ARMY TM 5-5420-212-10-1
MARINE CORPS TM 08676A-10/1-1
b.
Jack Operation
Before a load is applied to a jack, check that the jack head is inserted fully into the jack hood and when using with
a building frame check that jack base is pushed firmly into jack seating.
To raise the jack
(1)
Use jack handle to ensure that release valve is fully closed. DO NOT OVERTIGHTEN.
(2)
Insert jack handle into most convenient hole in quadrant and operate. When the jack is at maximum lift
a safety mechanism comes into operation and prevents further movement of the ram. As a check, the
jack handle is equal in length to a fully extended jack.
To lower the jack
(1)
Unscrew the release valve with the jack handle not more than one and a half turns. The amount of
opening governs the speed of the ram. Only open the valve very slightly if the jack is to be lowered
slowly.
To transport the jack
(2)
When 15T jack is carried in equipment basket the filler cap must be uppermost. When a 20T jack is
carried in equipment basket the air vent on the side of the jack must be kept uppermost.
(3)
Jack must be lifted by the body handle and NOT by the swivel head.
c.
Jack Post and Jack - Single Story
A launching nose pin is used to connect the jack post to the outer brackets on the bankseat beam. The nose pin
is secured by a retainer clip. On single story bridges the wedge is used to pack out the jack post and the hook is NOT
engaged on the bankseat beam ledge. The jack is placed on timber packing (3 in x 8 in x 36 in) parallel to the bankseat
beam, or, if conditions are bad, a single story baseplate with a jack support. Positioning the wedge between the jack post
and the bankseat beam rail ensures that the bridge will clear the jack and baseplate when it is lowered to the ground.
If the jack post is to be fitted before launch or de launch, it will be necessary to secure the jack post by raising the
wedge and hooking the jack post to the bankseat beam rail. Then, when the jack post is to be used for jacking the wedge
must be repositioned to the down position as shown.
WARNING
When fitting or carrying the jack post, hold the jack hood to prevent it from falling.
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