Koike Sanso Kogyo IK-70 User manual

Portable Automatic Gas Cutter
BFB00B19
Small Circle Cutter
OPERATION MANUAL
KOIKE SANSO KOGYO CO.,LTD.
For every person who will be engaged in
operation and maintenance supervision, It is
recommended to read through this manual
before any operations, so as to permit
optimum operation of this machine.

INTRODUCTION
Thank you very much for purchasing this product. Read this instruction
manual thoroughly to ensure correct, safe and effective use of the machine.
Read the manual first to understand how to operate and maintain the
machine.
Cooperation between colleagues in the workplace is essential for safe,
smooth operation. Make sure you read, understand and take all necessary
safety precautions.
SAFETY PRECAUTIONS
This product is designed to be safe, but it can cause serious accidents if not
operated correctly. Those who operate and repair this machine must read this
manual thoroughly before operating, inspecting and maintaining the machine. Keep
the manual near the machine so that anyone operates the machine can refer to it as
necessary.
■Do not use the machine carelessly without following the instructions in the manual.
■Use the machine only after you have completely understood the contents of the manual.
■If an explanation in the manual is difficult to understand, contact our company or sales service office.
■Keep the manual to hand at all times and read it as many times as is necessary for a complete
understanding.
■If the manual becomes lost or damaged, place an order with our company or sales service office for a
new one.
■When transferring the machine to a new owner, be sure to hand over this instruction manual as well.
QUALIFICATIONS FOR MACHINE OPERATOR
Operators and repair staff of this machine must completely understand the
contents of the instruction manual and have either of the following qualifications:
1. Gas welding foremen’s license
2. Completion of gas welding training course
3. Approval by the Minister of Labor

Symbol
Title
Meaning
General
General caution, warning, and danger.
Be careful not to get your
fingers caught.
Possible injury to fingers if caught in the insertion
port.
Caution: Electric shock!
Possible electric shock under special conditions.
Ground this equipment.
Operators must ground the equipment using the
safety grounding terminal.
Pull out the power plug
from the outlet.
Operators must unplug the power plug from the
outlet when a failure occurs or when there is a
danger of lightning damage.
Caution against bursting
Possible bursting under certain conditions.
General
General warning.
Caution: Hot!
Possible injury due to high temperature under
certain conditions.
Caution: Ignition!
Possible ignition under certain conditions.

IK-70
CONTENTS
1. Safety Information 1
■WARNING 1
■CAUTION 1
■NOTICE SIGNS 1
1.1 General machine safety precautions 1
1.1.1 Machine safety 1
1.1.2 Safety clothing 1
1.1.3 Operations and handling safety precautions 2
1.1.4 Electrical system precautions 2
1.1.5 Maintenance and inspection precautions 2
1.2 Gas cutting safety precautions 3
1.2.1 Prevention of explosion 3
1.2.2 Pressure regulator safety precautions 3
1.2.3 High pressure gas cylinder safety precautions 3
1.2.4 Safety precautions for hoses 3
1.2.5 Safety precautions for fire 3
1.2.6 Safety precautions for skin burns 4
2. Locations of safety labels 5
3. Outline of machine 6
3.1 Features of machine 6
3.2 Name and function of each section 6
3.3 Specifications 7
4. Preparation for operation 8
4.1 Contents of package 8
4.2 Machine assembly 8
4.3 Preparation for operation 9
4.3.1 Connecting the power cable 9
4.3.2 Connecting the gas supply hose 9
4.3.3 Connecting the tip 9
4.3.4 Setting 9
5. Cutting operation 12
5.1 Safety measures prior to operation 12
5.1.1 Grounding the machine 12
5.1.2 Selection of tip 12
5.1.3 Operation of running direction changeover switch 12
5.2 Ignition and flame adjustment 12
5.3 Cutting and piercing method 13
5.4 Procedures for starting cutting operation and extinguishing the flame 13
5.5 Safety measures against backfire and flashback 14
5.5.1 Prevention of backfire 14
5.5.2 Prevention of flashback 14
5.6 Cutting operation 15
5.6.1 Bevel cutting 15
5.6.2 Corner cutting 15

