TM 5-3895-385-23-1
0003
TECHNICAL PRINCIPLES OF OPERATION
Screed
Figure 1. BMPM Screed -- Left Side (Extended).
The BMPM contains an electrically-heated floating screed (Figure 1, Item 1) that is a self-contained, attachable
unit incorporating hydraulics for raising and lowering the unit and an electric heating system powered by an on-
board generator.
The screed has two 45-inch (in) (1.14-m) hydraulically-operated screed extensions, which, when deployed, allow
paving a strip of paving material up to 15.5 ft (4.7 m) in width and up to 8 in (203-millimeters (mm)) in depth. It is
equipped with a variable crown system that can create crowns and valleys on the paving material being
distributed.
Four hydraulic-mechanical activated vibrators operate at 500 3,500 Vibrations Per Minute (VPM) each and can
compact paving material to an 8-in (0.2-m) depth. Normal compaction density yields 88 90% as measured
directly behind the screed. The vibrator motors are located on each side of the main screed unit. The screed can
be raised, lowered, and locked in the raised position for travel and is delivered with an anti-skid operator platform
containing ergonomically-designed and -located controls for paving thickness, crowning, slope, and grade.