Hymair AT-231 User manual
Copyright to be reserved by Hymair Revision: 01 (2004)
INSTRUCTION MANUAL
Thanks for your purchasing our air tools
and please read this Instruction Manual carefully
and thoroughly before operating the tool to do your best jobs.
1/2 H. D. Air Impact Wrench (Model AT-231)
A. Features & Functions
* Durable twinhammer impact mechanism.Pressure-feed lubrication.
* Adjustablepower regulator.Variable speed.
* Sheer power and performance features to tackle tough jobs with ease and proven
durability.
B. Operating Instructions
1. Operation
The tool featuresan air regulator(at the topback of thetool) allowing youto vary the
amount of torqueexerted on thenut or boltyou are workingon. Setting 0 is the
lowest setting andSetting 5 is the highestsetting and providesthe biggest torque
and speed.
2. Loosening
- Step 1:Attach the correctsize socket tothe anvil.
- Step 2: Setthe compressor’s pressure regulator to 90PSI. Do not set the
compressor’s outlet regulator above 90PSI.
- Step 3: Connectthe tool tothe air compressor’s hose. If leakage is detected,
disconnect the airhose and fixit correct beforeuse.
- Step 4: Placethe socket overthe nut toloosen.
- Step 5: Gripthe tool firmly. Press theREVERSE Valve forward atthe top backof
the tool. Pressthe trigger tostart the tool.
(Caution: Make sure the nut orbolt can withstandthe impact wrench’s working torque.)
* Note:
- If the toolcannot loosen thenut, DO NOTraise the outletpressure of theair
compressor.
- If the tool’s air regulatoris set ina low setting,you may raisethe setting andtry
again. If thetool’s airregulator is alreadyset on 5 setting, do notcontinue
attempts to loosenthe nut withthe tool. Useother appropriate toolsand methods
Toloosen the nut.
- When the nutis removed, stopthe tool byreleasing the triggerand remove the
tool from thenut. Remove thenut from thesocket if needed.
3. Tightening
(The working torque of the impact wrench is 585 feet/lbs. Make sure that the nut or
bolt you areusing the toolto tighten canwithstand the ratedtorque.)
- Step 1:Tighten thenut as faras you canby hand.
- Step 2:Place the socketon the nut.Press the REVERSEValve backward at the top
back of thetool. Press thetrigger to startthe tool.
* Note:
- If the tool stalls while tightening, DO NOT raise the outlet pressure of the air
compressor above 90PSI.
- If the tool’s air regulator is seton a low setting, it may be raised andtry again. Ifthe
nut will not tighten at the maximum setting, do not continue attempts to tighten the
nut. Use otherappropriate tools andmethods to tightenthe nut.
- When the nut has been tightened, removethe tool andsocket. Do notover-tighten.
- If available, check the recommended torque specifications for the nut. You should
use a torquewrench to torquethe nut afterusing the impactwrench.
C. Air Supply (please refer to the diagram below)
1. Make sure that the air compressor being used for the air tool operation supplies the
correct output (CFM).
2. Turnthe throttle inthe off position when connectingthe tool tothe air supply.
3. Use normal90psi (or ranging from 6.0 to 8.0kg.) air pressure while running the tool.
High pressure and unclean air will shorten the tool’s life due to faster wear and also
may create ahazardous situation.
4. Drain the air tank daily. Water in the air line may enter the tool and damage the tool
mechanism at theoperation.
5. Clean the air inlet filter cartridge weekly. The recommended hook-up procedure can
be viewed inthe diagram below.
6. Line pressure should be increased accordingly to make up for extra long air hoses
(usually over 8 meters). The minimum hose diameter should be 1/4 I.D. and the
fittings should have the same inside dimensions. But usually a 3/8 I.D. air hose is
recommended for airsupply to getthe best functionof air tooloperation.
7. Use properhoses and fittings. We do not suggest connecting quick changecouplings
directly to the tool since they may cause failure due to vibration. Instead, add a
leader hose andconnect coupling betweenair supply andhose whip.
8. Keep hoses away from the heat, oil and sharp edges. Check hoses for wear before
individual use. Makecertain that allconnections are insecurity.
D. Safety Instructions
1. Approved eye protector must be worn at all times. Be sure to use a dust mask since
the tool operation may creates dust which is harmful to health. If necessary, ear
protector and glovesshould be used.
2. Always keep good balance of body and footing. Secure work with clamps or vice so
both hands canbe free tooperate the tool.
3. Be sure all clothing is tight to prevent entanglement with running tools. Remove
your jewelry andwatch for safetypurpose.
4. Be sure that working area is clear of foreign objects and that no people are within
immediate access of tool operation scope. The working place shall be well
ventilated.
5. Disconnect theair hose beforechanging or adjustingany inserted tools/accessories.
6. Be surethe tool isin off position before connectingit to theair hose.
7. Disconnect the tool when it is not in use. Release the on-off device in case of energy
supply failure.
8. Never carrytool by hose.
E. Maintenance And Lubrication
1. If you are not using an air line oiler, lubricate the air motor by using an oil pot or an
oil injector through the air inlet and then run the tool. Several drops of SAE #10
lubricant or sewing machine lubricant is acceptable for this purpose. Do not use
detergent oil.
2. Before connecting the hose for operation, apply 4 or 5 drops of #10 spindle oil at the
air inlet and trigger mechanism and work the trigger mechanism a few times to
lubricate. Avoid the misuse of thicker oil which may lead to the reduced
performance or malfunction.