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6. Maintenance and inspection 16
6.1 Disassembly of the machine 16
6.1.1 Daily inspection 16
6.1.2 Three month inspection 16
7. Trouble shooting 17
1) The machine will not move. (The motor will not run.) 17
2) The speed cannot be controlled. (The motor is running.) 17
3) The machine will not move.(The motor runs.) 18
4) The machine moves but the operation is not normal. 18
8. Wiring diagram 19
9. Assembly drawing of IK-70 19
10. Parts list 20
10.1 Gear unit 20
10.2 Rotary distributor unit 22
10.3 Speed adjusting unit 24
10.4 Control panel 26
10.5 Vertical-horizontal adjusting holder 28
10.6 Carriage 30
11. Cutting Data 31
102 (STANDARD SPEED) for Acetylene 31
102-D7 (HIGH SPEED) for Acetylene 31
106 (STANDARD SPEED) for Propane 32
106-D7 (HIGH SPEED) for Propane 32

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1 Safety information
Many accidents are caused by operation, inspetion, and maintenance which disregard the basic
safety rules. Carefully read, understand, and master the safety measures and precautions
described in this instruction manual and on the machine before operating, inspecting, and
maintaining the machine.
The safety messages are classified as indicated on the machine safety labels:
■WARNING
This word is used in a warning message and a warning label is positioned at places that could
cause injury or serious accident.
■CAUTION
This word is used in a caution message and a caution label is positioned at places that could cause
slight injury or machine damage. This is also used as a caution for frequent dangerous actions.
■NOTICE SIGNS
This is a sign to show machine operators and maintenance engineers items that relate directly to damage
of machines and surrounding facilities and equipment.
1.1 General machine safety precautions
Read and fully understand the following important safety information:
1.1.1 Machine safety
1.The machine casing is mainly made of aluminum alloy to reduce weight. For this reason, be careful
not to drop a heavy item on the machine, or not drop the machine when carrying it, since the alloy is
not designed to withstand such impact.
2.When mounting hoses to the torch and distributor, tighten the nut with the attached wrench. After
mounting, be sure to check there is no gas leak with a detection liquid. If a gas leak is found, retighten
the nut firmly.
3.When fixing a tip to the torch, tighten the nut with the two wrenches attached. In addition, avoid
damaging the taper part of the tip since this may cause backfire.
4.Never disassemble the machine other than during maintenance and inspection. Otherwise,
malfunction will result.
5.Never remodel the machine. Remodeling is very dangerous.
6. When changing the direction, make sure that the direction switch is in the neutral (stop) position, and
operate the direction switch after the machine has stopped.
7. Always turn the power off when not in use.
8. Never use the machine outdoors when the weather is wet. This will cause failure of the machine and
could cause a fatal accident by electric shock.
1.1.2 Safety clothing
1.Be sure to wear protector’s gauntlets, goggles, helmet, and safety shoes during operation.

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2.Avoid operating the machine with wet clothes or hands in order to prevent electric shock.
1.1.3 Operation and handling safety precautions
1. Read this instruction manual before operating the machine.
2. Mount and center the machine correctly and confirm correct motion before operation.
3. Before connecting the power plug to the outlet, make sure that the power switch is in the OFF
position (or the normal/reverse changeover switch is in the stop position).
4. Prior to operating the machine, check the safety of the surroundings to avoid accidents.
5. Never move the machine while the preheat flame is on.
6. Take great care of spatters and dross when operating the machine at a high position. They may
injure people below.
7. When it is difficult to engage the clutch, turn the rotary pipe by hand and lightly push the lever in.
Do not push the lever forcibly; otherwise the gears will be damaged, causing knocking.
8. Never disconnect the rotary distributor cover unless necessary; otherwise gas leakage will result.
9. Secure the graduated pipe to prevent it from falling.
10. Secure the vertical-horizontal adjusting holder with a curved handle to prevent the former from
falling.
11. Be sure to hold the handle when carrying the machine.
1.1.4 Electrical system precautions
1. Be sure to check the input power voltage of the machine before operation. The input power voltage
should be in the range of ±10% of the rated voltage. The machine should not be operated out of
this range.
2. The metal plugs are screw-threaded, therefore, fully tighten them so that they will not come loose
during operation.
3. Be sure to ground the power cable of the machine.
4. Stop operation and turn off the power in the following cases,
and ask a qualified electrician to repair the machine.
1)Broken or abraded cables
2)When the machine has been in contact with water, or in case of liquid damage to the machine.
3)Abnormal machine operation despite operating the machine according to the instruction manual
4)Machine breakdown
5)Poor machine performance that requires repair
5. Periodically inspect the electrical system.
1.1.5 Maintenance and inspection precautions
1. Ask a qualified electrician to perform repair and inspection service.
2. Disconnect the power plug before inspecting and repairing the machine.
3. Maintain the machine periodically.

