JPS6142415A - Continuous drawing method of wire rod - Google Patents

Abstract

PURPOSE:To obtain a film excellent in thermal resistance and to perform drawing efficiently by making ultrasonic treatment to ensure the quantity of adhesion of film of zinc calcium phosphate and to control the quantity of adhesion. CONSTITUTION:Drawing is made by performing descaling, preliminary lubricating processing and lubricating processing while moving a wire rod continuously. At this time, descaled and then preheated wire rod is passed through a zinc calcium solution (Ca/Zn=0.3-1) kept warm at 70-90 deg.C and applied by ultrasonic wave (frequency: 10-60kHz, output; 25W/1L solution) for preliminarily lubricating process. After washing with water, calcium stearate is made to adhere to preliminarily treated wire rod at room temperature or, the wire rod is passed through sodium stearate solution warmed at 70-90 deg.C for lubricating process. Then it is dried and drawn.

Description

Detailed Description of the Invention Technical Field of the Invention The present invention relates to continuous drawing of wire rods for cold forging, in which wire rods (including steel bars) are continuously moved and subjected to descaling, lubrication surface treatment, and lubrication treatment. Concerning line methods.

Conventional technology and its problems Secondary processing of wire rods for cold forging involves descaling of wire rods.
/L/(Pickling) - The steps are carried out in the following order: drying, surface treatment, lubrication, drying, stretching, and winding. The pickling, lI surface treatment, and lubrication treatment are generally performed by a patch treatment method. That is, conventionally, after pickling the wire, it is immersed in a phosphate solution such as zinc phosphate, and then immersed in an aqueous solution such as sodium stearate to coat the surface of the wire with a solution such as zinc stearate or zinc phosphate. This method forms a lubricating film. Conventionally, this patch treatment method has been adopted because it takes a long reaction time to obtain a film thick enough to exhibit sufficient lubrication performance, and in order to do so, the treatment tank must be made longer. This is due to reasons such as reeds and difficulty in converting to on-fin.

Therefore, for example, in Japanese Patent Application Laid-Open No. 56-163047,
With the aim of improving equipment costs and productivity, a method has been proposed that allows for lubrication base preparation and lubrication treatment to be carried out online.
It has already been put into practical use. This method, after descaling,
At room temperature, μsium stearate is applied to the surface of a wire rod that has been treated with a zinc phosphate film (lubrication treatment) (lubrication treatment).
The lubricant is characterized by rapid drying after drying, which reduces cleaning costs, and allows the required amount of lubricant to be applied in a short time. On-fin construction is possible without major extension.

However, in both the patch treatment method and the on-fin method, the conventional method uses a zinc phosphate solution as a lubricating base agent, which has the disadvantage that the heat resistance of the lubricating film is poor.

Purpose of the Invention This invention brings wire rod descaling, lubrication base treatment, lubrication treatment, drying, and wire drawing processing online, obtains an F14 slip coating with excellent heat resistance, and makes wire drawing more efficient than ever before. The purpose of this paper is to propose a t1 method that can be implemented in a short period of time.

Structure of the Invention In the continuous wire drawing method according to the present invention, a preheated wire after descaling is kept at a temperature of 70 to 90°C and subjected to ultrasonic waves (frequency a: 10 to 60 KH2, output + 25 W/mff1).
Zinc phosphate solution (Ca/per) added
/Zn = 0.3 to 1.0), and after rinsing with water, calcium stearate is adhered to the wire material with the surface treatment at room temperature, or the wire material is kept at a temperature of 70 to 90°C. It is characterized by performing a lubrication treatment by passing it through a sodium nutearate solution, followed by drying, and at the time of wire drawing, 1 to 10% by weight of a lubricant mainly composed of metal soaps is added as a pre-dyne lubricant. thermoplastic resins (e.g. Teflon, polyethylene, nylon,
It is characterized by the addition of acrylic, polycarbonate, etc.).

This invention will be explained in detail below.

First, the method for descaling the wire in the present invention is not particularly limited, and may be any of the pickling method, the Schottp method, and the roll bending method. Among these, the shot-plast method is suitable for online production in order to secure a phosphate film.

