3.12 Vibrating screen l The vibrating screen shall be 4 feet wide
by 10 feet long, with three decks. Screen cloth installed on the top
deck shall have a l-inch-square-opening; the second deck a l/2-inch-
square-opening; and the bottom deck a l/b-inch-square-opening. The
vibrating screen shall consist of a live frame with screen cloths, a
vibrating mechanism, suitable vibration isolators, and drive, and may
include a stationary frame. Chutes and hoppers for feed and discharge
shall be provided.
3.12.l Stationary frame. When provided, the stationary frame shall
be structural steel or castings.
3.12.2 Live frame. The live frame of the screen assembly shall be
steel plates an structural steel members with crossmembers to hold the
5-foot screen cloths. The frame shall prevent movement of the screen
cloth during full-load operation. The crossmembers shall create a
and the crossmembers. Screen cloths shall be changeable by using
common tools. The frame shall be balanced to provide an even flow of
material across the full width of the cloth.
3.12.3 Screen cloth. Screen cloth shall be furnished in 5-foot by
4-foot sections and shall conform to MS39127. Two 5-foot sections of
each size listed in table I shall be furnished in addition to those
specified in 3.12.
126.96.36.199 Wire. All screen cloth shall be made of crimping-grade,
oil-tempered, standard-heavy wire conforming to National Sand and
Gravel Association Circular No. 80, table 3, grade B, carbon range
0.55 to 0.70, drawn and hardened. Wire size shall be as shown in
Table I. Wire sizes