JB/T 1128-1999 JB/T 1128-1999 Clearance Thread Gauge JB/T1128-1999 Standard download decompression password: www.bzxz.net

ICS25.060.20
Standard of the Machinery Industry of the People's Republic of China
JB/T1128—1999
Clearance screw thread gauge
1999-05-20 Issued
National Bureau of Machinery Industry
2000-01-01 Implementation
JB/T1128-1999
This standard is revised on the basis of B1128—70 "Clearance screw thread gauge tolerance". The technical content of this standard is consistent with that of JB1128-70, and it has only been re-edited according to relevant regulations. This standard replaces JB1128—70 from the date of implementation. This standard is proposed and managed by the National Technical Committee for Standardization of Measuring Tools and Instruments. The responsible drafting unit of this standard is Chengdu Tool Research Institute. This standard was first issued in 1970.
1 Scope
Standard of the Machinery Industry of the People's Republic of China
Clearance screwthiead gaug
JB/T1128—1999
Replaces JB1128—70
This standard specifies the product classification, tolerance, thread type, technical requirements, marking and packaging of clearance thread gauges. This standard is applicable to the thread gauges used for testing the nominal diameter of 1~120mm, the pitch of 0.2~2mm coarse and fine teeth, which need to form a guaranteed clearance according to GB/T197—1981 "Tolerance and Fit of Ordinary Threads (Diameter 1~355mm)" 2
Cited Standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and the parties using this standard should explore the possibility of using the latest versions of the following standards. Tolerances and fits (diameter 1~355mm)
GB/T 197—1981
Ordinary thread
3 Symbols
The symbols used in this standard and their names or meanings are shown in Table 1. Table 1
are the major diameters of the external thread and the internal thread of the workpiece, respectively; the middle diameters of the external thread and the internal thread of the workpiece, respectively; the minor diameter of the internal thread of the workpiece
Tolerance of major diameter of the external thread of the workpiece
Tolerance of minor diameter of the internal thread of the workpiece
or meaning
are the middle diameter tolerances of the external thread of the workpiece and the internal thread of the workpiece, respectively. In the axial section of the truncated tooth profile, the distance between the top (towards the tooth top side) and the end (towards the tooth bottom side) of the straight part of the tooth side is the distance from the center line of the middle diameter tolerance zone of the through-end or stop-end thread ring gauge to the center line of the middle diameter tolerance zone of the "through-through" thread plug gauge or the "stop-through" thread plug gauge, respectively.
Half-angle tolerance of thread tooth profile
Mid-diameter tolerance of the proofreading thread plug gauge
Pitch tolerance of thread gauge
Mid-diameter tolerance of through-end and stop-end thread plug gaugesMid-diameter tolerance of through-end and stop-end thread ring gaugesTable 1 (End)
Approved by the State Machinery Industry Bureau on May 20, 1999, and implemented on January 1, 2000
4 Product classification
1128—1999
Name or meaning
The distance from the center line of the pitch diameter tolerance zone of the through end thread ring gauge or plug gauge to its wear limitThe distance from the center line of the pitch diameter tolerance zone of the stop end thread ring gauge or plug gauge to its wear limitThe distance from the center line of the pitch diameter tolerance zone of the through end thread plug gauge to the lower deviation of the pitch diameter of the internal thread of the workpieceThe distance from the center line of the pitch diameter tolerance zone of the through end thread ring gauge to the upper deviation of the pitch diameter of the external thread of the workpieceSmooth plug gauge for checking the dimensional tolerance of the minor diameter of the internal thread of the workpieceSmooth ring gauge or caliper gauge for checking the dimensional tolerance of the major diameter of the external thread of the workpieceSmooth ring gauge or caliper gauge for checking the dimensional tolerance of the calibration gauge used for the smooth ring gauge or caliper gaugeThe dimensional tolerance of the calibration gauge used for the smooth ring gauge or caliper gauge is divided into working thread gauge, acceptance thread gauge and calibration thread gauge according to its performance. 4.1
Working thread gauge: refers to the thread gauge used by the operator in the process of manufacturing the workpiece thread. Acceptance thread gauge: refers to the gauge used by the inspection department or user representative when accepting the workpiece thread. Proofing thread gauge: refers to the gauge used when manufacturing the working thread gauge and checking whether the working thread gauge in use is worn.
