重庆磊明自动化设备有限公司

首页  >>  News  >>  Technology

Assembly technical requirements

作者:    时间:2019-08-30    浏览次数:42

分享到:

1. Basic requirements

1.1 Assembly must be carried out in accordance with the design, process requirements and this and related standards.

1.2 The assembly environment must be clean. The assembly environment temperature, humidity, dust prevention, and lighting protection of high-precision products must comply with relevant regulations.

1.3 All parts (including outsourced and outsourced parts) must have an inspection certificate to be assembled.

1.4 Parts must be cleaned and cleaned prior to assembly, without burrs, flash, scale, rust, chips, sand, dust and oil, and should meet the appropriate cleanliness requirements.

1.5 Parts must not be bumped, scratched or rusted during assembly.

1.6 Parts that are not dry may not be assembled.

1.7 Relatively moving parts, lubricating oil (fat) should be added between the contact surfaces during assembly.

1.8 Each zero, the relative position of the components after assembly should be accurate.

1.9 In principle, it is not allowed to operate on the machine during the assembly. Special parts must be taken when operating on the machine.

Special measures, use the protective cover to cover the part to be stepped on, the operator must wear flat-bottomed shoes to prevent damage to the paint film, battery and non-metal and other low-intensity parts are strictly prohibited to step on.

2, the requirements of the connection method

2.1 Screw and bolt connection

2.1.1

When tightening screws, bolts and nuts, it is strictly forbidden to strike or use improper screwdrivers and wrenches. After tightening, the screw slots, nuts, screws and bolt heads must not be damaged.

2.1.2

Fasteners with specified tightening torque requirements shall be tightened with a torque wrench according to the specified tightening torque. For bolts that do not specify tightening torque, the tightening torque can be referred to the provisions of Appendix 1.

2.1.3

When the same part is fastened with multiple screws or bolts, each screw (bolt) should be tightened clockwise, staggered, and symmetrically. If there is a positioning pin, start with the screw or bolt near the positioning pin.

2.1.4

When using a double nut, install a thin nut and then install a thick nut.

2.1.5

After the screws, bolts and nuts are tightened, the screws and bolts should generally expose the nut 1-2 pitches.

2.1.6

After the screws, bolts and nuts are tightened, the bearing surface should be attached to the fastened parts.

2.2 pin connection

2.2.1The end face of the locating pin should generally be slightly higher than the surface of the part. After the taper pin with the screw tail is loaded into the relevant part, the large end should sink into the hole.

2.2.2After the cotter pin is loaded into the relevant part, the tail should be separated by 60° to 90°.

2.2.3 When the important tapered pin is assembled, it should be inspected with the hole. The contact length should not be less than 60% of the working length and should be distributed on both sides of the joint.

2.3 key connection

2.3.1The sides of the keyway of the flat key and the fixed key should be evenly contacted, and there should be no gap between the mating surfaces.

2.3.2After the clearance of the key (or spline) is assembled, there shall be no unevenness in the movement of the relatively moving parts along the axial direction.

2.2.3After the hook key and the 锲 key are assembled, the contact area shall not be less than 70% of the working area, and the non-contact part shall not be concentrated in one place; the length of the exposed part shall be 10%~15% of the length of the inclined surface.

2.4. Riveting

2.4.1Riveted materials and sizes must meet design requirements. The processing of the rivet holes shall comply with the relevant standards.

2.4.2The surface of the riveted part shall not be damaged during riveting, nor shall the surface of the riveted part be deformed.

2.4.3Except for special requirements, there should be no looseness after riveting, the head of the rivet

Must be in intimate contact with the riveted part and should be smooth and round.

2.5 Assembly of rolling bearings

2.5.1The bearings must be clean before assembly.

2.5.2For grease-lubricated bearings, approximately one-half of the cavity should be filled with the specified grease after assembly.

2.5.3When assembling by press-in method, apply a special press or pad or sleeve on the interference fit ring, and do not transmit pressure or striking force through the rolling elements and the cage.

2.5.4The inner end of the bearing inner ring should generally be close to the shoulder. The tapered roller bearing and the radial thrust bearing should be no more than 0.05mm, and the other bearings should be no more than 0.1mm.

2.5.5After the outer ring of the bearing is assembled, the contact between the bearing end of the positioning end and the washer or the outer ring should be uniform.

2.5.6When assembling a detachable bearing, it must be installed according to the inner and outer rings and the alignment mark, and must not be reversed or mixed with other inner and outer rings of the bearing.

2.5.7Bearings with adjustable head assembly shall be assembled with the numbered end outward for identification.

2.5.8For bearings with eccentric sleeves, the tightening direction of the eccentric sleeve should be consistent with the direction of rotation of the shaft during assembly.

2.5.9After the rolling bearing is installed, the rotation of the relative moving parts should be flexible and light, and there must be no jamming. .

2.5.10The axial clearance of single row tapered roller bearings, thrust angular contact bearings and double direction thrust ball bearings shall comply with the drawings and technical requirements during assembly.

