Universal Air Tools UT8327 - 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.
5) Ensure that the tool has been correctly set up on a test joint. Incorrect
set up could cause joint breakage with sudden and unexpected
movement of the tool.
6) Use only correct spare parts for repair.
7) Always ensure that the reverse valve is in the correct position before
operating the tool. Do not run the tool unless the socket is first located
on the joint.
8) Check hose and fittings regularly for wear. Use quick connect
couplings only as recommended. See "Putting into Service". Do not
carry the tool by the hose and ensure that the hand is away from the
on/off valve when carrying.
9) Do not attempt to hold or guide the socket by hand when the tool is
running.
10) Do not exceed maximum recommended air pressure.
11) Use safety equipment as recommended.
12) The tool is not electrically insulated. Do not use where there is a
possibility of coming into contact with live electricity.
13) Preferably shut off the air supply before changing sockets or at least
ensure that the hands are well clear of the operating trigger.
14) Take care against entanglement of moving parts of the tool with
clothing, ties, hair, cleaning rags, etc.
15) When loosening fasteners first ensure that there is sufficient
clearance behind the tool to avoid hand entrapment. The tool will move
away from the threaded joint as the nut/bolt etc. is loosened and rides
up the thread moving the tool with it.
16) Only use extensions, adaptors and universal joints suitable for use
with impact wrenches.
17) If the tool appears to malfunction remove from use immediately
and arrange for service and repair.
Dismantling and Assembly Instructions
Disconnect from air supply.
Grip housing (10) in a vice then loosen 4 screws (30) and take off
hammer case (2) and rear cover (29). Pull out the complete air motor
and dismantle. Tap off the front end plate (17) and pull out the rotor (18)
then remove the 6 rotor blades (38). Take out the hammer cage (8)
from the hammer case (2) and remove the gasket (9) pull out 2
hammer pins (7) then slide out the anvil (6) it is now possible to remove
the 2 hammer dogs (11) from the hammer cage (8).
Removing the throttle assembly, first unscrew the inlet bushing (37) and
pull off the O-ring (36) and washer (35) and flick out the exhaust
deflector (34) them take out throttle spring (33) throttle valve (32)
muffler (39) and finally the retainer (31).
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 dogs (11)
and anvil (6) particular around the square drive. Check carefully cage (8)
Make sure that the faces of the end plate (17) abut cylinder (20) 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.
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.
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 reverse switch (23) 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 1 1/8" 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.