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.Copyright 2004 SAE InternationalAll rights reserved. No part of this publication may be
3、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)Fax: 724
4、-776-0790Email: custsvcsae.orgSAE WEB ADDRESS: http:/www.sae.orgAEROSPACE STANDARDAS4157REV.AIssued 1988-05Revised 1995-07Reaffirmed 2004-05Coupling Assemblies, Hydraulic,Self-Sealing, Quick Disconnect5000 and 8000 Pounds Per Square Inch, Gage1. SCOPE:This specification covers the requirements for a
5、ircraft hydraulic, self-sealing, quick disconnect couplings for use in 5000 and 8000 lbf/in2(gage) lightweight hydraulic systems.1.1 Classification:Hydraulic self-sealing, quick disconnect couplings shall be of the following classes and types:a. Class 5000 - 5000 lbf/in2(gage) Operating Pressure (ps
6、i)b. Class 8000 - 8000 lbf/in2(gage) Operating Pressure2. REFERENCES:2.1 Applicable Documents:The following publications form a part of this specification to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other publications shall be the issue i
7、n effect on the date of the purchase order. In the event of conflict between the text of this specification and references cited herein, the text of this specification takes precedence. Nothing in this specification, however, supersedes applicable laws and regulations unless a specific exemption has
8、 been obtained.2.1.1 SAE Publications: Available from SAE, 400 Commonwealth Drive, Warrendale, PA15096-0001.ARP24 Hydraulic Pressure Drop, Determination ofARP578 Detail Requirements for 4000 and 5000 psi Aircraft Hydraulic SystemsARP603 Impulse Testing of Hydraulic Hose Assemblies, Tubing, and Fitti
9、ngsARP868 Pressure Drop Test for Fuel System ComponentsAIR1047 A Guide for the Selection of Quick Disconnect Couplings for Aerospace Fluid Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS4157 R
10、evision REV. A- 2 -Systems2.1.2 U.S. Government Publications: Available from DODSSP, Subscription Services Desk, Building 4D, 700 Robbins Avenue, Philadelphia, PA 19111-5094.MIL-F-85720 Fittings, Tube, Fluid Systems, Separable, High Pressure Dynamic Beam Seal, General Specification forMIL-G-5514 Gla
11、nd Design, Packings, Hydraulic, General Requirements forMIL-H-8775 Hydraulic System Components, Aircraft there shall be none.4.6.4 Leakage:4.6.4.1 Leakage at Low Pressure: The connected coupling and the disconnected halves shall be subjected to an internal pressure equal to a head of 30 in of hydrau
12、lic fluid for 12 min. All external surfaces shall be dry at the beginning of this test. There shall be no evidence of any external leakage from the connected coupling. A waiting period of 2 min shall be allowed for the leakage rate to become constant from the disconnected halves. Following this wait
13、ing period, leakage shall be measured for the next 10 min and shall not exceed one drop.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS4157 Revision REV. A- 12 -4.6.4.2 Leakage at High Pressur
14、e: Both the connected coupling and the disconnected halves shall be subjected to a hydraulic static pressure equal to the applicable operating pressure, per 1.1, for 15 min. All external surfaces shall be dry at the beginning of this test. There shall be no evidence of any external leakage from the
15、connected coupling. Leakage from the disconnected halves shall not exceed a trace (insufficient to form a drop in 10 min). Fluid loss (spillage), as specified in Table 2, is not considered to be external leakage.4.6.5 Vacuum: A vacuum shall be applied to the connected and disconnected coupling equiv
16、alent to 10 in Hg. When the correct vacuum pressure has been attained, the lines shall be closed for a period of 5 min, during which time there shall be no change in vacuum pressure.4.6.6 Surge Flow: The couplings shall be subjected to surge flows shown in Table 1 for 3 s minimum duration in each di
17、rection. This surge flow pattern shall be repeated 100 times. There shall be no evidence of flow blocking or internal damage, and the disconnected halves shall pass the leakage tests (see 4.6.4) at the completion of the surge flow sequence.4.6.7 Vibration - Sinusoidal: Unless otherwise specified by
18、the procuring agency, the couplings shall withstand the following vibration tests without evidence of failure or leakage. During the vibration test, 15 lbf/in2(gage) pressure shall be applied. The vibration testing is required per MIL-STD-810D. The parameters shall be established in conjunction with