Next, as a lubricating base treatment agent, this invention uses a zinc calcium phosphate solution (Ca/Zn=0.3~
1.0). That is, the temperature of the decrystallization water for the zinc phosphate calcium film is 415°C, whereas the temperature of the decrystallization water for the conventionally used zinc phosphate film is 280-290°C. Therefore,
Zinc phosphate film generates heat during wire drawing (200-300℃) K
It becomes more decrystallized water. For this reason, cracks tend to occur in the coating during wire drawing. On the other hand, in the case of the zinc calcium phosphate coating of the present invention, since the temperature of the decrystallization water is 415° C. as described above, the coating is unlikely to crack during wire drawing.

Further, the present invention is characterized in that ultrasonic treatment is carried out in order to ensure the amount of adhesion of the zinc calcium phosphate film and to control the amount of adhesion. As for keratosis, it is difficult to secure a sufficient amount of adhesion because the chemical conversion treatment property of the zinc phosphate calcium solution is slightly worse than that of the zinc phosphate solution. However, as shown in Figure 1, which shows the effect of ultrasonic waves, adding ultrasonic waves to the zinc phosphate solution increases the amount of adhesion, so a method of adding ultrasonic waves to the lubrication base treatment was adopted. It is. The results shown in Figure 1 are based on the processing conditions: concentration 160 points, temperature 80°C, ultrasonic frequency 50KHz, IKW.
This is the case.

In addition, the above-mentioned ultrasonic frequency is 10 to 6
0KH2 is desirable. This is because if IQKH2 or less, there is a problem in terms of contrast, and if IQKH2 or more, it does not have much effect on the amount of adhesion. Furthermore, the output power is 25W per solution 11
is preferred.

Further, the reason why the Ca/Zn ratio of the zinc calcium phosphate film was set to 0.3 to 1.0 is as follows. Third
The figure is a chart showing the relationship between the Ca/Zn ratio and the amount of adhesion in a zinc phosphate A/V film (solution concentration 160 points). That is, when the Ca/Zn ratio becomes 0.3 or less, Ca
Since the ratio of Ca is small, the effect of Ca addition is small and the heat resistance is insufficient. In addition, if Ca/Zn>1.00, the chemical conversion treatment property is poor and the predetermined phosphate adhesion amount (≧6f//),
It is difficult to obtain a metal soap adhesion amount (≧1 f/d). Therefore, the Cm/Zn ratio of the zinc phosphate 14/Vium film is preferably 0.3 to 1.0.

Note that unless the concentration of the zinc phosphate/I/V um solution is 160 points or more, a predetermined adhesion amount of 6 f/r1 or more cannot be obtained in a short time treatment of 10 to 20 seconds. Also, 2
If it exceeds 00 points, the amount of adhesion cannot be obtained even though the concentration is increased, which is not economical. By the way, the reason why the predetermined adhesion amount of the zinc calcium phosphate film is 6 f/d or more is because
In the case of the conventional zinc phosphate film, it is necessary to set the prescribed deposition amount to 7 to 8 f/rl because of its poor heat resistance, but in the case of the zinc phosphate calcium film of the present invention, it has excellent heat resistance. This is because 6f/ly/ is sufficient.

The lubrication treatment to be carried out after the above-mentioned lubrication base treatment is:
The process is characterized by passing through a storum stearate solution kept at a temperature of 0 to 90°C.

In the case of the strongium stearate treatment (ii), as is clear from the relationship between the concentration and the amount of adhesion shown in Figure I/C4, the concentration is 300f/1 in order to make the amount of adhesion more than the predetermined 5f//.
That's all. The method for attaching calcium stearate to the wire is the wet spray method (applying a solution).
Alternatively, a dry coating method (powder coating) can be adopted, but a wet coating method is preferable in view of the amount of lubricant deposited, the W antecedent of the film, etc. Note that the processing time is usually about 2 to 3 seconds because of physical adhesion.

In addition, in the case of the sodium stearate treatment (■), a batch method can be adopted, but in this case, the reaction layer (stearin (zinc acid) will be attached. The amount of this reaction layer deposited is usually 1 f/n? It is necessary to secure the above (To)
The treatment time required for this purpose is 20 seconds or more based on the relationship between the sodium stearate treatment time and the amount of reaction layer deposited as shown in FIG.

Note that the above lubrication treatments (1) and (2) can be omitted if a pre-die lubricant is added during wire drawing.

