JP2001059684A - Pallet truck of continuous type sintering machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a pallet truck of a continuous type sintering machine, which can be used stably over a long time without sustaining damages such as thermal strain and cracks in an operation in the continuous type sintering machine, and which is inexpensive. SOLUTION: In a pallet truck of a continuous type sintering machine which is composed of a pallet main body 1, a grate bar 2, a sidewall 3 and wheels 4, the material of the pallet main body 1, and the sidewall 3 is constituted of an Fe-C alloy having chemical components of C 3.2-3.6 wt.%, Si 3.0-3.5 wt.%, Mn 0.3-0.6 wt.%, P 0.04 wt.% or less, S 0.02 wt.% or less and Mo 0.51-0.8 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pallet truck for a continuous sintering machine.

[0002]

2. Description of the Related Art A pallet truck generally used in a continuous sintering machine comprises a pallet body, a great bar, sidewalls, and wheels, and the wheels run on rails by being rotationally driven. In addition, a great bar is mounted on the pallet body, and the sintering raw material is placed on this
Air is sucked from above to below the layer of the sintering raw material to ignite the coke in the layer of the raw material. As a result, the upper part of this layer is heated first, the heating area gradually shifts to the lower part, and finally all the layers become sintered ore. When heating is completed, the sintered ore is discharged, and the great bar at the discharge position returns to the original supply position while being cooled. Normally, pallet trucks become hot during operation, so the material is distortion resistance due to heat, cracking and oxidation resistance,
Those having abrasion resistance are used.

[0003] Conventionally, FCD400, which is a spheroidal graphite cast iron, has been used for a conventional great bar in view of operating conditions of a sintering machine, operating conditions of a pallet, and temperature conditions. Also, as described in Japanese Patent Publication No. 60-27748, to minimize distortion, cracking and abrasion due to heat, to improve sintering efficiency and power consumption, and to extend the life of the bogie, There is known a material in which Ni or Mo is added to FCD to increase tensile strength and hardness while ensuring relatively high elongation.

Further, in order to prevent distortion, cracks and wear due to the heat, high-grade materials to which Ni, Cr, Cu and the like are added are used. For example,
C as described in U.S. Pat.
8% by weight, Mn: 0.2 to 0.8% by weight, Si: 1.8
2.8% by weight, P: 0.07% by weight or less, S: 0.0
2% by weight or less, Ni; 2.8 to 3.5% by weight, Mo;
Fe-C alloy materials having a chemical composition of 0.23 to 0.28% by weight are known.

[0005] However, such materials have a problem that the repair cost is increased because the life of the high-grade materials is not extended.

[0006]

SUMMARY OF THE INVENTION The present invention provides an inexpensive continuous sintering machine that can be used stably for a long period of time without causing damage such as distortion or cracks due to heat during operation in a continuous sintering machine. It is an object to devise a pallet truck for a sintering machine.

[0007]

According to the present invention, a pallet body and / or a sidewall of a pallet truck of a continuous sintering machine has a Si content increased based on a ferritic spheroidal graphite cast iron. Further, the material to which Mo was added, that is, the pallet body and / or the side wall of the pallet truck of the continuous sintering machine was C: 3.2 to 3.6% by weight, Si: 3.0 to 3.5% by weight, Mn; 0.3-0.
The problem is solved by comprising an Fe—C-based alloy having a chemical composition of 6 wt%, P: 0.04 wt% or less, S: 0.02 wt% or less, Mo; 0.51 to 0.8 wt%. .

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. 1 and 2, a pallet truck generally comprises a pallet body 1, a great bar 2, side walls 3, and wheels 4. The wheels 4 rotate slowly on rails 5 to continuously move. The pallet is driven to move. According to the present invention, the material of the pallet body and / or the side wall of the pallet truck is improved. That is, according to the present invention, since the content of Si is increased based on ferritic spheroidal graphite cast iron and Mo is further added, it is excellent in resistance to distortion and cracking due to heat, abrasion resistance and impact resistance. Also excellent effects can be obtained. The selection of the chemical components of the material and the basis for the selection will be described below.

