KR200438020Y1 - Conductor roll coated by fusion spraying of WC series excellent in anti-corrosive property - Google Patents

Abstract

The present invention relates to a spray coated conductor roll having excellent wear resistance and electrical conductivity, and more particularly, to a WC-based spray coated conductor roll device. Compared with the existing SUS 316L conductor roll, it is possible to improve the wear resistance of the roll and to extend the surface hardness and to minimize the damage of the roll, thereby reducing the surface quality defect of the electro-galvanized products by the roll mark.

Description

Spray roll coated by fusion spraying of WC series excellent in anti-corrosive property

Figure 1 shows one embodiment of the present invention is installed thermal spray coated conductor roll on the present invention.

Figure 2 is a schematic diagram of the thermal spray coated conductor roll of the present invention

Figure 3 is a thermal spray coating process for the conductive roll of the present invention

The present invention is directed to a spray coated conductor roll having excellent wear resistance and electrical conductivity.

Conventional conductor rolls used in the manufacture of conventional galvanized (EGL) steel sheets are mainly made of standard SUS316L.However, rolls of this material have frequent product surface defects due to the generation of width marks and squeezable roll marks. It has disadvantages such as loss of productivity due to customer dissatisfaction and downtime of continuous production line due to replacement of damaged rolls.

In particular, in the case of the recent increase in demand for zinc-based conductive anti-fingerprint steel sheets, phosphate anti-finish resin coated steel sheets, which are conventional anti-fingerprint steel plates, have been treated with about 1.6 g / m2 of phosphate chemical coating after galvanizing. By coating, the damaged part by pressing the conductor roll on the back side of the electro-galvanized layer was concealed.However, in the case of zinc-based conductive anti-fingerprint steel sheet, coating the anti-fingerprint resin directly on the plating layer does not cover the defects such as the back of the conductor roll pressing mark. Problems such as not being generated.

Therefore, the present invention can prevent the loss of new roll production due to the improvement of the appearance of the product and the frequent polishing and the reaching of the polishing limit by improving the hardness and durability of the conductor roll for improving the appearance of the back surface of the zinc-based conductive anti-finger steel sheet. As a completely new technology, the rolls made of tungsten carbide (WC) -based spray coatings on the surface of the conductor roll are used to extend the life, reduce the grinding cost, reduce maintenance costs, and reduce the roll replacement time. It aims at bringing the effect of improving quality problems.

In the present invention, in a SUS 316L conductor roll, which is polished and degreasing and cleaned of a roll to be spray coated, the bearing part and the shift part of the roll are masked, preheated with gas, and blasted. After blasting, the surface of the thermal spraying section is adjusted, and after blasting, after air blowing, the surface of the conductive roll is thermally coated with tungsten carbide-based, in particular, WC / CoCr-based coating agent, and after thermal spraying. The main purpose of the present invention is to provide a spray coated conductor roll having excellent abrasion resistance and current conduction, which is formed by cracking the whole yarn and cooling to room temperature by rotating the roll to form an effective spraying layer.

The present invention is mainly spray coating tungsten carbide cobalt chromium (WC-CoCr) based coating on the roll of the steel strip in the galvanizing bath to a thickness of 180 ~ 220 micrometers, resulting in improved hardness and durability, and galvanized steel sheet Provided is a thermally coated conductor roll device that reduces productivity and replacement costs with the conductor roll pressing marks on the back and extended roll life.

1 schematically shows an electrogalvanizing apparatus equipped with a thermally coated conductor roll. 1 shows the technical characteristics of the coating layer and the coating method in which the nine conductive rolls from # 6 to # 14, which are electro-galvanized in the present invention, are thermally coated with the WC-CoCr coating. Is as follows.

After the primary polishing and side PT inspection, calculate the post-spray dimensions according to the primary abrasion and corrosion drawing on the large size grinder and grind them. As the spray pretreatment, degreasing process and washing process are performed. After removing residual oil and contaminants using thinner, blasting is performed as follows after masking bearing part and shift part.

(A) Pre-heating before blast: Using O ₂ / C ₃ H ₈ gas (GAS), heat uniformly with 2000L / HR torch.

(B) Blast treatment: Adjusting the surface of the thermal spraying section in the blasting device (M / C) (Fe-based grit)

(C) After blasting, be sure to clean by air blowing

Before spraying, preheat and pay attention to surface oxidation while paying attention to excessive preheating. Prior to spraying, preheating is 5000 L / HR of O ₂ / C ₃ H ₈ , uniformly heated with several torches and spraying is carried out with plasma and METCO 5P gun (GUN) mounted on an automatic transfer device. As the thermal spraying material, DS-6509-WC-tungsten carbide was used. After treatment, the entire sprayed part is cracked before and after a predetermined temperature, but cooled to room temperature by rotation of the roll. After cooling, the polishing work is carried out and polishing work is carried out according to the drawing of cylinder degree, roundness, straightness, etc. so that the spray effective layer is 180 ~ 220㎛.

As a finishing operation, the mirror polishing operation is performed at a roughness of 0.04 µm to 0.06 µm, and a hardness of Hv 1100 or more and a coating effective hardening layer of 180 µm or more. Final surface treatment was done using DS-SIOB (instead of metalizing agents).

Figure 3 shows one embodiment of a process for producing a roll according to the present invention.

As shown in Fig. 1, the hardness of WC-based CERMET sprayed by HP / HVOF is high. Among them, WC / CoCr, WC / Co, WC / CrC / Ni are high and Hv (200g) = 1190 ~ 1270. 34F is about Hv (200g) = about 950, 16C is about 750.

In terms of dry wear, CERMET was significantly superior to 16C. WC / CoCr exhibits about 14 times higher wear resistance than 16C and about 5 times higher than 34F.

SUGA abrasion test: Abrasion test in which abrasive paper (SiC # 180) is mounted and reciprocated by applying a load between the rotating friction surface and the specimen. The wear ratio with respect to the base material when the wear amount of the base material SS400 is set to 1 is shown.

According to the present invention as described above, it is possible to utilize semi-permanent roll through the roll surface spray coating rather than the conductor roll body polishing method, and the product is frequently damaged due to the reduction of the width mark caused by the complaints, and the roller damage is little during repair. Maintenance costs can be reduced and productivity can be improved without the need for replacement. In addition, since there is no roll surface damage that occurs during friction between strip and conductor roll, there is no defect of conductor roll mark and the demand of conductive anti-finish steel sheet of home appliance makers such as LCD is directly applied to zinc layer. The improvement of the surface appearance of the coated product, namely, the improvement of the back surface of the product and the pressing of the contact surface of the conductive roll, has the effect of satisfying the customer's quality of the produced product through the back quality.

Claims (1)

In the SUS 316L conductor roll, which has been polished, degreasingly cleaned, and roll-coated, the bearing part and the shift part of the roll are masked, preheated by blasting, and blasted by gas. After adjusting the surface of the thermal spraying part, and after blasting, after air blowing, the surface of the conductor roll is thermally coated with a tungsten carbide-based coating, in particular, a WC / CoCr-based coating agent. The thermal spray coating conductor roll having excellent abrasion resistance and current conduction, characterized by cracking but cooling to room temperature by rotating the roll to form an effective spraying layer.

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