In this invention, the pre-die lubricant is added during wire drawing in order to further improve the heat resistance and lubricity of the lubricant film. 1 to 10% by weight of a thermoplastic resin (for example, Teflon, polyethylene, nylon, acrylic, polycarbonate, etc.) is used. The reason why thermoplastic resins are added to lubricants for metal soaps is to take advantage of the heat resistance and low friction properties of thermoplastic resins such as Teflon. In addition, the addition amount is limited to 1 to 10% by weight, because if it is less than 1%, the effect of adding Km such as pulling force is not so noticeable.On the other hand, as the addition amount increases, the effect can be obtained, but cracked gas such as Teflon In this case, the upper limit was set to 10 in consideration of the fact that it was a fluorine gas and the cost.

FIG. 6 is a block diagram showing the processing steps of the present invention.

Tohiko: The wire rod is unwound from a payoff stand (1) and descaled by, for example, shot blasting in a descaling step (2). Subsequently, a zinc calcium phosphate solution (Ca/Zn = 0.3~ 1.0) Lubricating base treatment is performed through the inside. The zinc calcium phosphate solution is preheated to a temperature of 70-90°C. Next, through a water washing step (5), in a lubrication treatment step (6), calcium stearate or sodium stearate is applied to the wire rod which has been subjected to the lubrication base treatment, and is then subjected to a lubrication treatment. The stearate treatment is carried out at room temperature; in the case of sodium stearate, the solution is preheated to a temperature of 70-90°C. After this lubrication treatment, the ξ wire is dried (7)
After sufficiently drying the lubricating film, the wire drawing process (8)
A lubricant is added before the die, the wire is drawn, and the wire is wound up in a winding device (9).

Here, as a device for performing the ultrasonic lubrication base treatment, as shown in Fig. 7 and 's8, for example, a plurality of ultrasonic application devices (up, down, left and right) are installed on the outer peripheral surface of the cylindrical treatment tank 0υ. The return pipe Q4 is arranged in two places parallel to each other in the direction (of course, they can be arranged at different positions), and the return pipe Q4 is connected from the inlet and outlet of the processing tank ) is installed in the west of the processing liquid tank to collect the processing liquid fil, and the processing liquid in the processing liquid tank (to) is supplied via a pump (1iK to the processing tank αIK). can be used.

According to such a device, ultrasonic waves are irradiated into the zinc calcium phosphate solution to stir the solution, and the cavity V
The zinc-calcium phosphate solution quickly adheres to the surface of the wire due to the ion action. Furthermore, the amount of deposited zinc calcium phosphate solution can be controlled by changing the presence or absence of ultrasonic wave application or the frequency and output of the ultrasonic wave application device.

EXAMPLE With the fin configuration shown in Fig. 6, shot blasting was used to descale the wire rod, and equipment equipped with the ultrasonic lubrication and surface treatment equipment shown in Figs. The material (material 545c) was drawn under the operating conditions shown below,
Finally, wire drawn materials of 4.95 mφ and 4.6 mφ were obtained.

Operating conditions ■Descaling conditions Abrasive material Nistybo/l/0.31φ, projection density:
Approximately 300Kli/rl ■Preheating conditions Steam spraying: Preheating temperature 80℃ ■Lubricating base treatment conditions Lubricating base agent Zinc diphosphate power) vv um solution (Ca/Zn
=0.5) Adhesion conditions: 160 points (concentration) x 80°C (temperature) x
15 sec (reaction time), ultrasonic wave: 50 KHz, l
KW ■Lubrication treatment conditions (1) When stearic acid power is 1vVum, concentration: 301/
/, 1 degree: room temperature 1 hour = 3 seconds (1) In case of sodium stearate concentration: 90f/1. Temperature: 80℃ 9 hours: 25 seconds ■Drying conditions Infrared drying oven: Molten metal 80℃ ■Wire drawing conditions Lubricant before die A lubricant whose main component is calcium nistearate with 3% Teflon added Area reduction rate: Approximately 19% (5.5■φ→4.95fieldφ) Approx. 30
% (5,5 field φ → 4.6 ■φ) Wire drawing speed = 80 solutions/i Table 1 shows the drawing force during wire drawing using the conventional method (lubricated base treatment zinc diphosphate, dynu pre-lubricated Nistearin). This is a comparison with a commercially available lubricant whose main ingredient is calcium chloride.

In addition, Figure 9 shows the results of the Bowden test (survey of lubrication ability and oil film adhesion) of the wire rod after winding, and Table 2 shows the number of Bowden sliding operations to reach μ = 0.2, in comparison with the conventional method. show.

In addition, the conditions of Invention Example 1 (however, wire drawing area reduction rate: 5.5φ
Table 3 shows the life expectancy of wire drawing dies and cold forging dies compared to conventional ones when wire is drawn at 4°95φ) and machine screws are manufactured by cold forging.

