SAE J2494-3-2002(R 2007)

SAE 美国 汽车 行业 标准

SURFACE VEHICLE STANDARD

J2494-3

REV. AUG2007

Issued 2002-07

Revised 2007-08

Superseding J2494-3 JUL2002

Performance Requirements for SAE J844 Non-Metallic Air Brake Tubing and Push to Connect Fitting Assemblies Used in Vehicular Air Brake Systems

RATIONALE

The modifications to this document are to harmonize the requirements of SAE J1131 and SAE J2494-3 where applicable. 1. SCOPE

This SAE Standard is intended to establish uniform performance criteria and methods of testing push to connect tube fittings, with SAE J844 air brake tubing as used in vehicular air brake systems.

The specific tests and performance criteria applicable to the tubing are set forth in SAE J844. The test values contained in this performance standard are for test purposes only. For environmental and usage limitations, see SAE J844. 1.1 General Requirements

a. Test temperature shall use ±3 °C as the test tolerance range. b. Ambient temperature shall be 24 °C.

c. All test times are minimum times unless otherwise specified. d. Dry Air shall be a minimum of –50 °C dew point. e. Tubing shall be cut square at 90 degrees ± 7 degrees.

f. Precondition all test specimens at 700 kPa ± 70 kPa for 30 s without any leakage. g. New specimens shall be used for all tests. 2. REFERENCES

2.1 Applicable Publications

The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply.

__________________________________________________________________________________________________________________________________________ SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright © 2007 SAE International

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE.

TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada)

Tel: 724-776-4970 (outside USA)

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2.1.1 SAE Publications

Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), . SAE J844 SAE J2024 SAE J2494-1 SAE J2494-2 SAE J2494-4

Nonmetallic Air Brake System Tubing

Contaminants for Testing Air Brake Components and Auxiliary Pneumatic Devices

Dimensional Specifications for Metallic Body Push-to-Connect Fittings Used on a Vehicular Air Brake System

Dimensional Specifications for Non-Metallic Body Push-to-Connect Fittings Used on a Vehicular Air Brake System Cartridge Cavity

SAE HS J806 SAE Oil Filter Procedure 2.1.2 ASTM Publications

Available from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, . ASTM B 117

Salt Spray (Fog) Testing

ASTM D 4329 Standard Practice for Fluorescent UV Exposure of Plastics ASTM G 53 ASTM G 151 ASTM G 154

Practice for Operating Light- and Water-Exposure Apparatus (Fluorescent UV-Condensation Type) for

Exposure on Nonmetallic Materials

Standard Practice for Exposing Nonmetallic Materials in Accelerated Test Devices that Use Laboratory Light Sources

Practice for Operating Fluorescent Light Apparatus for UV Exposure of Nonmetallic Materials

2.1.3 Federal Publication

Available from the Superintendent of Documents, U.S. Government Printing Office, Mail Stop: SSOP, Washington, DC 20402-9320.

DOT FMVSS 571.106 (49CFR 571.106)

Brake Hoses

3. REQUIREMENTS FOR METALLIC AND NON-METALLIC FITTINGS 3.1

Tensile Tests (15 specimens)

3.1.1 Description

Both hot and cold tensile tests shall be conducted with different unaged assemblies (fittings attached within 30 days of test date). Tests consist of subjecting the assembly to increasing tensile load in a suitable testing machine until the specified force value or elongation percentage has been obtained.

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SAE 美国 汽车 行业 标准

3.1.2 Apparatus

A tensile test machine with suitable indicating device shall be used for the tensile test. The fixtures for holding the test specimens shall be arranged so the tubing and fittings have a straight centerline corresponding to the direction of the machine pull. The lower part of the fixture shall be equipped with a container of sufficient dimensions to submerge the required length of tubing in water. A means of heating the water to boiling shall be provided. A cover shall not be used on the container. This allows the steam to dissipate into the environment. If a fan is used in this test, then take precautions to direct the air away from the test specimen. 3.1.3 Test Specimens

