Underwater Wet Welding Products Operating - Broco

Underwater Wet Welding Products Operating - Broco
BROCO® Inc.
400 S. Rockefeller Ave.
Ontario, CA 91761 USA
(909) 483-3222
(909) 483-3233 Fax
(800) 845-7259
Underwater Wet Welding Products
Operating Instructions
Product Warnings
WARNING
Please read and understand these operating instructions thoroughly and follow the procedures contained
herein before attempting to use Broco Underwater Wet Welding products. Failure to do so can result in
death, serious injury, property damage and poor welding performance.
All personnel and supervisors engaged in underwater welding operations must be familiar with these
instructions, the correct use of underwater welding equipment, and accepted safe commercial diving
practices. Employers must provide operator training before allowing their personnel to begin using Broco
Underwater Wet Welding products.
CAUTION
Underwater cutting & welding equipment is potentially dangerous to operate and must be used in strict
accordance with the instructions provided. Underwater cutting & welding should only be performed by
trained professional commercial divers and according to industry accepted safe diving practices.
WARNING
Never modify this equipment in any manner or use it in any way not specified in these instructions.
Always adhere to ANSI/ASC Z49.1:2012 “Safety in Welding and Cutting” standards, or similar locally
prevailing standards when using this equipment.
Always follow industry accepted safe diving practices as found in the Association of Diving Contractors
“Consensus Standards for Commercial Diving.”
Always use surface supplied breathing air and hard-wire communications. Never conduct underwater
cutting or welding while using self-contained breathing apparatus (SCUBA).
Never conduct underwater cutting or welding operations without a topside tender to monitor the diving
operation and a standby diver for emergency response.
Never use life support equipment that has been altered or modified from the manufacturer’s original
specifications.
Never use any equipment that is unsafe or appears to be unsafe. Always replace damaged or worn
components to reduce the risk of injury.
Always be aware of material that may fall and position yourself and your life support equipment
accordingly.
Never use alternating current (AC) for any underwater operation.
Always ensure only direct current (DC) from a known power source goes into the water.
Always have electrical power to the welding electrode holder routed through a safety knife switch that must
be located within reach of the topside tender.
Never use this equipment without proper eye protection. Always use an approved welding lens with a shade
appropriate for the conditions of the water.
WARNING
Failure to heed these safety precautions may result in severe property damage, bodily injury or death.
Protect yourself and others. Explosive gas mixtures may be generated. Arc rays can injure eyes and
exposed skin. Electric shock can kill.
Safety Precautions
WELDING POWER SUPPLIES
Welding power supply equipment should be
operated according to the procedures and
precautions specified by the welding power supply
manufacturer in addition to the safety precautions
listed below.
1. Always use a welding power supply with DC
output only. Never use a welding power supply
that can be switched to AC output when
underwater welding. AC current in the water can
kill a diver.
2. Make sure that the welding machine frame
and its supporting structure are well grounded
before starting operations.
3. Make certain that neither terminal of the
welding machine is short-circuited to the
machine frame before starting operations.
4. Make sure that all electrical connections are
securely made before starting operations.
5. Always wear rubber or rubberized-canvas
electrical insulating gloves that are in good
condition when handling energized holders,
cables or machines.
ELECTRODE HOLDERS
1. Use only electrode holders specifically designed
for underwater use. They must be rated for the
maximum current required for the electrodes
used. Broco’s BR-20 and BR-21 electrode holders
are recommended.
2. Make sure that all current-carrying parts of the
holder are fully insulated. This insulation must
safely protect the diver against the maximum
current encountered.
3. Inspect the electrode holder for worn or
damaged parts and insulating material before
starting operations. Damaged parts may
endanger life and must be replaced immediately
before further use.
4. Change or tighten the electrode only when
there is no current flowing in the welding circuit.
5. Never hold the electrode holder so that it points
toward you.
6. Special care should be taken to avoid touching
the metal on the diving gear with the electrode,
or with uninsulated parts of the electrode holder,
or with the work.
POWER CABLES AND CONNECTORS
1. All parts of surface cables and submerged cables
must be fully insulated.
2. Inspect all cables and connections for damaged
insulation before starting operations. The cables
must be replaced or the defects repaired before
starting operations.
3. Cables must have the capacity to handle the
maximum current requirements for the work.
Cable connectors must have a capacity at least
equal to that of the cable.
4. All connections must be made tight and
thoroughly insulated. All underwater
connections should be given a final tight
wrapping of rubber tape to prevent current loss.
5. Make sure all cables are free of splices for at least
the last ten feet from the connections to the
electrode holder and the ground.
6. Always connect the ground directly to the
material being welded as close to the point
of welding as possible. Never use an in-water
floating ground.
7. Always face the ground connection while
welding. Never position the diver between the
ground and the welding electrode.
8. Do not allow the power supply power cable to
get entangled with welding cables. Keep the
two separated.
