This standard specifies the technical requirements for the design and manufacturing of light industrial mechanical cutting parts. This standard applies to the design and manufacturing of light industrial mechanical cutting parts (hereinafter referred to as "processing parts"). QB/T 1588.2-1992 General Technical Requirements for Light Industrial Mechanical Cutting Parts QB/T1588.2-1992 Standard download decompression password: www.bzxz.net

Light Industry Industry Standard of the People's Republic of China
Light Industry Machinery
General Technical Conditions for Cutting Machined Parts
1 Subject Content and Scope of Application
This standard specifies the technical requirements for cutting machined parts of light industry machinery in the design and manufacturing process. This standard applies to the design and manufacture of cutting machined parts of light industry machinery (hereinafter referred to as "machined parts"). 2 Referenced Standards
GB/T197 Tolerances and fits of ordinary threads (diameter 1 to 355 mm) GB/T 1144
GB/T 1184
GB/T 1804
Dimensions, tolerances and inspections of rectangular splines
Form and position tolerances Tolerances for unspecified tolerances Tolerances and fits Limit deviations of dimensions for unspecified tolerances GB/T 5796. 4
GB/T 10089
GB/T10095
GB/T10096
GB11335
Trapezoidal thread tolerance
Cylindrical worm and worm wheel accuracy
Involute cylindrical gear accuracy
Rack accuracy
Limit deviation of unindicated tolerance angle
GB/T11365
Accuracy of bevel and hypoid gears
Tooth thickness deviation of cylindrical gears, gear pair sides and gears for machine toolsJB/GQ 1070
JBn 3997
3 Basic requirements
General technical conditions for grey cast iron for machine tools
QB/T 1588.2—-1992
3.1 The machined parts must comply with the product drawings, process documents and relevant standards approved through the prescribed procedures. 3.2 The machined surface of the machined parts shall not have defects such as bumps, scratches and rust. 3.3 Unless otherwise specified, the machined parts shall not have sharp shuttles, sharp corners and burrs. 3.3.1 When the chamfer size is not indicated in the drawing, the chamfer shall be in accordance with the provisions of Figure 1 and Table 1. CX45'
Approved by the Ministry of Light Industry of the People's Republic of China on August 31, 1992Diagram 1
Cx45°
Implemented on April 1, 1993
>5～30
QB/T 1588. 2-—1992
>30～100
>100～250
When the drawing does not indicate the fillet radius, filleting shall be in accordance with the provisions of Figure 2 and Table 2. Figure 2
>4～12
≥10～30
>12～30
>30～80
>30~80
>80～260
Note: 1) The D value is used for filleting of blind holes and outer end faces. The fillet of non-cylindrical surface can refer to this table. 3.4 During the fine processing of heat-treated workpieces, defects such as annealing and overburning shall not be produced. >250500>5001000
>80~140
>140~～200
>260~630>630~1000
>1 000
3.5 For common internal and external threads without tolerance zone code, the tolerance zone shall adopt 6H and 6g specified in GB/T197; for common internal and external threads without surface roughness code, the surface roughness R value shall not be greater than 6.3um. The tolerance of trapezoidal thread shall comply with the provisions of GB/T5796.4. Surface defects such as burrs, black skin and bumps are not allowed on the processed threads. 3.6 The limit deviation of untoleranced angles shall be selected according to the tolerance grade in GB11335 and specified in the corresponding technical documents. 3.7 Limit deviation of untoleranced dimensions
3.7.1 When the limit deviation of the size of the machined part is not specified, a grade not lower than IT14 in GB/T1804 shall be selected. Its limit deviation shall be in accordance with the provisions of Table 3.
Hole size
Shaft size
JS14(js14)
3.7.2 When the chamfer size and fillet radius of important matching machined parts are not specified with limit deviation, they shall not exceed the provisions of Figure 3 and Table 4. Figure 3
C(C),r(rr)
Limit deviation
AC(Ar)
ACt(Ar)
3.8 Unspecified geometric tolerances
QB/T 1588.2—1992
>3～6
>6～30
3.8.1 Unspecified straightness and flatness tolerances shall not be lower than Class B and Class C in Table 1 of GB/T1184, and shall comply with the provisions of Table 5.
