1、SAE ARP*LiOLLi 88 8357340 0027626 7 B The Engineering Society AEROSPACE =For Advancing Mobility Land Sea Air and Space RECOMMENDED PRACTICE 400 COMMONWEALTH DRIVE, WARRENDALE, PA 15096 y- 3 3 - L3 ARP40 14 Issued 8-31-88 I I Submitted for recognition as an American National Standard I AIRCRAFT TURBI
2、NE ENGINE PNEUMATIC COMPONENT CONTAMINATED AIR ENDURANCE TEST TABLE OF CONTENTS Page No. 1. SCOPE AND PURPOSE . 2 2. APPLICABLE DOCUMENTS 2 3. TEST SETUP I 2 4. TEST CIRCUIT 4 I 5. TEST METHOD . 6 6. TEST DATA . 7 7. LESSONS LEARNED . 8 I LIST OF ILLUSTRATIONS Contaminated Air Test Facility . Figure
3、 1 I 3 SAETechnical 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,
4、is the sole responsibility of the user.” CAE 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 1988 Society of Automotive Engineers, Inc. Printed in U.S.A. All rights reserve
5、d. COPYRIGHT SAE International (Society of Automotive Engineers, Inc)Licensed by Information Handling ServicesSAE ARP*:L1OL:L1 88 = 83573qO 0027b27 9 = ARP40 14 EIE -QB Page 2 1 . SCOPE. AND PURPOSE : This recommended practice describes a method of conducting an endurance test using contaminated air
6、 when the applicable specification requires non-recirculation of the contaminants. determine the resistance of the engine mounted components to wear or damage caused by the contaminated air. The objective of the test is to The method described herein calls for non-recirculation of the contaminants a
7、nd is intended to provide a uniform distribution of the contaminant at the inlet to the Unit Under Test (UUT). The UUT may require the use of a hydraulic fluid for actuation of components within the test unit. Contamination of this test fluid is not part of this recommended practice, however, if req
8、uired by applicable test specification, refer to MAP 749A. 2, APPLICABLE DOCUMENTS : 2.1 blilitary Specifications: MIL-E-5007 - Engine, Aircraft, Turbojet and Turbofan, General Specification for 2,2 SAE Publications: MAP749A - Aircraft & Turbine Engine Fuel System Component Endurance Test (Contamina
9、ted Fuel) 3, 3, TEST SETUP (Ref. Fig. 1): Air Contamination: The air contamination requirements should be as specified in the applicable specification. Typical military requirements for pneumatic components are given in MIL-E-5007. 3,2 Test Fluid: Fluid, if required, should conform to the applicable
10、 specification. The engine primary fuel is recommended, however, if the test facility cannot be safely operated using fuel at high temperature, then the use of a silicone fluid having a specific gravity or viscosity, or both, similar to the engine fluid is recommended. 3.3 Test Fluid.Temperature: Co
11、ntrol is required as necessary to keep the UUT within its operational limits. 3.4 Test Fluid Pressure: The test fluid pressure should be as specified by the applicable test specification. 3.5 Ambient Temperature: Control required as necessary to keep the UUT within its operational limits. Test equip
12、ment used in a hot ambient facility may require special cooling provisions. - - 3.6 Inlet Air Temperature: The air temperature at the inlet of the UUT should be a minimum of 220OF or as otherwise specified by the applicable specification. COPYRIGHT SAE International (Society of Automotive Engineers,
13、 Inc)Licensed by Information Handling Services SAE ARP*4OL4 88 W 8357340 0027628 O W Page 3 L - ARP4014 w FIGURE 1 - Contaminated Air Test Facility COPYRIGHT SAE International (Society of Automotive Engineers, Inc)Licensed by Information Handling Services _I_ - _-I_- SAE ARP*40L4 88 - 8357340 0027b2
14、7 2 - ARP40 14 Page 4 3.7 Inlet Air Pressure: The air pressure at the inlet of the UUT should be a minlmum of 15 psig or as otherwise specified by the applicable specification. 3.8 blounting: Each component should be mounted by its normal mounting pad for a level flight attitude. 3.9 Plumbing: Actua
15、l installation plumbing should be used when possible for connection of test components if two or more components are tested together. Where actual installation plumbing is not available, line sizes, lengths and bends should be duplicated as closely as possible. The matchup of the inlet air line and
16、the opening in the test unit (if not identical to the engine installation) shall be made to prevent contamination in the inlet air from collecting at this interface outside the UUT. 3.10 Facility Filters: A clean-up filter downstream of the facilitys backpressure control valve should be used if ther
17、e is a concern relative to exhausting contaminated air. This filter can be a cotton sateen dust bag sized for the exhaust line. 3.11 Functional Cycling Simulation: The cyclic variations in air flow rate can be accomplished by us-tng a cycle scheduler. Commercial units are available that can be progr
