Miller Electric DB1812R User manual

Visit our website at
www.MillerWelds.com
Processes
Description
TIG Torch
OM-1603 199 528C
1/2005
TIG (GTAW) Welding
DB1812R And DB1825R
Diamondback Series
GTAW Torches
ESPAÑOL FRANÇAIS ENGLISH

TABLE OF CONTENTS
SECTION 1 −SAFETY PRECAUTIONS FOR GTAW TORCHES − READ BEFORE USING 1. . . . . . . . . . . . . .
1-1. Symbol Usage 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-2. GTAW Torch Hazards 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
EMF INFORMATION 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 2 − SPECIFICATIONS 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-1. Specifications 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-2. Duty Cycle 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 3 − INSTALLATION 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-1. Required Torch Parts And Torch Assembly 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-2. International Style Connector Assembly 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-3. Connecting Torch 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 4 − MAINTENANCE & TROUBLESHOOTING 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-1. Routine Maintenance 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-2. Troubleshooting 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 5 − SELECTING AND PREPARING TUNGSTEN ELECTRODE FOR DC OR AC WELDING 9. . . .
5-1. Selecting Tungsten Electrode (Wear Clean gloves To Prevent Contamination Of Tungsten) 9. . . . . . . .
5-2. Preparing Tungsten Electrode For Welding 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 6 − GUIDELINES FOR TIG WELDING (GTAW) 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-1. Positioning The Torch 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-2. Torch Movement During Welding 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-3. Positioning Torch Tungsten For Various Weld Joints 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 7 − PARTS LIST 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
WARRANTY

ENGLISH
OM-1603 Page 1
SECTION 1 −SAFETY PRECAUTIONS FOR GTAW
TORCHES − READ BEFORE USING
SR6_1/00
1-1. Symbol Usage
Means Warning! Watch Out! There are possible hazards with this
procedure!The possible hazards are shown in the adjoining symbols.
This group of symbols means Warning! Watch Out! Possible ELECTRIC SHOCK and HOT PARTS hazards.
Consult symbols and related instructions below for necessary actions to avoid the hazards.
Marks a special safety message.
Means NOTE; not safety related.
1-2. GTAW Torch Hazards
PROTECT YOURSELF AND OTHERS FROM POSSIBLE SERIOUS INJURY OR DEATH. KEEP CHILDREN
AWAY. PACEMAKER WEARERS KEEP AWAY UNTIL CONSULTING YOUR DOCTOR.
In welding, as in most jobs, exposure to certain hazards occurs. Welding is safe when precautions are taken. The
safety information given below is only a summary of the more complete safety information found in the welding
power source Owner’s Manual. Read and follow all safety precautions.
HAVE ALL INSTALLATION, OPERATION, MAINTENANCE, AND REPAIR WORK PERFORMED ONLY BY
QUALIFIED PEOPLE.
GTAW WELDING can be hazardous.
ARC RAYS can burn eyes and skin.
1. Wear welding helmet with correct shade of filter.
2. Wear correct eye and body protection.
3. Cover exposed skin.
ELECTRIC SHOCK can kill.
1. Always wear dry insulating gloves.
2. Insulate yourself from work and ground.
3. Do not touch live electrode or electrical parts.
4. Repair or replace worn, damaged, or cracked
torch or cable insulation.
5. Turn off welding power source before changing
tungstenelectrode or torch parts.
6. Keep all covers and handle securely in place.
WELDING can cause fire or explosion.
1. Do not weld near flammable material.
2. Do not weld on closed containers.
3. Watch for fire; keep extinguisher nearby.
NOISE can damage hearing; SOME
APPLICATIONS, SUCH AS PULSING,
are noisy.
1. Check for noise level limits exceeding those
specifiedby OSHA.
2. Use approved ear plugs or ear muffs if noise level
is high.
3. Warn others nearby about noise hazard.
HOT SURFACES can burn skin.
1. Allow torch to cool before touching.
2. Do not touch hot metal.
3. Protect hot metal from contact by others.
FUMES AND GASES can be hazardous
to your health.
1. Keep your head out of the fumes.
2. Ventilate area, or use breathing device.
3. ReadMaterial Safety Data Sheets (MSDSs) and
manufacturer’s instructions for material used.
BUILD UP OF GAS can injure or
kill
1. Shutoff shielding gas supply when not in
use.
2. Always ventilate confined spaces or use
approvedair-supplied respirator.