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1.2 Gas cutting safety precautions
Strictly observe the safety rules and precautions to ensure the safety of gas cutting operations.
Operators and supervisors MUST keep safety in mind.
1.2.1 Prevention of explosion
1. Never cut pressurized cylinders or hermetically sealed containers.
2. Ensure sufficient ventilation for gas cutting to prevent the air from becoming stale.
1.2.2 Pressure regulator safety precautions
1. Before starting operation, check that all pressure regulators are operating correctly.
2. Ask a skilled repair engineer to perform maintenance and inspection service.
3. Do not use pressure regulators from which gas is leaking, nor malfunctioning pressure regulators.
4. Do not use pressure regulators smeared with oil or grease.
1.2.3 High Pressure gas cylinder safety precautions
1. Never use broken cylinders or cylinders from which gas are leaking.
2. Install cylinders upright and take measures to prevent them from falling.
3. Use cylinders only for specified purposes.
4. Do not smear container valves with oil or grease.
5. Install cylinders in a place free from heat, sparks, slag, and open flame.
6. Contact the distributor if the container valves will not open.
Never use a hammer, wrench, or other tools to forcibly open container valves.
1.2.4 Safety precautions for hoses
1.Use the oxygen hose for oxygen gas only.
2.Replace cracked hoses or other hoses damaged by sparks, heat, unshielded fire, etc.
3.Install hoses without twisting.
4.To prevent breakage of hoses, take great care during operation and transportation.
5.Do not hold the hoses when moving the machine.
6.Periodically check the hoses for damage, leakage, fatigue, loose joints, etc, to ensure safety.
7.Cut hoses to the minimum possible length. Short hoses reduce hose damage and pressure drop, as
well as reduce the flow resistance.
1.2.5 Safety precautions for fire
Take safety precautions to prevent fire prior to gas cutting.
Ignoring hot metal, sparks, and slag could cause a fire.
1.Keep a fire extinguisher, fire extinguish sand, bucket full of water, etc. ready on the site where gas
cutting is performed.
2.Keep flammables away from the cutting area to avoid exposure to sparks.
3.Always cool down steel plates that have become hot after cutting, as well as hot cut parts or scrap,
before bringing them close to flammables.
4.Never cut containers to which flammable materials are stuck.

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1.2.6 Safety precautions for skin burns
Observe the safety precautions to prevent skin burns. Ignoring heat, spatter, and sparks during
operation could cause a fire or burned skin.
1.Do not perform cutting near flammables. (Move flammables well away from the sparks.)
2.Do not cut containers filled with flammables.
3.Do not keep lighters, matches, and other flammables nearby.
4.Flames from the torch will burn the skin. Keep your body away from the torch and tip, and check the
safety before operating the switches and valves.
5.Wear the correct protectors to protect your eyes and body.
6.Correctly tighten the tip to prevent backfire.
●When fixing a tip to the torch, tighten the nut with the two wrenches attached.
●If the tip is tightened excessively, it will be heated during cutting and tightened still more, making it
difficult to remove the tip.
●Avoid damaging the taper of the tip since this may cause backfire.
7.Check with soapsuds for any leakage of gas from the connection part of the distributor, hose and
torch.
Never use oil or grease on the connection of the oxygen pipe to avoid backfire which may lead to
explosion.
8.Be sure to check the following when igniting:
●Place the torch on the torch holder before igniting.
●Always wear the required protectors (gauntlets, helmet, goggles, etc.)
●Check for any obstacles, dangerous materials and flammables near or in the direction of cutting.
Determine the gas pressure.
●The gas pressure must be within the appropriate range. (For the gas pressure, refer to the Cutting
Data.)
9.The torch, tip and heat shield are heated to a very high temperature. Always wear gauntlets when
handling them. Also the surface after cutting is very hot so do not touch it even while wearing
gauntlets.
10.Never move the machine while the preheat flame is on.