18、ammed to provide switch closures at various time intervals. With proper interface equipment, this scheduler would open and close valves in the test unit in addition to opening and closing a solenoid-operated rig bypass valve, in the opposite sense, so that the air flow rate through the facility rema
19、ins essentially constant. If an automatic cycler is used, consideration should also be given to incorporating an auto-abort system to prevent inadvertent damage to the UUT or test facility. 3.12 Termination f Test: The test should be terminated at a point where the engine system components have been
20、 operated as required under the applicable specification. These components should be functionally tested using the specified clean air after the completion of the contamination test requirements. 4. TEST CIRCUIT: 4,l Circuit Schematic: A typica “ 4.2 Circuit Components: system arrangement is shown i
21、n Fig, 1. 4.2.1 Location: The functional ocation of the circuit components should be as shown in Fig. 1. The locations of the contamination inputs to the inlet line shall be downstream of the UUT Bypass Valve, so that none of the contamination is dumped overboard. The flow rate in the inlet line mus
22、t be sufficient to avoid settling of sol id contaminants and resultant “slugging.“ COPYRIGHT SAE International (Society of Automotive Engineers, Inc)Licensed by Information Handling ServicesPage 5 s= I ARP4014 4.2.1 4.2.2 4.2.3 4.2,4 (Conti nued) : The physical location of the circuit components wil
23、l depend greatly on the facility configuration and the temperature of the air being used, for example, whether or not the UUT is in a hazardous environment relative to human safety. The contamination inputs to the inlet line should be as close to the UUT as possible, that is, less than 24 in, to red
24、uce the amount of contamination that could collect on the wall of the inlet line. The inlet line should have a good electrical ground to prevent a build-up of static electricity which could cause contamination to collect in this 1 ine. Contamination - Liquid contaminants, oil and salt water, may be
25、contained in separate reservoirs and pressurized with a regulated supply of shop air. At the outlet of these reservoirs, a microvalve can be used to set the flow rate for each liquid (drops per minute) and this rate continuously supplied to the inlet air during the test. A length of 1/8 to 1/4 in di
26、ameter tubing, with a 90 deg gradual bend, is recommended for supplying the liqui contaminates coaxial and near the center of the inlet air stream. A ball valve or salenaid valve should be installed between the microvalve and inlet line to shut off these liquid contaminants during facility shutdown.
27、 reservoir to use as an extra check that the proper flow rate is being app 1 ied . The standpipe for introduction of the solid contaminant (sand and road dust) must be located in an operator-safe area,. so that measured amounts of contaminant can be added at specific intervals during the test. The l
28、ength of line between the UUT inlet pipe and standpipe downstream valve is not critical. tubing, and contain no fittings which can trap the solid contaminants. Dew Point Hygrometer: The water vapor in the inlet air can be measured using a Dew Point Hygrometer. The sehsor can be mounted within a few
29、feet of th inlet line so long as it is maintained within its operating temperature limits. The display unit should be located in the operators control console. The bleed-off air line for the sensor should be located upstream of all contamination inputs to the inlet air line to prevent erroneous read
30、ings. It is recommended to put a Tiquid level gauge on each This line should be a straight piece of smooth l.D Hydraulic Cart: to the UUT with actual (or simulated) engine plumb.ing lines. If a hydraulic supply is required, it should be connected 4.3 Instrumentatiorr Calibration: In absence of compa
31、ny standards on calibration schedules, the instrumentation used should be calibrated within a 30-day period prior to starting the test and again within a 30-day period following complet ion of the test. COPYRIGHT SAE International (Society of Automotive Engineers, Inc)Licensed by Information Handlin
32、g Services- _P SAE ARP*40111 88 W 8357340 0027b31 O W SM Page 6 I ARP401 4 5. TEST METHOD: 5.1 Test Preparation: Each facility system should be adjusted and tested for proper operation prior to starting the test. The regulated air supply to the liquid reservoirs and the microvalves should be adjuste
33、d to establish the specified flow rate with the microvalves submitted to actual system backpres s Ure, The pressure and time required to blow the solid contaminants into the inlet air line can be tested without this line being connected, but with proper backpressure, to verify proper operation of th
34、e system. The cycle scheduler, UUT and hydraulic cart should be set up using clean air and run for at least a 1 h trial period prior to introducing any contamination. 5.2 Test: 5.2,l - The test system should be started and advanced to the first test condition as required by the duty cycle at a rate
