent scope of the present disclosure.
