JPH0634935B2 - Hardfacing method for table liner for vertical grinding mill - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for hardfacing a table liner of a vertical grinding mill.

[Prior Art] As shown in FIG. 3, a vertical crushing mill has a mill housing 13
Grinding table, which can be rotated around the vertical axis at the bottom inside 1
And a plurality of (usually three) crushing rollers 2 rotatable at predetermined positions on the crushing table 1, and while the crushing table 1 and the crushing roller 2 are rotating, the crushing table 1 passes from above the mill housing 13 through the passage 3. The crushed material supplied to the center of the upper surface is crushed, and the primary air supplied from the lower part of the mill housing 13 raises the fine powder to the upper part of the mill housing 13 so that it passes through the coarse powder separator 4 and is discharged from the outlet 5. Has been formed.

In order to enable the crushing table 1 to be used for a long period of time on the upper surface of the crushing table 1 in contact with the crushing roller 2, a plurality of (8 in the figure) divided pieces are arranged in the circumferential direction as shown in FIG.
Attached is a table liner 7 made of ring-shaped wear-resistant material divided into 6,
7 has a plurality of rollers 2 on its circumference.

While crushing the crushed material between the table liner 7 and the crushing roller 2, there may be a problem that the table liner 7 wears faster than the crushing roller 2, and this problem can be solved by solving this problem. In order to improve durability, it is necessary to circumferentially harden and weld a chromium-molybdenum-based alloy, etc., which has better wear resistance than the base material, to the portion of the table liner 7 that contacts the crushing roller 2. It was

Therefore, at the factory, as shown in FIGS. 5 and 6, the surface of each of the divided pieces 6 of the table liner 7 was manufactured by hardfacing welding with a wear-resistant material in an arc shape, and this was crushed. It is conceivable to attach it in a ring shape above. In addition, 8 is a hardfacing part.

[Problems to be Solved by the Invention] However, when the hardfacing welded divided pieces 6 are attached to the grinding table 1 in a ring shape, the adjacent divided pieces are
Since a slight gap 9 is created between 6 and 6, while the crushing table 1 and the crushing roller 2 are rotating, the rotation surface of the crushing roller 2 is impacted by the impact on the corner of the hard facing 8 facing the gap 9 to cure. There was a problem in that a so-called edge chipping, in which a corner of the built-up portion 8 was cut off, occurred.

In view of the above-mentioned circumstances, the present invention is a table liner for a vertical grinding mill that can be hardened and welded to a divided table liner in a circumferential manner without gaps so that an end chip does not occur in a hardened hardfacing part. The purpose is to provide a build-up method.

[Means for Solving the Problem] The present invention has a plurality of divided pieces forming a ring-shaped table liner arranged in a ring shape, and a gap plate having substantially the same height as the divided pieces in a gap between the divided pieces. After the surface of each of the divided pieces together with the gap plate is hardened and welded over the entire circumference in the circumferential direction, the hardened buildup portion and the gap plate of the gap portion are removed to perform the hardfacing welding. Each divided piece is manufactured, then, the divided piece is attached in a ring shape on the mill grinding table, and a gap plate having a height lower than that of the divided piece is inserted into a gap between the divided pieces, and the upper portion of the gap plate is inserted. In addition, the hardfacing welding is performed at the same height as the overlay of the divided pieces.

[Operation] Therefore, it is possible to continuously carry out the hardfacing welding on the table liner without a gap, and to prevent the liner from being chipped due to the crushing of the crushed object.

Embodiments Embodiments of the present invention will be described below with reference to the accompanying drawings.

One embodiment of the present invention will be described with reference to FIGS. 1 (a) to (e) and FIG. 2. In a factory, a plurality of (eight in the figure) divided pieces 6 constituting a ring-shaped table liner 7 are provided. Arranged in a ring shape, insert a gap plate 10 having the same height as the divided pieces 6 into the gaps 9 between the divided pieces 6, and the surface of each divided piece 6 together with the gap plate 10 is made of a material having good wear resistance. For example, a material such as a chromium molybdenum-based alloy is hard-facing welded over the entire circumference in the circumferential direction (first
(A)), and then the hardfacing portion 8 located on the gap plate 10
Is removed by arc air gouging (Fig. 1 (b)), and the gap plate 10 is removed (Fig. 1).
(C)), and manufacture the split piece 6 that is hardfacing welded.

Next, at the site, each of the above-mentioned divided pieces welded by hardfacing is welded.
Attach 6 to ring 1 on grinding table 1 and
A gap plate 11 having a height lower than that of the divided piece 6
, And the divided piece 6 and the gap plate 11 are fixed by welding through a high-toughness welding rod such as a mild steel welding rod 12 (see FIG. 1).
(D)) Radial hardening overlay welding is applied to the upper part of the radially facing gap plate 11 at the same height as the hardening overlay 8 of the split piece 6 (Fig. 1 (e)). Thus, as shown in FIG. 2, a ring-shaped table liner 7 formed by hardfacing welding is formed in a circumferential shape without any gap.

EFFECTS OF THE INVENTION According to the present invention, the table liner is continuously hard-padded without a gap, and therefore, it is possible to prevent the hard-padded portion of the table liner from being chipped while the crushing table and the crushing roller are rotating. It is possible to obtain excellent effects such as extending the life of the liner.

[Brief description of drawings]

FIGS. 1 (a) to 1 (e) are partial cross-sectional views showing the work sequence of an embodiment of the present invention, and FIG. 2 is a plan view of a hardfacing table liner according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of a vertical grinding mill, FIG. 4 is a plan view of a table liner that is not hardened, and FIG. 5 is a plan view of a table liner that is hardened by a conventional method. FIG. 6 is a view on arrow AA of FIG. 5. In the figure, 1 is a crushing table, 6 is a divided piece, 7 is a ring-shaped table liner, 8 is a hardfacing part, 9 is a gap, and 10 and 11 are gap plates.

Claims (1)

[Claims] 1. A plurality of divided pieces forming a ring-shaped table liner are arranged in a ring shape, and a gap plate having substantially the same height as the divided pieces is inserted into a gap between the divided pieces to form a gap plate together with the gap plate. After the surface of each divided piece is hardfacing welded over the entire circumference in the circumferential direction, each hardened overlay welded divided piece is manufactured by removing the hardfacing part and the gap plate of the gap part, and then The divided pieces are attached in a ring shape on a mill grinding table, a gap plate having a height lower than that of the divided pieces is inserted into a gap between the divided pieces, and the overlay layer of the divided pieces is provided on the gap plate. Hardfacing method for a table liner for a vertical grinding mill, characterized by performing hardfacing welding at the same height as.