34
Dehaco B.V. • Kruisbaak 25 • 2165 AJ Lisserbroek (NL) •
✆
+31 (0)252 - 41 79 50 •
[email protected] • www.dehaco.nl
Appendix-1 Underwater operation
APPENDIX-1 UNDERWATER
OPERATION
All of the IBEX breakers are suitable for underwater
operations. An underwater kit must first be mounted
to the breaker to ensure safe and continuous breaking.
This kit is not included as standard with the breaker
but is readily available and easily mounted to the
breaker and excavator.
Whilst breaking underwater the impact area between
the piston and tool will fill with water. The volume of
the water is equal to the stroke length of the piston
plus the stroke length of the tool. During impact
enormous forces are applied to the water that can
only be relieved via the clearance between the tool
and bush. This water is discharged at an extremely
high pressure and velocity that can be injected into
the breaker itself.
Although the breaker is completely sealed without
this underwater kit it is possible that water could
enter the breaker and therefore the excavator causing
catastrophic damage. Due to the extreme conditions
that are applied to the breaker whilst operating
underwater this kit is essential.
IBEX models 170GS to 900GS have an air connection
mounted directly on the front head. Whilst models
1200GS to 4000GS have an elevated and safer
mounting point on the backhead. This prevents
possible damage to air hoses and connections. In turn
reducing the possibility of damage to the breaker and
therefore down time.
A-1.1 Compressor Capacity
Whilst breaking underwater compressed air must be
applied to ensure safe operation. The volume of air
required varies dependent on the type of breaker.
This information is available per model from Dehaco
or an approved Dehaco dealer. The standard pressure
required for all models is between 3 - 5 bar (32-72
psi).
Setting the supplied air pressure is also dependent on
the working depth of the breaker.
◊ 2 Bar should be added per 10 meter depth
-
I.e. 10 meter, 3-5 bar + 2 bar = 5-7 bar
◊ Flow is dependant on model
Procedure for supplied air pressure setting:
1) After installation of the underwater kit, operate
the compressor to supply the air to the breaker
before it is submerged in the water. Maintain the
air pressure with the regulator during this period.
2) Submerge the breaker to the maximum working
depth for that particular work. Before operating
the breaker ensure that bubbles are visible from
the tool of the breaker.
3) Whilst maintaining the aforementioned condition,
reduce the air pressure gradually with the
regulator and set the supplied air pressure to the
required level.
4) Warning – Do not supply the compressed air at full
power directly to the breaker. Otherwise air may
be injected into the sealed area of the breaker.
Ensure that the compressed air always passes
through the regulator.
A-1.2 Operation
Operate the breaker with great care underwater
because it is exposed to the severe conditions of the
water.
1) When using a breaker that has been stored for
a long term, ensure that the lubricating oil is
removed from the clearance between the tool and
bushes prior to operation.
2) Supply the compressed air to the underwater kit.
3) Only operate the breaker once the air pressure has
reached the required pressure.
4) Submerge the breaker in the water.
5) Stop breaking immediately if the air supply
has been broken during operation. Determine
the cause and reinstate the air supply before
continuing.
6) Do not break in the same position for a long time.
7) In the case that the excavator is mounted on a
barge, the tool is liable to break because of the
instability of the barge.
8) The tool must be greased more often than during
normal operation due to the severe conditions of
the water and air combined.
