CN100460144C

CN100460144C - Method for processing sewing-machine rotating shuttle to be wear-resistant

Info

Publication number: CN100460144C
Application number: CNB2006100404392A
Authority: CN
Inventors: 朱桂成
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-05-08
Filing date: 2006-05-08
Publication date: 2009-02-11
Anticipated expiration: 2026-05-08
Also published as: CN101069945A

Abstract

It is a wearing preparation method of the sewing machine rotating shuttle. The rotating shuttle uses 38CrMoAl materials for forging, roughing and finishing. Then, put them into the heat treatment furnace for isothermal heat of adsorption nitriding and the temperature is controlled at 480deg.C-520deg.C. Keep the temperature for 15hs under the 18-25% ammonia dissociation rate and keep it for 30hs under the 30-40%. After stopping supplying of ammonia for 4hs and keep the temperature, cool it to 180deg.C-200deg.C and out the oven. The improved method has certain practicability and reliability on the wearing capability of the rotating shuttle. It reduces the technology of hard chromium plating, which improves its economic and social benefits.

Description

The processing method of the wear-resisting rotating shuttle of sewing machine

Technical field: the present invention relates to sewing machine, particularly relate to the processing method of the wear-resisting rotating shuttle of heart part sewing machine of sewing machine.

Technical background: rotating shuttle is the heart parts of sewing machine, also is the consumable accessory of constantly changing, and is more than more than one hundred million covers in its annual requirement of China.Present existing traditional diamond-making technique (mainly) is: (raw material) forging → roughing → carbo-nitriding (860 ℃ of control temperature) → fine finishining → hard chrome plating → facing-up.Owing to adopt the carbo-nitriding heat treatment process, its temperature height, distortion is big, allowance for finish is corresponding also bigger, thereby destroyed carbo-nitriding surface texture (being almost carbide), not only reduced the abrasion-resistance of rotating shuttle, and increased running noise, cause the broken string frequency to increase, increase use cost.Therefore, improving the rotating shuttle abrasion-resistance, improve service life, reduce cost, is Ji art Ren person Very problem to be solved.

Summary of the invention: purpose of the present invention is exactly the processing method that the wear-resisting rotating shuttle of a kind of sewing machine will be provided.It can solve the problem that present rotating shuttle processing method exists well, the object of the present invention is achieved like this, the processing method of the wear-resisting rotating shuttle of sewing machine, it is characterized in that: rotating shuttle adopts 38 CrMoAl materials after forging, roughing, fine finishining, put into heat-treatment furnace, adopt isothermal heat of adsorption nitriding, temperature is controlled between 480 ℃-520 ℃, under the situation of setting ammonia dissociation rate 18-25%, be incubated 15 hours, continuation is under the situation of setting ammonia dissociation rate 30-40%, be incubated 30 hours, stop to cool to 180 ℃-200 ℃ with the furnace and coming out of the stove for after the ammonia insulation in 4 hours.The present invention at first changes the heat treatment carbo-nitriding into isothermal heat of adsorption nitriding, and temperature is controlled at 480 ℃-520 ℃ (can avoid white layer fragility, distortion little); Next is placed into fine finishining before the heat treatment, and nitration case is not destroyed; Secondly in order to improve factor such as isothermal heat of adsorption nitriding effect, raw material 20Cr is changed into typical nitride material 38CrMoAl (or common nitride material such as 20CrMnTi, 20CrMnMo) again.The present invention begins to heat treatment and improvement thick, method for fine finishing from changing raw material by theory analysis and repetition test.Product of being produced and old-fashioned production method product processed, under with 8000 rev/mins of uniform velocity, equal good lubricating condition, their wear extent of test after 72 hours turns round, learn that former processing method average abrasion amount is 0.018 millimeter, processing method average abrasion amount after the improvement is 0.005 millimeter, and the abrasive resistance of rotating shuttle is brought up to more than 3 times.The present invention has higher surface hardness and wearability; Crisp firmly and not, the good toughness in surface, there are higher seizure resistance, running noise little; Higher antifatigue Strong degree and thermohardening characteristics such as (hardness are constant under 500-600 ℃ of situation) is arranged.Comprehensive above advantage, the processing method after the improvement has certain practicality and reliability to the raising of the abrasive resistance of rotating shuttle, and has reduced Hard Chromium Plating Technology, thereby has improved the economic benefit of self greatly, and social benefit.

Be that processing method (mainly) after improving is below;

(38CrMoAl) forging → roughing → fine finishining → isothermal heat of adsorption nitriding (480 ℃-520 ℃) → facing-up.

Description of drawings: Fig. 1 is that material of the present invention is the isothermal heat of adsorption nitriding process curve figure (infiltration layer 0.25-0.35 millimeter) of 38CrMoAl steel; In the drawings, ℃ expression temperature, h represents the time.

The specific embodiment: the processing method of the wear-resisting rotating shuttle of sewing machine of the present invention, it is characterized in that: rotating shuttle adopts 38 CrMoAl materials after forging, roughing, fine finishining, put into heat-treatment furnace, adopt isothermal heat of adsorption nitriding, temperature is controlled at 520 ℃, under the situation of setting ammonia dissociation rate 18-25%, is incubated 15 hours, continuation is under the situation of setting ammonia dissociation rate 30-40%, be incubated 30 hours, stop to cool to 180 ℃-200 ℃ with the furnace and coming out of the stove for after the ammonia insulation in 4 hours.The present invention at first changes the heat treatment carbo-nitriding into isothermal heat of adsorption nitriding, and temperature is controlled at 520 ℃ (can avoid white layer fragility, distortion little); Next is placed into fine finishining before the heat treatment, and nitration case is not destroyed; Secondly in order to improve factor such as isothermal heat of adsorption nitriding effect, raw material 20Cr is changed into typical nitride material 38CrMoAl (or common nitride material such as 20CrMnTi, 20CrMnMo) again.During concrete enforcement, new raw material 38CrMoAl is forged, require to carry out roughing, stay seldom surplus to carry out fine finishining according to drawing, product after the processing carries out isothermal heat of adsorption nitriding, temperature is controlled at 520 ℃, under the situation of setting ammonia dissociation rate 18-25%, is incubated 15 hours, continuation is under the situation of setting ammonia dissociation rate 30-40%, be incubated 30 hours, stop to cool to 180 ℃-200 ℃ with the furnace and coming out of the stove for after the ammonia insulation in 4 hours.

Claims

1. the processing method of the wear-resisting rotating shuttle of sewing machine, it is characterized in that: rotating shuttle adopts the 38CrMoAl material after forging, roughing, fine finishining, put into heat-treatment furnace, adopt isothermal heat of adsorption nitriding, temperature is controlled at 520 ℃, under the situation of setting ammonia dissociation rate 18-25%, is incubated 15 hours, continuation is under the situation of setting ammonia dissociation rate 30-40%, be incubated 30 hours, stop to cool to 180 ℃-200 ℃ with the furnace and coming out of the stove for after the ammonia insulation in 4 hours.