35、as required by the applicable specification. 5.2.2 Upon reaching the first test conditions, the contamination should be introduced. The bal 1 val ves permitting the 1 i quid contamination to enter the system should be fully opened allowing the liquids to drip into the inlet line at the preset rate e
36、stablished by settings of the microvalves and regulated air supply. be as close as possible to the microvalves. The first charge of solid contamination should be blown into the system during the first cycle. To avoid trapping contaminant, the ball valves should 5.2.3 Repeated applications of solid c
37、ontamination into the system should be applied as required by the applicable specification. 5.2.4 The flow rate of the liquid contamination into the system should be monitored, recorded, and trimmed i.f necessary, no less than four times during the test at time intervals when it is planned to consum
38、e 20, 40, 60 and 80% of the total liquid contamination. 5.2.5 Recordings shoul d be made to insure component compl iance with the appl icabl e speci fica ti on, 5.2.6. The test shall continue for the time or cycles specified in the applicable speci fi cati on I 5.2.7 The contamination system should
39、be shut down within a 1-min time period and the air flow to the UUT bypassed within the next 1-min period in event of a malfunction or scheduled shutdown period. 5.2,8 If shutdown/bypass periods are part of the applicable specification, the enti re system should remain undisturbed during these shutd
40、own periods, 5.2.9 If a complete facility shutdown is required, system maintenance may be performed after the shutdown so long as the UUT is not disturbed. COPYRIGHT SAE International (Society of Automotive Engineers, Inc)Licensed by Information Handling ServicesSAE ARP*L(OLL( 88 8357340 0027b32 2 E
41、 Page 7 ARP402 4 5.2.10 Repeat 5.2.1 through 5.2.9 until completion of the required number of test hours or cycl es. 6. TEST DATA: 6.1 Pre-Test Data: i s usual ly prepared. Prior to the start of an endurance test, a detailed test plan Typical information suppl ied in the test pl an i ncl udes : 6.1.
42、1 Requirements of pre-test and- post-test inspections of the test components. 6.1.2 A detailed test schematic showing all major components and associated pl umbi ng/el ectrical connections. 6.1.3 Component installation instructions. 6.1.4 Contamination and cycling requirements. 6.1.5 Pre-test, durin
43、g test and post-test performance tests to be run. 6.1.6 A sample log sheet showing data to be recorded during the endurance test. 6.2 Endurance Test Data: The following list is an example of recorded data that may. be required, if applicable. A. B. C. D. E. F. G. H. I. J. Date and time of day. Total
44、 operati ng time. Total number of cycles. Ram air pressure, orifice del ta pressure and temperature. Dew point reading. Contami nation added/used at requi red interval s. Hydraul i c supply and drai n pressures. Air temperature and pressure at inlet of UUT and delta pressure across UUT. Performance
45、checks made on UUT during endurance test. Photographs of test faci 1 i ty. 6.3 Post-Test Data: At the completion of the endurance test, the inspections and performance test data outlined in the Test Plan shall be run in addition to additional supporting data required to understand any anomal ies tha
46、t occurred during the test. Photographs and addi ti onal i nspecti ns requi red to def i ne the condition of the test hardware may also be included. Having documented the post-test condition of the UUT, the test item could be cleaned and retested to determine if this restores performance to pre-test
47、 values. 6.4 Test Record: The test record should be a test report containing the initial Test Plan, Inspection Reports, Recorded Test Data, together with an appropriate report narrative stating the Objective, Test Results, Conclusions, Recommendations and Discussion. COPYRIGHT SAE International (Soc
48、iety of Automotive Engineers, Inc)Licensed by Information Handling ServicesI ARP401 4 Page 8 7, LESSONS LEARNED: Some mi 1 i tary specifications requi re that the ai r be saturated with water vapor at 52Y (126F) at an ambient pressure of 29.92 inches Hg. One method for achieving this is by adding en
49、ough saturated steam to obtain this condition. It is not necessary to measure the amount of steam to be added if a Dew Point Hygrometer is used for measuring the dew point of the final air/steam mixture. This is done by bleeding off a small amount of the mixture, passing it through a transducer and exhausting it to the ambient atmosphere. This sensor must be kept above 52C and less than its upper limit of 100C. It is recommended that the transducer for the Dew Point Hygrometer be located far enough removed from the inlet line to maintain it within its operat