The names, codes, functions, characteristics and usage rules of thread gauges are shown in Table 2. Table 2
Through end thread plug gauge
No end thread plug gauge
Through end thread ring gauge
No end thread ring gauge
Proofing-through
Thread plug gauge
Proofing-through
Thread plug gauge
The function of checking the internal thread of the workpiece
Middle diameter and major diameterwwW.bzxz.Net
Single for checking the internal thread of the workpiece
The function of checking the external thread of the workpiece||t t||Pitch diameter and minor diameter
Single pitch diameter for checking the external thread of the workpiece
Check the effective pitch diameter of the new through-end thread ring gauge
Single pitch diameter for checking the new through-end thread ring gauge
Complete
External thread profile
Truncate
External thread profile
Complete
Internal thread profile
Truncate
Internal thread profile
Complete
External thread profile
Truncate
External thread profile
Table 2 (Complete)
Rules for use
Should be screwed together with the internal thread of the workpiece
For the internal thread of the workpiece with four or less pitches, the sum of the screwing amount at both ends should not exceed two pitches; for the internal thread of the workpiece with more than four pitches, the screwing amount should not exceed two pitches|| tt||Should be screwed together with the external thread of the workpiece
For the external thread of the workpiece with four or less pitches, the screwing amount should not exceed two pitches;
For the external thread of the workpiece with more than four pitches, the screwing amount should not exceed 3X pitches
Should be screwed together with the new through-end thread ring gauge. It can be screwed together with the new through-end thread ring gauge partially, but it must not be screwed out from the other end
Rules for use
Calibration-loss|| tt||Thread plug gauge
Stop-through
Thread plug gauge
Stop-stop
Thread plug gauge
Stop-loss
Thread plug gauge
Through end smooth plug gauge
Non-end smooth plug gauge
Through end smooth ring gauge
Or caliper gauge
Non-end smooth ring gauge
Or caliper gauge
1128—1999|| tt||Check the through-thread in use
Ring gauge single middle diameter
Check the new stop-thread ring gauge
Single middle diameter
Check the stop-thread in use
Ring gauge single middle diameter
Check the internal thread minor diameter of the workpiece
Check the external thread major diameter of the workpiece
Truncate
External thread profile
Complete
External thread profile|| tt||External cylindrical surface
Inner cylindrical surface
or parallel
two planes
can be partially screwed on with the through-end thread ring gauge in use, but shall not be screwed out from the other end
should be screwed on with the new stop-end thread ring gauge throughCan be partially screwed on with the new stop-end thread ring gauge, but shall not be screwed out from the other end
can be partially screwed on with the stop-end thread ring gauge in use, but shall not be screwed out from the other end
should pass through the minor diameter of the internal thread of the workpiece
can enter the minor diameter of the internal thread of the workpiece, but the entry amount should not exceed one pitch
should pass through the major diameter of the external thread of the workpiece
should not pass through the major diameter of the external thread of the workpiece
4.3 In order to reduce disputes during inspection, the operator should use a new or less worn through-end thread gauge and a stop-end thread gauge that is more worn or close to the wear limit during the manufacture of the workpiece thread. When the inspection department or user representative inspects the workpiece thread, they should use the through-end thread gauge that is more worn or close to the wear limit and the stop-end thread gauge that is new or less worn. 5 Tolerance
5.1 The tolerance band of the thread ring gauge used to inspect the external thread of the workpiece and the calibration thread plug gauge used for the thread ring gauge is shown in Figure 1. The upper deviation of the middle diameter of the workpiece external thread
The lower deviation of the middle diameter of the workpiece external thread is
5.2 The tolerance band of the thread plug gauge used to inspect the internal thread of the workpiece is shown in Figure 2. 3
Upper deviation of the middle diameter of the internal thread of the workpiece
Lower deviation of the middle diameter of the internal thread of the workpiece
—1999
The middle diameter tolerance and related position element values ​​of the thread gauge are shown in Table 3. Table 3
>10~18
>18~30
>30~50
>50~80
>80~120
The half-angle tolerance of the thread gauge is shown in Table 4.
Note: The actual deviation of the half-angle of the thread profile can be positive or negative 5.5
The pitch tolerance of the thread gauge is shown in Table 5.
Thread gauge threaded portion length
>12~30
>30~50
>50~65
>65~80
JB/T1128-1999
Working thread gauge
Proofreading thread gauge
Note: Pitch tolerance is applicable to any number of teeth within the thread gauge length. The actual deviation can be positive or negative. 5.6 See Figure 3 for the dimension tolerance band of the gauge used to check the major diameter of the external thread of the workpiece. T. Upper deviation of the major diameter of the external thread of the workpiece
T. Lower deviation of the major diameter of the external thread of the workpiece
5.7 See Figure 4 for the dimension tolerance band of the gauge used to check the minor diameter of the internal thread of the workpiece. Upper deviation of the minor diameter of the internal thread of the workpiece
Lower deviation of the minor diameter of the internal thread of the workpiece
5.8 The dimensional tolerances of the smooth ring gauge or caliper gauge used to inspect the major diameter of the external thread of the workpiece and the smooth plug gauge used to inspect the minor diameter of the internal thread of the workpiece are shown in Table 6.5
Thread profile of thread gauge
Complete thread profile
JB/T1128—1999
>10~18
>18~30
>30~50
Designed according to actual conditions
By the manufacturer
>50-80
This standard does not specify the shape of the clearance groove and the bottom of the tooth. 6.1.1 The thread profile of the through-end thread ring gauge is shown in Figure 5. Figure 5
>80~120
6.1.2 The thread profile of the through-end thread plug gauge, the through-through thread plug gauge, the stop-through thread plug gauge, the stop-stop thread plug gauge and the stop-loss thread plug gauge is shown in Figure 6. This standard does not specify the shape of the clearance groove and the root of the tooth. Diameter
6.2 Shortened thread profile
6.2.1 The thread profile of the stop-end thread ring gauge is shown in Figure 7. This standard does not specify the shape of the clearance groove and the root of the tooth. 6
—1999
6.2.2 The thread profile of the stop-end thread plug gauge, the through-stop thread plug gauge and the through-loss thread plug gauge is shown in Figure 8. This standard does not specify the shape of the clearance groove and the root of the tooth.
The thread profile height F of the truncated thread profile is shown in Table 7. Table 7
7 Technical requirements
The surface of the thread gauge shall not have defects that obviously affect the appearance and quality of use. 0.6
7.2 The thread gauge shall be made of wear-resistant materials such as alloy tool steel, and its measuring surface hardness shall not be less than 53HRC, and the surface roughness R value shall be 0.63μm
The thread gauge shall be treated for stability.
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