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GB 13651--1998
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Preface
This standard is based on the U.S. Federal Aviation Administration's Advisory Circular AC145-4 (1982) "Aviation Tire Inspection, Retreading, and Repair" The main technical content in the revision of GB13651-1992. In order to ensure the airworthiness of civil retreaded aviation tire products and to be in line with international trade, this standard adopts the corresponding content of AC145-4 for the inspection before and after retreading of aviation tires and the performance requirements of retreaded products. This is also The main differences between this standard and GB13651-1992.
This standard will replace GB13651-1992 from the date of implementation. Appendix A of this standard is a reminder appendix.
This standard is proposed by the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the National Aviation Tire Standardization Technical Committee. This standard was drafted by: Shuguang Rubber Industry Research and Design Institute of the Ministry of Chemical Industry, Civil Aviation Administration of China, Yinchuan Zhongce (Great Wall) Rubber Co., Ltd.
The main drafters of this standard are Huang Guiwu, Wu Suisheng, Lin Heyong, and Wang Huining. This standard was first published in September 1992.
This standard is entrusted to the National Aviation Tire Standardization Sub-Technical Committee for interpretation. 276
1 Scope
National Standard of the People's Republic of China
Retreaded aircraft tires
Retreaded aircraft tyre
GB 13651—1998
replaces GB13651 —1992
This standard specifies the inspection before retreading of civil retreaded aviation tires (referred to as retreaded tires), the technical requirements, test methods, inspection rules, marking, packaging and storage of retreaded products. This standard applies to civil retreaded aviation tires. 2 Referenced standards
The provisions contained in the following standards constitute provisions of this standard by being quoted in this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision and parties using this standard should explore the possibility of using the latest version of the standard listed below. GB/T532—1989 Determination of adhesive strength of vulcanized rubber and fabric GB9745—1995 Aviation tires
GB/T 9746—1995 Aviation tire series
GB/T11191—1989 Aviation tire burst pressure test method GB/ T11192-1989 Aviation tire static load performance test method GB/T11193-1998 Aviation tire outer edge size measurement method GB/T11194--1989 Aviation tubeless tire air tightness performance test method GB/T 13652--1992
Aviation Tire surface quality
Aviation tire X-ray detection method
GB/T 13653--1992
GB/T 13654-1992
Aviation tire holographic detection method| |tt||GB/T 13655--1992
GB/T 13656-1992
HG 2195-1991
3 definitions
Aerospace tire static balance difference test Methods
Test methods for physical properties of aviation tires
Use and maintenance of aviation tires
This standard adopts the following definitions.
3.1 Retread retread
refers to the method of renewing the tread of old tires or updating the sidewalls at the same time. It also includes the process of extending the new sidewall rubber to cover the tire pattern. Repair is within the scope of retreading .
retreaded aircraft tire
3. 2 Retreaded aircraft tireswww.bzxz.net
Aviation tires that can continue to be used after one or more retreads. 3.3 The number of retreads refers to the number of times an aviation tire is restored to a usable state after being retreaded. 3.4 Retread level
National Bureau of Quality and Technical Supervision approved on 1998-10-19 and implemented on 1999-04-01
277
GB 13651—1998
is a retread tire A characterization of a manufacturer's ability to retread old aircraft tires to a certain number of times. 4 Requirements
4.1 Inspection before aviation tire retreading
Whether the tire can be retreaded is determined by the following inspection method. a) Appearance inspection;
b) Non-destructive testing.
4.1.1 Retreadable tires
Tires with intact carcass and bead and flat spot wear that does not exceed one layer of carcass ply can be retreaded. The following situations can be repaired.