In the Fe—C based alloy, C is C weight% determined by the amount of Si, and has a slightly hypereutectic composition. Si is resistant to oxidation, that is, forms an oxide film of SiO _{2 in} an oxidizing atmosphere, and has a performance of protecting the inside. However, if it is less than 3.0% by weight, there is no effect, and if it is more than 3.5% by weight, toughness 3.0% by weight
3.5% by weight.

Mn is 0.6% by weight in a high Si-based material.
If it is larger, toughness and elongation cannot be maintained,
0.3 to 0.6% by weight. P is kept as low as possible as the most harmful crack element as a hot working material, and is set to 0.04% by weight or less. S is an extremely low value as an element that inhibits the spheroidization of the spheroidal graphite cast iron material, and is set to 0.02% by weight or less. Mo is set to 0.51 to 0.8% in consideration of thermal fatigue resistance.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One of the best materials for achieving the object of the present invention within the scope of the above embodiment is specified as follows. Material: C; 3.2 to 3.6% by weight; Si; 3.0 to 3.5
0.3% to 0.6% by weight, P: 0.04% by weight or less, S: 0.02% by weight or less, Mo: 0.51% by weight.
Material in the range of 0.8% by weight. Its properties are 540 N / mm ² or more in tensile strength at room temperature, and this tensile strength is 20 to 30% higher than that of spheroidal graphite cast iron FCD400 in a temperature range of 100 ° C. to 500 ° C. Further, as other mechanical properties, the proof stress is 34.
0 N / mm ² or more and elongation is 15% or more. Further, the metal structure has a graphite spheroidization ratio of 80% or more and a base structure and ferrite of 80% or more.

The dimensions of the pallet truck to be applied are as follows:
For example, the width is about 5 m, the length in the traveling direction is about 1.5 m, the height is about 0.4 m, and the height of the sidewall is 0.65 m. Further, as a use condition, the layer thickness of the sintering raw material to be loaded on the pallet truck is 560 mm, and the temperature of the sinter is about 1300 mm.
° C, the maximum temperature of the truck is 650 ° C, and the speed of the truck is 7 m / min at the maximum. As a result, the material according to the present invention can be manufactured at the same level or less as the conventional material because it does not use high-grade elements, can withstand use for about 12 to 15 years, and has about twice the life as the conventional technique. It was found to extend. On the other hand, a material using a higher element costs 1.5 times as much as the conventional one, but has a life of about 8 to 12 years.

In the above embodiment, an example of one type of use condition of the bogie having one type of dimension has been described. However, the present invention is not limited to this, and it is, of course, used with a conventionally known material. Applicable to all carts.

[0014]

According to the present invention, the FCD base contains a large amount of Si and Mo is added to satisfy the performance required for the pallet truck of the continuous sintering machine.
The use of high-grade elements such as r and Cu is no longer required, and the production can be performed at low cost. In addition, since the high-temperature strength and the mechanical strength were increased, the life was longer than that of the conventional material. In addition, as a result, the operation downtime of the sintering machine was reduced, and the operation rate of the machine was significantly improved.

[Brief description of the drawings]

FIG. 1 is a view showing a pallet truck of a continuous sintering machine according to the present invention, wherein (a) is a plan view thereof, (b) is a front view thereof, and (c) is a line CC of (a). It is sectional drawing which follows.

FIG. 2 is a side view of a pallet truck of the continuous sintering machine shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pallet main body 2 Great bar 3 Side wall 4 Wheel 5 Rail

Claims (1)

[Claims] 1. A pallet truck for a continuous sintering machine, comprising a pallet body (1), a great bar (2), a side wall (3), and wheels (4). ) And / or the side wall (3) are composed of C: 3.2 to 3.6% by weight, Si;
5% by weight, Mn: 0.3 to 0.6% by weight, P: 0.04
% By weight, S: 0.02% by weight or less, Mo: 0.51
A pallet truck for a continuous sintering machine, comprising a Fe-C alloy having a chemical composition of about 0.8% by weight.