Surface roughness R of the measured element Value/μm
0.012~1.600
3.200~~25.000
Tolerance grade of straightness and flatness
3.8.2 The tolerance value of coaxiality without annotation shall not be lower than Grade C in Table 2 of GB/T1184. 3.8.3 The tolerance value of symmetry without annotation (except keyway) shall not be lower than Grade C in Table 2 of GB/T1184. 3.8.4 The tolerance value of symmetry without annotation of keyway shall comply with Grade A in Table 2 of GB/T1184. See Table 6 for specific values. Table 6
Key width h
Symmetry tolerance value
>3～6
>6～10
>10～18
≥18～30
>30～50
>50~100
3.9 For the previous process where the surface roughness requirement is not specified in the technical documents, the surface roughness R. value shall not be greater than that specified in Table 7. Table 7
Processing requirements
Before finishing
Before reaming
Before finishing grinding
Surfaces to be surface hardened, ultrasonically inspected or hydraulically processed in the next process
Main workpiece requirements
4.1 Spindle
Surface roughness R. value
4.1.1 The spindle shall be heat treated. The hardness of the spindle journal that matches the bearing: when using sliding bearings, it should generally not be lower than HRC 52; when using rolling bearings, it should generally not be lower than HRC48; when used as the raceway of rolling bearings, it should generally not be lower than HRC60.4.1.2 The main connection dimensions and parts of the spindle should comply with the provisions of relevant standards, and the fillets of the shoulders on the spindle should have a smooth transition. 4.1.3 The coaxiality of the center hole axis to the axis of the journal should ensure the requirements of the product accuracy standard and leave a reserve. 4.1.4 There should be no obvious ripples on the spindle journal, center hole and center surface. 4.2 Gear
4.2.1 The accuracy of the involute cylindrical gear should comply with the provisions of GB/T10095, and its accuracy grade and tooth surface roughness R. value are recommended to be selected according to Table 8.
Gear form
Spur gear
Helical gear
Spur gear
Helical gear
Spur gear
Helical gear
Spur gear
Helical gear
Circumferential speed
QB/T1588.2—1992
Accuracy grade
Note: Gear accuracy grade refers to the main tolerance group among the three tolerance groups of gear accuracy. Non-main tolerance groups are allowed to be one level lower. 4.2.2 The tooth thickness deviation of the gear should be selected according to the transmission requirements. Refer to the provisions of JB/GQ1070. Tooth surface roughness R. value
The tooth end of the sliding gear should be rounded. Rectangular spline holes with matching requirements should comply with the provisions of GB/T1144. 4.2.3
4.2.4 The accuracy of bevel gears and hypoid gears shall comply with the provisions of GB/T11365. 4.2.5 The accuracy of racks shall comply with the provisions of GB/T10096. 4.3 Worm gear pairs
The accuracy of cylindrical worms and worm wheels shall comply with the provisions of GB/T10089. The accuracy grade and tooth surface roughness R. value are recommended to be selected according to Table 9.
Accuracy grade
Worm and worm wheel tooth surface roughness R. value
4.4 Guide surface and mating surface
Not less than 7. 5
Worm wheel circumferential speed/(m/s）
Not less than 3
4.4.1 The machining accuracy of the guide surface shall ensure the requirements of the product accuracy standard and leave a reserve. 4.4.2
Not less than 1.5
When the mating surfaces of the two mating parts are machined by mechanical processing, the contact should be even and the contact area should not be less than the requirements of Table 10. Table 10
Sliding (rolling) guide rail
Over the entire length
Over the entire width
Over the entire length
Transfer guide rail
Over the entire width
Note: ① Only when the contact in width reaches the specified index can the length calculation be made. ②The insert strip is tested according to the contact index of the matching guide rail. ③The 1 in Table 10 refers to ordinary light machine products [refers to light machine products with higher precision. 18
Specially important fixed joint surface
Over the entire length
Over the entire width
QB/T1588.2-1992
4.4.3 The surface roughness R. value of the guide rail surface and the particularly important fixed joint surface after cutting shall not be greater than that specified in Table 11. Table 11
Cast iron guide railbzxz.net
Steel guide rail
To: 1 in Table 11 refers to ordinary light machinery products: Most refers to light machinery products with higher precision. um
Transfer guide rail and particularly important fixed joint surface 2.00
4.4.4 The flat guide rail surface after cutting shall not have obvious ripples, and the cylindrical guide shoe surface shall not have obvious spiral lines. 4.4.5 The intersection of the machined surface and the unmachined surface of the guide rail shall be chamfered, and the operating surface of the guide rail shall not have cold gaps, slag inclusions and segregation. 4.4.6 The hardness, hardness difference and hardness test method of the cast iron guide surface shall refer to the provisions of JBnm3997. 5 Other requirements
5.1 After each process, the workpiece surface shall be free of chips, water and dirt, and shall be neatly placed on the specified workstations. 5.2 The related parts processed in groups shall be marked after processing. 5.3 The slender shafts without special workstations shall be hung vertically. 5.4 After processing, the fuselage parts shall be placed horizontally and shall not be stacked arbitrarily. 5.5 After processing, the thin-walled circular parts shall be placed vertically. Additional remarks:
This standard was proposed by the Technical Equipment Department of the Ministry of Light Industry. This standard is under the jurisdiction of the National Light Industry Machinery Standardization Center. This standard was drafted by the Hangzhou Light Industry Machinery Design Institute of the Ministry of Light Industry, Jingdezhen Ceramic Machinery Factory of Jiangxi Province, and Hunan Light Industry Machinery Factory.
The main drafters of this standard are Lang Huiqin, Gong Liang, and Liu Runqing. From the date of implementation of this standard, the former Ministry of Light Industry of the People's Republic of China issued the Ministry of Standard QB/T842.5-1982 "General Technical Conditions for Light Industry Machinery Weighing Instruments - Machined Parts" will be invalidated.
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