Double girder cranes are rugged in construction and
find their use in a wide range of hoisting capacities and applications. The
promoters of Aditya Cranes have experience of designing cranes up to 500 MT
Double girder EOT crane find their application in power plant, workshop
duty, transformer industry, cable industry, process plants, steel plants,
coal fields, cement plants, engineering industry to just name a few.
Heavy duty barrel winch type of double girder cranes are designed and
manufactured to customers precise needs.
Special Features of Barrel Winch Cranes :
- Capacity up to 250 MT
- Barrel Winch construction with True Vertical Lift
- Robust construction suitable for heavy duty application
- Alloy Steel, hardened, precision cut gears
- Foot mounted type fabricated gearbox casing horizontally split at
centre line for ease of maintenance for hoist
- Foot mounted hydraulic thrustor brakes for hoist
- Lift and speeds to suit your specific application
- Ample space on trolley for ease of maintenance
- L Type housing for Long travel wheels
- Full length (along the crane span) platform on the Long travel drive
- All motors are TEFC with class F insulation
- VVVF drives are available as an option
- Option for Pendent, Radio Remote and Cabin Operation
In case of double girder crane, the trolley housing hoisting and cross
traversing machinery move on the top of two bridge girders. The bridge
girders are of box construction made from rolled plates. However for smaller
capacities and spans, the bridge girders are also made from standard rolled
For standard workshop duty crane the hoisting unit is comprised of compact
wire rope hoist unit. While in case of heavy duty or higher capacity cranes,
the hoisting unit is made from fabricated and machined rope drum housing
left hand and right hand grooves to achieve true vertical lift. The rope
drum is connected to total enclosed helical gearbox through flexible drum
coupling. The gearbox is driven by electric motor either sq. cage induction
type or slip ring type. Fail safe hydraulically operated thrustor brake or
DC brake is provided on input shaft of gearbox to prevent accidental
lowering of load in the event of power failure.
For special steel mill ladle handling application, the wire rope
arrangement can be supplied with four rope independent suspension to prevent
falling of load in case of failure of one wire rope. The hoisting gearbox
can be supplied with integral planetary arrangement and two hoisting motors
for achieve hoisting motion at 50% of full speed in case of failure of one
hoisting motor. Planetary gearbox can also be supplied for operating 4 rope
grab bucket to achieve hoisting as well as grab opening/ closing operations.
Special features for hoisting arrangement include motorised hook rotation,
two hook blocks suspended from hoist drum supporting lifting beam, special
anti sway rope arrangement for rotating lifting beams, magnets suspended
from hook block/ lifting beam, tong suspended from rope system, grab bucket
suspended from wire rope system or hook type grab, hot metal handling crane
with motorised hook rotation, fixed mast crane to prevent load sway during
acceleration and deceleration.
In addition to Main Hoist (MH) an Auxiliary Hoist (AH) can also be provided
on the same trolley. On customers request, two or three trolleys can
be operated on the same pair of bridge girders for special application with
a facility for load summation.
The cross travel machinery comprises of motor gearbox and brake unit
coupled to wheel assemblies with live axles. The spherical roller bearings
housed in L type of bearing housing are provided for heavy duty application.
The bridge girders are made of plate box construction of ample strength and
rigidity. Full depth vertical diaphragms are provided inside the box for
stability. Short diaphragms are provided in between full depth diaphragms to
support the rail section that support the trolley. Horizontal diaphragms are
provided as needed to prevent buckling of web plates.
For special applications wide box girder design is provided as per customers
requirement. In this case the electrical panels are housed inside the box
girder to protect the electrical and electronic components from metallic
dust as well as heat. As an alternative to wide box girder design, a
completely enclosed electrical house supported on crane platform can be
Full length walkway platforms are provided along the LT drive side girders
for heavy and extra heavy duty cranes. Platform/ Walkways are provided on
all other cranes as per customers specifications.
Power is supplied to trolley through flexible festoon cable system. For
lower capacity and light duty cranes, compact festoon cable system or drag
chain system is used for trolley power supply. For higher capacity/ heavy
duty cranes beam rider trolleys moving on heavy duty I beams supply power to
machinery installed on the trolley.
The girders are supported at ends by rigid end carriages that house long
travel wheels. The arrangement of end carriage is decided by application as
well as number of long travel wheels that support the load. Crane capacity,
runway rail size, duty classification of crane, LT speed are some of the
factors that affect the sizing of LT wheels.
Depending on design requirement cranes with 4, 8, 12, 16 and longer travel
wheels are provided for crane LT drive. The drive unit comprises of motor,
gearbox and brake unit. Hollow output shaft gearbox that is installed
directly on wheel axle is provided for light and medium duty crane. For
heavy and extra heavy duty cranes the long travel gearbox, motor unit is
mounted on a separate LT machinery platform and the gearbox is connected to
Long travel wheel through a pair of half geared coupling and floating shaft.
In case of heavy duty cranes, the hoist, CT and LT gearboxes are made from
MS fabricated steel duty stress relieved before machining. The helical gears
are machined hob cut and are housed in precision machined housings. Gears
are dipped in oil bath and are splash lubricated.
The motor speed and torque can be controlled through variable frequency
variable voltage drives commonly known as VVVF or VFD drives as per customers
requirement. Slip ring motors with resistance control is also employed as
per the buyers choice.