1、MIL-T-26378D 47 W 7779706 0247L77 b = .I MIL-T-26398DUSAF) 7 February i967 SUPERSEDING MIL-T-26398C(USAF) 15 June 1965 MILJTARY SPECIFICATION 1. SCQ.PE TEST STAND, AIRCRAFT HYDRAULIC SYSTEM, TRAILER-MOUNTED, A/M27T-2, ELECTRIC-MOTOR-DRIVEN, TRIPLE SYSTEM 1.1 This specification covers a triple- syste
2、m (each system providing 20 gpm at 3,000 psiand10gpmat5,000psi),electric- motor-driven, trailer-mounted, aircraft hydraulic system test stand, designated A/M2 7 T-2. 2. APPLICABLE DOCUMENTS * 2.1 The following documents, of the issue in effect on date of invitation for bids or -request for proposal,
3、 form a part of this specification to the extent specified herein: SPECIFICATIONS Federal - CC-M-641 Motor, Alternating Cur- rent, (Integral-Horse- power, 200 HP and Smaller) GG-G-76 . Gages, Pressure and Vacuum, Dial Indicating (For Air, Steam, Oil, Water, Ammonia and Chloro-Fluoro Hydro- carbon Ga
4、ses) .PPP-B-621 Box, Wood, Nailed and Lock-Corner PPP-T-60 Tape, Pressure Sensi- tive Adhesive, Water- proof, for Packaging Military MIL-P-116 MIL-B-121 MIL-F-3541 MIL-C-3600 MIL-H-5440 MIL-R-5220 MIL-H-5593 MIL-H-5606 MIL-C-5756 MIL-H-6083 MIL-M-8090 MIL -A -8421 Preservation, Methods of Barr i er
5、Ma ter ial, Greasep roofed , Water - proofed, Flexible Fittings, Lubrication Compressors, Air and Gas (Except Oxygen) Packaging of Hydraulic Systems,Air- craft Types I and II, Design, Installation,and Dah Requirements for Reservoirs, Aircraft, Hydraulic, Non-Sepa- rated Type Hose, Aircraft, Low- Pre
6、ssure, Flexible Hydraulic Fluid, Petro- leum Base, Aircraft, Missile, and Ordnance Cable and Wire, Power, Electric, Portable Hydraulic Fluid, Petro- leum Base, for Preser- vation and Testing Mobility, Towed Aero- space Ground Equip- ment, General Require- ments for Air Transportability Re- quirement
7、s, G e n e r a 1 Specifioation for Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-H-8788 MIL-E-16298 MIL-F -2 7 65 6 MIL-R-3 848 9 STANDARDS Military MIL-STD -1 O0 MIL-STD-105 MIL-STD -129 MIL-STD -130 MIL-STD -1 43 MIL-STD-281 MIL -STD -8 08 MI
8、L-STD-810 MIL-STD-826 MIL-STD -831 Hose, Hydraulic and Pneu- matic, High Pressure Electric Machines Having Rotating Parts and Asso- ciated Repair Parts, Packaging of Filter, Fluid, Pressure, Absolute 5 Micron, Hy- draulic Reels, Static Discharge, Groundin RMU-l7/E and RMu-i while in the other positi
9、on, the reservoir shall be exhausted and the pressure regulating outlet blocked Off. 3.8.6.6 Drain valve. A drain valve shall be provided for draining the reservoir. Necessary clearance shall be provided around the drain outlet to permit rapid draining into l-gallon containers. 3.8.6.7 Access plates
10、. One or more access plates of at least 7 inches diameter or 8 by 6inches in accordance with sta- dard design practices for ASME coded vessels shall be provided to permitvisual inspection and manual cleaning of the in- terior of the reservoir. 3.8.7 Pressure outlets. Three pressure outlets shall be
11、provided as shown on figure 1. Each outlet shall be color-coded to correspond with the color code on the control panel. The outlets shall not be located where leakage of fluid from the outlets could fall on the trailer tires or within the housing. The outlets and dust caps shall conform to Aeroquip
12、part No, 015628-S2-12 and No, 155-S7-12D, re- .spectively, or a part equal to and inter- changeable with the Aeroquip part, . % 3.8.7.1 Pressure connections. Allvalves, connections, and tubing used from the high- pressure pump discharge ports to the ends of the 30-foot pressure hoses shall be of a s
13、ize that will not permit the pressure op to exceed 150 I10 psi with 20 gpm flow. All connections and fittings on the high-pressure side shall be not less than l-inch tubing size. Tubing shall be used on all high-pressure lines within the test stand, except where impractical because of vibration. - M
14、IET-2 63 9 8D (USAF) - . ._ *3.8.8 Return connections. Three return connections shall be provided as shown on figure 1. The outlets shall conform to Aeroquip part No. B145-S2-16D or a part equal to and interchangeable with the Aeroquip part. A dust cap conforming to Aeroquip part No. 145-S7-16D or a
15、part equal to and interchangeable with the Aeroquip part shall be attached to the outlet, Each outlet shall be color-coded to correspond with the color code on the control panel. The outlets shall belocated for convenience. The locations shall not permit leakage from the connections to fall on the t
16、railer tires nor within the test stand housing. 3.8.8.1 Low-pres sure components and connections. The size of all the connec- tions used in the suction side of the hy- draulic system shall be such as to allow not more than a 20-psi drop at 20 gym with fluid temperatures of 60F from the aircraft outl
17、ets through 30 feet of hose to the suction side of the boost pumps, Suction lines and components shall be not less than 1-1/4 inch tubing size and rated no less than 200 psi. 3.8.8.2 External and internal leakage. Total external leakage shall not exceed 2 drops per hour at any flows or pres- sure sp