OM-1603 Page 2
EMF INFORMATION
ConsiderationsAbout Welding And The Effects Of Low Frequency
Electric And Magnetic Fields
Weldingcurrent, as it flows through welding cables, will cause electro-
magnetic fields. There has been and still is some concern about such
fields.However, after examining more than 500 studies spanning 17
years of research, a special blue ribbon committee of the National
Research Council concluded that: “The body of evidence, in the
committee’s judgment, has not demonstrated that exposure to power-
frequency electric and magnetic fields is a human-health hazard.”
However, studies are still going forth and evidence continues to be
examined.Until the final conclusions of the research are reached, you
may wish to minimize your exposure to electromagnetic fields when
welding or cutting.
To reduce magnetic fields in the workplace, use the following
procedures:
1. Keep cables close together by twisting or taping them.
2. Arrange cables to one side and away from the operator.
3. Do not coil or drape cables around your body.
4. Keep welding power source and cables as far away from oper-
ator as practical.
5. Connect work clamp to workpiece as close to the weld as
possible.
About Pacemakers:
Pacemakerwearers consult your doctor first. If cleared by your doc
-
tor, then following the above procedures is recommended.

ENGLISH
OM-1603 Page 3
SECTION 2 − SPECIFICATIONS
2-1. Specifications
Model
DB1812R DB1825R
Ampere Rating 350 Amps W/Argon Gas @ 100% Duty Cycle DCEN, ACHF
Cooling Method Water
Cooling Requirements 1.1 quart/minute (1.0 liter/minute)
Tungsten Size .020 Thru 5/32 in (0.5 Thru 4.0 mm)
Cable Options 12-1/2 ft (3.8 m) One-Piece High−Flex 25 ft (7.6 m) One-Piece High−Flex
Dimensions Length: 9 in (229 mm); Handle Diameter: 1−1/8 in (29 mm); Weight: 5.8 oz (165 g)
2-2. Duty Cycle
ContinuousWelding sb1.5* 8/93
100% Duty Cycle At 350 Amperes Using Argon Gas
Duty Cycle is percentage of 10
minutes that torch can weld at
ratedload without overheating.
0
10
Minutes
Definition
EXCEEDING RATED AMPERAGE can damage torch and void warranty.
•Do not exceed rated amperage (see Section 2-1)

OM-1603 Page 4
SECTION 3 − INSTALLATION
3-1. Required Torch Parts And Torch Assembly
Ref. 802 676
Assembling Torch Parts
8
7
5
4
3
6
12
13
14
15
10
12
11
1 Cup
2 ColletBody
3 Heat Shield
4 Backcap Insulator
5 Collet
6 O-Ring
7 Backcap
8 Torch Body
9 Handle
10 Power Cable
11 Water Hose
12 Gas Hose
13 Power Cable Adapter
14 International Style Adapter
15 Water Hose For International
Style Adapter
Assembling Torch Body
Keep connections tight. Replace
cup, heat shield, and backcap as
needed.
16 Tungsten Electrode (See Sec-
tion 5)
Installing Tungsten
To adjust tungsten position, loosen
backcap.
9
16
3-2. International Style Connector Assembly
1 Weld Output Cable
2 Insulating Boot
3 Sleeve
Slide insulating boot onto cable;
strip cable and install sleeve.
4 Connector Body
5 Setscrew
Insert cable with sleeve fully into
connector body, tighten setscrew,
and slide insulating boot over con-
nector.
ST-156 496
Tools Needed:
1
2
3
1 in
(26 mm)
3
4
5

ENGLISH
OM-1603 Page 5
3-3. Connecting Torch
A. Connecting Torch When Using A Freestanding Coolant System
Turn Off welding power source and
cooling system power before in-
stallingtorch.
1 Welding Power Source
2 Regulator/Flowmeter
3 Gas Cylinder
4 Gas Hose (Customer Supplied)
Obtaincorrect length with 5/8-18 right-hand
fittings.
5 Torch
6 Power Cable Adapter
7 Coolant Hose (Customer Supplied)
Obtain correct length with 5/8-18 left-hand
fittings.
8 Coolant-Out Of Torch/Power Cable
(Red)
Connect coolant-out of torch/power cable
to power cable adapter, and connect adapt-
er to weld output terminal.
9 Torch Gas Hose
10 Coolant-Into Torch Hose (Blue)
11 Cooling System
12 Work Clamp
Connect work clamp to a clean, paint-free
locationon workpiece, close to weld.
Use wire brush or sandpaper to clean metal
at weld joint area.
802 560
If applicable, install high-frequency unit.
Tools Needed:
5/8, 7/8, 1-1/8 in
5
11
1
7
2
3
4
6
9
10
8
12

