JPH0362786B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a plating apparatus, particularly a hot melt plating apparatus for performing thick plating.

<Conventional technology> Methods for producing plated materials can be roughly divided into melt plating methods and electroplating methods.The former is relatively fast, uses simple equipment, and is effective in forming a plated layer with a low melting point. Although this method is suitable, there is a limit to the increase in the thickness of the plating layer, and it is difficult to form a thick plating layer with good surface quality.

The latter allows thicker plating with less uneven thickness, and it is also possible to plate materials with high melting points, but the plating speed is slow and it is not economical in terms of manufacturing equipment and plating bath costs. In addition, the surface hardness may be lower than that of melt-plated materials, which may cause problems in the process of using the plating materials.

It has been desired to develop an apparatus that can produce stable products of uniform quality by melt plating, which is more economical than electroplating.

<Problems to be Solved by the Invention> The purpose of the present invention is to solve the above-mentioned drawbacks of the prior art, and to provide a hot-melt plating method for producing a plated material with good surface quality when thick plating is performed using the hot-melt gluing method. The goal is to provide equipment.

<Means for Solving the Problems> The present invention provides a wire or strip melt welding device in which a laminar flow of molten metal is applied around the compared wire or strip along the running direction of the covered wire or strip. The object of the present invention is to provide a melt plating apparatus characterized in that it has a forced circulation means for flowing the plating line or strip in a vertical direction and performs melt thick plating by running the line or strip to be plated in a vertical direction.

<Configuration of the Invention> The configuration of the invention will be described in detail below using drawings showing preferred embodiments of the invention.

FIG. 2 is a schematic diagram showing a conventional melt welding line. The core wire 2 that has been pretreated in a predetermined pretreatment tank 3 enters the plating bath, passes through a hole in a die 5 with a plating layer of molten metal 4 on its surface, is pulled upward, and is pulled up into a winder 7. It is wound up by.
When the plating layer is relatively thick (approximately 5 μm or more), due to factors such as gravity, vibration, and uneven cooling conditions, the plating layer may spread in the longitudinal direction and circumference of the core wire on the core wire surface until the plating layer solidifies. Since it tends to flow non-uniformly in the direction, local variations in plating thickness occur and the smoothness of the surface condition is lost. In particular, as shown in Figure 3,
The molten metal 4 directly below the die 5 generates convection due to the speed of the plated wire 2, which tends to cause uneven plating due to die wobbling.

FIG. 1 shows an example of the configuration of the apparatus of the present invention, which improves the drawbacks of the conventional method.

The melt plating device 12 of the present invention has a plating thickness of
A vertical melt gluing device in which the core wire 2 runs in a vertical direction and is intended for thick plating of 5 μm or more,
A core wire supply cap 10, a molten metal channel 11 that allows the core wire 2 supplied through the core wire supply cap 10 to travel in a vertical direction in the center, and a molten metal channel 11 that allows the core wire 2 to be passed through the molten metal channel 11 to be used as a covered metal. It has a die 5 for controlling the amount of molten metal plated on the core wire 2, and a molten metal circulation machine 9 for forcibly circulating the molten metal 4 in a laminar flow state along the running direction of the core wire 2.

As the core wire supply cap 10, any conventional cap can be used.

The molten metal flow path 11 forms a closed circulation path for the molten metal 4 together with a molten metal circulator 9 as a forced circulation means for the molten metal 4, and the molten metal circulator 9 flows around the core wire 2 in a laminar flow state. The molten metal 4 is forced to circulate at a desired speed so that it flows in the same direction as the running direction. Running speed of core wire 2 and molten metal 4
The relative flow velocity of can be selected differently by the molten metal circulator 9 so that the molten metal 4 flows in a laminar manner around the core wire 2. In particular, it is preferable that the running speed of the core wire 2 and the flow speed of the molten metal 4 be the same. The molten metal channel 11 has a uniform wall thickness of 5 μm by making the cross section as narrow as possible if it is at least 5 times the diameter of the core wire and by controlling the temperature accurately.
It is possible to apply a thickness of m or more.

