1、- A-A-5 05 7 7 9999974 OL73bb4 551 H INCH-POUND A-A-50577 Januarv 17. 1997 SUPERSEDING 25 July 1991 MIL-S-286 1 1D COMMERCIAL ITEM DESCRIPTION SEMITRAILERS, REAR DUMP; SINGLE AXLE AND TANDEM AXLE The General Services Administration has authorized the use of this commercial item description for ail F
2、ederal agencies. 1, SCOPE. This specification covers single axle and tandem axle rear dump semitrailers. 2. CLASSIFICATION. Semitrailers are of the following types, as specified (see 7.2). Type I Type II Type III Type IV - - - - Single axle, 12-ton (10 886 kilograms (kg) payload capacity, loose mate
3、rial. Tandem axle, 20-ton (18 144 kg) payload capacity, sand and gravel. Tandem axle, 34-cubic yard (26 cubic metre (m3) capacity, demolition. Tandem axle, 30-cubic yard (23 m) capacity, U-shaped dump body. 3. SALIENT CHARACTERTSTICS. 3.1 Design. 3.1.1 Federal Motor Vehicle Safety Standards. The sem
4、itrailer shall comply with DOT Federal Motor Vehicle Safety Standards in effect at time of manufacture. 3.1.2 Curb weight. The curb weight shall include the weight of the semitrailer in operating condition with all attachments, equipment, and accessories. Beneficial comments, recommendations, additi
5、ons, deletions, clarifications, etc. and any data which may improve this document should be sent to: Commanding Officer (Code 1581), Naval Construction Battalion Center, 1000 23rd Avenue, Port Hueneme, CA 93043-4301, by using the Standardization Document Improvement Proposal D Form 1426) appearing a
6、t the end of this document or by letter. AMSC N/A FSC 2330 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-50577 9999974 OL73bb5 498 TYPE IiI 50 o00 (22 680 kg) 34
7、(26 m3) 372 (9 449 mm) 96 (2 438 mm) 60 (i 524 mm) 84 (2 134 mm) 336 (8 534 mm) 9.5 (241 mm) 12 (305 mm) A-A-505 77 TYPE IV 360 (9 144 mm) 96 (2 438 mm) 48 (1 219 mm) 80 (2 032 mm) 350 (8 890 mm) 9.5 (241 mm) 12 (305 mm) 3.1.3 Gross weight. The rated gross weight shall include the curb weight and th
8、e specified payload required in table I, eveniy distributed over the dump body area. Established component and vehicular ratings and capacities shall not be increased to meet the requirements of this specification. Payload (min) (pounds (Ib.) (kg) Cubic yard capacity (min) Overall length of semitrai
9、ler (inches (in). maximum (may) Overall width of semitrailer (in. mu) (mm. mu) Height of body sides. interior (in. +l. -0) (mm. +25.4, -O) Body width, interior (min) Body length. interior (in. +18. -0) (mm. +457, -0) Ground clearance (in. min) (mm. min) Ground clearance under landing gear assembly i
10、n retracted position (in, min) (mm. min) Landing wheel clearance, 6 inches (152 mm) below centerline of the kingpin, measured rearward, without any interference (in. min) (mm min) Kingpin location, measured rearward from front of the semitrailer (in, 16) (mm. f152) Height of upper fifth wheel plate
11、(in, Il) (mm. 25.4) 3.1.4 Dimensions. Semitrailer dimensions shall be as specified in table I, when the floor of the semitrailer body is in travel position on level ground, without payload. 24 O00 40 O00 (10 886 kg) 408 446 (10 363 mm) 96 96 (2 438 mm) 52 24 (1 321 mm) (610 mm) 88 88 (2 235 mm) 288
12、336 (7 315 mm) 9.5 (241 mm) 14 14 (356 mm) (356 mm) 82 82 (2 083 mm) (18 144 kg) - (11 328 mm) (2 438 mm) (2 235 mm) (8 534 mm) 9.5 (241 mm) (2 083 mm) 30 30 (762 mm) (762 mm) 5 1 51 (1 295 mm) (1 295 mm) TABLE I. Weights and dimensions. 82 (2 083 mm) I TYPE I I TYPEII 82 (2 083 mm) 51 (1 295 mm) 52
13、 (1 321 mm) Swing radius from centerline of kingpin to nearest interference point on the semitrailer (in. min) (mm. min) 60 60 (1 524 mm) (1 524 mm) (762 mm) (762 mm) 60 (1 524 mm) 1 :524mm) 3.2 Performance. The semitrailer, hlly equipped and loaded with specified minimum (min) payload in pounds (Ib
14、s) (kg) (see table i), shall be capable of being towed at speeds as great as 1 O miles per hour (mph) (1 6 kilometre per hour (km/h) over unimproved roads (Le. unpaved, unstabilized road with an undulating surface having occasional chuck holes and exposed rocks), and over reasonably hard uneven terr
15、ain; and being towed at speeds as great as 50 mph (80 km/h) over improved roads (i.e. smooth hard surface). 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- A-A-50577 9999974 O173666 324 A-A-50577 3.2.1 Turning ability. The semitrailer shall be cap
16、able of assuming a 90-degree angle to the coupled towing vehicle without cramping or damage to the semitrailer or the towing vehicle. 3 2.2 Tracking ability. The semitrailer shall conform to the tracking requirements of DOT Federal Motor Carrier Safety Regulations. 3.2.3 Brake performance. The semit
17、railer service brake system shall stop the semitrailer-tractor combination with the semitrailer loaded with specified payload within the stopping distance requirements of DOT Federal Motor Carrier Safety Regulations. 3.3 Chassis comDonents. 3.3.1 Frame. The semitrailer fiame shall be fiil1 length an