The tubing specimens (a minimum of 15) shall be obtained from current production stock and cut to a length sufficient to obtain 150 mm ± 6 mm of tubing between end fittings after assembly. Assemble fittings to the tubing using the manufacturer's recommendations. 3.1.4 3.1.4.1

Procedure (15 specimens)

High Temperature Tensile Test (5 specimens)

Place the test specimen in the tensile machine with the lower fitting and 102 mm (+6/–0 mm) of tubing submerged below the surface of the boiling distilled water such that the outside diameter is exposed to the water. Continue boiling for 5 min (+0.5/–0 min). Apply load at a rate of pull of 25 mm/min. 3.1.4.2

Conditioned Tensile Test (5 specimens)

Condition test specimen at –40 °C for 30 min (+0.5/–0 min), normalize at ambient temperature then submerge in boiling water for 15 min. Repeat for a total of four complete cycles. Allow the test specimen to normalize at room temperature for 30 min. Conduct the tensile test within 30 min after the normalizing period while at ambient temperature of 24 °C. Apply load at a rate of 25 mm/min. 3.1.4.3

Water Absorption and Tensile Test (5 specimens)

After immersion in distilled water at ambient temperature for 70 h, conduct tensile test on the specimen by applying a load at the rate of 25 mm/min. The tube assembly shall withstand without separation of the tube and end fittings a tensile pull as listed in Table 1. 3.1.5

Acceptance Criteria – Requirements

Each specimen shall elongate 50% (min), that is 150 mm increased to 225 mm, or shall withstand the load listed in Table 1 without causing separation from the fitting.

TABLE 1 - TENSILE REQUIREMENTS Nominal Tubing OD (in)

Tensile Load (Newtons)

5/32 225 3/16 225 1/4 225 5/16 335 3/8 670 1/2 900 5/8 1450 3/4 1560

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3.2

Air Leakage (5 specimens)

3.2.1 Description

This test is designed to evaluate the effects of high and low system pressures on the fitting assembly at high and low temperatures. 3.2.2 Apparatus

The equipment must be capable of controlling the ambient air temperature between –40 °C and 104 °C while applying 1035 kPa or 70 kPa dry air to the test lines. A mass flow meter capable of determining air leakage shall be provided. 3.2.3 Test Specimens

Cut tubing specimens to a length sufficient to obtain 460 mm between fittings after assembly. Assemble identical fittings to the tubing using the manufacturer's recommendations. 3.2.4 Procedure

Place both ends of the test specimens in temperature cycling cabinet and connect to a pressure source capable of 70 kPa ± 7 kPa and 1035 kPa ± 70 kPa pneumatic pressure. Pressure 4 c/h, alternating between 70 kPa ± 7 kPa and 1035 kPa ± 70 kPa. Subject the test specimens while under pressure to ambient temperature for 2 h, 104 °C for 12 h, ambient temperature for 2 h, –40 °C for 2 h, and ambient temperature again for 2 h in the order listed. See Table 2 and Figure 1.

TABLE 2 - AIR LEAKAGE TEST CONDITIONS Time (hours)

Pressure (kPa)

Temperature (°C)

24 104 24 –40 24

2 1035 14 1035 16 1035 18 1035 20 1035

FIGURE 1 - AIR LEAKAGE TEST CYCLE CHART

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3.2.5 Acceptance Criteria

After the pressure in the assembly is allowed to stabilize, the test specimens are considered a failure if the average leakage per fitting on any assembly at specified test conditions in Table 2 exceeds the amounts listed in Table 3.

TABLE 3 - LEAKAGE TEST REQUIREMENTS

Test Temperature (°C)

Maximum Leakage (Standard Cubic Centimeters/Minute)

104 3 24 5 –40 7

3.3

Vibration Test (5 specimens)

3.3.1 Description

This test is designed to evaluate the effects of vibration on a tube and fitting assembly under varying internal pressures and ambient temperatures. Leakage rate is used to gauge acceptability. 3.3.2 Apparatus

