JP2873355B2 - Spinning ring - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention is used for spinning of spinning,
In particular, the present invention relates to a spinning ring that exhibits excellent performance in high-speed spinning.

[0002]

2. Description of the Related Art Conventionally, a spinning ring is formed by turning a low carbon steel as a raw material and performing a carburizing and quenching treatment as a surface hardening treatment. However, in the conventional ring, when the spinning speed of the spinning machine is higher than 20,000 rpm, the frictional resistance between the ring and the traveler increases. There was a drawback that continuous operation was not possible. Therefore, in order to solve the above problems, there has been proposed a ring flange in which at least the surface is made of silicon carbide.

However, the improved ring has an aspect ratio of silicon carbide particles of 2 or less, a low fracture toughness K _IC (critical stress intensity factor), and a spindle rotation speed of 2400.
In the ultra-high-speed rotation range of 0 rpm or more, cracks occurred on the ring surface, causing chipping and abrasion, and stable spinning could not be performed for a long period of time. Silicon nitride ceramic is a material having a high fracture toughness K _IC, but has lower heat resistance, lower strength at high temperatures, and lower oxidation resistance than silicon carbide.
In addition, the thermal conductivity and the wear resistance are inferior.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a spinning ring which can operate stably in an ultra-high rotation speed range, has a small wear on the ring, and has a long service life.

[0005]

According to the spinning ring of the present invention, at least the ring flange portion which comes into contact with the traveler uses alumina as a sintering aid and has an average aspect ratio of 2.5.
5 to 5 and is characterized by having a center line average roughness Ra of 0.2 μm or less.

[0006] Normally, in the case of boron-containing sintering silicon carbide, fracture toughness _{K IC} toughness value was low at 2~3MN ^{· m -3/2,} would cause the easily chipping cracked.
Therefore, alumina was added as a sintering aid,
By sintering for a long time (about 10 hours or more) at the temperature of
The formation of a liquid phase mainly composed of alumina promotes densification, and further causes the silicon carbide particles to undergo grain growth, changing from spherical or cubic to plate or columnar, and increasing the aspect ratio of silicon carbide.

[0007] The value of the fracture toughness _{K IC} is less than the aspect ratio of the silicon carbide particles of 2.5 is still low, the value of fracture toughness _{K IC} and of 2.5 or more increases the 4~7MN ^{· m -3/2} If it is 5 or more, it takes too much time for sintering. Further, when the surface roughness of the ring exceeds the center line average roughness Ra of 0.2 μ, the slidability between the ring and the traveler is deteriorated, and not only the yarn breakage at the time of starting frequently occurs, but also the high speed rotation range.
In the ultra-high speed rotation range, the friction resistance index sharply increases,
Premature burning and scattering of the traveler occur, making continuous spinning impossible.

[0008]

Embodiments of the present invention will be described below. 2.5% of alumina as a sintering aid is added to and mixed with silicon carbide powder having an average particle diameter of 1 μm or less, and the mixed powder is put into a ring-shaped mold and press-molded. Next, sintering is performed in a non-oxidizing atmosphere at 2000 ° C. and 1 atm for 15 hours to obtain a ring-shaped silicon carbide ceramic material. (Product A of the Present Invention) As a comparative example, the sintering time of the above-mentioned material was 1 hour (product B of the present invention), 5 hours (product C of the present invention), and 10 hours (product D of the present invention).
And a ring-shaped silicon carbide ceramic material (product E of the present invention) formed with boron as a sintering aid.

The thus obtained material is machined or surface-machined to produce a flange portion 1 of a spinning ring having a surface roughness Ra of 0.1 μm or less and adhered to a body portion 2 as shown in FIG. The spinning ring 3 of the present invention was formed. The body may be made of iron, light metal, resin, or the like.

[0010] The surface roughness is measured according to JIS B06.
The measurement was carried out under the following conditions in accordance with 01-1982. Measurement conditions of surface roughness Kosaka Laboratory Surfcoder SE-30D Cutoff: 0.8 mm Measurement speed: 0.3 mm / sec Measurement magnification: 1000 times Measurement length: 2.5 mm Spinning ring obtained by the above method , A spinning test was performed under the following conditions, and the operation time, the wear amount of the ring and the yarn breakage were measured and compared.

Test conditions Yarn: ester / cotton 45th ring: 3.2 mmF 38 mmφ × 54.0 mm
φ Ring traveler: YS-2 / hf 10/0 (nickel-plated product) Spindle rotation speed: 28000 rpm Figure 2 shows the change in ring wear when operated under the above spinning conditions. The products BD and the comparative product E show the same tendency to wear. After the operation time of 1500 hours, the wear of the comparative product B and the comparative product E starts to increase, and after the operation time of 1800 hours, the wear of the comparative product C and the comparative product D also starts to increase. In the product A of the present invention, the progress of wear is constant. After about 6000 hours of operation, the product A of the present invention had about 1/3 the abrasion wear of the comparative product B and the comparative product E, and the wear of the belling of the comparative product C and the comparative product D was about 1/3. It is about 2 which indicates that spinning can be performed for a longer period.

[0012] The surface condition of the traveling surface of the ring of the comparative product B and the comparative product E after running for about 6000 hours was innumerable fine cracks and many chipping-like chips were observed on the surface. The wear surface of the invention product A was smooth and the generation of fine cracks was small.

The change in thread breakage increases as wear progresses in synchronization with the change in ring wear.
Is very small even after operation for about 6000 hours. This is because the surface of the ring is smooth and the wear of the traveler is small, but the burn and scattering of the traveler are small and a stable sliding state can be maintained.

Further, a test piece is prepared separately, and the fracture toughness is adjusted.
The results of the examination are shown below. K_ICValue MN · m^-3/2  Invention product A 5.6 Comparative product B 2.1 Comparative product C 3.2 Comparative product D 3.9 Comparative product E 2.4 As a result, the higher the fracture toughness, the smaller the ring wear.
It turned out that there were few thread breaks. The sintering aid
The amount of lumina added is preferably 1.5% to 20%, and less than 1.5%.
In the full state, sintering does not proceed sufficiently, and the mechanical strength of the sintered body is weak.
If it exceeds 20%, the properties of silicon carbide will be impaired,
The wear resistance of the ring is low due to the decrease in heat resistance and high-temperature strength.
Down.

[0015]

According to the present invention having the above-mentioned structure, the abrasion resistance of the self-rest of the ring is improved, the thread breakage is reduced, and stable continuous operation can be performed for a long period of time. Moreover, it is an invention having an excellent effect such that the ring traveler does not burn and the life of the traveler can be extended.

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view showing one embodiment of a spinning ring of the present invention.

FIG. 2 is an explanatory diagram showing a relationship between an operation time and a wear amount of a ring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flange part 2 Body part 3 Spinning ring

Claims (1)

(57) [Claims] At least a ring flange portion in contact with a traveler is formed of a plate-like or columnar silicon carbide sintered body having an average aspect ratio of 2.5 to 5 using alumina as a sintering aid, and has a surface roughness. A center line average roughness Ra of 0.2 μm or less.