18、d the manufacturers standard. 3.3.2 Suspension system. The semitrailer shall be furnished with the manufacturers standard suspension system. Each component of the suspension system shall have a rated capacity at least equal to the load imposed, measured at the ground, when the semitrailer is loaded
19、with its rated payload. Clearance shall preclude interference between tires and any other part of the semitrailer under the operating conditions specified herein. 3.3.3 Axle(s). Type I semitrailer shall be furnished with a single axle. Types II, III, and IV semitrailer shall be furnished with tandem
20、 axles. Axle ratings shall be at least equal to the load imposed on each axle, measured at the ground, with semitrailer loaded with rated payload. The wheel bearings and axle spindles shall be oil lubricated. The oil viscosity shaii be in accordance with the manufacturers recommendations. The hubcap
21、s shall have a window for visual determination of oil level. Provision for venting, or other method of withstanding internal pressure buildup, and for replenishing the oil supply shall be incorporated. 3.3.4 Wheels and tires. Semitrailer shall be equipped with dual disk type wheels on each axle. Tir
22、es shall be steel belted radial tubeless type with highway tread. The wheel and tire ratings shall conform to TRA recommendations for the type and size of tires furnished. Tire and wheel sizes shall be the same for all wheels of the semitrailer. Tires shall be rated capacity at least equal to the lo
23、ad imposed on each tire, measured at each wheel at the ground, with semitrailer loaded with rated payload. 3.3.5 Tire camer. One tire camer shall be provided and installed in a readily accessible location under the chassis. Means shall be provided for securing a spare wheel and tire assembly within
24、the carrier to prevent accidental loss. When specified (see 7.2), a spare wheel and tire shall be mounted on the tire camer. The wheel will have an inflated tire mounted on it. The tire will be of the same size and tread design and of the same ply rating as tires installed on the semitrailer. 3.3.6
25、Brakes. Brakes shall be of the full air operated, internal expanding type and shall conform to DOT Federal Motor Carrier Safety Regulations and as specified herein. The braking system shall include manual or automatic slack adjusters, piping, hose connections, gladhands, spring loaded dust covers or
26、 dummy gladhands equipped with security chains, and all other components 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-50577 W 774 OL73bb7 260 A-A-50577 I required for a complete airbrake system. Gladhands shaii conform to SAE J3 18. Air hose
27、 location shall comply with SAE 5702. The braking system shall be installed in a manner which provides road clearance for travel over uneven terrain and protection against damage caused by objects striking components. No part of the braking system shall extend below the bottom of wheel rims. 3.3.6.1
28、 Parking brakes. The semitrailer shall be provided with coil spring actuated type parking brakes. The parking brakes shall be automaticaily applied upon disconnection to the emergency air line and under emergency braking conditions. The parking brakes shall hold the semitrailer, with rated payload,
29、on a 20 percent grade despite the depletion of the compressed air supply. Parking brakes shall conform to DOT Federal Motor Carrier Safety Regulations. 3.3.7 Upper fifth wheel plate. The upper fifth wheel plate shall conform to DOT Federal Motor Carrier Safety Regulations. The kingpin shall be of he
30、at treated alloy steel and shall conform to SAE 5700. The forward end of the upper fifth wheel plate shall have turned-up lip for ease of coupling. 3.3.8 Lighting. The electrical lighting system shall be 12-volt (V) direct current (dc) design. The lighting system shall conform to DOT Federal Motor C
31、amer Safety Regulations. Ail lights and reflectors shall be protected from operational hazards by mounting in recessed or otherwise guarded locations. Lights and reflectors shall not be mounted on vertical surfaces of the rub rails, unless recessed and fully protected, or semitrailer bumpers. The fr
32、ont of the semitrailer shall be equipped with a receptacle conforming to SAE J560, with the receptacle located and the conductors connected and color coded as specified herein. Ail electrical wiring shall conform to SAE 51292. Turn signal lamps shall conform to SAE J588. 3.3.9 Landing gear. Semitrai
33、ler shall have two vertical lift, telescopic, nonrotating landing legs, with two speed gears and a handcrank on the curbside. Landing legs shaU be equipped with steel wheels or self-leveling skid pads. Supports for the crank extension shafts and clips for holding cranks when folded shall be provided
