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IC$25.060.20
Machinery Industry Standard of the People's Republic of China
JBT9941-1999
Combination Clamp
Published on 1999-05-20
Assembly Complexity Level
2000-01-01 Implementation
National Bureau of Machinery Industry
JBFT99411999
This standard is a revision of JB/7.19983 "Combination Clamp Assembly Complexity Level". The original version was formulated based on the structural characteristics of combination fixtures and many years of production experience. Its technical content can still meet the current scientific level and meet the needs of production and use. This standard is consistent with the technical content of JB/Z19983, and has only been re-edited according to relevant regulations. This standard replaces JB/Z199-83 from the date of implementation. This standard is proposed by the National Technical Committee for Standardization of Cutting Machine Tools, and this standard is under the jurisdiction of the Combined Tools Branch of the National Technical Committee for Standardization of Cutting Machine Tools. The drafting units of this standard are: Tianjin Combined Tools Research Institute, Kangzhou Machinery Standard Combined Tools Assembly Station. The main authors of this standard are: Tai Aokun, Liu Derong, 1 Scope
Machinery Industry Standard of the People's Republic of China
Combination Tools
Assembly Complexity Level
This standard specifies the classification basis, method and classification standard for the complexity level of combined tools JB/T9941—1999
Replacement JBV99-83
This standard is applicable to various types of tools assembled with 12mm combined tools components, to verify the assembly classification and assembly support technology, and can be used as the basis for assembly stations (rooms) to formulate assembly charging standards for combined tools, and the classification basis for each assembly complexity level
21 "Complexity Level of Assembly of a Group of Tools" The degree of complexity, including the overall work of drawing, determining the assembly plan, assembling and sizing, and performing the corresponding data calculations.
2.2 The standard specifies that the assembly complexity gradient of the fixture is in levels. In general, each level in the standard is specified as the amount of work equivalent to the assembly completed in 1.5 hours. 3 Method for grading the level of assembly complexity
3.1 The assembly complexity of a combination fixture is determined by the basic assembly level and the additional component level. 3.2 The basic assembly level is determined by some technical parameters of the fixture, and is divided into drilling fixtures, milling fixtures, grinding fixtures, lathe fixtures and chain hole fixtures according to the type of fixture. In addition to the additional component level, the other types of fixtures are divided into fixed levels. Position, flame hood, structural form of the fixture, workpiece size, accuracy requirements, components used and special instructions, etc. Each factor or number only plays a role in the tool classification. 3.3 For fixtures that do not include the above-mentioned type 1, the grade can be determined by referring to the classification regulations for fixtures of similar structures. 3.4 The level of miscellaneous grades of other fixtures is the lowest level, and there is no requirement for higher levels. 35 Sets of fixtures encounter special circumstances that are beyond the scope of this regulation, such as the workpiece size is particularly large, the user has special requirements, the clamp is adjusted on the machine tool, etc., and the situation can be accommodated after consultation with the user. 4 General fixture miscellaneous grade classification standards
4.1- Determination of the basic requirements of general fixtures
4.1.1 The basic level of the drilling machine fixture is determined by the number of station templates required for the wave assembly. The specific regulations are shown in Table 1.
Borrowing level
Drilling template number
4.1.2 The basic level of the planing and flattening support is determined by the maximum size of the workpiece related to the fixture. The specific regulations are shown in Table 2. Table 2
>150-300
Approved by Guohao Machinery Industry Bureau on 19-05-10
>340~45
>n00-750
>750-900
>900~1050
Implemented on 2000-01-01
JB/T 9941—1999
4.1.3 The basic level of the lathe is determined by the required rotary diameter, and the specific level is shown in Table 1. Table 3bZxz.net
Basic level
4.2 Generally speaking, the rigid conditions for the specific level
4.2. The specific level
>240-360
4.2.1.1 When positioning with two holes or with a hole with a distance requirement from the positioning surface, add one level, 4.2.1.2 When positioning with a large hole or an external stop assembled from several complete parts, add one level. 4.2.1.3 When using "positioning", add one level,
4.2.1.4 The position size of the positioning element needs to be adjusted, and the error is less than 0.03mm, add one level. 5
360~480
4.2.1.5 For tools with more than one position or multiple workpieces, if the workpiece needs to be changed after assembly, the positioning point or the tightening structure should be changed.
4.2.1.6 *Bent plate type", add one level when the tail surface and the outer surface are positioned, 4.2.2 Structural aspects
4.2.21 The fire tool needs to be assembled at one angle, add one level. If it is not necessary to calculate the size and assemble the mountain angle, add two levels, 4.2.2.2 The fire tool needs to be assembled at two angles, add three levels. 4.2.2.3 It has two or more degrees and needs to change the wire or adjust the size by one level, add four levels, 4.2.2.4 It has two or more degrees and needs to calculate the angle and adjust the size or calculate the tool, five to six levels.
4.2.2.5 Double guide drilling, add one level
Mobile drilling, add two levels.
