Enerpac SCJ-Series - Manual (Page 3)

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pressure is achieved, the valve on the pump is switched to the
retract position. The valve maintains pressure on the strand.
Engaging the pump causes the wedge setter to push forward and
seat the wedges; when a preset pressure is achieved, the jack will
then begin its return stroke.
Capacities
20 ton jacks -- stress strand up to .5" in diameter. For use with
smaller strand, jack grippers of different sizes are available.
30 ton jacks -- stress strand up to .6" in diameter. For use with
smaller strand, jack grippers of different sizes are available.
4.2 DA Series
The DA series of jacks are manufactured from a single piece of
hardened steel. The durable, lightweight, and compact design
make the DA jacks the tool of choice for elevated construction
projects.
Double-Acting System
5DA1 / 5DA1AL - 20 ton, double-acting jack with power-seating
wedge seater, 0.5" strand
6DA1 - 30 ton, double-acting jack with power-seating wedge seater,
0.6" strand
The DA series jacks are double-acting, meaning that the jacks
extend and retract using hydraulic power. Both jacks use power
wedge seaters to seat the wedges into the anchor. After the
desired stressing pressure is achieved, the valve on the pump is
switched to the retract position. The valve then maintains pressure
on the strand. Engaging the pump causes the wedge seater to
push forward and seat the wedges; when a preset pressure is
achieved, the jack will then begin its return stroke.
Capacities
5DA1 / 5DA1AL, 20 ton jack -- stresses strand up to .5" in
diameter. For use with smaller strand, jack grippers of different
sizes are available.
6DA1, 30 ton jack -- stresses strand up to .6" in diameter. For use
with smaller strand, jack grippers of different sizes are available.
5.0 OPERATION
1. Improper care and use of stressing equipment may result in
property damage, and/or personal injury.
Only trained, qualified personnel should be allowed in the
immediate vicinity of equipment during use.
Personnel doing the stressing and inspectors should remain
clear of the strand being stressed at all times. Never permit
anyone to stand in the immediate vicinity of the jack and the
pump while stressing.
2. Open the jack gripper by pulling back on the gripper handle or
cable.
3. Position the jack on the strand to be stressed and push
forward until the jack nose bears on the anchor. Never attempt
to adjust the position of the jack, either by striking or pushing
after any load has been applied. Remove the jack and
reposition if necessary.
4. Push the jack grippers forward to engage the strand making
sure that:
a. Jack grippers are parallel to avoid damage to themselves or
the strand.
b. Strand is in proper position within jack grippers.
5. Place the pump 4-way valve in stressing position.
6. Operate the pump by use of the pendant switch. (Use of the
pendant switch allows the operator to stand to the side of the
pump, out of harm's way, should the tendon or jack grippers
fail.)
7. On pumps equipped with a sequence valve or automatic
seating valve:
a. Start pump motor and run until proper pressure is indicated
on pressure gauge.
b. Switch 4way valve to retract position.
c. Pressure will remain on the pressure side of the jack, but
gauge pressure will drop to zero and start to rebuild
pressure.
d. When preset pressure is achieved (depending on the
equipment used), the seating plunger will be fully
pressurized, a popping noise will be heard, and the jack will
start to retract.
e. When the jack is fully retracted, stop the pump and switch
the 4-way valve to stressing position. The seating plunger
should fully retract. It is important to stop the pump and
switch the valve quickly to avoid excessive pressure build-
up in the jack after it has completely returned. This
excessive pressure build-up can cause premature failure
of the jack seals, hoses and fittings.
f. Slide the jack forward to release the jack grippers and
remove the jack from the strand.
Note: For jacks without power seating wedge seaters, after proper
gauge pressure is achieved, by switching the valve to the retract
position, the jack will begin to retract.
5DA1 / 5DA1AL / 6DA1
ZU4 electric pump with
VM43LPS post-tensioning valve
Pressure hose connects to "A"
port on control valve.
Retract hose connects to "B"
port on control valve
Pressure seat hose
connects to "GB" port
on control valve