1、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 entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefro
2、m, 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.QUESTIONS REGARDING THIS DOCUMENT: (724) 772-8512 FAX: (724) 776-0243TO PLACE A DOCUMENT
3、 ORDER; (724) 776-4970 FAX: (724) 776-0790SAE WEB ADDRESS http:/www.sae.orgCopyright 1998 Society of Automotive Engineers, Inc.All rights reserved. Printed in U.S.A.SURFACEVEHICLE400 Commonwealth Drive, Warrendale, PA 15096-0001STANDARDSubmitted for recognition as an American National StandardJ2436I
4、SSUEDJUL1998Issued 1998-07Accessory Drive Tensioner Test Standards(Mechanical Rotary Type)1. ScopeTo document test procedures and set-ups that address known failure modes for mechanical rotarytensioners and establish minimum acceptance criteria. This SAE Standard does not encompass the pulley orpull
5、ey bearing. The sample sizes should be determined by agreement between the original equipmentmanufacturer (OEM) and the supplier.The failure modes to be addressed are:a. DurabilityCorrosion ContaminationStructural WearTemperature Alignmentb. FunctionalClamp Load DampingDrop (Safety) Lift LugsLoad No
6、iseOzone Snap2. References2.1 Applicable PublicationsThe following publications form a part of the specification to the extent specifiedherein. Unless otherwise indicated, the latest revision of SAE publications shall apply.2.1.1 SAE PUBLICATIONAvailable from SAE, 400 Commonwealth Drive, Warrendale,
7、 PA 15096-0001.SAEJ2198GlossaryAutomatic Belt Tensioner (Measuring techniques for the acceptance criteria canbe found in this paper.)2.1.2 ASTM PUBLICATIONSAvailable from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.ASTM B 117-95Method of Salt Spray (Fog) TestingASTMD1149-91Test Met
8、hod for Rubber DeteriorationSurface Ozone Cracking in a Chamber (FlatSpecimens)COPYRIGHT Society of Automotive Engineers, Inc.Licensed by Information Handling ServicesSAE J2436 Issued JUL1998-2-3. GeneralTable 1 is based on a 100 mm arm length and is a general guideline for setting test parameters.
9、It isfor reference only since there are many factors that affect amplitude and frequency and should be specified bythe OEM depending on the application. Peak-to-Peak refers to complete arm travel as measured at the pulleycenter. The frequency in the table refers to the drive excitation.FIGURE 1BELT
10、DRIVEN TEST CHAMBERFigure 1 is an example of a belt driven test chamber. One of the pulleys must be eccentric to obtain the desiredpeak-to-peak arm travel of the tensioner. The production intent belt material should be used if possible. Thistest chamber is used for the cold test and the contaminatio
11、n test. It is more likely that the belt driven testchamber will seize the tensioner than the cable driven test chamber.TABLE 1GENERAL GUIDELINESDamping Engine Application4 cylinder engine ApplicationFrequency 25 Hz5% 8 mm peak-to-peak10% 6 mm peak-to-peak20% 4 mm peak-to-peak40% 2 mm peak-to-peak6 c
12、ylinder engine ApplicationFrequency 30 Hz5% 6 mm peak-to-peak10% 5 mm peak-to-peak20% 2.5 mm peak-to-peak40% 1.5 mm peak-to-peak8 cylinder engine ApplicationFrequency 40 Hz5% 4 mm peak-to-peak10% 1.5 mm peak-to-peak20% 1 mm peak-to-peak40% 0.5 mm peak-to-peakCOPYRIGHT Society of Automotive Engineers
13、, Inc.Licensed by Information Handling ServicesSAE J2436 Issued JUL1998-3-Figure 2 is an example of a cable driven test chamber. The center pulley is eccentric to obtain peak-to-peakarm travel. The specified cable diameter is 6 mm. This chamber is used for the corrosion test and the hot boxtest. Thi
14、s configuration is used to test durability by accelerating wear. This test stand must be capable ofrunning at elevated temperatures.FIGURE 2CABLE DRIVEN TEST CHAMBER4. Contamination Test4.1 PurposeTo evaluate tensioner lock up and durability by exposing the tensioner to a contaminatedenvironment and
15、 to determine the effects on the damping rate over the range of the test. The components tobe evaluated are the bushing, damping elements, the spring, and any parts subject to contamination. It is alsopossible to gain some preliminary knowledge of the sealing of the bearing if the production intent
16、pulley,bearing, and dust shield are used.4.2 EquipmentThe test stand is an environmental chamber capable of operating at 70 C 2 C. Thetensioners are to be installed in vehicle nominal position (to obtain correct hub load and gravity bias direction).The tensioners are to be actuated by a belt drive a
17、ttached to an eccentric pulley, as shown in Figure 1. Thebelt should be production intent material. A squeeze bottle with a 1.8 mm nozzle should be used to apply thesolution to the tensioner.4.2.1 CONTAMINATION SOLUTION:a. 3.8 L Waterb. 0.14 kg SAE Course Test dustc. 0.14 kg #400 grit aluminum Oxide
18、 Graind. 0.05 kg #150 grit aluminum Oxide Graine. 0.14 kg Table saltf. 0.005 L Red food coloring4.3 ProcedureActuate the tensioners based on the application (see Table 1) in the test chamber at 70 C 2 Cfor 24 h with no contamination to run in the belt and tensioner. Reset the amplitude to the origin
19、aldisplacement with the tensioner hot. Begin the test by actuating the tensioners in the test chamber at70C2C. Mix the previous ingredients into a solution and spray the tensioner in the 12, 3, 6, and 9 Oclockpositions parallel to the mounting face and directly at the center of the front. Apply the