18、ecified herein. Internal leakage shall not exceed 5 cubic inches per hour from the closed loop system of either system. 3.8.9 Oil coolers. An air-to-oil cooler(s) shall be provided in the systems asshown on figure 1. The oil cooler(s) shall main- tain the oil temperatures of each system below 140F w
19、hen 20 gpm at 750 psig is bypassed through the coolers with an ambient air temperature of 100F. The oil cooler(s) shall permit full flow through the bypass without damage resulting there- from. The oilcooler(s) shall operateunder 11 Provided by IHSNot for ResaleNo reproduction or networking permitte
20、d without license from IHS-,-,- - - MIL-T-2637D 47 7974706 0247230 3 - MIL- T-26398D (USAF) pressures of 200 psi without leakage or damage. The oil cooler(s) shall be pro- vided with a means to make them inoper- exceed 10 drops in 5 minutes. Valve size shall be not less than 3/8 inch tubing size. ab
21、le in low temperatures. 3.8.10 Flow control and bypass valves. Three flow control and three bypass valves of 1 inch size, or larger, shall control or stop the flow into or from each pressure outlet. The valves shall withstand 10 gpm flow and 5,000 psi pressure. They shall accurately meter the flow t
22、hroughout the volume range of O to 20 gpm and shall be pressure balanced so that a force of 40 pound-inches is the maximum required turning force at 3,000 psi. The valves shall, go from the cloBed position to the open position in not more than two full turns of the handle, The valves shall controlth
23、e flow to within *1/4 gprn where flow rates are below 5 gpm, and 11 gpm with flow rates from 5 to 20 gpm. w3.8.11 Fill system. A fill system in- corporating a 3-phase, 440-V electric- motor-driven pump, filter, pushbutton- type fill valves, and relief valves, as shown on figure 1, shall be provided
24、to facilitate adding oil or filling each system as desired. 3.8.11.1 Filling pump. The fillingpump shall be a low-pressure, hydraulic pump having a capacity of at least 2 gpm at 150 psi. The filling pump and motor con- trols shall be in accordance with 3.10.3 and 3.10.4. 3.8.11.2 Filling valves. Thr
25、ee push- button-type valves shall be mounted on the control panel. Force necessary to operate the valves shall not exceed 10 pounds. When in the release position, the valves shall not permit leakage from the aircraft hydraulic system into the reservoir to *,3.8.11.3 Fill system relief valves. Three
26、variable relief valves, as shown on figure 1, shall be provided (but not mounted) on the control panel. The valves shall be adjustable throughout a pressure range of O to 140 psi and capable of re- lieving the total volume discharged by the fill pump. The valves shall have a locking device so that v
27、ibrations cannot change the pressure settings, The relief valves shall be so designed that maximum pres- sure settings will be 140 15 psi (set at 110 psi). 3.8.11.4 system check valve. A check valve shall be located in the fill sys- tem as shown on figure 1 to prevent re- verse flow to the fill syst
28、em pump, * 3.8.11,5 Fill system filter. An AN6235-2A filter element shall ke located in the fill system as shown on figure 1. The filter assembly shall conform to an MS28720-6 filter configuration, except it shall be suitable for 145 psi operating pressure. 3.8.11.6 Fill system connections. All line
29、s, tubing, hoses, and connections used in the fill system shall be 3/8 inch tubing size or larger. 3.8.12 Pressure check valves. Pres- sure check valves that are dimensionally interchangeable with AN6249-16 valves, but suitable for operation at 5,000 psi, shall be located as near the high-pressure p
30、u.mp outlet as practical to prevent re- verse flow to the high-pressure pumps. (See figure 1.) * 3.8.13 Flowmeters. Three flowmeters of the -transparent type, rated at 300 psig operating pressure, and having a range of 12 Provided by IHSNot for ResaleNo reproduction or networking permitted without l
31、icense from IHS-,-,- I i MIL-T-2639D 97 7799906 0247211 3 3 to 30 gpm and an accuracy ofk2 percent of full scale reading shall be provided in . the low-pressure lines as shown on figure 1. A 250-mm minimum length read- able section shall be illuminated for con- tinuous visual inspection of the fluid
32、 for air. The flowmeters shall be easily re- movable for cleaning without affecting calibration. . 3.8.14 High-pressure gages. Flush- mounted temperature-compensated high- pressure gages shall be provided. They shall conform to GGG76, except where conflicts exist the provisions of this speci- ficati
33、on shall govern. 3.8.14.1 The gages shall be constructed of corrosion-resistant materials. They shall have a 6-inch diameter dial and a steel-alloy bourdon tube. The pointers shall be adjustable without removing the gages from the panel. The gages shall withstand operation at -40“ to +350“F. 3.8.14.