Table 1 Pulling force Table 2 Bowden sliding number (μ=0.2) Table 3 Life of wire drawing dies and molds However, the lifespan of dies and molds is limited to the lifespan of dies and molds until they are replaced due to wear, damage, etc. From Tables 1 and 2 and FIG. 9, it can be seen that the lubricating film according to the present invention is superior in both I## heat resistance and adhesion compared to the conventional zinc phosphate film. Therefore, it can be seen from Table 3 that the life of wire drawing dies and cold forging dies is greatly extended.

As explained in detail, the method of this invention uses zinc phosphate as a lubricant surface treatment agent, thereby creating a film with higher decrystallization water temperature and superior heat resistance than the conventional zinc phosphate film. In addition, by employing the ultrasonic application means, the amount of the zinc phosphate Cal Vf1 coating can be secured and controlled at will. moreover,
Above fI411! ! Add stearic acid on top of the base treatment agent.
M scrap treatment with sodium or sodium stearate has the effect of improving not only heat resistance but also lubricity. In addition, by using a lubricant in front of the die during wire drawing, which is a mixture of conventional lubricants mainly made of metal soap and thermoplastic resin such as Teflon, the heat resistance and lubricity of the lubricating film are improved. This has the effect of greatly extending the life of cold working tools.

[Brief explanation of drawings]

Fig. 1 is a chart showing the effect of adding ultrasonic waves in the lubricating base treatment of the present invention, Fig. 2 is a chart showing the relationship between the ultrasonic frequency and the zinc phosphate p-sium adhesion amount in the above.
The figure shows the Ca/Z of the zinc calcium phosphate film in the same manner as above.
A chart showing the relationship between the n ratio and the amount of adhesion, Fig. 4 is a chart showing the relationship between the concentration of calcium stearate and the amount of adhesion in the same as above, and Fig. 5 shows the treatment time of sodium stearate and the amount of reaction layer adhesion in the same as above. FIG. 6 is a block diagram showing the processing steps of the present invention, FIG. 7 is a schematic side view showing an example of the apparatus for performing ultrasonic lubrication base treatment in the above, and FIG. 8 is the same apparatus as in the above. FIG. 9 is a schematic front view showing the processing tank of FIG. 1... Payoff free μ, 2... Descaling process, 3... Preheating process, 4... Lubrication base treatment process, 5
...Water washing process, 6...Lubrication treatment process, 7...
・Drying process, 8... Wire drawing process, 9... Winding device, 11... Processing tank, 12... Ultrasonic application device,
13... Processing liquid receiver, 14... Return pipe, 15...
...Processing liquid tank, 18...Wire rod, 19...Processing liquid. (P/l) I take 1=)”tsu・oz a'l (+(
Z"/l) it'A) (uZ deception y-fi z-
Af ) 恢口 Yfd ward ~ 翫大す椰・诺满扠(P/lj) 48 Cao Liangan, IJz leading scene '4 (outside / 3) 凋'' 啄fold J tate My-++c≠7(P //13
)li hot#”:)-UZIJ'y(I1N opening aG1-
42415 (7) Skin' + 3 passageways

Claims (1)

[Claims] 1. In a method of descaling, lubrication undercoating, and lubrication treatment while continuously moving the wire, the preheated wire after descaling is kept at a temperature of 70 to 90°C and subjected to ultrasonic waves. (Frequency: 10-60KHZ, Output: 25W/per liter of solution)
/Zn=0.3-1.0), and after rinsing with water, calcium stearate is applied at room temperature to the wire after the base treatment, or the wire is heated to 70%
A method for continuous drawing of a wire, characterized by passing it through a sodium stearate solution kept at a temperature of ~90°C for lubrication treatment, and drawing after drying. 2. In a method of wire drawing after descaling, lubrication base treatment, and lubrication treatment while continuously moving the wire, the preheated wire after descaling is kept at a temperature of 70 to 90°C and subjected to ultrasonic waves (frequency: 10 to 60 KHZ). ) Output: 25W/per liter of solution)
/Zn=0.3-1.0), and after rinsing with water, the wire rod with the base treatment was placed in a calcium stearate solution kept at room temperature, or 70-90%
Lubrication treatment is carried out by passing it through a sodium stearate solution kept at a temperature of A continuous wire drawing method characterized by adding additives.