SAFETY SWITCH
1. The safety switch must be mounted vertically
and with the handle in the upper-most position
during welding. If the switch handle should
accidentally fall, the circuit is broken (no current).
2. Always ensure the safety knife switch is in the
open position (no current) before starting the
welding power source.
3. Always keep current off at all times except when
welding.
4. Do not operate the safety knife switch in a
combustible atmosphere.
5. The safety switch should be within easy reach of
the tender at all times.
GENERAL SAFETY PRECAUTIONS
When welding or cutting into a closed or blind
compartment, keep in mind that explosive gases
can develop. These gases must be vented to
remove the possibility of an explosion.
Oxygen and hydrogen are generated from the
electrode flux and from the water. These gases
will explode if trapped and ignited. They can
collect in pipelines, manifolds, compartments and
structures such as “H” beams. It is important that
compartments are vented because sparks from
cutting or welding contained in bubbles can rise
several feet and cause trapped gases to explode.
Operating Instructions
NOTE: Broco SofTouch and Broco EasyTouch wet welding electrodes, are to be welded using DC
current, straight polarity (electrode negative).
EQUIPMENT LIST FOR UNDERWATER WELDING
1. A welding machine that produces only direct
current
2. A knife switch rated at 400 amperes, 250 volts
3. Welding cables size 2/0 or as appropriate for the
amperage and circuit length
4. Cable connectors
5. Electrode holder
6. Electrodes
7. Grounding clamp
8. Weighted wire brush
9. Chipping hammer
10. Scraper
11. Tong meter for measuring amperage (optional)
12. Personal protective equipment to include
gloves, protective lenses, appropriate diver’s
dress
400 amp Safety
Switch (not to
scale)
ELECTRODE
GROUND
To electrode
holder
Ground Cable
to be clamped
to part of metal
to be welded
DC Welding Generator
UNDERWATER WELDING EQUIPMENT ARRANGEMENT FOR
STRAIGHT-POLARITY DIRECT-CURRENT OPERATION
METHOD FOR VERIFYING STRAIGHT POLARITY
1. With the welding machine switch in the off position, connect the safety knife switch jumper cable to
the negative terminal of the welding machine, the electrode holder power cable to the safety knife
switch, and the ground cable to the positive terminal of the welding power source.
2. Clamp an electrode to the ground cable and insert another electrode into the electrode holder.
3. Place the ends of the two electrodes in a container of salt water, keeping the tips about two inches
apart.
4. Be sure that the operator is properly insulated, turn the welding power on and close the safety knife
switch. Bubbles will flow from the negative (-) pole to the positive (+) pole. A very little amount of
bubbles will be generated from the positive (+) electrode.
5. The polarity of the system is set correctly if the greatest amount of bubbles rise from the electrode
secured in the welding electrode holder. If more bubbles are coming from the electrode in the
ground clamp the cable connections at the welding machine terminals must be reversed.
Recommended current settings are listed in Table 1. The amperage values are averages and sample welds
should be made and inspected to adjust the settings for specific conditions.
TABLE 1
CATALOG NUMBERS
DIAMETER
INCH
MM
UW/CS-1 & UW/EZ-1
1/8
3.20
UW/CS-2 & UW/EZ-2
5/32
UW/CS-3 & UW/EZ-3
WET WELD APPLICATION
CURRENT SETTINGS (AMPS)
FLAT
HORIZONTAL
VERTICAL
OVERHEAD
MILD STEEL
160-170
150-170
140-165
140-160
3.97
MILD STEEL
180-210
170-210
170-210
170-190
3/16
4.76
MILD STEEL
250-280
240-280
240-280
235-275
UW/SS-1
1/8
3.20
STAINLESS STEEL
135-150
130-150
125-145
125-145
UW/SS-2
5/32
3.97
STAINLESS STEEL
150-200
140-200
140-190
140-180
UW/SS-3
3/16
4.76
STAINLESS STEEL
175-250
165-250
165-240
165-235
EQUIPMENT ASSEMBLY
1. With the welding machine switch in the off position, connect the safety knife switch jumper cable to the
negative terminal of the welding machine, the electrode holder power cable to the safety knife switch,
and the ground cable to the positive terminal of the welding power source.
2. Set the welding machine to straight polarity. Verify correct polarity: negative (-) to holder; positive (+) to
ground.
3. Determine the amperage setting and check it with a tong meter or an ammeter.
4. Completely insulate all cable connections.
5. Make sure that cables and connections are in good operating condition, and that all cable within ten
feet of holder is free of splices.
6. Secure ground clamp to work.
Welding Techniques
Two techniques are in use: the “self-consuming” or
“drag” technique and the “manipulative” technique.
With the self-consuming technique, the electrode
is dragged across the work with a slight amount
of pressure applied to the contact surface. In
the manipulative technique, the arc is held as it
would be on the surface, and little or no pressure
is applied to the electrode, which is continually
woven from side to side by the diver welder. This
technique requires much more skill than the
self-consuming method.