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2 Locations of safety labels
Safety labels and other labels for correct operation are affixed to the machine.
Carefully read the labels and follow the instructions on them when operating the machine.
Never remove the labels. Keep them clean and legible at all times.
IK-70 Model 600

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3 Outline of machine
3.1 Features of machine
IK-70 (Small Circle Cutter) has been engineered to ensure unprecedentedly correct and stable cutting
speed and wide speed-change range so as to materialize high-speed high-accuracy cutting effects that
meet the needs of the precision cutting age. The machine permits precision circular cutting without the
help of molds or drawings. Therefore, it exhibits excellent functions in hole making operations in the
shipbuilding industry.
IK-70 (Small Circle Cutter) has been designed on the basis of a variety of circle cutters developed in the
past, pursuing the operability from the human engineering stand point. Designed and manufactured
from a new point of view the dedicated circle cutter has a substantial lead on our competitors' similar
machines in terms of its ease of use, as well as its improved operability, durability, and cutting
accuracy. The vertical-horizontal adjusting holder that is bent and fixed permits circular cutting on a
wall and slope.
3.2 Name and function of each section
Model 600 Model 1000
1. Control box
Controls the speed and turning d e machine.
2. Horizontal arm
The horizontal adjusting arm lets the drive unit
move to the right and left.
3.Rotary distributor
4.Machine up/down unit
Moves the machine up and down. The
rack-and-pinion system ensures easy vertical
movement, preventing falling by the weight of
the unit itself. The very smooth movement
facilitates the positioning of steel sheets and the
center. When the machine is to be used for
cutting on a slope, the bolt on the connection
section will be loosened to match the machine
angle to the steel sheet angle.
5. Torch
6. Hose
7.Leg (Model 600) (Free opening/with caster)
The legs are light and easy to carry. They can be
opened up to 90 degrees according to the
cutting size. The casters make the movement on
steel sheets smooth. When secured with three
bolts during cutting, the legs will never move.
8.Stand (Model 1000)
9.Weight (Model 10OO)
10. Clutch
Changes over from high-speed to low-speed,
and vice versa.

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3.3 Specifications
Model 600
Weight: 24 kg
Body: 17kg
Stand: 7 kg
Power source: ±10%
Speed control: control with dial operation
Torch rotation speed: 0.2-6 rpm
Cutting thickness: 5～50 mm
※There is a range that cannot be cut depending on the relationship between cutting thickness
and cutting diameter.
Please check “Relationship between the cutting plate thick ness and cutting diameter.”
Bevel angle: 0-45°
Cutting diameter: φ30 ～φ600
Motor: DC Motor 15W 5000rpm (DC24V)
Slope cutting angle: 0-90°
Tip: 102 (for acetylene) or 106 (for propane)
Gas: Oxygen, Acetylene gas, or LPG gas
Model 1000
Weight: 55 kg
Body: 31 kg
Stand : 9 kg
Weight: 15kg
Power source: ±10%
Speed control: control with dial operation
Torch rotation speed: 0.04-1.5 rpm
Cutting thickness : Cutting thickness: 5～50 mm
※There is a range that cannot be cut depending on the relationship between cutting thickness
and cutting diameter.
Please check “Relationship between the cutting plate thick ness and cutting diameter.”
Bevel angle: 0-45°
Cutting diameter: φ150 ～φ1000
Motor: DC Motor 15W 5000rpm (DC24V)
Slope cuffing angle: 0-90°
Standard accessories
Tip 102 (for acetylene) or 106 (for propane)
No.0,1,2 1pc each
Tip cleaner: 1set
Fuse(1A): 2pcs
Power cable: 1pc

