JPS58136896A - Fabrication of cover roll in papermaking machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a cover roll used in the water squeezing process of wet paper web in a paper making machine.

Wet paper contains 55-80% water, and the P of that water is
Since H is about 3 to 5, the roll used for water squeezing must have corrosion resistance.

For this reason, rolls of this type have either been made of stainless steel or have been covered rolls with the outer surface covered with a layer of stainless steel.

If the roll itself is made of stainless steel, the material cost is high, so the production cost will be lower if the roll is made of a cover roll.

Currently, there are the following methods for manufacturing cover rolls.

As a first example, a wire rod (
Wrapping a) around the core body (b) by applying a tensile force as shown in the same figure (b) is done by tightening it in the axial direction, but the wire material is expensive and special techniques are required for winding. The costs are high.

A second example is one in which stainless steel sleeves of a required length are sequentially butt-sealed onto the core body, and the butt portions are welded. In this cover roll, if the sleeve becomes fatigued, a gap may be formed between the core body and the sleeve and the sleeve may become loose.

As a third example, as shown in Fig. 2, a stainless steel plate (c) of the required width is bent to match the curvature of the core body <b>, and the ends of the keso are welded, and the stainless steel plate (C) is then bent to match the curvature of the core <b>. Seam by welding in the direction 0, then stainless steel plate C
A weld bead (d) is built up in a screw shape on the outer peripheral surface of C), and the weld bead (d) is scraped off after tightening the stainless steel plate (C) and heat treating the weld bead (d). It is.

In this manufacturing process, it is extremely difficult to perfectly match the curvature of the stainless steel plate (C) and the curvature of the core body (6), so when the ends are welded, the stainless steel plate (C) and the core body (A)
A gap is likely to form between the stainless steel plate and the stainless steel plate.

Historically, a common drawback of the second and third examples is that the physical properties of the welded area change and the strength deteriorates, resulting in cracks in the welded area. Also, the heat affected zone is prone to rust. Alternatively, since welding is performed along the circumference, the welded portion may flow, or the cross-sectional rigidity of the welded portion may be low, making it impossible to perform welding with a large amount of heat.

The present invention has been made to solve such problems,
It is characterized in that a corrosion-resistant thin strip-shaped filler metal is sequentially welded and overlaid in the axial direction of the core to form a corrosion-resistant metal layer on the outer surface of the core.

The present invention will now be described in detail with reference to FIG.

+11 is the core of the cover roll, and the core (1) is covered with a thin strip-shaped filler metal (2) made of stainless steel.
Weld overlay in the axial direction of the core body (1).

The weld overlay is carried out in the order of ■-■-■-■ so that the weld overlay points face each other in sequence as shown in FIG. 3, and the entire circumferential surface of the core (1) is covered with the weld metal (3). Then, the weld overlay described above is performed over multiple layers to form a stainless steel layer of the required thickness.The overlaid core body (1) is then heat treated to remove residual stress and finish the surface. Let's make a roll.

According to the present invention, since the stainless steel layer is entirely made of welded metal, there is no non-uniformity in the material, the bond between the stainless steel layer and the core is extremely strong, and the weld overlay is applied in the axial direction. This allows the core to maintain its rigidity during welding.

According to the present invention, a cover roll with high reliability and visibility is manufactured at low cost.

In the above embodiment, the filler metal is made of stainless steel, but it goes without saying that it may be made of other metals that have good corrosion resistance.

[Brief explanation of drawings]

Figures 1 (a) and (b) are explanatory diagrams of the first example of the conventional cup roll manufacturing method; Figure 2 is an explanatory diagram of the third example of the same method;
The figure is an explanatory diagram of the roll manufacturing method according to the present invention. (1) shows the core body, (2) shows the filler metal, and (3) shows the welded metal. Patent applicant Ishikawajima Harima Heavy Industries Co., Ltd.

Claims (1)

[Claims] l) Manufacture of a cover roll for a paper machine characterized by sequentially welding and overlaying corrosion-resistant thin band filler metal in the axial direction of the core to form a corrosion-resistant metal layer on the outer surface of the core. Method.