19、 the procuring agency.4.6.7.1 Resonance:4.6.7.1.1 Resonance Search: The connected coupling and disconnected flight half, capped, shall be pressurized to 15 lbf/in2(gage) pressure and a resonance search conducted, in direction parallel and perpendicular to the axis of the coupling (two axes total). R
20、esonant frequencies of the equipment shall be determined by varying the frequency of applied vibration slowly through the range of 5 to 2000 Hz at reduced test levels but with sufficient amplitude to excite the item.4.6.7.1.2 Resonance Dwell: The test item shall be vibrated along each of the two axe
21、s, at the most severe resonant frequencies determined in 4.6.7.1.1. The test levels and frequency range shall be in accordance with Figure 3. The dwell time for each resonance shall be 30 min. If more than four significant resonant frequencies are found for any one axis, the four most severe resonan
22、t frequencies shall be chosen for the dwell test. If a change in the resonant frequency occurs during the test, its time of occurrence shall be recorded and immediately the frequency shall be adjusted to maintain the peak resonance condition. The final resonant frequency shall be recorded.4.6.7.2 Cy
23、cling: The test article shall be vibrated for a total duration of 3 h in each of the two axes. The resonance dwell time per axis shall be subtracted from the 3 h of required cycling time. These levels shall be per Figure 3 and the sweep time shall be 20 min for 5 to 2000 to 5 Hz.4.6.8 Impulse: The m
24、ated coupling (and disconnected coupling halves with pressure cap, if required) shall be subjected to impulse testing in accordance with the general requirements of ARP603. Test conditions shall be per Table 6 in a setup per Figure 1. The impulse test machine shall produce dynamic pressure impulses,
25、 in the coupling, of the magnitude indicated by the trace shown in Figure 4. The form of the electronics trace shall be included in the test report.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE
26、 AS4157 Revision REV. A- 13 -FIGURE 3 - CompositeVibration Test Curve for EquipmentMounted on Helicopters or Airplane EnginesCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS4157 Revision REV. A
27、- 14 -FIGURE 4 - Impulse TestTABLE 6 - Impulse TestClass Class5000 80001. Rated Pressure, Pr 5000 80002. Peak Pressure, 5% 7500 10 8003. Temperature (both classes) at 275 F for 25% of the cycles at 275 F for 25% of the cyclesat 225 F for 75% of the cycles at 225 F for 75% of the cycles4. Cycle Rate,
28、 cycles/min 70 10 70 105. Rate of Rise, lbf/in2per sMin 75 000 120 000Rate of Rise, lbf/in2per sMax 300 000 800 0006. Number of Cycles 250 000 250 000Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-S
29、AE AS4157 Revision REV. A- 15 -4.6.9 Endurance: The couplings shall be subjected to 1000 coupling and uncoupling operations. During each operation, the pressure specified in Table 3 shall be applied to each half of the coupling. The coupling shall be observed for any indication of malfunction, and t
30、he fluid loss plus leakage for this test shall be measured. The coupling shall withstand this test without malfunction or excessive wear and the coupling force at the end of the endurance cycle shall not exceed values in Table 3. The fluid loss shall not exceed the values of Table 2. There shall be
31、no external leakage.4.6.10 Manual Operation:4.6.10.1 Operation: The couplings connect and disconnect operation test shall be performed with one hand, a minimum of five times for each condition stated below, with the static pressure applied per Table 3 herein. Pressure shall be applied to both halves
32、 and each one-half of the coupling respectively (when one-half is pressurized and the other half is unpressurized).The axial force or torque required to connect and lock the two halves shall be measured; the maximum allowed values are specified in Table 3. The fluid loss during the connect/disconnec
33、t operation cycle and leakage at the end of the operational cycles shall not exceed the specified values of Table 2 and 4.6.4.2 respectively. No evidence of malfunction or deterioration in performance shall be allowed.4.6.10.2 Performance: It shall be verified during operation that the performance o
34、f the couplings visual indicator or the visual-and-touch indicator is satisfactory. The coupling shall be observed to insure that, at no time, does it permit a partially coupled condition, thereby restricting the fluid flow. The coupling shall provide a clear indication that the two halves are secur