4.1.1.1 Tires with a rated speed greater than 193km/h a) Tread area: on the outermost carcass ply, cuts and cracks with a length and width not exceeding 38mm × 6.5mm, and the depth is not Up to 40% of the actual carcass ply can be repaired. For tread damage repaired by grinding and filing, the repair length shall not be greater than 50mm; b) Other damage to the tread: on the outermost carcass ply, the length shall not be greater than 38mm and the depth shall not be greater than 40% of the actual carcass ply. Tread damage of no more than six per tire and circumferential intervals of not less than 60° can be repaired; c) Sidewall parts: as long as the carcass ply is not damaged, radial and circumferential cracks, cuts or hidden injuries, etc. Surface defects can be repaired; d) Bead area: If the ply is not damaged, minor damage to the bead area can be repaired. The sealing performance of the bead should not be affected by indentations. The surface of the bead and the tire should be smooth: ||tt ||e) Tire toe area: The tire toe should be trimmed, and there should be no edges on the front of the bead. The remaining part of the vulcanized overflow rubber should not protrude more than 3mm on the front of the tire. If trimming is required, it should not be injured. and exposed carcass cords or more than one layer of chafer; f) Chafer: If the damage does not reach the ply layer, and there is no sign of delamination in the bead area, minor damage or bead damage on the chafer Minor mechanical damage to the site can be repaired. Loose or blistered chafers can be repaired or replaced: g) Airtight layer: Except for joints, surface damage or defects less than 50mm in length can be repaired, but not more than 10, and within a quarter There should be no more than three places within the circumference. For joints, damage or defects with a length less than 254mm can be repaired; h) Exposed lines: The exposed lines of the carcass reinforcing cords or carcass plies, each area should not exceed 1% of the entire tread polishing area or exposed The total area of ??the line does not exceed 2% of the entire tire. The exposed line depth should not exceed one layer of carcass ply. 4.1.1.2 Tires with a speed of less than or equal to 193km/h a) Damage to the bead area: Damage or looseness of the wrapping material is allowed to be repaired, small damage up to three plies but not exceeding 25% of the overall ply is allowed to be repaired;
b) Tread or sidewall damage can be partially repaired, but the length of the damaged tread area is less than 13m and the depth is not greater than the following requirements: number of ply layers
8
8~ 16
>16
4.1.2 Tires that cannot be retread
Maximum cutting depth
None
Two layers
Four layers| |tt|| After inspection, if the following conditions exist, the tires will not be retreaded or repaired and should be rejected. a) Damage other than damage to the bead wrapper, looseness, bead damage that does not extend to the carcass ply, or no signs of delamination in the bead area; b) Bead damage that affects the air-tightness performance of tubeless tires ;c) There is delamination and bubbling between the ply layers or around the bead; d) There is flexural fracture,
e) The bead is twisted or broken;
f) The depth reaches the carcass Aging cracks or radial cracks in the cord fabric; g) Cord looseness, internal damage and breakage; 278
GB 13651--1998
h) On the outside of the sidewall or shoulder area, the cord The wire is broken or cut; ji) The bead joint part is bulged or damaged by high temperature, causing the rubber material to return to its original state and peel off; k) The airtight layer is cracked, degraded and damaged greater than the provisions of 4.1.1.1g, 1) Local flat spot wear and drag tire burns that have damaged one layer of the carcass ply; m) oil contamination that affects surface adhesion or tire integrity n) sidewalls have been polished and patched three times;
) penetration Puncture damage to the carcass;
P) Tires with unclear markings and unknown manufacturers. 4.2 Requirements for aviation tires after retreading
4.2.1 Tread design
The tread of retreaded tires should have longitudinal grooves, or can be provided under any conditions of use in compliance with the requirements of the new tire manufacturer. Other tread designs for adequate traction.
4.2.2 Tread reinforcing ply
The end point of the tread reinforcing ply cannot be directly below the outer tread groove. 4.2.3 Weight
Unless otherwise specified, the weight of retreaded tires should not be greater than the tire weight range specified by the aircraft, or should not be greater than the maximum allowable value of new tire design.
4.2.4 Surface quality
In addition to the surface quality of retreaded tires, which should comply with the regulations of GB/T13652, the joint between the old and new surfaces of retreaded tires is allowed to be re-skinned, but it should be trimmed.
4.2.5 Inflated outer rim size
The inflated outer rim size of retreaded tires shall comply with the regulations of GB/T9746. 4.2.6 Static balance difference
The static balance difference of retreaded tires should comply with the static balance difference regulations of GB9745. 4.2.7 Balance mark
The red balance mark on the sidewall near the upper part of the bead should be maintained until the end of the retread tread life. 4.2.8 Dynamic performance
When retreaded tires are subjected to dynamic simulation tests, there should be no rotation between the test tire bead and the rim during the first five tests: this rotation should not damage the tubeless tire in subsequent tests. The bead inner liner of the tire may have an inner tube tire tube or valve. Retreaded tires after testing should not show any structural damage other than normal wear and tear. 4.2.9 Overpressure
Inflate no less than 3 times the rated inflation internal pressure at ambient temperature, and the retreaded tire should not burst for at least 3 seconds. 4.2.10 Internal defects
The internal defects of retreaded tires shall comply with the internal defect regulations of GB9745. 4.2.11 Air-tightness performance of tubeless retreaded tires The air-tightness performance of tubeless retreaded tires should comply with the air tightness regulations of tubeless tires in GB9745. 4.2.12 Physical properties
The physical properties of retreaded tires should include the tensile strength of the tread rubber, elongation at break, permanent deformation at break, set elongation strength, and the difference between the retread and the polished tread. And the bonding strength between the third and fourth plies from the outside to the inside of the carcass, etc.; performance indicators should comply with the design regulations of retread tires.