Equipment capable of vibrating one end of the test specimen at 600 Hz through 12 mm displacement in a plane perpendicular to the tube while the other end is held rigid. The distance between the static and vibrating head is to be such, that when the assembly is displaced 12 mm, no parallel pull to the longitudinal axis of the assembly will occur. The equipment must be capable of automatically adjusting the system pressure to compensate for fluctuating temperatures between –40 °C and 104 °C and associated air pressure of 830 kPa (±70 kPa) dry air during the test process. A mass flow meter capable of determining air leakage shall be provided. 3.3.3 Test Specimens

Allowing 12 mm slack, cut a minimum of 5 tubing specimens to a length sufficient to obtain 460 mm between fittings after assembly. Assemble identical fittings to the tubing using the manufacturer's recommendations. 3.3.4 Procedure

Allowing 12 mm slack, mount the lines straight in the vibration machine. Oscillate one end of the lines at 600 cycles/minute (±20 cpm) through a total stroke of 12 mm for a total of 1 000 000 cycles (+ 50 000/–0 cycles), while maintaining test conditions as shown in Table 4. Starting at 104 °C, vary the ambient air temperature from 104 °C to -40 °C at 250 000 vibration cycle intervals, approximately 7 h intervals. Using a mass flow meter, observe for fitting leakage during and after the test.

TABLE 4 - VIBRATION TEST REQUIREMENTS Test Cycles 0/250 000 250 001/500 000 500 001/750 000 750 001/1 000 000

3.3.5 Acceptance Criteria

The test is considered a failure if the average leakage per fitting on any assembly at test temperatures exceeds the amounts listed in Table 3.

Test Pressure (kPa) Test Temperature (°C)

0 0 830 830

104 –40 104 –40

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SAE 美国 汽车 行业 标准

3.4

Fitting Separation Pressure Test Requirements (5 specimens)

3.4.1 Description

This test is intended to evaluate fitting retention at proof pressure of 2760 kPa ± 70 kPa and at minimum separation pressure.

3.4.2 Apparatus

The test apparatus consists of a suitable source of hydraulic pressure and the necessary gauges and piping. 3.4.3 Test Specimens

Cut a minimum of 5 tubing specimens to obtain 300 mm between fittings after assembly. Assemble fittings to the tubing using the manufacturer's recommendations. 3.4.4 Procedure

Plug one end of the test specimen and mount in the apparatus with the end unrestrained. Apply proof pressure at ambient temperature, to the test specimen and hold for 30 s. Increase pressure at a constant rate so as to reach the specified minimum separation pressure within a time period of 3 to 15 s. 3.4.5 Acceptance Criteria

Fittings shall not separate from the tubing nor shall the assembly visibly leak at less than specified minimum separation pressure of 5500 kPa ± 70 kPa. 3.5

Frozen Water Retention Test (5 specimens)

3.5.1 Description

This test is intended to evaluate the effects of frozen water on fitting retention while assembly is pressurized to 2760 kPa ± 70 kPa.

3.5.2 Apparatus

The test apparatus consists of a suitable source of pneumatic pressure and the necessary gauges and piping. 3.5.3 Test Specimens

The tubing specimens shall be obtained from current production stock and cut to a length sufficient to obtain 150 mm ± 6 mm of tubing between end fittings after assembly. Assemble fittings to the tubing using the manufacturer's recommendations. 3.5.4 Procedure

Submerge one end of fitting assembly in water for 15 s, then remove the specimens from the water making sure the orientation of the fitting is such that no water is allowed to drain. Place test specimens in –10 °C air for a minimum of 1 h or until completely frozen. Conduct pressure test on the specimens while at –10 °C by applying 2760 kPa ± 70 kPa pneumatic pressure and hold for 5 min. 3.5.5 Acceptance Criteria

Fittings shall not separate from the tubing at the specified minimum test pressure of 2760 kPa.