SELF-CONSUMING TECHNIQUE
Using the self-consuming method, the weld metal
is deposited in a series of beads by dragging the
electrode, which is melting, against the work.
Typically fillet weld beads result in welds of
approximately the same leg size as the diameter
of the electrode used. For example, a single pass
with a 5/32” electrode produces a fillet weld having
5/32” legs.
FILLET WELDING IN THE HORIZONTAL POSITION
1. Make sure the safety switch is open (off ).
2. Thoroughly clean the surfaces to be welded.
3. Set the welding machine to deliver the proper
current according to Table 1. Check the
delivered current with a tong meter or fixed
meter.
4. Place the striking end of the electrode against
the work so the electrode is at an angle of about
30 degrees to the line of weld. This angle may
vary from 15 degrees to 45 degrees, depending
on electrode type and individual’s preference.
5. At the diver’s call for “switch on” the safety knife
switch is closed, energizing the circuit. Tap the
end of the electrode against the work until the
arc forms, making sure the electrode is at the
point where the weld is to begin. In some cases
it may be necessary to scrape the tip before
inserting the electrode in the holder. Exert
enough pressure against the work to allow the
electrode to consume itself. Do not hold an arc
as in topside welding. Keep the electrode in
contact with the work, maintaining the original
angles between the work and the electrode.
Run straight beads – do not weave. About eight
inches of weld is deposited for every fourteen
inch electrode consumed.
6. When the electrode is consumed, the diver calls
for “switch off”. The tender must then open
the safety switch and keep it open while the
electrode is being changed. Keep the electrode
in the welding position after completing the
weld until verification of “switch off” is received
from the tender.
7. Before welding with a new electrode, clean the
end of the old deposit. If a second pass is to be
made on top of the initial deposit, the previously
deposited weld must be cleaned.
8. Do not call for “switch on” until the new
electrode is in position and against the work and
ready for welding.
FILLET WELDING IN THE VERTICAL POSITION
Follow the same steps outlined above for horizontal
fillet welding. The weld must start at the top and
move down so that the bubbles generated will not
interfere with the diver’s vision as he follows the
line of the weld. In the vertical position it may be
necessary to vary the angle of the electrode to the
work and adjust the current, to obtain the optimum
weld.
FILLET WELDING IN THE OVERHEAD POSITION
Use the same procedures as described in the
previous paragraph. The range of current is
relatively narrow for the overhead position. Before
making an actual weld, the diver should make
several practice passes under actual working
conditions. These welds should be brought topside
and examined to determine whether the current
setting is correct and the diver’s technique is good.
Dripping beads indicate that:
(1) The current was too high
(2) Insufficient pressure was applied
(3) Both conditions were present
MANIPULATIVE TECHNIQUE
This method requires the welder to maintain a
constant arc under water while maneuvering the
electrode. It can be used to apply straight beads as
well as beads with a slight to significant weave. The
weave must be very tight to avoid slag entrapment.
To use this technique, the proper amperage and
electrode type should be determined by testing a
sample plate under wet working conditions. The
correct position of the electrode and speed of
travel should also be determined before beginning
the actual weld.
The amperage settings will be the same as those
described for the self-consuming technique,
though the adjustment is over a narrower range.
Proper current settings can be identified by looking
for the same “puddle” characteristics as in topside
welding.
WELDING POSITIONS
The procedures described above for horizontal,
vertical and overhead welding using the selfconsuming technique are applicable to the
manipulative technique. Working conditions
such as visibility, water depth, joint fit-up, and
magnetism buildup in the base metal will affect the
electrode angle, manipulation of the electrode and
maintenance of the arc.
The manipulative method has some advantages
over the self-consuming method. With the
manipulative technique, vertical welding can be
performed upwards. If the joint fit-up is poor and
the opening is more than 1/8 inch a vertical up
progression can be used with a weave to fill the
gap and obtain full root penetration. Vertical up
welding is also used to reduce the magnetic fields
which tend to build up at the bottom of joints
after a number of vertical down passes. To reduce
the buildup, the lower three inches of the joint are
deposited using vertical up welding, then welding
the remainder of the joint by vertical down welding
to tie in with the initial three inches.
In multi-pass welding, current settings must be
changed as passes are added. Correct settings are
obtained by running test beads prior to the actual
weld.
Please call the Broco Sales and Customer
Support staff at (909) 483-3222 with any
questions.
Broco, Inc.
400 S. Rockefeller Ave.
Ontario, CA 91761 U.S.A.
Toll-free: (800) 845-7259
P: (909) 483-3222
F: (909) 483-3233
[email protected]
www.brocoinc.com
© Copyright 2017 by Broco, Inc., all rights reserved. Any
reproduction in whole or in part without the express
written permission of Broco, Inc. is prohibited.
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