3.4.2 Steel Pipe.
(See 3.4.3 Of MIL-P-19380J.)
3.4.3 Stainless steel. Stainless steel, shown in CEL Drawing 77-26-8F,
shall be in accordance with ASTM A167, type 304.
3.5 Construction. (See 3.5 of MIL-P-19380J.) pontoon units shall be
fabricated as specified herein and as shown on the applicable drawings listed
in Table I. Pontoon units shall consist of welded structural frames covered
on all sides with steel plate to form an airtight unit and shall include only
such components or parts thereof as are welded permanently to the pontoons.
Threaded parts shall conform to FED-STD-H28. American National Taper Pipe
Thread form shall be used for flanges and plugs. Flanges shall be standard
cast, forged steel, or malleable iron, boiler type, of the sizes shown on the
applicable drawings. Drainage plugs shall be of cast iron and shall be
installed using an antisieze tape conforming to MIL-T-27730 on threads. Holes
for A6B bolts shall be maintained at 1-5/8 inch diameter during assembly and
welding of corner components. Unless otherwise specified (see 6.2), the hatch
cover assembly, Mark H6, shall be furnished loose for field installation.
Welding shall be in accordance with the AWS Structural Welding Code using AWS
recommendations pertaining to electrodes for materials, types of welds, and
welding processes utilized. When specified (see 6.2), knocked-down pontoons
shall be furnished. When knocked-down pontoons are specified, all material
shall be cut, bent, and drilled or punched as specified herein and on the
applicable drawings; boiler flanges and the manhole ring shall be welded in
place. The manhole cover shall be tack welded in the manhole opening. The
nut receptacle shall be cut, formed, and welded into a subassembly prior to
shipment. All pieces shall be shipped ready for assembly after delivery.
Construction of pontoons shall be such that welding operations shall be
performed in a flat, horizontal position, wherever possible. Where welding is
performed in an alternate position, the welder must be qualified In the
Pontoons, Steel sectional, P-series.