4.2.13 Air holes
Tubeless tires and tubed tires with an inflation internal pressure higher than 686kPa, after retreading, when the air holes on the original tire body are covered with retreading materials, they should be designed Re-pierce the air vent at the location specified in the drawing. The hole depth should not reach the inner liner of the tubeless tire. The tire eyelet position 279
is marked with a white dot.
4.3 Retreading level verification
GB 13651-1998
The retreaded tire manufacturer should verify the retreading level. See Appendix A (Appendix of Prompts) for specific requirements. 5 Sampling
5.1 Product Acceptance
Retreaded tires shall be inspected by the quality inspection department of the manufacturer in accordance with the provisions of this standard. After passing the inspection, the representative of the ordering party shall accept the tires at their own expense. 5.2 Inspection Classification
Inspection is divided into two categories: factory inspection and type inspection. Factory inspection refers to various inspections that must be carried out when products are delivered. Type inspection refers to a comprehensive assessment of product quality, that is, all technical requirements specified in this standard are inspected. Type inspection is generally required when one of the following situations occurs: a) Retreaded tires of different specifications, levels, and brands before being put into retreading production; b) After formal production, if the structure, materials, and processes are significantly changed, product performance may be affected. when, c) when the national quality supervision agency proposes a request for type inspection. 5.3 Inspection Items
5.3.1 Outbound Inspection
The factory inspection is a full inspection.
a) Surface quality;
b) Static balance difference;
c) Internal defects.
5.3.2 Type inspection
Type inspection is random inspection. Two retreaded tires are sampled each time, one for dynamic simulation testing and the other for testing of other items. Type inspection includes the following items:
a) Inflated outer rim size;
b) Weight;
c) Overpressure:
d) Air tightness of tubeless retreaded tires Performance;
e) Physical performance:
f) Dynamic simulation performance.
5.4 Judgment Rules
5.4.1 Those that fail to pass the inspection of surface quality and internal defects in accordance with the provisions of this standard shall be rejected. 5.4.2 If the static balance difference fails to pass the test according to this standard, patch balancing should be performed. 6 Test methods
6.1
The surface quality inspection of retreaded tires shall be carried out by visual inspection. 6.2 Internal defect inspection shall be carried out in accordance with the provisions of GB/T13653 or GB/T13654. 6.3 The dimensions of the inflatable outer edge are measured according to the provisions of GB/T11193. 6.4 The determination of static balance difference shall be in accordance with the provisions of GB/T13655. 6.5 Retreaded tires should undergo 50 take-off tests and 8 taxi tests under rated load. The dynamic performance test is in accordance with the provisions of GB9745. 6.6 The overpressure performance test shall be in accordance with the provisions of GB/T11191. 6.7 The air tightness performance test of tubeless tires shall be in accordance with the provisions of GB/T11194. 6.8 The physical performance test of retreaded tires shall be in accordance with the provisions of GB/T13656. 280
GB 13651-1998
6.9 Products provided by the supplier for acceptance by the orderer should be accompanied by a product acceptance certificate. , the product acceptance certificate should include the following contents: a) product acceptance card;
b) product serial number,
c) internal defect non-destructive testing report;
d) static balance test report ;
e) Product Certificate of Qualification.
7 Marking, packaging, storage and use
7.1
After tire retreading, in addition to the permanent markings required for original new tires, the following markings must be added, among which a)~ e) is a permanent mark: a) name or code of tire retreading factory,
b) address of tire retreading factory,
c) date and serial number of tire retreading,
d) retreading Number of times (indicated by the letter "R followed by a number, such as the third retreading, expressed as R3 or R-3); e) Standard number of retreaded tires performed:
f) Inspection seal.
2 Packaging
7.2
The packaging method shall be negotiated between the supplier and the orderer: 7.3
3 Storage and use
The storage and use of retreaded tires shall comply with HG2195. Provisions 281
A1 test purpose
GB 13651--1998
Appendix A
(prompted appendix)
Renovation level verification test||tt ||The retread level verification test is an assessment of the retread tire manufacturer's carcass screening capabilities and retreading process technology capabilities to ensure that the retread tire manufacturer's products meet the minimum airworthiness standards
Retread level verification. The following inspections and tests should be carried out during the test. a) Appearance inspection;
b) Air needle inspection:
c) Internal defect detection;
d) Tread and carcass bonding Strength test.