2.5.11 The bearing outer ring and the open bearing housing and the semi-circular hole of the bearing cap should be in good contact. When the coloring method is used for inspection, it should be evenly contacted with the bearing seat within 120° symmetrical with the center line; Uniform contact within 90° of the centerline. Within the above range, when inspected with a feeler gauge of 0.03 mm, it shall not be inserted into one third of the width of the outer ring.

2.5.12 There are adjustable radial bearings on both sides of the shaft, and the axial displacement is limited by the end caps. Only one end bearing should be close to the end cap, and the other end must have axial clearance. C=α△tl+0.15(L: center distance between two axes (mm) α: coefficient of linear expansion of the shaft △t: difference between the highest working temperature of the shaft and the ambient temperature (°C) 0.15: the remaining gap after the thermal expansion of the shaft (mm))

3 Assembly of sprocket chain

3.1 The cooperation between the sprocket and the shaft must meet the design requirements.

3.2 The geometric center plane of the tooth sprocket and the driven sprocket shall coincide, and the offset shall not exceed the design requirements. If the design is not specified, it should generally be less than or equal to two thousandths of the center distance of the two rounds.

3.3 When the chain is engaged with the sprocket, the working edge must be tightened to ensure a smooth meshing.

3.4 The sag of the non-working side of the chain shall meet the design requirements. If the design is not specified, it should be adjusted from 1% to 2% of the center distance of the two sprockets.

4 belt and pulley assembly

4.1 The position of the symmetric center plane of the pulley wheel groove of the same circuit is not more than 0.3% of the center distance of the pulley when the center distance is less than 1.2m; and not more than 0.5% of the center distance of the pulley when it is greater than or equal to 1.2m.

4.2 The tension of each transmission belt should meet the requirements of the Futian “Gu Shen 2” system inspection card.

5 Assembly of hydraulic system

5.1 The piping of the hydraulic system must be rusted and cleaned before assembly. Pay attention to dust and rust during assembly and storage.

5.2 All pipes shall be free of dents, wrinkles, flattening, rupture, etc. The bends of the pipeline shall be smooth and shall not be twisted.

5.3 The piping should be arranged neatly and facilitate the adjustment and maintenance of the hydraulic system.

5.4 The hydraulic fluid injected into the hydraulic system shall comply with the design and process requirements.

5.5 After assembly, the hydraulic lines and components shall not have oil leakage. To prevent leakage, seal packing and sealant may be used during assembly, but should be prevented from entering the system.

5.6 The hydraulic control system and steering system should be flexible and free of jams.

5.7 After the hydraulic system is installed, the operation test shall be carried out in accordance with relevant standards.

5.8 Other requirements regarding hydraulic systems and hydraulic components are to comply with the requirements of GB/T3766.

6. Assembly of electrical systems

6.1 Electrical components shall be tested and inspected prior to assembly, and unqualified shall not be assembled.

6.2 The digital and signal displayed by the meter and indicator should be clear and accurate, and the switch works reliably.

6.3 Wiring and connection shall be carried out in strict accordance with the requirements of the electrical assembly drawings.

6.4 The insulation of all wires must be intact, and the thin copper wire at the wire stripping must be tightened and tinned when needed.

6.5 Solder joints must be firm and free of desolder or weak solder joints. Solder joints should be smooth and uniform.

7 balance

7.1 Threshing drum, stepless speed change and belt with speed exceeding 400r/min and weight greater than 5kg

The wheel should be statically balanced or dynamically balanced and the balance accuracy should not be lower than G6.3.

7.2 The unbalanced mass of the rotating parts can be corrected by the following methods:

7.2.1

Add the quality (weight) with repair welding, threaded connection, etc.

7.2.2

Use a drill pin to remove mass (de-weight).

7.2.3

Change the number and position of the balance blocks.

7.3 When calibrating with the added quality method, it must be fixed firmly to prevent loosening or flying out during work.

7.4 When calibrating by means of mass removal, care must be taken not to affect the stiffness, strength and appearance of the part.

7.5 For combined rotary bodies, the parts must not be moved or exchanged arbitrarily after being balanced.

8

Each adjustment mechanism should ensure convenient operation and flexible and reliable adjustment. The adjustment range of each component should be able to reach the specified limit position.

9 Each operating mechanism should ensure that the operation is light and flexible, and the tightness is moderate. All control parts that require automatic return should automatically return to their original position after the operating force is removed.

10 final assembly

10.1 In the final assembly, the random attachments should also be tested and the design requirements must be guaranteed.

10.2 The rigid header should be consistent with the ground clearance, and the difference should be no more than 15mm.

10.3 Travel brakes and parking brakes should ensure reliable harvesting of the harvester.

10.4 The engine start should be smooth and stable, and the flameout should be completely reliable. When the ambient temperature is not lower than -50C, it should start smoothly.

10.5 All machine marks shall be affixed to the designated parts according to the design requirements, and shall not be skewed or uneven.

10.6 The test machine shall ensure that the main engine has an operation record of more than 2 hours before leaving the factory.

023-88119758