Identify the authenticity of common spare parts for agricultural machinery

1. Threaded part

The appearance of qualified products should be smooth and free of rust, no defects, continuous thread, no burrs, no cracks. The test piece and the standard accessory are screwed together, and should be able to be screwed to the terminal, and there is no stuck phenomenon during the screwing process; after the screwing, the connecting piece should be free from sloshing and impact sound, if the threaded piece is rusted, Defects such as cracks and burrs, if the connector is shaken after screwing, it will be inferior,

2. Tire

Both sides of the qualified tire tires have trademarks, models, specifications, layers and cord materials, etc., and are clear and eye-catching, and some are also printed with the production number and the cover with inspection; the inner tube surface should be smooth and bright, hands The grip is elastic. If the surface of the tire is incomplete or blurred, the inner tube is dull, the carcass is thin and the thickness is uneven, and the hand is inelastic, which is a defective product.

3. gear

Qualified gear packaging should be intact, the tooth surface should be smooth, no cutting marks, no burrs, and coated with anti-rust oil (or waxing). The gear side is generally coded; the working surface of the broken gear with the steel saw blade should be No scratches or only thin scratches. If the gear surface has burrs, cuts, rust, and there are scraps and scratches (insufficiency in hardness) at the time of the frustration, the quality is poor.

4, bearing

Qualified ball bearings are made of high-quality bearing steel. The inner and outer rings and cages should be bright as a mirror after wiping off the anti-rust oil. The hand should be smooth and delicate like glass; the outer ring end should be engraved with the code name and origin. And the date of the factory and other signs, and clear and conspicuous; rivet riveting between the cage should be uniform, the rivet head is not biased. Support the inner ring by hand, the outer ring should be rotated by the other hand, the outer ring should be able to rotate quickly and freely, and then gradually stop; mark on the outer ring, the stop position should be different each time the stop is stopped; Live the inner and outer rings so that they move relative to each other in the radial and axial directions. There should be no sense of play. Larger bearings can feel the gap, but there should be no metal impact. After completing the above inspection and deciding to purchase, the hardness test can be carried out (it is agreed with the merchant first, if the hardness does not meet the requirements, it will be returned): the outer ring and the inner ring of the bearing or the shovel Produces a "giggle" with no swarf, no scratches or only inconspicuous fine marks. If the bearing mark is ambiguous, the appearance is dull, there is a gap in the sway, the outer ring is screwed at the same position, there are scraps or scratches on the scratch, and the rust stain on the cage, indicating that the bearing quality is unqualified.

5. Oil seal

The surface of the qualified rubber oil seal should be smooth and smooth without deformation and deformation. The side has the code, specification and manufacturer's mark. The shape and thickness of the cutting edge should be the same on the whole circumference of the oil seal. When the fitting is tested, the cutting edge is on the journal. It should be tightly fitted; the shape of the oil seal with the skeleton should be straight, the end face is round, and it can be attached to the surface of the flat glass without deflection; the outer edge of the non-frame oil seal should be straight, the hand can be deformed, and the original shape can be restored after loosening the hand; The oil seal spring of the spring should be free from rust and deformation. The spring is tightly buckled in the lip without looseness. If the oil seal has irregular shape, defect, weakened elasticity, uneven thickness of the lip, spring corrosion and other phenomena, the quality is unqualified.

6. V belt

The qualified V-belt has a smooth surface and the joints are seamlessly bonded. There are clear marks on the outer circumference, such as trademarks, specifications, and manufacturer names. The length of the V-belts of the same model should be the same. If the appearance of the V-belt is rough, the rubber joint is not flat or open, the edge of the cord is exposed, and there is no marking or marking, and the length of each V-belt is different, indicating that it is a fake.

7. V pulley

The surface of the qualified V-belt has no air holes and cracks, and the groove is smooth. When the V-belt buckles with the groove, the V-belt is slightly higher than the notch and the bottom of the V-belt is not contacted by the groove bottom. If the groove and other defects are found, the groove surface If the shape is not matched with the qualified V-belt, it is inferior.

8. Filter

The filter gap of the qualified filter paper is between 0.04-0.08mm, the filter paper is arranged in order, the quality is hard and firm, and it is not deformed after oil absorption; the material of the central tube of the filter element is high-quality steel, the mesh size on the top is moderate, and the medium is obtained. Oil pressure, not easy to deform. If the filter paper is soft, the loading and unloading is disordered, the mesh size is different, and the filter paper is not firmly connected to the upper and lower trays, indicating that the quality is not good.

9. Chain

The commodity chain is coated with anti-rust oil and is accompanied by a certificate; the connecting plate is smooth, free of burrs and black, and the rivets are evenly distributed at both ends of the pin, and some of the connecting plates are printed with grades. Place the chain on the glass plate (pin axis is vertical), use two fingers to clamp the middle of the chain and slowly lift it up. When the two ends of the chain start to leave the glass surface, stop lifting. At this time, the middle part of the chain should be below 10mm from the glass plate. Otherwise the gap is too large.

10. Piston ring

The surface of the qualified parts is fine and smooth, no manufacturing defects, no distortion and good elasticity; when the corners of the piston ring are cut by the broken line of the steel strip, the corners of the ring are not damaged. If the piston ring is inelastic, the surface is rough, and the corners are damaged, the piston ring is of poor quality. (香萱)