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SAE 美国 汽车 行业 标准

3.6

Reassembly Test (5 specimens)

3.6.1 Description

This test is intended to evaluate the effects of repeated assembly and disassembly of a tube and fitting. Leakage rate is used to gauge acceptability. 3.6.2 Apparatus

The test apparatus consists of a suitable source of pneumatic pressure and the necessary gauges and piping. A mass flow meter capable of determining air leakage shall be provided. 3.6.3 Test Specimens

Cut a minimum of 5 tubing specimens to obtain 300 mm between fittings after assembly. Assemble fittings to the tubing using manufacturer's recommendations. 3.6.4 Procedure

The tube and fitting connections shall be assembled, pressurized to 830 kPa ± 70 kPa pneumatic for 5 min (+0.5/-0.0 min), depressurized and disassembled five times. Tube end must not be trimmed between each assembly and disassembly cycle. Reassemble a sixth time and pressurize the test specimen to 830 kPa ± 70 kPa with pneumatic pressure at ambient temperature, hold for 5 min and check for leakage. 3.6.5 Acceptance Criteria

The test is considered a failure if the average leakage per fitting on any assembly at test temperatures exceeds the amounts listed in Table 3. 3.7

Oil Compatibility Test (5 specimens)

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3.7.1 Description

This test is intended to evaluate the effects of contaminated compressor oil as described in SAE J2024 Section 3 at high and low temperatures on fitting performance. 3.7.2 Apparatus

The test apparatus consists of a suitable source of hydraulic pressure, 1035 kPa and necessary gauges and piping in environmental test chambers at 100 °C and –40 °C. 3.7.3 Test Specimens

Cut a minimum of 5 tubing specimens to obtain a minimum of 300 mm between fittings after assembly. Assemble fittings to the tubing using manufacturer's recommendations. 3.7.4 Procedure

Fill test specimens with contaminated oil mixture consisting of 11 parts SAE 15W40CD type oil and 1 part SOFTC-2A contaminates. Subject specimens to 100 °C, and atmospheric pressure for 72 h (+1/–0.0 h), then apply internal pressure of 1035 kPa ± 70 kPa for 5 min while maintaining temperature of 100 °C. Reduce to atmospheric pressure and permit test specimens to return to ambient temperature then subject test specimens to –40 °C and atmospheric pressure for 24 h (+1/–0.0 h). Then apply internal pressure of 1035 kPa ± 70 kPa for 5 min (+0.5/–0.0 min) while maintaining a temperature of –40 °C.

SAE 美国 汽车 行业 标准

3.7.5 Acceptance Criteria

Tubing shall not rupture or disconnect from the fittings. 3.8

Fitting Assembly Corrosion Resistance Test (5 specimens)

3.8.1 Description

This test is designed to test the effects of salt spray corrosion on fitting assembly performance. 3.8.2 Apparatus

Utilize the apparatus described in ASTM B 117 Salt Spray (Fog) Testing. Mix a salt solution five parts by weight of sodium chloride to 95 parts of distilled water, using sodium chloride substantially free of nickel and copper, and containing on a dry basis not more than 0.1% of sodium iodide and not more than 0.3 percent of total impurities. Ensure that the solution is free of suspended solids before the solution is atomized. After atomization at 35 °C, ensure that the collected solution is in the pH range of 6.5 to 7.2. Make the pH measurement at 25 °C. Maintain a compressed air supply to the nozzle or nozzles free of oil and dirt and between 70 and 170 kPa. The test specimens shall be supported or suspended 30 degrees from the vertical and parallel to the principal direction of the horizontal flow of fog through the chamber. The test specimens shall not have contact with any metallic material or any material capable of acting as a wick.

Condensation that falls from the test specimens shall not return to the solution reservoir for respraying. Condensation from any source shall not fall on the test specimen or the solution collectors. Spray from the nozzles shall not be directed onto the test specimens. 3.8.3 Test Specimens

The test specimens shall consist of two end fittings and a minimum of 200 mm of tubing between fittings. 3.8.4 Test Procedure

Subject the test specimens to the salt spray continuously for 72 h (+1/–0.0 h). Regulate the mixture so that each collector will collect from 1 to 2 ml of solution per hour for each 80 cm2 of horizontal collecting area. Maintain exposure zone temperature at 35 °C. Upon completion, remove the salt deposit from the surface of the tube assembly by washing gently or dipping in clean running water not warmer than 38 °C and then drying immediately. Allow the test specimens to stabilize at ambient temperature, then pressurize to 840 kPa ± 70 kPa pneumatic pressure for 5 min. 3.8.5 Acceptance Criteria

After 72 h exposure to salt spray, the fittings shall show no pit corrosion on the fitting surface. The average leakage per fitting on any assembly shall not exceed in amount listed in Table 3. 3.9

Side Load Leakage Test (5 specimens)

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3.9.1 Description

This test is designed to evaluate the leakage effects of maximum side loading on a tube and fitting assembly at ambient temperature. Leakage rate is used to gauge acceptability. 3.9.2 Apparatus

Equipment must be capable of controlling air pressure to 1035 kPa through a manifold consisting of a fixed and an adjustable block (see Figure 2). A mass flow meter capable of determining air leakage shall be provided.

