Universal Air Tools UT5315 - Manual (Page 2)

Safety Rules When Using an Impact
Wrench
1) Read all the instructions before using this tool. All operators
must be fully trained in its use and aware of these safety rules.
All service and repair must be carried out by trained personnel.
2) The socket used must be of the correct drive size and the
"impact" type. Never use sockets other than impact type.
3) Do not use sockets with excessive wear to the input and
output drives. Check that the square on any other type of drive
or the impact wrench is not cracked or excessively worn before
fitting or changing socket, extension, etc. Make sure that the
socket is firmly fixed to the tool.
4) Always ensure that a stable position or footing is adopted
before using the tool.
Dismantling & Assembly Instructions
Disconnect from air supply.
Remove red boot (56) remove clamp screw (13) and drain the
oil in the front end into a suitable container. Grip motor housing
(1) in a vice and tap out spring pin (28). Pull out air regulator
(26) with o-ring (27). Take out screw (9) and remove deflector
(8). Unscrew retainer plug (31) take out stop pin (29) and
spring (30) and it will be possible to push out the reverse valve
(25) from the motor housing (1). Unscrew 4 off screws (4) with
washers (5) and tap the square drive end of the anvil shank
(51) and this will drive the motor and hammer assemblies out
of the rear end of the motor housing (1). Pull off the hammer
mechanism from the motor assembly. The hammer
mechanism maybe pulled apart separating the anvil shank (51)
spring (50) drive cam (48) 2 off anvil hammer bars (49) steel
ball (47) drive cam base (46) hammer cage (45) and anvil
washer (52). Note the notch in the spline of the anvil shank
(51) and the wide splined tooth drive cam (48) for correct
reassembly. Anvil collar (54) and o-ring (53) maybe prised off
the anvil shank (51) oil seal (7) maybe prised and the anvil
bushing (6) pressed out of the motor housing (1). Unscrew 3
off rotor screws (43) and washers (44) and take off end cap (2)
and gasket (3). It is then possible to pull the motor assembly
apart but first note the orientation of the cylinder (37) to the
front and rear end plates before pulling off the front and rear
plate assemblies from the rotor (38). Remove 6 off rotor blades
(39) from rotor (38). With a suitable punch tap out bearings
(32) and (41) remove oil seals (33) from rear plate (40) and
front plate (34). Prise out o-ring (35) from the grove in front
plate (34).
Reassembly
Clean all component parts and examine for wear and cracks
etc. before reassembling Look in particular to wear and cuts on
o-rings and oil seals, wear on rotor blades and wear and
cracks on hammer bars (49) and anvil (51) particular around
the square drive. Check carefully cage (45). Make sure that the
faces of the end plates (40) and (34) about cylinder (37) are flat
and free from burrs and surface marking. If necessary lap faces
on a flat, very fine grade of abrasive paper. Lightly coat all parts
with suitable pneumatic tool lubricating oil and reassemble in
the reverse order (See note below).
Note in particular
a) that the hammer bars (49) -2 off are located in the two
identical shaped grooves in the hammer cage (45).
b) that the cut away portion of the front flange of the cylinder
(37) abuts the two notches in the face of the front plate
(34).
On completing assembly ensure that all parts are locked tight
and the anvil rotates and the trigger, reverse valve and air
regulator mechanisms operate freely. Remove oil plug (13) and
pour in one ounce (28cc) of standard SAE20 grade oil. Do not
over fill as this will result in a reduction of power in the tool
performance. Pour approx 5ml of a good quality pneumatic
lubricating oil (preferably one containing a rust inhibitor) into the
air intake with the trigger depressed. Connect tool to a suitable
air supply and reset for operation required. Refer to section on
operation instructions.
into the intake bushing (21) a teaspoonful (5ml) of a suitable
pneumatic motor lubricating oil preferably incorporating a rust
inhibitor. Reconnect tool to air supply and run tool slowly for a
few seconds to allow air to circulate the oil. If tool is used
frequently lubricate on daily basis and if tool starts to slow or
lose power. When lubricating, also ensure that screen (1) is
clean.
It is recommended that the air pressure at the tool whilst the
tool is running is 90 p.s.i./6.3 bar. The tool can run at lower and
higher pressures with the maximum permitted working air
pressure of 100 p.s.i./7.0 bar. For a lower air pressure the tool
will give a lower output for a given setting of the air regulator set
for 90 psi operation and an increased output for higher
pressures. Hence it is possible that changes in supply pressure
can give situations where the fastener is under or over
tightened. For changes in pressure, the regulator position and
application should be reassessed.
It is recommended that joint tightness of the threaded fastener
assembly be checked with suitable measuring equipment.
Page No 2
Operating
The output of the impact wrench in prime working condition is
governed by mainly three factors
a) the input air pressure
b) the time the impact wrench is operated on the joint. Normal
time for joints of average tension requirement 3 to 5 seconds
c) the setting of the air regulator for a given joint at a given
pressure operated for a given time.
The air regulator item (26) can be used to regulate the output of
the impact wrench if no other control means is available. It is
strongly recommended that an external pressure regulator
ideally as part of a filter/regulator/lubricator (FRL) is used to
control air inlet pressure so that the pressure can be set to help
control the tension required to be applied to the threaded
fastener joint.
There is no consistent reliable torque adjustment on an impact
wrench of this type. However, the air regulator can be used to
adjust torque to the approximate tightness of a known threaded
joint. To set the tool to the desired torque, select a nut or screw
of known tightness of the same size, thread pitch and thread
condition as those on the job. Turn air regulator to low position,
apply wrench to nut and gradually increase power (turn regulator
to admit more air) until nut moves slightly in the direction it was
originally set. The tool is now set to duplicate that tightness,
note regulator setting for future use. When tightening nuts not
requiring critical torque values, run nut up flush and then tighten
an additional one-quarter to one-half turn (slight additional
turning is necessary if gaskets are being clamped). For additional
power needed on disassembly work, turn regulator to its fully
open position. This impact wrench is rated a 3/4" bolt size.
Rating must be down graded for spring U bolts, tie bolts, long
cap screws, double depth nuts, badly rusted conditions and
spring fasteners as they absorb much of the impact power.
When possible, clamp or wedge the bolt to prevent spring back.
Soak rusted nuts in penetrating oil and break rust seal before
removing with impact wrench. If nut does not start to move in
three to five seconds use a larger size impact wrench. Do not
use impact wrench beyond rated capacity as this will drastically
reduce tool life.
NOTE: Actual torque on a fastener is directly related to joint
hardness, tool speed, condition of socket and the time the tool
is allowed to impact.
Use the simplest possible tool-to-socket hook up. Every
connection absorbs energy and reduces power.