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4 Preparation for operation
4.1 contents of package
The contents of the standard package are shown below. Check them carefully before assembling the
machine.
Body: 1 set
Gas distributor: 1 set
Torch holder: 1 set
Torch: 1 Pc
Hose
Distribution hose (3pcs set: 600L): 1 set
Power cable (3P x 5M): 1 set
Tip 102 (for acetylene) or 106(for propane): 1 pc each
Tip cleaner: 1 set
Fuse (1A): 2pcs
4.2 Machine assembly
Model 600
1. Take out the machine and legs from the packing box.
2. Open the legs and insert the main shaft into them. Secure the main shaft with a wing bolt (M8 x 25).
3. Carefully check that the torch holder, gas distributor, torch, etc. are in position.
4. Check the match marks.
1) Marks on the vertical-horizontal adjusting holder and horizontal arm adjusting holder.
2) Marks on the graduated pipe and torch holder
When marked lines coincide, the horizontal and vertical positions of the machine are perfect.
Model 1000
Model 1000 is packed in three carton boxes. Unpack respective carton boxes to take out the respective
parts.
Machine assembly 1 pack
Carriage assembly 1 pack
Weight assembly 1 pack
1. Take out the machine, carriage, and weight from the boxes.
2. Place the carriage on a flat floor and put the carriage and weight together with two bolts (M10 x 35).
3. Insert the main shaft into the carriage and secure it with a wing bolt (M8 x 25).
4. Check the match marks.
1) Marks on the vertical-horizontal adjusting holder and horizontal arm adjusting holder.
2) Marks on the graduated pipe and torch holder
When marked lines coincide, the horizontal and vertical positions of the machine are perfect.

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4.3 Preparation for operation
4.3.1 Connecting the power cable
1. Connect the power cable to the body.
2. Before plugging the metal plug on the power cord side into the socket on the machine side, check
there is no dust inside.
3. The metal plugs are screw-threaded, therefore, fully tighten them so that they will not come loose
during operation.
4.3.2 Connecting the gas supply hose
1. Connect the respective gas supply hoses to the primary hose.
2. Securely tighten the joints and check there is no gas leak.
4.3.3 Connecting the tip
1. Select a proper tip according to the thickness of the steel plate and attach it to the torch.
(To select a tip, refer to the table of cutting data.)
・When fixing a tip to the torch, tighten the nut with the two wrenches attached.
・If the tip is tightened excessively, it will be heated during cutting and tightened still more making it
difficult to remove the tip.
・In addition, avoid damaging the taper of the tip since this may cause backfire.
4.3.4 Setting
1. How to determine the cutting diameter
1) The graduation on the graduated pipe represents the
diameter of cutting circles. The datum point for aligning the
graduation is the arrow on the holder.
2) Calculate the cutting width of the tip.
(The cutting width is 1.5-2.0 times as large as the cutting
oxygen hole diameter.)
[Example]
When the sheet is 20 mm in thickness and 200 in dia. (Tip 102).
The cutting tip is #2 according to the Cutting Data, and the oxygen cutting hole dia. of the
#2 tip is 1.4.
The cutting allowance is 1.4mm x 1.5 = 2.1
When the cut disc is needed, the graduation will be 200 dia.+ 2.1mm = 202.1 dia.
When the cut hole is needed, the graduation will be 200 dia.- 2.1mm = 197.9 dia.
Set the stopper at the above values.
3) Stopper setting
The stopper to be used
when the cut disc is needed
(outside cutting) and that to
be used when the cut hole is
needed (inside cutting) are
different. Set the stopper as
shown right.
Datum
Outside
cutting
Inside
cutting