35、ely locked and the fluid passage fully opened. The compliance to the interchangeability requirement of 3.5 shall also be verified.4.6.11 Air Inclusion: The coupling shall be subject to an air inclusion test to determine compliance with Table 2. This test may be performed during the manual operation
36、test specified in 4.6.10 at 30 in of oil pressure.4.6.12 Impact: Unless otherwise specified by the procuring agency, the connected couplings and disconnected coupling halves (disconnected coupling halves with caps and plugs), if required, shall be subjected to 18 impact shocks of 20 g, three in each
37、 direction along three mutually perpendicular axes, each shock impulse having a time duration of 10 ms 1 ms. The test couplings shall be filled with the test fluid per 4.5.1 at 0 lbf/in2pressure for this test.The intensity shall be within 10%. The maximum g shall be reached in approximately 5 ms. In
38、advertent uncoupling shall not occur for the coupled condition as a result of this test. Evidence of leakage or malfunction after the test is not permitted. Shock pulse confirmation shall be optional. If the impact testing is required per MIL-STD-810D, the procuring agency shall specify the paramete
39、rs to be used.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE AS4157 Revision REV. A- 16 -4.6.13 Pressure Drop: Pressure drop through the connected coupling shall be measured at a flow equal to t
40、he rated flow capacity prescribed in Table 1. The hydraulic fluid flow shall be accurately maintained. A manometer or other equally accurate method (differential pressure gage) of differential pressure measurement shall be connected across the coupling, as shown in Figure 5. The temperature of the f
41、luid shall be maintained at 100 F 10 F.FIGURE 5 - Setup for Pressure Drop Test(See ARP24)The pressure drop in each direction shall not exceed the value specified in Table 1. The pressure drop of the coupling shall be considered as the difference in pressure drop through the coupling and the pressure
42、 drop through the same length of rigid tube and standard straight fittings, if used, of corresponding diameter. As an alternate, the test method and schematic shown in ARP868 can be used.A pressure drop curve shall be supplied as part of the qualification test report covering a flow rate from 50 to
43、150% of the nominal rated flow.At the option of the procuring agency, during the acceptance test, a modified pressure drop and flow rate test can be used to verify that there is no blockage or abnormal flow restriction.Copyright SAE International Provided by IHS under license with SAENot for ResaleN
44、o reproduction or networking permitted without license from IHS-,-,-SAE AS4157 Revision REV. A- 17 -4.6.14 Burst Pressure: The connected coupling and the disconnected halves with their respective pressure cap and plug, if required, shall be subjected to a burst pressure equal to 250% of the operatin
45、g pressure for a minimum of 2 min. The rate of applying pressure shall not exceed 20 000 lbf/in2/min 5000 lbf/in2/min. There shall be no rupture under the specified pressure, and leakage shall not exceed twice the values of 4.6.4. Deformation (insufficient to cause leakage) and binding are permissib
46、le. Coupling and uncoupling need not be verified after burst test. This test shall be conducted at the high temperature listed in 4.6.3.1.4.7 Acceptance Tests:The detail test parameters and extent of the production testing shall be established by the procuring agency.4.7.1 Examination of Product: Vi
47、sually inspect the unit to verify good workmanship and correct markings. Physically measure and record all dimensions noted on applicable assembly drawings to verify correct configuration. Record dry weight on sampling basis. Visually check surface finishes and processes.4.7.2 Proof Pressure: The co
48、upled coupling and uncoupled halves shall be subjected to a proof pressure of 150% of the rated pressure for a period of 1 min at room temperature. There shall be no leakage greater than that specified in 4.7.4, nor any permanent distortion or other malfunctioning of the coupling. The coupling shall
49、 couple and uncouple normally and seal hydraulic fluid as required after having been subjected to this test.4.7.3 Manual Operation: The coupling shall be coupled and uncoupled without the use of tools with the pressure shown in Table 3 applied to both halves. One half shall be securely mounted in a fixed position for this test. The axial force or torque, or both required to couple and lock shall be measu
