ARMY TM 5-5420-212-10-1
MARINE CORPS TM 08676A-10/1-1
(2)
Command: Locks out.
CAUTION
Personnel are advised to use extreme caution during locking and unlocking of rollers. Once the
rollers are locked or unlocked, move hands and arms from between the bridge and adjustable
supports. Do not put hands or arms into that area more than necessary. Failure to stay alert while
operating locks can result in injury.
(3)
Action: Personnel. Personnel on CRB roller locks will use the 19 mm ratchet wrench to operate both
rollers on each rocking roller to the full up position. When both rollers are up, both of the moveable
bearing pads on each rocking roller will be pulled to the full out position, CRB personnel will report to the
NCOIC that the CRB is ’unlocked’ once report is received, NCOIC, roller lock (FRB/RRB) personnel, and
vehicle driver will follow steps a. (1) through (8) to unlock rollers and boom bridge to desired panel point.
(4)
Command: Locks in.
(5)
Action: NCOIC, roller lock (FRB/RRB) personnel, and vehicle operator will follow step a. (10) to lock
rollers.
(6)
Action: Personnel. After the FRB/RRB are locked, the personnel on the CRB rollers will push both
moveable bearing pads to the full in position. When both moveable bearing pads are in, the 19 mm
ratchet wrench will be used to operate both rollers on each rocking roller to the full down position, CRB
personnel will report to the NCOIC that the CRB is ’locked’.
(7)
NCOIC. NCOIC will direct crews back to other duties.
4-20.
JACKING
After launching, it is necessary to lower the bridge down from the roller beam. Before disassembly, the bridge has
to be raised onto the roller beams. This is achieved by jacking, using a crane (para. 4-22) or davits (para. 4-21).
a.
General Principles
Jacking down both ends of bridge together to save time is NOT allowed. The sequence to be followed is
ALWAYS:
(1)
Lower far end of bridge using jack in the landing roller pedestal (single story over 8 bays and all double
story) or jack, jack post and packing (single story up to 8 bays).
(2)
Transfer weight of bridge from roller beam to two jacks on home bankseat beam.
(3)
Jack onto packing when second or third stage jacking is necessary.
These general principles apply in the reverse when jacking up during disassembly.
WARNING
Never jack at one end of a bridge unless the other end Is fixed on locked rollers, on the ground, or
secured to vehicle when on the capsill or forward roller beams.
Always ensure that head of jack Is Inserted correctly In jack hood and does not rest on edge or
rim.
Never use Inner central bracket on bankseat beam for jacking up or down. Outer central bracket
can only be used on single story bridges up to 5 bays.
4-71