20、solution for 2 s in eachposition completely wetting the tensioner 3 times a day. This test is to be run for 400 h with data collected at0h, 1 h 200 h, and 400 h.COPYRIGHT Society of Automotive Engineers, Inc.Licensed by Information Handling ServicesSAE J2436 Issued JUL1998-4-4.4 Acceptance CriteriaT
21、he components must remain functional at the end of test.a. The noise level cannot degrade throughout the duration of the test.b. Parallelism should not change more than 0.5 degree.c. The offset change should be no more than 0.80 mm.d. The change in spring load should not be more than 15%.e. The damp
22、ing must remain within the minimum and maximum design envelope established byapplication design parameters.NOTEFunctional measurements of alignment and offset should be made at in vehicle geometry nominalposition. If the damping changes and falls outside of the design specifications, the OEM maychoo
23、se to continue the test at a higher amplitude to induce bushing failure which would be asecondary failure.5. Corrosion Test5.1 PurposeTo evaluate tensioner functional performance and durability by exposing the tensioner to a corrosiveenvironment and determine the effects on the damping rate over the
24、 range of the test. The components to beevaluated are the bushing, damping elements, the spring and any parts subject to wear and/or corrosion.5.2 EquipmentThe test stand is an environmental chamber capable of introducing and maintaining a salt fog asper ASTM B117-95 standard. The tensioners are act
25、uated by cables attached to an eccentric pulley as shownin Figure 2.5.3 ProcedureActuate the tensioners based on the application (see Table 1) in the test chamber at roomtemperature. Follow ASTM B 117-95. Run for 72 h, then turn off the salt spray and the tensioner actuation.Open the chamber and let
26、 it sit for 24 h. Close the chamber and start the salt spray and the tensioneractuation. Visually inspect the tensioner movement. Run for 96 h, then turn off the salt spray and the tensioneractuation. Open the chamber and let it sit for 24 h. Close the chamber and start the salt spray and thetension
27、er actuation. Visually inspect the tensioner movement. Run for 72 h, then turn off the salt spray and thetensioner actuation. Open the chamber and let the tensioners dry for 24 h before checking for function. Thetest time with the salt spray and tensioner actuation is 240 h. The total test time is 3
28、12 h.Every 24 h visually inspect and check for audible noise of the components. Audit the function of thecomponents at 0 h and end of test. Do not open the test chamber more than once a day.5.4 Acceptance CriteriaThe components must remain functional at the end of test. a. The noise level cannot deg
29、rade throughout the duration of the test.b. Parallelism should not change more than 0.5 degree.c. The offset change should be no more than 0.80 mm.d. The change in spring load should not be more than 15%.e. The damping must remain within the minimum and maximum design envelope established byapplicat
30、ion design parameters.NOTEFunctional measurements of alignment and offset should be made at in vehicle geometry nominalposition. If the damping changes and falls outside of the design specifications, the OEM maychoose to continue the test at a higher amplitude to induce bushing failure which would b
31、e asecondary failure.COPYRIGHT Society of Automotive Engineers, Inc.Licensed by Information Handling ServicesSAE J2436 Issued JUL1998-5-6. Hot/Cold Cycling Test6.1 PurposeTo evaluate tensioner functional performance and durability by inducing wear on the componentsand to determine the effects of hea
32、t on the damping rate over the range of the test. The components to beevaluated are the bushing, damping elements, the spring, and any plastic parts.6.2 Equipment6.2.1 EQUIPMENT HOT CYCLEThe test stand for the hot cycle is an environmental chamber capable ofmaintaining a minimum of 100 C 2 C. The te
33、nsioners are actuated by cables attached to an eccentricpulley as shown in Figure 2. 6.2.2 EQUIPMENT COLD CYCLEThe test stand for the cold cycle must be capable of maintaining 40 C 2 C.The tensioners are actuated by a belt as shown in Figure 1 with the tensioner installed in vehicle positionincludin
34、g belt wrap angle. The belt should be production intent material.6.3 ProcedureActuate the tensioners based on the application in the test chamber at 100 C 2 C for 1 h.Soak in cold box at 40 C 2 C for a minimum of 1 h. Cycle for 5 min with an acceleration rate of 100 rpm inthe first 2 seconds, 750 rp
35、m within 7 s, and the correct amplitude and frequency within 10 s. Return to hot boxand run tensioners at 100 C 2 C for 100 h. Soak in cold box at 40 C 2 C for a minimum of 1 h. Cyclefor 5 min with an acceleration rate of 100 rpm in the first 2 s, 750 rpm within 7 s, and the correct amplitude andfre
36、quency within 10 s. Return to hot box and run tensioners at 100 C 2 C for 100 h. Soak in cold box at40 C 2 C for a minimum of 1 h. Cycle for 5 min with an acceleration rate of 100 rpm in the first 2 s,750rpm within 7 s, and the correct amplitude and frequency within 10 s. Total test time 201 h and 1
37、5 min.Every 24 h inspect visually and check for audible noise of the components. Audit the function of thecomponents at 0 h, 1 h, and end of test.6.4 Acceptance CriteriaThe components must remain functional at the end of test. a. The noise level cannot degrade throughout the duration of the test.b.