By having the above-mentioned configuration of the molten gluing apparatus of the present invention, the temperature of the molten metal 4 with which the core wire 2 is in contact becomes uniform, the plating thickness becomes uniform, and thick plating with stable quality can be obtained. can.

The molten metal circulation machine 9 has the above-mentioned molten metal flow path 11.
At the same time, it is sufficient that the molten metal 4 can be forcedly circulated around the core wire 2 so as to flow in a laminar flow in the same direction as the running direction of the core wire 2, and a normal pump for high-temperature metals can be used. Although not shown, the molten metal 4 can be supplied continuously or at regular intervals to replenish the molten metal 4 lost due to plating, so that a constant amount of molten metal always flows through the molten metal channel 11. Let it flow.

The dice 5 may be any conventional dice.

To optimally select the length of the molten metal flow path 11, the core wire running speed, and the molten metal set temperature for the diameter and material of the core wire 2, which is the material to be plated, and the type of the molten metal 4, which is the plated metal. Thick coating can be achieved by The plating conditions are calculated theoretically taking into consideration the transfer of heat, and are determined by making practical corrections through various experiments.

The plating process using the melt gluing device of the present invention is performed by using a core wire 2 fed out by a feeding device 1.
is wound up by the winder 7 and runs vertically at a desired speed. A melting and gluing device 12 is connected between the feeding device 1 and the winding device 7 via the processing tank 3.
A cooling tank 6 is installed adjacent to the die 5 of the melting and gluing device 12.

The core wire 2 passes through a core wire supply mouthpiece 10, passes through a molten metal fluid that is made into a laminar flow state in the same direction as the running direction of the core wire 2 by a molten metal circulation machine 9, is narrowed to a predetermined size by a die 5, and immediately after passing through the die. Cooling tank 6 in
It is cooled to form a plated wire 8.

<Example> Annealed copper wire with a diameter of 0.50 mmφ was coated with Sn60% at 240±5℃.
Hot-dip plating was performed using a 40% Pb solder melting metal bath. Core wire running speed 50cm/sec, molten metal flow rate
A parallel flow of 40 cm/sec was used, and a die diameter of 0.60 mmφ was used.

The resulting plating line had no uneven thickness and had a smooth surface with a plating thickness of 0.025 mm.

<Effects of the Invention> The molten gluing apparatus of the present invention is a molten gluing apparatus that performs molten gluing by running a metal wire or strip to be plated in a vertical direction for the purpose of thick plating. Since the metal flows around the wire or strip in the same direction as the running direction, preferably at the same speed, the temperature of the molten metal in contact with the wire to be plated becomes uniform, and the plating thickness becomes uniform. A thick wire with stable quality can be obtained.

In particular, when the molten metal travels at the same speed as the core wire, the metal around the core wire solidifies during that time, and the heat is absorbed by the low-temperature core wire, making it possible to build the material as thick as 0.030 mm.
In the conventional method, the high-temperature molten metal contacts the core wire in a turbulent state, resulting in high temperatures and the upper limit of the plating thickness to be several microns.

In addition, by circulating the molten metal through a relatively narrow flow path, it is possible to control the temperature with good responsiveness, making it easy to set thick walls and uniform conditions.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the melt-plating apparatus of the present invention. FIG. 2 is a sectional view of a conventional melt-plating line. FIG. 3 is a detailed view of the vicinity of the dice in FIG. 2. Explanation of symbols, 1... Feeding device, 2... Core wire, 3... Pre-treatment tank, 4... Molten metal, 5... Dice, 6... Cooling tank, 7... Winding machine, 8... Me Wire, 9... Molten metal circulation machine, 10... Core wire supply mouthpiece, 11... Molten metal channel, 12... Melt plating device, 13... Molten metal convection (conventional example).

Claims (1)

[Claims] 1. An apparatus for hot-melting wires or strips, having forced circulation means for flowing molten metal in a laminar flow around the wire or strip to be plated along the running direction of the wire or strip to be plated, and A melt plating device characterized by performing melt thick plating by running a line or strip to be plated in a vertical direction.