A3 test method
A3.1 Appearance inspection is carried out by visual inspection. A3.2 Air needle inspection is to insert the air needle from the sidewall of the upper part of the tire bead at a certain angle. It is inserted between the ply layers of the carcass, and the gas is forced into the carcass through pressure. After a period of time, if there is a leak in the airtight layer, the gas escapes from the leaking site and causes the solution applied on the surface to bubble. If there is delamination of the ply layer , there are blisters and bulges in the delamination part. During the test, the airtight layer shall not be pierced. A3.3 Internal defects shall be inspected according to the provisions of GB/T13652 or GB/T13653. A3.4 The bonding strength of the tread and carcass shall be as follows. Specified inspections: a) Tread bonding strength test
Cut three samples from each tire at 120° intervals on the tread. The sample preparation method is in accordance with 9.1.1 and 9.1 of GB/T13656-1992. 2 and 9.1.5 shall be followed, and then the bonding strength of the retread and polished interface shall be measured according to the method specified in GB/T532. Take the average of three test results for each tire;
b) Carcass ply. Adhesion strength test
Use the above-mentioned sample to measure the adhesion strength between the third and fourth layers of the carcass ply (from outside to inside). Take the average of three test results for each tire. | tt | , that is, 20 retreaded tires of different specifications, users, and brands are selected from all produced products for the test specified in A2. If the composition of the sampled tires is uneven, the sampling should focus on high-speed tires with larger loads. The retread level shown in the 20 sample tires depends on the number of tires of each retread level. The tires to be inspected are new retreads. For example, R4 represents a retread of an old tire that has been retreaded three times. See Table A1. A4.2 For retreaded tire manufacturers that will be engaged in retreading production, they should conduct the tests specified in A2 starting from the verification of R1 level according to Table A1. A4.3 Retreaded tire manufacturers that have obtained a certain retreading level certification should verify the new specifications of retreaded tires. When, it should be in accordance with 4. of this standard.2. Inspections and tests are required to verify the R1 level. If the retreading level is upgraded in the future, the adhesion strength test of the retreaded tires shall be carried out according to the number of specimens specified below.
a) R2 level, two retreaded tires;
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b) R3 level, three retreaded tires;
GB13651—1998
c) R4 and above, one retreaded tire for each level; d) Retreaded tires at each level can be put into use without testing, but the next level of retreading cannot be carried out before the bond strength test is completed at that level. Retreaded tires with defects that do not affect bonding can be used for bonding strength testing. Table A1 Number of refurbishment level verification tests
Qualified refurbishment level
Renovation
Number of times
R1
The minimum sample size must be guaranteed at each refurbishment level Quantity R2
R3
R4
R5
R6
R7
R8
R9
R10
R11
R12
Total
R1
20
20
R2
15|| tt||5
20
R3
15
5
20
R4
+||tt| |15
5
20
R5
5
10
5
20
R6
5
10
5
20
R7
10
5
20|| tt||R8
5
10
5
20
R9
5
10||tt| |5
20
R10
5
10
5
20
R11
5
10
5
R12
5
10
5
20
Note: Along In the longitudinal direction of Table 1, the number of tires for each level of retreading can be found. For example, a retreading factory that has reached the R3 retreading level has tested at least 20 R1 tires, 15 R2 tires and 5 R3 tires. To verify whether the R4 retreading level is qualified, the manufacturer must also test 10 more R3 tires. and 5 R4 tires. To reach the R5 level, 5 more R4 tires and 5 R5 tires must be tested. A4.4 For retread tire manufacturers that have obtained a certain level of retreading certification, the level of retreading in the future should be increased step by step, and upgrade verification should be carried out according to the sampling regulations in Table A1 and the items specified in A2. A5 Result Judgment
A5.1 Appearance inspection results comply with the provisions of 4.2.4. A5.2 Bubbles should not appear during air needle inspection. A5.3 Internal defect detection complies with the provisions of 4.2.10. A5.4 Requirements for the bonding strength of the retread and polished interface. Among the 20 test tires, the bonding strength of the four retreaded tires with the smallest bonding strength meets the following requirements: the bonding strength of the first tire is not less than 5.25kN/m, The bonding strength of the second strip is not less than 5.78kN/m, the bonding strength of the third strip is not less than 6.30kN/m, and the bonding strength of the fourth strip is not less than 6.83kN/m. A5.5 Carcass ply bonding strength requirements Among the 20 test tires, the bonding strength of the four retread tires with the smallest bonding strength meets the following requirements: the bonding strength of the first tire is not less than 3.5kN/m, the bonding strength of the second tire is not less than 3.5kN/m, The bonding strength is not less than 4.03kN/m, the third bonding strength is not less than 4.55kN/m, and the fourth bonding strength is not less than 5.10kN/m. A5.6 If the 20 test tires do not meet the specified standards, 20 more test tires can be selected for retesting. If the retest results still do not meet the specified standards, the proficiency verification has failed.
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