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2. Set the clutch lever in the N (neutral) position, turn the graduated pipe by hand, and adjust the leg
opening angle and the horizontal arm length so that the torch and hoses will not touch the legs and
shaft column.
3. Align the center with the punched mark. Operate the machine up/down unit so that the center will
lightly touch the steel plate.
(Lift the center so that the distance between the Center and steel plate will be 0.5-1.0 mm.)
4. Secure the curved handle on the machine up/down unit.
5. Secure the machine with the lock bolt on the leg so that the machine will not move.
6. Setting the cutting speed
The cutting speed (number of revolutions) differs according to the diameter of the cutting circle and
the sheet thickness.
1) Find the optimum cutting speed for the given sheet thickness based on the Cutting Data.
2) Find the correct clutch -- H(high-speed) and L(low-speed) -- and the number of revolutions based
on the table that shows the relationship between the cutting plate thickness and cutting circle.
3) Set the number of revolutions by means of the speed adjustor.
Relationship between the cutting plate thickness and cutting diameter (Model 600)
L (low-speed) range
Thickness(mm)
5
5-10
10-15
15-30
30-40
40-50
50-
Cut speed(mm/min)
660
550-660
490-550
400-490
350-400
320-350
200-320
Cut diameter φ50
Not use
Not use
Not use
Not use
Not use
Not use
1.3
φ60
Not use
Not use
Not use
Not use
Not use
Not use
1.0
φ70
Not use
Not use
Not use
Not use
Not use
1.4
0.91
φ80
Not use
Not use
Not use
Not use
1.4
1.3
0.79
φ90
Not use
Not use
Not use
1.4
1.2
1.1
0.71
φ100
Not use
Not use
Not use
1.3
1.1
1.0
0.64
φ200
1.0
0.87
0.79
0.64
0.56
0.51
0.32
φ300
0.70
0.58
0.52
0.42
0.37
0.34
0.21
φ400
0.52
0.44
0.39
0.32
0.28
0.25
Not use
φ500
0.42
0.35
0.31
0.25
0.22
0.20
Not use
φ600
0.35
0.29
0.26
0.21
Not use
Not use
Not use
Numbers in the thick line frame: Rotation speed (rpm)
H (high-speed) range
Thickness(mm)
5
5-10
10-15
15-30
30-40
40-50
50-
Cut speed(mm/min)
660
550-660
490-550
400-490
350-400
320-350
200-320
Cut diameter φ30
Not use
5.8
5.3
4.2
3.7
3.4
2.1
φ40
5.2
4.4
3.9
3.2
2.8
2.5
1.6
φ50
4.2
3.5
3.1
2.5
2.2
2.0
Not use
φ60
3.5
2.9
2.6
2.1
1.8
1.7
Not use
φ70
3.0
2.5
2.0
1.8
1.6
Not use
Not use
φ80
2.6
2.2
2.0
1.6
Not use
Not use
Not use
φ90
2.3
1.9
1.7
Not use
Not use
Not use
Not use
φ100
2.1
1.7
1.6
Not use
Not use
Not use
Not use
Numbers in the thick line frame: Rotation speed (rpm)

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Relationship between the cutting plate thickness and cutting diameter (Model 1000)
L (low-speed) range
Thickness(mm)
5
5-10
10-15
15-30
30-40
40-50
50-
Cut speed(mm/min)
660
550-660
490-550
400-490
350-400
320-350
200-320
Cut diameter φ150
Not use
Not use
Not use
Not use
Not use
Not use
0.42
φ200
Not use
Not use
Not use
Not use
0.56
0.51
0.32
φ300
Not use
Not use
0.52
0.42
0.37
0.34
0.21
φ400
0.52
0.44
0.44
0.32
0.28
0.25
0.16
φ500
0.42
0.35
0.31
0.25
0.22
0.20
0.13
φ600
0.35
0.29
0.26
0.21
0.18
0.17
0.10
φ650
0.32
0.27
0.24
0.19
0.17
0.16
0.10
φ700
0.30
0.25
0.22
0.18
0.16
0.14
0.09
φ800
0.26
0.22
0.20
0.16
0.14
0.13
0.08
φ900
0.23
0.19
0.17
0.14
0.12
0.11
0.07
φ1000
0.21
0.17
0.16
0.13
0.11
0.10
0.06
Numbers in the thick line frame: Rotation speed (rpm)
H (high-speed) range
Thickness(mm)
5
5-10
10-15
15-30
30-40
40-50
50-
Cut speed(mm/min)
660
550-660
490-550
400-490
350-400
320-350
200-320
Cut diameter φ150
1.4
1.2
1.0
0.85
0.74
0.68
0.42
φ200
1.0
0.87
0.79
0.64
0.56
0.51
0.32
φ300
0.70
0.58
0.52
0.42
0.37
0.34
0.21
φ400
0.52
0.44
0.39
0.32
0.28
0.25
0.16
φ500
0.42
0.35
0.31
0.25
0.22
0.20
Not use
φ600
0.35
0.29
0.26
0.21
0.18
0.17
Not use
φ650
0.32
0.27
0.24
0.19
0.17
0.16
Not use
φ700
0.30
0.25
0.22
0.18
0.16
Not use
Not use
φ800
0.26
0.22
0.20
0.16
Not use
Not use
Not use
φ900
0.23
0.19
0.17
Not use
Not use
Not use
Not use
φ1000
0.21
0.17
0.16
Not use
Not use
Not use
Not use
Numbers in the thick line frame: Rotation speed (rpm)
7. Release the center as shown below when the cutting diameter range is 30-100.

