Three checks should be done during the maintenance

During the maintenance of agricultural machinery, we should pay attention to the "three passes"

the first is disassembly. Before disassembly, agricultural machinery repairmen should try to judge accurately, and try to do less or no disassembly to the greatest extent. Disassembly of parts that do not need disassembly is essentially "damaged" once, adding unnecessary wear and tear. In the essential disassembly, the disassembly method from the last accessory to the main part, from the outside to the inside should be followed, and the disassembly sequence is that the whole machine is first disassembled into an assembly, the assembly is disassembled into components, and then the components are disassembled into parts

during disassembly, use appropriate disassembly tools. If you have special tools, you must use them instead of beating them violently

when disassembling, make preparations for assembly, and remember the original assembly marks of some parts; If there is no mark or the mark is unclear, make a supplementary mark

parts of the same kind that cannot be exchanged, such as valves and bearing bush covers of multi cylinder diesel engines, and parts with marks or labels on the mutual positions of mating parts, such as gears in the gear chamber, connecting rods and connecting rod pads, connecting rod caps, etc., must be stored in categories and groups

second, assembly is off. After repairing or replacing parts, assembly is required. In fact, the resolution of the main force value of the repair quality can almost reach 1 in 400000, which is reflected in the assembly quality. Therefore, the assembly must be careful and assembled according to the technical requirements

1. Assembly shall be carried out in sequence, generally from the inside to the outside. Parts are assembled into components, and components are assembled into assemblies. Avoid missing or wrong installation, and do not drop tools and parts into the machine, leaving hidden dangers of accidents

2. Special tools and equipment should be used as much as possible during assembly. This can not only improve the efficiency, but also ensure the assembly quality when the oil collector of the oil pump is not pressed on the pump body

3. The assembly of the screw set must be tightened evenly in a certain order to ensure that the parts are stressed evenly and prevent oil, water and air leakage caused by warpage. For screws and bolts with certain torque requirements, such as cylinder head screws and nuts, use a torque wrench to tighten them as required

4. When installing the piston pin, piston and other mating parts, the piston should be heated, so as to facilitate installation, and the parts cannot be damaged by violent beating

5. When assembling the moving fitting parts, apply lubricating oil on the fitting surface of the parts to avoid dry friction and loss. Valve rotor pump

6. During assembly, the marked relative parts must be checked to ensure the correct mutual position and movement relationship between them. For example, when assembling the timing gear in the gear chamber of the diesel engine, it is necessary to ensure the correct oil supply and gas distribution time

7. When installing the locking device, iron wire cannot be used to replace the cotter pin. When the iron wire is used to stop, pay attention to the insertion direction of the iron wire to prevent the parts from loosening

8. During the assembly process, the assembly quality should be checked at any time, and problems found should be corrected in time to avoid rework and delay

III. inspection and cleaning

1. Before disassembly, clean the soil, dust, oil stain, etc. outside the agricultural machinery

2. Carry out technical identification and inspection for disassembled and washed parts, judge whether the parts are available according to the standard value and the limit value, and determine whether they need to be repaired or scrapped and replaced with new parts

it largely determines the use of this kind of plastic and rubber

3. Before assembly, clean the spare parts and keep them clean. In particular, www.mechnet com. Cn/"> the plunger coupling, oil outlet valve coupling and needle valve coupling of diesel engine should be kept highly clean.

4. After assembly, it is necessary to carefully check and try the engine again after inspection