Cutting technology for fine parts machining and technical requirements for bearings

The wires often used in fine parts machining are molybdenum wire, tungsten wire, brass wire and cored wire, and so on.

Wire cutting:

Slow walking wire processing machine tungsten wire tensile resistance, the price is relatively expensive, generally used for a lot of narrow seam finishing. Brass wire suitable for slow processing, processing surface roughness and flatness good, etching chip attachment less, but poor tensile strength, loss of large, in slow one-way walking wire in a wide range of applications. Molybdenum wire tensile strength is good, mainly used in fast walking wire processing, general mechanical processing enterprises in China mostly choose the molybdenum wire for wire.

Wire cutting:

Slow walking wire processing in wire cutting there are 3 types, different types of precision is also different, respectively: fast walking wire, in the walking wire and slow walking wire; general fast walking wire precision can reach +/-0.02mm, surface roughness can reach Ra3.2; in the walking wire precision can reach +-/0.01mm, surface roughness can reach ≤ Ra3.2; slow walking wire precision can reach +/-0.005mm. The precision of slow walking wire can reach +/-0.005mm and the surface roughness can reach Ra0.8, therefore, the slow walking wire is higher than the other two kinds in precision and quality. Wire cutting in the EDM piercing, forming processing on the basis of the development. It not only makes the application of EDM has been developed, and some aspects have replaced the EDM piercing, forming processing. Nowadays, wire-cutting machine tools have accounted for most of the EDM machine tools, and play a great role in the detailed parts processing.

Detailed parts processing bearing technology requirements:

First, assembly of rolling bearings is allowed to use oil heating for hot mounting, the temperature of the oil can not exceed 100 ℃.

Second, rolling bearings should be flexible and smooth after mounted and rotated by hand.

Third, the outer ring of the bearing and the half circle hole of the open bearing seat and bearing cover should be in good contact, when checking with colouring, it should be uniformly contacted with the bearing seat in the range symmetrical to 120° of the centre line, and with the bearing cover in the range symmetrical to 90° of the centre line. In the above range with a ruler check, 0.03mm of the ruler can not be plugged into the outer ring width of 1/3.

Fourth, the combination of upper and lower axial tile surface should be close to and, with 0.05mm plug ruler check not into.

Fifth, spherical bearings of the bearing body and bearing seat should be uniform contact, check with the colouring method, the contact should not be less than 70%.

Six, with positioning pins to fix the axial tile, should be in the determination of the tile mouth surface and end surface and the related bearing hole opening and closing surface and end of the bread hold flush state drilling hinging, with pins. The pin should not be loosened after it is driven in.

Seven, alloy bearing lining surface into yellow is not allowed to use, in the specified contact angle is not allowed to have the nucleus phenomenon, in the contact angle outside the nucleus area can not be greater than 10% of the total area of non-contact area.

Eight, bearing outer ring and open bearing seat and bearing cover half-round hole is not allowed to have stuck phenomenon.

Nine, bearing outer ring assembly and positioning end bearing cover end face should be contact uniform.