JPS5913580B2 - Manufacturing method for oil-less chain bushings - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a push for an oilless chain that has excellent wear resistance.

Conventionally, chain pushers are generally made of Fe-1 to 5% by weight Ni-0.5 to 165% by weight Cl or Fe-1
Although it is manufactured from a low alloy steel with a composition consisting of ~7% by weight Cu and 0.5 to 1.5% by weight C, the low alloy steel does not have sufficient wear resistance. Currently, chains using pushers made of low alloy steel cannot satisfy the elongation of 063%/200hr or less required for chains.

Based on the above-mentioned points of view, this invention has excellent wear resistance and also has the required 0.3%/20
This product provides a manufacturing method using powder metallurgy for a chain push that can satisfy an elongation of 0 hr or less.
Consisting of 2005~1.5%, Cu 1.0~5.0%, Ni 1.0~5.0%, Mo 0.1~1.0%, Fe and unavoidable impurities: the remainder. After producing a porous push material with the same composition, the surface of the porous push material is subjected to a crushing process. , heat treatment of carburizing quenching or carbonitriding quenching is performed on the push material after the crushing process, and this heat treatment is intended to improve the strength and hardness of the push material in close relation to the above-mentioned component composition. Finally, it consists of a basic process of soaking with anti-wear oil, resulting in excellent wear and impact resistance and extremely high fatigue strength. It is characterized by the fact that it produces a push that exhibits excellent performance in many cases.

Next, the reason why the composition of the push material is limited as described above in the method of the present invention will be explained.

(a) CC The C component has the effect of improving the strength by dissolving in the Fe matrix, but if the content is less than 0.5%, the desired strength improvement cannot be achieved; If the content exceeds 0.5%, it becomes brittle and the impact strength decreases, so the content was set at 0.5 to 1.5%.

(b) Cu The Cu component dissolves in Fe during sintering, but precipitates during cooling to strengthen the Fe matrix, so the strength and hardness are improved by the inclusion of Cu, but its content If the content is less than 1.0%, the desired strength and hardness cannot be secured, while if the content exceeds 5.0%, there will be no strength improvement effect, but rather the strength will decrease. Its content was determined to be 1.0 to 5.0%.

(c) Ni The Ni component has the effect of improving toughness, but if its content is less than 1.0%, the desired effect cannot be obtained in this effect; on the other hand, if it is contained in excess of 5.0%, However, the content was set at 1.0 to 5.0%, since no further improvement effect could be seen and the cost would increase.

(d) MO The MO component has the effect of improving hardenability, but if its content is less than 0.1%, the desired effect of improving hardenability cannot be obtained; If it is contained, the hardness will increase, but it will become brittle, resulting in a significant decrease in strength. Therefore, the content was set at 0.1 to 1.0%.

Next, the method of the present invention will be explained using examples.

First, as the raw thorn powder, each commercially available particle size of 100 me
Fe powder of 150mesh or less, C powder of 150mesh or less,
Cu powder, Ni powder, and MO powder were prepared, and these raw material powders were prepared as shown in Table 1. After blending to have the final composition, zinc stearate is used as a lubricant.
4% by weight was added and mixed for 15 minutes using a V-type mixer.

Next, a green compact having a density of 5.9t/Cr/l is formed from this mixed powder, heated to a temperature of 450°C to remove the lubricant, and then ammonia with a dew point of 40″F A porous push material was produced by heating to 1100°C in a cracking gas atmosphere and holding it for 30 minutes for sintering.Then, the resulting push material was charged into a barrel together with media. After the surface portion was subjected to a blinding process, it was heated to a temperature of 850° C. in a normal carbonitriding atmosphere, and oil quenched from this temperature.

After quenching, the oil adhering to the push material is completely removed, and then the outer diameter is reduced to 1 by soaking it with anti-wear oil.
Pushes 1 to 3 according to the present invention having dimensions of 0.1 miφ x inner diameter 5.2 mm x length 13.9 mm, and comparative pushes 1 to 3 whose component composition ranges were outside the range of the present invention were manufactured, respectively. Next, as shown in a partial cross-sectional view in FIG. After inserting the pin 3 into the pin 3, the pin link plates 4 are press-fitted and caulked onto both ends of the pin 3, thereby forming 20 links.
Chains 1 to 3 (hereinafter referred to as inventive chains 1 to 3) using pushes 1 to 3 of the present invention constructed in this way and comparative chains 1 to 3 were manufactured in the same manner, and the resulting chains of the present invention 1 to 3 were manufactured in the same manner. 3 and comparison chains 1 to 3 have a diameter of 15iiφ and a diameter of 30m11, respectively! Spread over two φ sprockets, rotation speed: 2000 rpm, load: 150 kg! A practical test was conducted under the conditions of , and the chain elongation was 0.3.
% was measured.

This is because the frictional wear at the contact portion between the pusher 1 and the pin 3 directly appears as elongation of the chain.
The measurement results are shown in Table 2. As shown in Table 2, all push products of the present invention exhibit excellent wear resistance, so when incorporated into a chain, the elongation required for the chain is O-3%/200hr or less. It is clear that the chain characteristics sufficiently satisfy the following.

On the other hand, Comparative Push had inferior wear resistance and did not exhibit the required chain characteristics when incorporated into a chain. As described above, according to the present invention, a push with excellent wear resistance can be manufactured by using a common powder metallurgy method,
Furthermore, when incorporated into the resulting oilless chain, it exhibits extremely superior chain characteristics.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view of the chain used in the practical test. In the drawing, 1...Push, 2...
・Roller link plate, 3...Pin, 4・
...Pin link plate.

Claims (1)

[Claims] 1 First, by a normal powder metallurgy method, C: 0.5 to 1.5%, Cu: 1.0 to 5.0%, Ni: 1.0 to 5.0%, Mo After producing a porous bushing material having a composition consisting of: 0.1 to 1.0%, Fe and unavoidable impurities: (more than % by weight), the surface thereof is subjected to a blinding process, and then the above-mentioned blinding process is performed. A method for manufacturing a bush for an oilless chain, which is characterized by applying a heat treatment of carburizing and quenching or carbonitriding and quenching to the processed bushing material, and then soaking it with wear-resistant oil.