SAE 美国 汽车 行业 标准

FIGURE 2 - SIDE LOAD TEST FIXTURE

3.9.3 Test Specimens

Prepare test specimens using straight tube fittings. The length of tubing shall be determined by the following formula: Test specimens length = π(minimum kink radius1) + 2 (fitting insertion depth). 3.9.4 Test Procedure

Mount test specimens on test manifold blocks using identical tube fittings as shown in Figure 2. Using the adjustable block, increase the distance between the centerlines of the test fittings to equal the test distance listed in Table 5. Pressurize the test specimens to 1035 kPa at ambient temperature for a period of 5 min. If the tubing kinks during the test, the test shall be restarted using another specimen of tubing.

TABLE 5 - SIDE LOAD TEST REQUIREMENTS Nominal Tubing OD (in)

Test Distance (mm)

5/32 30 3/16 50 1/4 65 5/16 80 3/8 95 1/2 127 5/8 160 3/4 180

3.9.5 Acceptance Criteria

After 5 min, the test is considered a failure if the average leakage per fitting on any assembly at test temperature exceeds the amount listed in Table 3.

4. ADDITIONAL REQUIREMENTS FOR NON-METALLIC FITTINGS ONLY 4.1

Moisture Absorption (5 specimens)

4.1.1 Description

This test is designed to evaluate the resistance of non-metallic fitting components to moisture absorption. Change in weight is used to gauge acceptability.

1

As listed in SAE J844 Table 3.

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4.1.2 Apparatus

Equipment must be capable of controlling air temperature within a temperature range of ambient temperature to 110 °C and relative humidity of 100% at ambient temperature. 4.1.3 Test Specimens

Unassembled non-metallic fitting components. 4.1.4 Test Procedure

Expose all specimens of non-metallic components for 24 h in a circulating air oven at 110 °C. Remove from oven, weigh immediately and expose for 100 h at 100% relative humidity and ambient temperature. Within 5 min from humidity conditioning, remove surface moisture from both interior and exterior surfaces of the non-metallic components and re-weigh.

4.1.5 Acceptance Criteria

Moisture absorption of each non-metallic components shall not exceed 2% by weight. 4.2

Ultraviolet Resistance (5 specimens)

4.2.1 Description

This test is designed to evaluate the resistance of non-metallic fittings to ultraviolet radiation exposure. 4.2.2 Apparatus

A more complete description of the apparatus may be found in ASTM D 4329. Use fluorescent UV apparatus that conforms to the requirements defined in ASTM G 151 and G 154 is required to conform to this practice. Unless otherwise specified, the spectral power distribution of the fluorescent UV lamp shall conform to the requirements in ASTM G 154 for a UVA 340 lamp.

4.2.3 Test Specimens

Cut tubing specimens to obtain 300 mm between fittings after assembly. Assemble fittings to the tubing using the manufacturer's recommendations. 4.2.4 Test Procedure

Place specimens of non-metallic fittings in the specimen racks of a Q-Panel QUV test apparatus. Expose for 300 h minimum. If the test apparatus is equipped with a “Solar Eye”, the bulbs need not be rotated and the irradiance should be set at 0.85, however all bulbs should be discarded after 4800 h maximum or if they fall below the 0.85 irradiance level, whichever occurs first. If the test apparatus is not equipped with a “Solar Eye”, the bulbs must be rotated every 400 h maximum, as recommended by the manufacturer and ASTM G 53, this procedure will result in discarding lamps after 1600 h of use. Maintain test temperature of 45 °C ± 3 °C. The distance from the plate upon which the specimens are mounted and the light bulbs will be 51 mm maximum. The automatic humidity cycling must be turned off. Rotate the specimens according to ASTM D 4329 except the time interval should be each 96 h maximum, instead of weekly. Maintain and operate QUV tester in accordance with manufacturer instructions. Immediately following this exposure, stabilize the fitting for 0.5 to 3.0 h at ambient temperature and subject the fitting to a hydrostatic pressure test. 4.2.5 Acceptance Criteria

Fitting shall withstand a minimum internal pressure of 4400 kPa within a time period of 3 to 15 s.