34、. The landing gear shall withstand, without deformation, the combined static and dynamic forces due to proportion of gross weight sustained and the forces resulting fiom impact during coupling and uncoupling operations. The landing gear shall have a range of adjustment to vary the height of the uppe
35、r fifth wheel plate, at centeriine of kingpin, fiom 45 inches (i 143 millimetre (mm) to not less than 53 inches (1 346 mm) to permit the tailgate, hinging at the top, to have a choice of openings at the bottom for spreading of aggregate; and to allow the tailgate, hinging at the bottom, to be laid f
36、lat with the floor of the body. Unless otherwise specified (see 7.2), the tailgate shall be opened at the bottom by a driver-actuated, tailgate-trip control installed on the left front of the body. Release of the tailgate for dumping a heaped load shall not require driver effort in excess of 60 poun
37、ds (27 kg) at the control. Air controls, when fiimished, shall be protected from falling aggregate. 3.4.1.2 Tailgate, type III. The type III tailgate shall be of the side-hinged, barn door type with outside latches. The tailgate shall be reinforced with vertical and horizontal high strength structur
38、ai members. 3.4.1.3 Tarpaulin. When specified (see 7.2). a tarpaulin of sufficient size to cover the top of the body with overlap on the sides shall be furnished. The tarpaulin shall be 16-ounce (0.45 kg) neoprene rubber coated nylon cloth with grommets or tie loops on 24-inch (610 mm) centers. Tarp
39、aulin tiedown rails shall be provided. The required number of rubber tiedown straps with hooks at both ends shall be provided to secure the tarpaulin over the body. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- A-A-50577 M 9999974 0373669 033 9
40、A-A-50577 3.4.1.4 Tarpaulin rack. When tarpaulin is specified (see 3.4.1.3), a tarpaulin storage rack shall be installed on the front of the body. The rack shall be a shelf or basket type and shall be fabricated of metal. A means of storage for the required number of tiedown straps shall be provided
41、. 3.4.2 Hydraulic system. The semitrailer shall be equipped with an engine power source (see 3.4.4), hydraulic body hoist system. The hydraulic system shall be complete with all operating accessories, including pump(s), reservoir, hydraulic cylinders, valves, pressure gages, pressure relief valves,
42、filter, hoses, piping, and fittings. The dump body shall hoist to the dump angle of the manufacturers standard semitrailer. Hydraulic fluid conforming to MIL-H-46170 shall be provided in the hydraulic system. A permanent decal near the filler opening shall be installed with this statement: “CAUTION:
43、 USE HYDRAULIC FLUID CONFORMING TO MIL-H-46170 ONLY.” At least 6.5 inches (165 mm) of clearance shall be provided between exhaust systems. The cylinder rams or telescopic tubes shall be ground and polished. 3.4.2.1 Hoist system. The hoist system shall consist of components rated to perform the hydra
44、ulically powered operations of the dump body in accordance with the specified payload. Mechanisms and reservoirs shall be positioned or guarded to prevent any possible hazard or damage from hot surfaces, debris, or obstructions. The dump hoist control shall be the three-way type, providing hoist, lo
45、wer, and hold. 3.4.2.2 Hoist actuation. The actuation of the body hoist system shall be the self-contained type, whereby the complete hoist system shall be mounted on the semitrailer with an auxiliary engine driving hydraulic pump. The engine and hydraulic pump components shail be mounted on the goo
46、seneck of the semitrailer. 3.4.2.3 Hoist system controls. The hoist system controls shall be mounted on the street side fiont of the semitrailer and adjacent to the engine controls. The controls shall be located to permit operation by the operator fiom a standing position on the ground. 3.4.3 Shroud
47、. Engine shall be provided with a sheet metal shroud, with side panels, to protect the engine when loading the semitrailer and during inclement weather conditions. Panels shall be removable. Louvers shall be provided for air circulation. 3.4.4 Power source, A standard commercial, four-stroke cycle,
48、air-cooled gasoline or diesel engine shall be provided to drive the hydraulic pump assembly. The engine shall be mounted in conjunction with the hydraulic pump. Mounting shall be so as to minimize transfer of vibration. The engine shall have the horsepower, torque, and speed characteristics to meet
49、satisfactorily all performance requirements specified herein. 3.4.4.1 Engine components. The engine shall be equipped with, as a minimum, the following components: a. Ignition system. b. Electric starting system, 12V dc. c. Manufacturers standard air cleaner. 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- A-A-50577 9999974 0373670 855 t A-A-5 05 77 d. Manual choke (gasoline). e. Battery, 12V