OM-1603 Page 6
B. Connecting Torch To A Dynastyt300 DX Or Maxstar300 DX TIGRunnertUnit
803 311
Tools Needed:
5/8, 7/8, 1-1/8 in
2
3
1
10
5
6
8
11
4
79
12
Turn Off welding power source
power before installing torch.
1 Gas Hose With 5/8-18 Right-
Hand Fittings (Customer Sup-
plied)
Connections:
2 Regulator/Flowmeter
3 Gas Cylinder
4 Coolant System
5 Torch
6 Coolant-Into Torch Hose (Blue)
7 Torch Gas Hose
8 Coolant-Out Of Torch/Power
Cable (Red)
9 International Style Adapter
Connect coolant-out of torch/power
cable to power cable adapter, and con-
nect adapter to weld output terminal.
10 Work Clamp
Connectwork clamp to a clean, paint-
free location on workpiece, close to
weld.
Use wire brush or sandpaper to clean
metal at weld joint area.
11 Welding Power Source
12 Foot Control
C. Connecting Torch To A Syncrowave 250 DX Or 350 LX TIGRunnertUnit
803 311
Tools Needed:
5/8, 7/8, 1-1/8 in
Turn Off welding power source
power before installing torch.
1 Gas Hose With 5/8-18 Right-Hand
Fittings (Customer Supplied)
Connections:
2 Regulator/Flowmeter
3 Power Source
4 Gas Cylinder
5 Coolant System
6 Coolant Hose (Supplied With TI-
GRunner)
7 Power Cable Adapter
8 Torch
9 Coolant-Into Torch Hose (Blue)
10 Coolant-Out Of Torch/Power
Cable (Red)
Connecttorch coolant-out of torch/pow-
er cable to power cable adapter, and
connectadapter to weld output terminal.
11 Torch Gas Hose
12 Work Clamp
Connect work clamp to a clean, paint-
free location on workpiece, close to
weld.
Use wire brush or sandpaper to clean
metalat weld joint area.
13 Foot Control
4
3 1 2
5
6
11
8
10
9
12 7
13

ENGLISH
OM-1603 Page 7
SECTION 4 − MAINTENANCE & TROUBLESHOOTING
4-1. Routine Maintenance
Disconnecttorch before maintaining.
40 Hours
Replace
unreadable
labels.
Repair or
replace
cracked
weld cable.
Clean and
tighten weld
terminals.
Replace cracked parts
Torch Body Torch Cable
4-2. Troubleshooting
Before using troubleshooting table, check selection and preparation of tungsten
electrode according to Section 5.
NOTE
Trouble Remedy
Arc will not start. High frequency presen
t
and visible at the torch.
Check cable and work connections. Be sure weld circuit is complete (see Section 3-3).
and visible at the torch.
Check and be sure shielding gas is present.
Lack of high frequency; difficulty in es
-
tablishingarc.
Select proper size and type tungsten. Properly prepare tungsten according to Section 5.
tablishingarc.
Check cables and torch for cracks or bad connections. Be sure that torch cables are not close to any
grounded metal. Repair or replace necessary parts.
Check torch consumables. Be sure collet and collet body are correctly installed and tightened (see Sec-
tion 3-1).
Check welding power source High Frequency control, and if necessary, check and adjust spark gaps.
Torch gas valve not working properly (if
applicable). Have Factory Authorized Service Station/Service Distributor check valve.
No shielding gas flow from torch. Be sure valves on gas supply are open.
Check cable for kinks or blockage.
Check and tighten all gas supply fittings.
Check cables and torch for cracked insulation or bad connections. Repair or replace (see Section 4-1).
Tungstenelectrode oxidizing and not re
-
mainingbright after conclusion of weld.
Shield weld zone from drafts.
mainingbright after conclusion of weld.
Increase postflow time.
Increase gas flow rate. Check manufacture’s recommendations.
Check and tighten all gas fittings.
Check gas valve and flow meter/regulator.
Select proper size and type tungsten. Properly prepare tungsten (see Section 5).
Excessive tungsten electrode con
-
sumption.
Select proper size and type tungsten. Properly prepare tungsten according to Section 5.
sumption.
Check polarity setting on welding power source (see welding power source Owner’s manual).
Check for proper gas flow rate. Check manufacture’s recommendations.
If torch is water cooled, check torch and cables for water leaks. Repair or replace if necessary (see Sec-
tion 4-1).

OM-1603 Page 8
Trouble Remedy
Wandering arc Shield weld zone from drafts.
Reduce gas flow rate.
Select proper size and type tungsten. Properly prepare tungsten according to Section 5.
Whenusing AC, check welding power source High Frequency control setting, and increase setting if nec-
essary.
Yellow powder or smoke on cup. Use proper type shielding gas.
Check for proper gas flow rate. Check manufacture’s recommendations.
Increase postflow time.
Check torch cup size. Match cup size to joint being welded.
Erratic arc When using DC, check polarity, and/or polarity of welding cables.
Whenusing AC, check welding power source High Frequency control setting, and be sure it is operating
continuously.
Select proper size and type tungsten. Properly prepare tungsten according to Section 5.
Use proper arc length. Arc length may be too long or too short.
Make sure base material is clean and free of contaminates.
When using AC, slow travel speed can cause erratic arc. Adjust travel speed.
Porosity in weld. Check for proper gas flow rate. Check manufacture’s recommendations.
Check and tighten gas fittings.
Make sure base material and filler material is clean and free of contaminates.
Check for impurities and moisture in gas lines. Purge if necessary.
If torch is water cooled, check torch and cables for water leaks. Repair or replace if necessary (see Sec-
tion 4-1).