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Classification number: Y17
Light Industry Standard of the People's Republic of China
QB/13548-1999
Replacement ZBTY17025-1988
Sewing machine
1999-04-21 Release
Synchronous belt
1999-04-21 Implementation
State Bureau of Light Industry
QB/T3548-1999
This standard belt is the original professional standard ZB/TY17025-[988 chain sewing machine synchronous belt, which was converted to QB/3548-1999 through the release of the document No. [1999] 112 of the Ministry of Light Industry. This standard is for the attention of the State Administration of Light Industry! This standard is under the jurisdiction of the National Center for Standardization of Sewing Machines. The main drafters of this standard are: Zhou Zaixiao, Li Minglu, and others. From the date of implementation, this standard will replace the professional standard ZR/TY17025-1988 issued by the Ministry of Light Industry. Contents and applicable scope of the People's Republic of China Light Industry Industry Standard QB/T3548-1999 Sewing Machine Timing Belt This standard specifies the size, length, width and corresponding limit deviation and quality regulations of the belt used in sewing machines. This standard is applicable to the annular synchronous belt (hereinafter referred to as the structural synchronous belt) with the requirements of synchronous motion and positive positioning of the chain mechanism transmission.
2 (see Figure 1)||tt| ... 3 Product classification
3.1 Specification model (see Figure 1 and Table 8) and comparison with foreign models (see Table 2) Approved by the National Light Industry Week on April 21, 1999
Implementation on April 21, 1999
ISO model
3,2 Dimensions
Q9/T35481999bzxz.net
1 Type and pitch of synchronous belts Pitch difference
Belt flyer
12,700
15,357
Table 2 Type comparison table
Nominal size of belt teeth (see Figure and Table 8)
Belt tooth pitch line length (see table).
Belt tooth style and tooth effect (see table).
is the nominal dimension of the tooth
with retraction
nominal dimension of the tooth
tooth root angle
HTYKoNKAa
0,6
specification drawing angle radius
QB/T3548-1S99
Table 1 Segment length and limit deviation recommendation
Segment length||t t||Basic ruler
.11z.z4
152,40
177,90
182,88
203, 30
228,6th
254,00
284,48
314,55
467,20||tt| |476,25
482,60
90,00
853,40
558,60
584,20
868,40
1F,200
12,c00
12,400
15,000
2 0,000
21,000
22,60u
23,000
2 yuan,000
25,500
26,oom
Unique limit difference
±0,46
±n,51
Number of edges on the length of the section
Section silk quality Lp
E19,15
e35,t5
1746,50
1255,40
1+47,60||t t||1600_20
737,14
813,92
10$4,28
1197,85
2 7,000
28,500
36_000
2-1,789
20,021
30,230
35,067
33,605
15,345
47,159
QB/T3548—1999
Root limit response
±(_51
±0,65
±0,85
±0,61
YYKASarKa-
Numbers on the shortened seat
Tongue line length
1289,99
1351,42
3.3 Mark|| tt||5H,351
QB/T3548—1999
The world's cost of loading length is determined by the manufacturer, width and limit of the load
I.ps.E38.20
The visual limit is uniform and the national supply mark is based on the product name, length, type, and standard components. D
L.p67e.40
QB/T3548--18
Synchronous Screen
420 D 050 ZEY 17025.
Standard No.
Book Width Code (0.6i×100)
Belt No. (42m×15)
4. Technical Basis
4. The nominal minimum shall comply with the provisions of Figure 2 and Table 3. 4.2 The length of the pitch line and the limit deviation shall comply with the provisions of Table 4, 4.3 The belt quotient and belt width shall comply with the provisions of Table 5. 4.4 Appearance
Appearance should be uniform and correct, with correct surface shape, no grain, grain, hole, scratch, spot, stain and other obvious defects.
4.5 Mechanical performance
The tensile performance, rotation performance and relative performance of the synchronous belt should meet the requirements of the table. 4.6 Oil resistance
After the oil resistance test, the density of the modified belt should not exceed 8%. 6
Interval belt
Strength
Last test
"long string"
For the special tire test
Yongyi Shenmin Law
, it is not greater than
. 1. Elongation is the ratio of the added force to the length shown in Table 9. HTYKoNKAa-
It cannot be stuck in the adhesive,
Special alcohol, plastic-free, etc.
The breaking force of the tooth||tt ||Surface oil test
Test quantity
Change rate
No more than
STest method
QB/T354B—1999
5.1 The outer dimensions of the synchronous belt shall be measured by conventional tools with corresponding accuracy according to the tolerances. 5.2 Check of the length of the gear
5.2.1 Measuring
The length of the gear shall be measured by the test equipment as shown in the figure, according to the provisions of Table 7, and with the gear of the same size as the tested belt. Two equal diameter pulleys are used, and the pulleys should be made according to the ratio shown in Table 7, and the interval between the pulley teeth and the theoretical belt spacing (see Figure 4) should comply with the specifications in Table 7. One pulley rotates freely on a fixed shaft, and the other pulley rotates on a movable shaft. 5.2.2 Measurement method
The synchronous belt is placed on the test device and its section length is determined.