3. Oiling isnecessary within 1or 2 hoursof continuous operation.
4. Afteroperation, take off the airhose and pour 4 or 5 drops of #60 spindle oil into the
air inlet, then connect the hose again to run the tool for a few seconds, which can
prolong the toollife.
5. Clean airinlet filter cartridgeon the airline weekly.
F. Warnings
1. Never usethe tool inpotentially explosive atmospheres.
2. Keep your body in well balanced position and always wear gloves to reduce the risk
of crushing causedby torque betweena reaction barand work-piece.
3. Unexpected tool movement due to reaction forces or breakage of inserted tool or
reaction bar maycause injuries.
4. Prevent long hair or loose clothing from drawing in while operating the tool. You
may get the risk of being injured if the handkerchief, necktie etc. are not kept away
from the runningtool.
5. The noise emission (sound pressure level) at the workplace may exceed the normal
standard ---usually 85dB(A).In this case,a quality earprotector should be used.
6. Unexpected directionof inserted toolmovement could casea hazardous situation.
7. Slip / Trip / Fall is a major cause of serious injury or even death. Be aware of excess
hose left on your walking way or on the working surface and be aware of the
whipping air hosetoo.
8. Excessive high air pressure and too much free rotation may speed up the wear of the
tool and maycause dangerous situation.
9. Continuous operation and bad working condition will injure hands. Once hand
numbs or aches , operator shall stop the tool for a while for relaxing and re-start the
work after recovery. Operator shall immediately see a doctor if such a serious
symptom occurs.
10. Never change the inner construction and design, which may cause a danger in
operation.
G. General Trouble Shooting
* Troubles:
- Tool does not run at a normal speed or at a variable speed
- The motor blocks
- Automotive start whenconnected to compressedair
- Torque reduces
- Abnormal vibrating -Easy hot rising atthe housing
* Causes:
- Air supply isnot enough (airpressure not ina required standard)
- Speed controller/switch breaksdown
- Rotor blades breakor wear out
- Dust gets intothe motor
- Throttle lever orstarting trigger malfunctions
- Air leakage atthe inlet orsomewhere else
- Bearing(s) damages
- Correspondent O-ring(s) wearsout or outof position
- Lack of lubricating
* TroublesShooting:
- Check the airhose to seewhether it isblocked or twistedfor less airsupply.
- Check the aircompressor to gainthe correct airpressure required.
- Replace rotor blades
- Disassemble the tooland clean theinner structure underproper instructions
- Check and fixthe throttle leveror starting triggerfor accurate operation
- Check the airleakage and fixit under properinstruction
- Replace new bearing(s)
- Replace the damagedO-ring(s) or putit back incorrect position
- Oil / Lubricatethe tool consistentlyuntil it gainsthe right speedand torque
* Note: For any other special troubles which cannot be settled down by the operator,
please contact theselling agent fromwhom you purchasethe tool.
H. Storage
Avoid to store the tool in a location subject to high humidity, which mayresult in rusty
mechanism inside thetool. Before storing,oil the toolat the airinlet with proper
Spindle oil andrun it fora few seconds.
I. Disposal
When the tool is seriously damaged or out of life, leave it in a resource recycling can.
Never drop itinto fire.
J. Ordering Spare Parts
1. Contact the sale agent from whom you purchase the tool for spare parts ordering for
any necessary replacementfor continuous useof tool andextending the toollife.
2. In ordering spare parts and components, give each spare part number and order
quantity.
Thank you.
01
02
03
04
05
05
06
07
08
09
10
11
11A
12
13
14
15
16
17
18
22
23
24
25
26
27
29
30
31
32
33
34
35
35
36
37
38
39
38A
40
41
43
44
45
SPARE PARTS LIST
TECHNICAL DATA:
* Square Drive: 1/2” Capacity Bolt Size: 5/8” (16mm) Free Speed: 7,000 rpm
* Max. Toruqe: 585 ft-lb (745 N-M) * Air Inlet: 1/4” BSP or NPT * Air Hose(ID): 3/8”
3
* Avg.Air Consumption: 8 CFM(0.23m /min)
Part No.
Description
Qty.
Part No.
Description
Qty.
01
02
03
04
05
06
07
08
09
10
11
11A
12
13
14
15
16
17
18
22
23
24
Motor Housing
Warning Label
Grease Fitting
Reverse Valve Bushing
Reverse Valve Bushing Seal
Throttle Valve Assembly
Throttle Valve Face
Throttle Valve Spring
Throttle Valve Stem
Air Strainer Assembly
Trigger
Plug
Trigger Pin
Reverse Valve
Reverse Valve Detent Ball
Reverse Valve Detent Spring
Reverse Valve Knob
Reverse Valve Knob Screw
Nameplate
Rotor
Rear Rotor Bearing
Front Rotor Bearing
Rear Rotor Bearing Retainer
Cylinder
Cylinder Dowel
Vane Packet
Front End Plate
Rear End Plate
End Plate Gasket
Motor Clamp Washer
Hammer Frame Assembly
Hammer Pin
Hammer Frame Rear Washer
Hammer
Hammer Case
Hammer Case Pilot
Hammer Case Gasket
Hammer Case Bushing
Hammer Case Cap Screw
Standard Anvil
Extended Anvil
Sccket Retainer
Retainer O-Ring
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
6
1
1
1
2
1
2
1
2
1
1
1
1
3
1
1
1
1
25
26
27
29
30
31
32
33
34
35
36
37
38
38A
39
40
41
43A
43B
44
45
1/2 H.D. Air Impact Wrench (Model:AT-231)
