JPS61287457A - Crusher hammer - 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 (Field of Industrial Application) The present invention relates to a crusher hammer used in a crusher for coal, rock, etc.

(Conventional technology) COM (Coal Oll Mixture) and CWM
In the process of manufacturing fuel such as (Coax Water Mixtur
crusher) is used.

Fig. 2 shows the structure of the crusher, body) is the rotary desk, (b) K is attached to the nozzle, (C) is the breaker plate), (d) is the grate, and (g) is the raw material on the crusher body. This is a coal feed port that supplies charcoal.

Coking coal is supplied from the coal feed port (=) and is crushed by colliding with the hammer (α) K attached to the rotary disk (bl) rotating at approximately 100°rpm. The coal collided with α) and crushed further into the breaker (
It also collides with C) and is crushed. The crushed coal is further crushed between the hammer (α) and the grate (d), passes through the gap between the grate (d), and exits the crusher.

In such a crusher, the crushing surface of the hammer (α) is severely worn, so the conventional material for the hammer (α) is Ni -Or - which has been hardened to a Vickers hardness of about Hv550 by heat treatment. M□Using cast steel or 1. Alternatively, hardfacing welding was applied to the fractured surface of the hammer electric.

Figure 3 shows a crusher hammer with conventional hardfacing welding, where the hammer body (7'1 is made of Ni -
It is made of Or-Mo cast steel, and a hardened overlay metal (g) having a shore hardness of Hs85 is layered on the fractured surface of the hammer body.

(Problems to be Solved by the Invention) Conventional heat-treated cast steel hammers are not sufficiently effective against the severe wear caused by crushing coal, etc., and the maximum wear depth is reduced after approximately 100 hours of operation. When the length reached approximately 10m5m, the coal crushing performance deteriorated and it had to be replaced with a new one, which was a huge time and financial burden.

Further, even when hard overlay welding is performed on the fractured surface of the hammer, hard overlay welding with low hardness is ineffective against wear, so hard overlay welding with high hardness is required. However, in this case, if the thickness of the hardfacing metal is increased, peeling cracks will occur, so the thickness is usually limited to about 10m11, and because the thickness of the hardfacing metal is small, wear is caused by low hardness. The wear progresses to the base metal, and the wear progresses at a very rapid rate thereafter. Therefore, even when hardfacing welding is performed, it is not very effective in improving the life of the hammer. FIG. 4 shows the state of a conventional hardfacing welding hammer after it has been operated for approximately 100 hours, and (A) shows the portion that has been consumed due to wear.

In this way, the wear resistance of hammers used in severe abrasion environments is a factor that greatly influences the performance and quality of crushers, and hammers that wear out quickly require a lot of time and money to replace. However, since the operating efficiency of the crusher also decreases, there has been a strong desire to develop a wear-resistant hammer with a long service life.

(Means for Solving the Problems) The present invention has been proposed to solve the above problems.

This relates to a crusher hammer characterized in that a groove extending in a direction perpendicular to the rotational direction of the hammer is provided near the tip, and a hardfacing weld metal layer is formed on the groove and the surface of the crushing surface. .

(Function) Wear of the crusher hammer according to the present invention progresses in the depth direction and circumferential direction from the end of the hardfacing metal on the surface of the crushing surface, and when the thickness of the hardfacing metal is worn away. The base material is exposed.

When the base metal is exposed in this way, the wear rate increases, but the wear part immediately reaches the hardfacing weld metal layer formed in the groove provided near the edge of the crushing surface of the hammer top, and wear occurs in the same layer. is suppressed.

Further, since the hard overlay weld metal layer formed in the groove portion has a relatively small overlay thickness on both sides of the force ζ groove where the overlay thickness becomes large, its peeling resistance is good.

(Effects of the Invention) According to the present invention, a groove extending perpendicularly to the rotational direction of the hammer is provided on the surface of the top crushing surface of the hammer near the tip, and hardfacing is applied to the groove and the surface of the crushing surface. By forming the weld metal layer, the hardfacing welding metal layer in the groove is thickened (thus suppressing the progression of wear to the base material, and the peeling resistance of the hardfacing welding metal layer is compared with conventional ones. This is equivalent to the case of a thin hardfacing weld metal layer.

(Example) The present invention will be described below with reference to the illustrated embodiments.

(1) is the Talara Shahammer body, Ni-0r-M
o It is made of cast steel that has been quenched and tempered to have a Vickers hardness of Hv 260.

A groove (2) extending in a direction perpendicular to the rotational direction of the hammer body (1) is provided near the tip of the surface of the top crushing surface of the hammer body, and the groove (2) and the surface of the crushing surface are hardened. An overlay weld metal layer (3) is formed.

The chemical composition of the hardened overlay weld metal is C...0.5 cm (weight ratio, the same applies hereinafter) Cr-25%, Nb-3,0
%.

Mo...25 staff, W...3.5 staff, ■...1.0
It has a surface hardness of approximately Hs85 in Shore hardness, and is formed to a thickness of 8 mm by covered arc welding.

Wear of the hammer progresses from the end of the hardfacing weld metal layer (3) in the depth direction and in the circumferential direction, and when the thickness of the hardfacing weld metal layer (3) is worn, the base material is damaged. A stone to put out.

If the base material is exposed in this way, the wear rate will be rapid (but the groove (21) provided near the end of the hammer body (1) will immediately
A hardfacing weld metal layer (reaching 311C) formed on

Wear is suppressed by the same layer (3).

Hardfacing weld metal layer (3) formed in the groove (2)
) has a thick build-up thickness (although the build-up thickness on both sides of the groove (2) is relatively small, so its peeling resistance is good).

When the crusher hammer was actually operated for about 400 hours, it was found that the hard overlay weld metal layer (3) did not peel off and the wear life was three times that of the conventional crusher hammer.

Although the present invention has been described above with reference to embodiments, the present invention is of course not limited to such embodiments, and the design of the seed drawer may be modified without departing from the spirit of the present invention. be.

[Brief explanation of drawings]

FIG. 1 is a side view of an embodiment of a crusher hammer according to the present invention, and FIG. 2 is a longitudinal sectional side view of the crusher. FIG. 3 is a side view of a conventional crusher hammer, and FIG. 4 is a side view showing its wear condition. (1)...crusher hammer body, (2)...groove,
(3)...Sub-agent for hardfacing welded metal Patent attorney Shigefumi Okamoto, 7, and 2 others Figure 1 Figure 2

Claims (1)

[Claims] A groove extending perpendicularly to the rotational direction of the hammer is provided on the surface of the top crushing surface of the hammer near the tip, and a hardfacing weld metal layer is formed on the groove and the surface of the crushing surface. A crusher hammer.