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5 Cutting operation
5.1 Safety measures prior to operation
5.1.1 Grounding the machine
The cable of this machine is equipped with a grounding wire. For safety, be sure to ground the wire as
follows, in addition to checking the connection of the power cable.
■How to ground the machine
5.1.2 Selection of tip
Referring to the Cutting Data, select the suitable tip according to the plate thickness.
For a heavily rusted plate or for a bevel cutting of more than 20 degrees, select the tip one grade higher
than the one shown in the Cutting Data.
5.1.3 Operation of running direction changeover switch
Use the drive switch to change the direction of rotation (clockwise-counterclockwise). The machine
is at rest when the switch is in the neutral position.
When changing the direction of rotation, be sure to return the drive switch to the stop (neutral)
position. After the machine has stopped, change the direction of rotation.
Be sure to set the switch in the stop (neutral) position unless the mac is to be moved.
Set the drive switch in the stop (neutral) position when turning on the power. When the switch is in
the clockwise or counterclockwise turning position, the machine will begin to move, which is very
dangerous.
5.2 Ignition and flame adjustment
Adjust the gas pressure according to the Cutting Data. The data shows the pressure when all the valves
are open. Readjust the pressure after ignition.
■Flame adjustment method
1. Open the fuel gas valve 1/4 to 1/2 a turn, and light the torch with an igniter.
2. Then, open the preheating oxygen valve gradually until a white cone of the standard flame gas been
obtained. (The incandescent area should be uniform and about 5-6 mm in length.)
3. Open the jet oxygen valve fully. Readjust the flame if its condition has changed. A disorderly flow of
the jet oxygen will adversely affect the quality of the cutting surface. In such a case, clean the tip with
a suitable cleaning needle while the jet oxygen is flowing.
・The ground pin is attached to the rubber plug of a cabtyre cord. Please use a power receptacle with
a ground pin opening.

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4. Appropriate distance between the tip end and cutting surface:
・Acetylene gas 8-10 mm
・LPG gas 5-8 mm
Neutral flame ensures good quality cut surfaces. (Oxygen flame may be used for bevel cutting.)
Oxygen flame causes short cutting-oxygen current, allowing slugs to adhere, melting the upper edge of
the cutting surface, and causing adverse effects on the cut surface. Similar defects will result when the
cutting oxygen pressure is too high.
(1)Oxidizing Flame
(2)Neutral Flame
(3)Carbonizing Flame
5.3 Cutting and piercing method
1. Cut in from the end of steel plate.
2. Pierce steel plate before cutting.
3. Drill a hole before cutting.
■Piercing method
1) Ignite and adjust the flame.
2) Thoroughly preheat the cut-in point until it is white hot.
3) Open the cutting oxygen valve to pierce the steel plate. The tip should be about 15-20 mm from the
plate to prevent slag from splashing onto the tip and adhering there, which will shorten the working
life of the tip.
5.4 Procedures for starting cutting operation and extinguishing the flame
1. Align the tip with the cutting start point, ignite, and then adjust the flame.
2. Sufficiently preheat the cutting start point.
3. After sufficient heating, let the cutting oxygen out and begin cutting simultaneously by turning the
graduated pipe feed handle.
4. Turn on the switch or engage the clutch right before the graduated pipe strikes against the stopper,
and continue cutting up to the stopper position.
5. Extinguish the flame after cutting as follows:
1) Turn off the motor switch (or turning direction switch).
2) Close the cutting oxygen valve.
3) Close the preheating oxygen valve.
4) Close the fuel gas valve.

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5.5 Safety measures against backfire and flashback
5.5.1 Prevention of backfire
Backfires may cause serious accidents or fires. Be careful to prevent such disaster. When a backfire
occurs, find the cause and inspect and maintain the machine correctly before using the machine again.
The followings are causes of backfire:
1) Improper gas pressure adjustment
2) Overheated tip
3) Slag clogged in tip
4) Damage to the tapered section of the tip or torch will cause backfire.
5.5.2 Prevention of flashback
Flashback could cause fire and break the machine. Should there be a hissing sound in the torch, quickly
take the following action:
1) Close the preheating oxygen valve.
2) Close the fuel gas valve.
3) Close the cutting oxygen valve.
Should flashback occur, find the cause and take appropriate action before using the machine again.