Diesel - Hydraulic Clamshell Grab Type DHS-B 8,0m³

Technical Description
Diesel - Hydraulic Clamshell Grab
Type DHS-B 8,0m³
radio - controlled
Diesel grab offer DHS-B 8.0 m3, AH 6065, tech. description
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General
The below described radio - controlled Diesel - hydraulic clamshell grab is a modern
an robust high - performance bulk - handling machine.
The grab consists mainly of the following components:
1. Centre Grab Section with
- Diesel engine and flanged - on variable axial hydraulic piston pump
- Hydraulic - tank with integrated fuel - tank
- Double - arm vertical support with mounted cross member and chain support
- the radio - control receiver unit with connected electric controls motor electric
and battery
- the two hinged covers for the complete drive
- the bearing points for the two working cylinders
- the four bearings for the clamshell bolts at the bottom side
2. Two double - acting hydraulic cylinders with cover
3. Clamshells with
- sealed joint bearings in the clamshell - turning points
- the bearings for the working cylinders
- the lateral working cylinder protection in the centre of the clamshell, what is the
slide - way for the working cylinder - cover at the same time
After being hooked into the crane the grab is ready for operation.
The functions:
- Diesel engine " Start "
- Diesel engine " Stop "
- Grab " Open "
- Grab " Close "
are radio - controlled by the crane driver via the mobile transmitter in the crane cabin.
The control of the grab can also be done by a man near the ship’s hatch if the grab is outside
of the crane driver’s range of view.
The max. transmitting range is approx. 200 m.
The compact construction design in combination with a suitable arrangement of all components
and the optimised grab kinematics are resulting in:
- a suitable course of the grab closing forces (especially at the end of the closing
process high closing forces are ensured)
- an wide grabbing distance between the shells
Additionally there is a good filling of the grab due to the suitable shell shape and grab
curves.
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A high utilisation of the crane’s lifting capacity and therefore an optimised load turn -
over is guaranteed due to the minimised dead weight of the grab in combination with the
designed grab volume and load capacity.
The mechanical stability is guaranteed by a homogeneous construction, ample dimensioned
components and a good welding workmanship.
Centre Grab Section
The centre grab section consists of a sturdy, welded steel construction made of high tensile
steel quality St 52-3. It functions simultaneously as hydraulic tank with top-mounted
fuel tank, support for the clamshells and bearing point for the working cylinders.
The diesel - hydraulic drive unit is installed protected by foldable covers, the exhaust pipe
unit is mounted at the outside.
To avoid the exhaust pipe unit from the vibrations of the diesel engine a flexible pipe made
of stainless steel is installed between the exhaust bend and the exhaust pipe.
The fuel store is sufficient for a single - shift working day.
The cross-member with shackle and chain is bolted to the vertical support arms.
Drive Unit
The drive unit consists of the diesel engine with directly flanged variable axial hydraulic
piston pump. The complete unit is mounted onto the tank-top of the centre grab section.
Diesel engine : Type KHD Deutz / Kubota
Axial piston pump : Make Rexroth - Hydromatic or equal
The hydraulic control valve, necessary remote control valves and remaining fittings are
mounted on the top of the hydraulic - tank.
Radio Control Unit
Type : 4- Channel with German FTZ - Certificate
The following functions are controlled via this mobile radio unit:
- Diesel engine " Start "
- Diesel engine " Stop "
- Grab " Open "
- Grab " Close "
The receiver is mounted protected on the centre grab section below the foldable covers;
the antenna is mounted at the outside of the centre machine unit.
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Hydraulic cylinders
Double - acting hydraulic cylinders with sea - water - resistant nickel - chrome - plated piston
rods. The cylinders are protected against bulk a.s.o. by steel covers.
Clamshells
The grab clamshells are of a welded, stiff steel construction with solid designed bearings
to be connected to the main power section and to the hydraulic cylinders.
A pipe of a large diameter is installed across to the clamshell upper section and both yoke
plates, which are descending from the clamshell to the grab arm bearing point.
This thick walled pipe is additionally stiffening the clamshell - side plates and provides a
high constructive twist resistance.
The bottom- and side - plates are of steel quality St 52 - 3.
The clamshell bearings are arranged rearwards, in order to enable the grab gripping into
the areas underneath the top wing tanks of the vessel. The knives are a massive construction
of highly wear resistant steel type HARDOX400 (or similar quality). For an additional
price standard type clamshell - teeth (choice of owner) are available.
Bolts
- Bolt clamshell - cylinder and case : X20Cr13
- Bolt clamshell - case : 42CrMo4
Bearings
Clamshell connection to main power section and cylinders:
Sealed joint bearings with additional sealing
Lubrication
Each bearing point is provided with an individual lubrication bore, witch ensures that all
bearing points can be checked with regard to proper grease passing.
Lubrication nipples: countersunk mounted high pressure nipples of DIN - type 71 412
General remark
All components are easily accessible and dismountable. Screws, axles, supports a.s.o. are
DIN - standard type as far as possible.
Connecting parts made from stainless steel (A4).
Coatings
Sandblasted SA 2,5
First coat : Primer
Top coat : synthetic resign vanish
Colours : yellow RAL 1004
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DATE:
CONTR:
REF. :
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G
T
S a f e wor ki ng Load ( SWL) = 32 t
P r üf l ast ( Test l oad) = 59 t
CONSTR. / DRAW.:
STAND. CONTR.::
TRACED:
APPROVED:
CALC.:
SCALE:
0 9.0 4 . 9 8 Krebs 1/5
PROJ. METH.:
O R T S G m b H M a s c h i n enfabrik
D 2 3 6 1 1 S e r e e t z
Phone: 0451 / 398850 F a x : 392374
RREPL. FOR:
REPL. BY:
Aufhängung
(Suspension) 31105769
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