38、Parallelism should not change more than 0.5 degree.c. The offset change should be no more than 0.80 mm.d. The change in spring load should not be more than 15%.e. The damping must remain within the minimum and maximum design envelope established byapplication design parameters.NOTEFunctional measure
39、ments of alignment and offset should be made at in vehicle geometry nominalposition. If the damping changes and falls outside of the design specifications, the OEM maychoose to continue the test at a higher amplitude to induce bushing failure which would be asecondary failure.7. Cold Box TestElimina
40、ted as a stand alone test. This test is to be run if the Hot/Cold Cycling Test was notpassed. This will help identify if the failure was due to cold temperature.7.1 PurposeTo evaluate tensioner functional performance and durability by inducing wear on the components.Determine the effects of cold on
41、the damping rate over the range of the test. The components to be evaluatedare the bushing, damping elements, the spring, and any plastic parts.7.2 EquipmentThe test stand must be capable of maintaining 40 C 2 C. The tensioners are actuated by abelt with the tensioner installed in vehicle position i
42、ncluding belt wrap angle. The test chamber is shown inFigure 1.COPYRIGHT Society of Automotive Engineers, Inc.Licensed by Information Handling ServicesSAE J2436 Issued JUL1998-6-7.3 ProcedureActuate the tensioners based on the application in the test chamber at 100 C 2 C for 1 h.Soak in cold box at
43、40 C 2 C for a minimum of 1 h. Cycle for 5 min with an acceleration rate of 100 rpm inthe first 2 s, 750 rpm within 7 s, and the correct amplitude and frequency within 10 s. Repeat the cold soak and5 min cycle 3 times.After each run inspect visually and check for audible noise of the components. Aud
44、it the function of thecomponents at 0 h, 1 h, and end of test.7.4 Acceptance CriteriaThe components must remain functional at the end of test. a. The noise level cannot degrade throughout the duration of the test.b. Parallelism should not change more than 0.5 degree.c. The offset change should be no
45、 more than 0.80 mm.d. The change in spring load should not be more than 15%.e. The damping must remain within the minimum and maximum design envelope established byapplication design parameters.NOTEFunctional measurements of alignment and offset should be made at in vehicle geometry nominalposition.
46、 If the damping changes and falls outside of the design specifications, the OEM maychoose to continue the test at a higher amplitude to induce bushing failure which would be asecondary failure.8. Hot Box TestEliminated as a stand alone test. This test is to be run if the Hot/Cold Cycling Test was no
47、tpassed. This will help identify if the failure was due to elevated temperature.8.1 PurposeTo evaluate tensioner functional performance and durability by inducing wear on the components.Determine the effects of heat on the damping rate over the range of the test. The components to be evaluatedare th
48、e bushing, damping elements, the spring, and any plastic parts.8.2 EquipmentThe test stand is an environmental chamber capable of maintaining a minimum of 100 C 2 C.The tensioners are actuated by cables attached to an eccentric pulley. The test chamber is shown in Figure 1.8.3 ProcedureActuate the t
49、ensioners based on the application and Table 1 in a test chamber shown in Figure 1at 100 C 2 C for a minimum of 200 h. Every 24 h inspect visually and check for no audible noise of thecomponents. Audit the function of the components at 0 h, 1 h, and 200 h.8.4 Acceptance CriteriaThe components must remain functional at the end of test. a. The noise level cannot degrade throughout the duration of the test.b. Parallelism should not change more than 0.5 degree.c. The offset change sh