34、2 The gages shall provide arange of O to 6,000 psi and shall incorporate a means to restore their accuracy under all service conditions. The gages shall be accurate to within 1/2 percent, or less, of full scale at all temperatures and con- ditions specified herein. 3.8.14.3 The gages shall be of the
35、 recess type provided with a mounting flange at the front of the gage. The mounting flange and dial shall not extend more than 5/8 inch beyond the external surface of the panel. 3.8.14.4 The gages shall incorporate a safety blowout device. The safety blowout device shall automatically relieve the ga
36、ge case pressure should it reach 1/2 psi due to gage failure. 3.8.14.5 Stainless-steel movements shall be provided on all gages. The dial and MIL- T- 26 3 9 8 D( USAF ) pointer shall be separated from the gage movements by a wall that will prevent rupture through the front of the gage in the event o
37、f gage failure. Gages subjected to continuous surges and extreme pres- sure fluctuations shall be protected by a hydraulic dampener. 3.8.14.6 Mounting. All gages shall be mounted by screws and tapped panel holes to permit removal by one man from in front of the panel. 3.8.14.7 Connection. All fluid
38、gages shall be connected with flexible AN- or MS-type hose, or commercial equivalent, of suffi- cient length to permit removal and instal- lation f the gage from the front of the panel. 3.8.14.8 Throttling. All pressure gages shall be equipped with needle valves located as close as practicable to th
39、e gages. 3.8.14.9 Gage lines, The high-pressure gage lines shall be provided with needle shutoff valves, accumulator-type pulsation dampeners, and gage test fittings. 3.8.14.9.1 Shutoff valves. The needle shutoff valves shall be of the Danel- mounted type with corrosion-reiistant steel stems. The va
40、lves shall show the manufacturers cold-working pressure rating stamped on the valve body with an arrow indicating the flow direction. The valves shall withstand working pressures up to 5,000 psi. 3.8.14.9.2 Gage test fittings. The fol- lowing fittings shall be mounted on the control panel as shown o
41、n figure 1. They shall be mounted adjacent to the appro- priate gage. The control panel shall be Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-1 MIL-T-2b398D 49 W 999770b 0247232 5 m .- _ MIL-T-2 6 398D (USAF) marked to indicate that the fittings a
42、re gage test connections. a. An AN832-4D nipple b. An AN924-4D nut c. An AN929-4 cap. * 3.8.15 Low-pressure gages. Flush- -mounted compound gages shall be pro- vided and shall have corrosion-resistant- steel bourdon tubes and dials of 3-1/2 inch diameter or larger. The gages shall be accurate to wit
43、hin 1 percent of full scale range and shall conform to GG-G-76, ex- cept that where conflicts exist, the pro- visions of the specification shall govern. They shall provide a range of 30 inches Hg vacuum to 300 psi. The gage move- ments shall be constructed of stainless steel throughout and shall wit
44、hstand oper- ation from -40 to +250F. In all other re- spects, the gages and mountings shall conform to 3.8.14 through 3.8.14.7 and - 3.8.14.9.2. 3.8.15.1 Gane selector valves, Three shutoff-type selector valves shall be mounted on the instrument panel. They shall permit pressure selection at the .
45、various points as shown on figurel. 3.8.16 Temperature gages. Flush- mounted, remote- reading temperature gages shall be provided, The range of the gages shall be approximately from -20“ to +250“F and shall indicate within *5“F of the temperature of the fluid supply to the high-pressure pumps. The g
46、ages shall have 3-inch diameter dials, or larger, and shall be flush-mounted. The dial faces shall be marked with a red sector as a warning at 160F andhigher. The accuracy of the gages shall not be affected by con- tinued exposure to the climatic extremes specified herein. . 3.8.17 Duplex gage. A du
47、plex gage with a 3-1/2-inch dial face shall be mounted on the test stand panel to simulfheously indicate the pressure of both sides of the filter in the fill system. The duplex gage shall have a range from O to 200 psi.and shall be constructed of corrosion- resistant material throughout. c 3.8.18 Ho
48、rn. A horn shall be provided which will sound a warning signal when either pressure or temperature conditions, or both, are beyond recommendedranges. The horn shall be audible at 25 feet from the test stand when the test stand isoper- ating at full capacity. 3.8.18.1 Thermoswitches. Adjustable and s
49、nap-action-type preset thermo- switches shall be provided to sound the warning horn when the fluid inlet temper- ature to any high-pressure pump exceeds 165F. The thermoswitches shall have an adjustable range of 150“ to 200F. C3.8.18.2 Pressure switches. Pressure switches shall be provided to shutoff each system when the output pressure at the booster pumps falls below normal. 3.8.19 Hose assemblies. The hose as- semblies specified in table I shall be provided with each test stand
