MIL-S-62127 Semitrailer, Compressed Gas Cylinder: Helium, CommercialThis specification covers a commercial semitrailer for storing, transporting, and charging compressed helium gas. The tandem axle semitrailer mounts 38 cylinders having a combined water capacity of not less than 340 cubic feet and a design working pressure of at least 2400 pounds per square inch gage psig. Semitrailer procured under this specification are commercial items which shall be warranted as specified in the procurement documents.

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 - 22 - 23 - 24 - 25 - 26 - 27 - 28 - 29

MIL-S-62127A(AT)

3.4.2 Service brakes. The service brakes shall control, decelerate and stop the semitrailer-tractor combination with the semitrailer loaded with specified payload, within the stopping distance requirements of Federal Motor Carrier Safety Regulations 393.45 through

393.52.

* 3.5 Dimensions and clearances. The minimum dimensions and clearances shall be as specified in table I, when measured with the semitrailer uncoupled from the towing vehicle, resting on the landing gear and tires, with the semitrailer horizontal to ground level, and without payload.

TABLE I. Dimensions and clearances.

Feature

Dimension

Overall length (feet) (max.)

Overall width (inches), (plus or minus 1 inch)

Upper fifth wheel height, from ground to underside of the

upper fifth wheel plate (plus 1 inch, minus 0) Distance from centerline of kingpin to front end of the semitrailer (plus 1 inch, minus 2 inches)

Swing radius from centerline of kingpin to most distant

point on the semitrailer nose (not more than) (inches) Landing wheel clearance (radius from centerline of the kingpin to any point 6 inches below the upper fifth wheel plate) (not less than) (inches)

Ground clearance, max. possible but not less than (inches)

34-1/2

3.6 Chassis components.

* 3.6.1 Chassis. Chassis components and vehicle ratings shall be the manufacturer's published ratings. Axle, suspension, wheel and tire ratings shall be for highway speeds

(over 50 mph). Chassis construction shall be the manufacturer's standard frame or frameless

type, but in either case the structural integrity requirements of DoT Safety Regulation 178.340 shall be met. Structural members shall support the running gear, upper fifth wheel plate and landing gear.

* 3.6.1.1 Frame. Semitrailer frame members shall be adequately braced with a sufficient number of crossmembers to insure stability. When the vehicle is loaded with specified payload (see 3.2.2), the maximum fiber stress in any frame member shall be not greater than 33 percent

of the yield strength of the materials used. Under all conditions of operation, the frame members shall maintain chassis alinement without applying stress to the bulkheads, the cabinet or the