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SAE 美国 汽车 行业 标准

4.3

Zinc Chloride Resistance (5 specimens)

4.3.1 Description

This test is designed to evaluate the resistance of non-metallic fittings to Zinc Chloride. Visual evidence of cracking is used to gauge acceptability. 4.3.2 Test Procedure

Immerse non-metallic fitting in a 50% (by weight) aqueous solution of Zinc Chloride, pressurize assembly to 830 kPa ± 70 kPa for 200 h at ambient temperature. Remove from solution.

NOTE: Fresh, anhydrous zinc chloride should be used to make up a concentration of 50% (by weight) aqueous solution.

(sg of 1.576 or a Baume rating of 53 degrees at 15.6 °C). 4.3.3 Acceptance Criteria

Fitting shall show no evidence of cracking on outside surfaces after pressurizing at 4400 kPa ± 70 kPa for 30s. 4.4

Methyl Alcohol Resistance (5 specimens)

4.4.1 Description

This test is designed to evaluate the resistance of non-metallic fittings to Methyl Alcohol. Visual evidence of cracking is used to gauge acceptability. 4.4.2 Test Procedure

Immerse non-metallic fitting in 95% Methyl Alcohol for 200 h at ambient temperature. Remove from solution. 4.4.3 Acceptance Criteria

Fitting shall show no evidence of cracking on outside surfaces after pressurizing at 4400 kPa ± 70 kPa for 30 s. 4.5

Cold Temperature Impact (6 specimens)

4.5.1 Description

This test is designed to evaluate the resistance of non-metallic fittings to Cold Temperature Impact. Leakage rate is used to gauge acceptability. 4.5.2 Apparatus

Equipment must be capable of controlling air temperature within a temperature range of –40 °C to 110 °C. Impact apparatus as shown in Figure 3. 4.5.3 Test Specimens

Cut tubing specimens to obtain 300 mm between fittings after assembly. Assemble fittings to the tubing using the manufacturer's recommendations.

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SAE 美国 汽车 行业 标准

4.5.4 Test Procedure

Condition three specimens for 24 h in a circulating air oven at 110 °C. Additionally, condition three specimens in distilled boiling water for 2 h. Remove all specimens from conditioning and allow to stabilize at ambient temperature for 1 h. Expose all specimens and impact test apparatus, shown in Figure 3, to –40 °C for 4 h. While fitting and test apparatus are at cold temperature (approximately –40 °C), subject fitting to impact by placing the fitting in the apparatus as shown in Figure 3 and allow the falling weight to free fall on the weakest zone of the fitting. The falling weight shall be mounted in a tubular housing or track in such a way as to permit free and unrestricted movement.

4.5.5 The distance between the bottom of the falling weight and the point of impact with the fitting shall be equal to

300 mm. After impact testing allow the fitting to stabilize at ambient temperature. Within 30 min of stabilization, subject fitting to hydrostatic pressure of 4400 kPa within a time frame of 3 to 15 s. 4.5.6 Acceptance Criteria

Fittings shall not show any evidence of cracks or leakage. 5. NOTES

5.1 Marginal Indicia

The change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions have been made to the previous issue of the report. An (R) symbol to the left of the document title indicates a complete revision of the report.

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FIGURE 3 - COLD IMPACT TEST FIXTURE

PREPARED BY THE SAE S-4 AIR BRAKE TUBING AND FITTINGS SUBCOMMITTEE OF THE SAE FLUID CONDUCTORS AND CONNECTORS TECHNICAL COMMITTEE