Universal Air Tools UT8026 - Manual (Page 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 (21) 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 3/8" 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 springback.
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.
Dismantling and Assembly Instructions
Disconnect from air supply
Grip housing (1) in a vice then loosen 4 cap screws (5) and take off
hammer case (46)
and reverse bushing (25). Pull out the complete air motor and
dismantle by removing the retaining ring (28). Tap off the front end
plate (34) and pull out the rotor (32) then remove the 6 rotor blades
(33). Take out the hammer cage (38) from the hammer case (46)
and remove the gasket (37). Pull out 2 hammer pins (40) then slide
out the anvil (41) it is now possible to remove the 2 hammer dogs
(39) from the hammer cage (38)
To remove the trigger assembly first knock out the spring pin (2) from
the housing (1) then you can pull out the trigger (19) and o-ring (18).
Removing the throttle assembly, first unscrew the inlet bushing (17)
and remove o-ring (18) them take out throttle spring (11) throttle
valve (10) and finally the valve seat (9).
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 (39) and anvil (41) particular around the square drive. Check
carefully cage (38) Make sure that the faces of the end plate (34)
abut cylinder (30) 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 Take out screw (48) and pour
lubrication oil about 15cc into the hammer case (46) then replace
screw (48). Connect tool to suitable air supply and run the tool slowly
for 5 seconds to allow the oil to circulate.
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 in hose
adaptor (17) 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
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.