4.2.2.7 Cover plate type drilling fire tool, its size When the size is not more than 300mm, add one level; when it is more than 300mm, add two levels. 4.2.2.8 Rotary drill: when the size is not more than 200mm, add one level; when it is more than 200mm, add two levels. 4.2.2.9 Rotary or movable clamps can add one level. 4.2.2.10 The parts that must be assembled with drill bits and plates and other parts for indexing can be increased according to the number of indexing times. 4.2.2.11 The parts are processed by multi-hole stations, distributed on a cross section, and the lower surface is aligned with the positioning reference, and the clamps can be assembled in detail. When the number of plates to be assembled reaches three, reduce one level. 4.2.2.12. Due to the structural complexity or poor rigidity of the workpiece, in addition to the positive positioning cumulative fulcrum, the number of adjustable fulcrums and optical tightening joints that must be added in more than three places can be increased by one level. 4. 2. 3 Size
4z.3.1 For the length of the workpiece related to the drill, if it is greater than 4M-600mm, add a grade; if it is greater than 600.800mm, add a grade; if it is greater than 800-1000m, add a grade; if it is greater than 1000-1200mm, add a grade 4. 4.2.3.2 For the workpieces of the size listed in 4.2.3.1, when the various types of optical tools need to be assembled at an angle, add a grade 4. 4.2.3.3 For the height of the workpiece related to the drill, if it is greater than 300~400mm, add a grade; if it is greater than 400-500m, add a grade; if it is greater than 50-6mm, add a grade 5. 4.1.3.4 For the diameter of the drill plate used in the drill, if it is greater than or equal to 2mm, and the number of drill templates is not more than five, add a grade 1; if it is more than five, add a grade 2. 、
JB/T9941-1999
4.2.3.5 When the half height of the turning tool is greater than 180-240mm, add one level; when it is greater than 240-300mm, add two levels. 4.2.3. When the size of the lower part is smaller than 12mm, the components are not compatible with each other, which will cause one to two complicated tool assembly. 4.2,4 Degrees
4.2.4.1 When the width tolerance of the hole in the drawing is within 10.05mm, add one level. 4.1.4.2 When the drawing requires that the drilled hole is not more than 1/100 of the base surface or the hole level, add one level; when the pin hole is not more than 0.1/100mm and the base surface or the filling verticality is not more than 0.1/100mm, add one level; when the coaxiality of the two holes is not more than 0.03mm, add one level; 4.2.4.3 When the drawing requires the angle tolerance is not more than 5, add one level. 4.2.4.4 When the drawing requires that the flatness between the surface and the reference surface is not greater than 0.02/100mm, it is a level. 4.2.4.5 When the drawing requires that the flatness between the hole and the surface is not greater than 0.05/100mm, it is a level. When the verticality between the hole and the base surface is not greater than 0.03100mm, it is a level. When the distance between the moving hole and the base surface is not greater than ±0.03mm, it is a level. 5 The combination of the support hole assembly complexity level is the body regulation 5! The combination of the barrier hole optical fixture refers to the fixture that needs to be assembled with double guides and uses the hall rod for work. For the assembly of the double recording, only the assembly positioning and tightening and the alignment fixture are not within the scope of this regulation. Its complexity level can be determined by signing the fixture of similar structure 5.2 The assembly of the combination of the support hole is more complicated. The general complex level of the fixture cannot meet the requirements. For this need, please refer to the regulations. It is now stipulated that the level of the combined boring fixture is equivalent to the level of complexity of the general fire tool assembly, which is used as the basis for the classification of the combined boring fixture. 5.1 The classification method of the combined boring fixture is still determined by the basic assembly level and the additional condition level. 5.4 The basic grade of the combination hole is determined by the number of staggered hole supports, and the standard is shown in Table 4. Table 1
Basic card
Courtesy
5.5 Additional conditions for the grading of combination chain holes 3-4
5.5.! The length is greater than 400-800mm or the height and width are greater than 100~600mm, which is the first grade. When the length is greater than 800mm or the height and width are greater than 600mm, add two grades. 5.5.2 When the guide hole diameter of the pressure support is 7Umm or 90mm, it is the first grade. 5.5.3 When the H surface of the main fixed part is straight with the processed surface, it is the first grade. 5.5.4 For positioning of the tail, long cylinder, V-shaped guide rail, and double nipple, add one level. 5.5.5 For straight holes with pins, if there is a positioning accuracy requirement, the hole should not exceed one level, and more than two pairs of holes should be added at two levels. 5.5.6 For mobile continuous holes, add one level.
5.5:7 Use a hanging plate type hole fixture, and add one level for each hanging plate installed. 5.5. If there are two angles, add two levels. 5.5.9 If there are two angles, add four levels.
5.5.10 If rotary or actuated compensation holes are used, add one level. 5.5.11 The distribution of holes is complex or the precision is high, and the assembly is labor-intensive. In such special cases, one rate or two levels can be cut.
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