The measuring force shown in Table 8 is applied to the moving pulley; when the synchronous belt section length is changed, the synchronous belt is rotated for at least two turns to make it Correct combination, uniform distribution of force: with the precision of D01, the center distance between the two pulleys is used to check the length tolerance of the synchronous belt. Dream edge
C (year,
section length
section length measuring device
help
Xie Jing synchronous belt length pulley
254,00
1R4,28
R8,859
board limit deviation
±0,013
External light
Minimum timing
stepping pipe
QB/T3548-1999
Minimum timing belt and energy measurement
Calculation of pitch line length
Where: Ip
Pulley width, 11P
I2C+Dp
Pulley pitch line length, m:
Center distance, mm;
D-effective diameter of the pulley, the third place after the small effective point. -TIY K/oN KAca-
5,3 External quality inspection
QE/T3548-1999
Under the natural light illumination of 600±2001z, magnetic inspection is carried out for two 300mm apart, and the daily measurement does not exceed 10mfm5.4 Mechanical model inspection
5.4.1 Tensile test
*. The sample adopts synchronous belt products, and 8 samples with a length of more than 250mm are taken from the same synchronous belt. The sample length is greater than 254mm and 26.4m is taken, and the sample length is less than 23.4m. The coefficient of the control table is 9, and the corrected value is divided according to formula (2). At an internal temperature of 30°C, the test device is clamped with a fixture, and a force is applied on the tensile test machine as shown in the table to measure the elongation value and convert it into tensile force. The elongation is about 50 mm, and the average value of the remaining values is taken from the samples cut off in the fire accumulation part, and the elongation is corrected. According to formula (3), the elongation is calculated.
Note: In the case of collecting 3 samples in one frame, 3 samples are collected from the same test. When the elongation is 25 mm, the original length is measured, 9
N/264.0
Formula F: Te—millimeter 251mm synchronous belt strength, kNT1-step joint strength, N;
Kh---solubility coefficient (Table 1D).
Formula, 1—original length of step belt, m
-synchronous length, m.
Prediction of the coefficient of tension Kt
5.4.2 Rotation test
Put the pulleys specified in the table and the test position shown in Figure 9 on the driving pulley and apply the measuring force specified in Table 9 to the driving pulley. The center distance of the two pulleys is: 5,3s
QB/T3548-1999
<. Fix the position of the driven pulley. After the driving pulley reaches a speed of 3500±100r/mi, release the fixed driving pulley under the same measuring force. After rotating for 5 seconds and stopping for 10 seconds, measure the center distance of the two belt pulleys: d. Calculate the true permanent elongation using formula (4).
Where: E is the permanent elongation;
E, is the center distance of the two belt pulleys before the test. m11E: The center distance between the two pulleys after the test, m. X
After the test, the sample should be checked for defects such as crazing, cracking, etc. 5.4, 3-tooth shear test
The sample adopts a belt product. Take 3 samples with a diameter of 25.4m and a length of 150m from the same synchronous belt,
b, clamp the test piece on a tool corresponding to the pulley tooth shape, use a tensile testing machine to measure the tearing force of the teeth, and stretch it at 25~50m/min, and take the average value of the 4 samples. 5.5 Shear test
. The sample is a synchronous product. Four samples with a width of 10mm (the actual width is reduced by 1mm) and a length of 50mm are cut from the same synchronous belt. 6. At room temperature (20°C), use a large scale with an accuracy of 1 to measure the oil volume: =, put the test piece into the test container, add 150m of torque oil! (The sample should be completely filled with the soft plug) Place it in a 40±1 constant temperature for 22h, take out the test piece, and cool it in the same special oil for 30~0°C. Then remove the surface residue in acetone: quickly remove the oxygen, and weigh the sample after oiling in a dense medium (4), and take the average value of the four samples. Calculate the weight change according to formula (5). W,-W,×100%
Wu Zhong: The weight change rate of the boundary line is %, %!
Measure again before the diameter sleeve, g!
：Wt--the benefit after receiving the thanks;
6. Inspection schedule
5.1 Inspection classification (see 11)
52 The creditor has the right to conduct acceptance inspection according to the factory inspection items specified in this standard. The composition of the inspection batch, sampling plan and schedule shall be determined by the supplier and the demander through negotiation.
HTYK6N KAa-1 Inspection classification (see 11)
52 The creditor has the right to conduct acceptance inspection according to the factory inspection items specified in this standard. The composition of the inspection batch, sampling plan and determination shall be determined by the supplier and the demander through negotiation.
HTYK6N KAa-1 Inspection classification (see 11)
52 The creditor has the right to conduct acceptance inspection according to the factory inspection items specified in this standard. The composition of the inspection batch, sampling plan and determination shall be determined by the supplier and the demander through negotiation.
HTYK6N KAa-
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