A25317-A-1119
Owner's Manual for Thern 5FT20 and 5FT25 Captain Series Stationary Davit Cranes
page 9
2.3
Attaching the Load
Do not wrap the wire rope around the load. This damages the wire rope and
could cause the load to escape. Use a sling or other approved lifting device.
2.3.1
CLEAR OBJECTS from the path of the load so you can move it freely
and observe it at all times during the operation.
2.3.2
MAKE SURE THE WIRE ROPE is not twisted. A twisted wire rope
could cause the load to spin when it is raised off the ground.
2.3.3
ATTACH THE LOAD using a nylon sling, or other approved lifting
device. Follow the recommendations of the sling manufacturer.
a
SEAT THE SLING in the saddle of the hook with the hook latch
completely closed. See Figure 4.
b
CENTER THE LOAD on the hook so it will remain balanced and not tip
or rotate to one side.
2.4
Moving the Load
Do not make adjustments to the ratchet jack while the crane is loaded. To do
so may require the use of excessive force which could cause damage or injury.
2.4.1
MOVE THE LOAD slowly and smoothly, only a small distance at first.
Make sure the load is balanced and securely attached before continuing.
2.4.2
OPERATE THE WINCH to raise or lower the load. Refer to the
instructions in the Winch Owner’s Manual
.
2.4.3
OBSERVE THE WIRE ROPE as it winds onto the drum. If it becomes
loose, uneven, or overlapped, stop the operation and rewind the wire rope
before continuing.
Continued operation with overlapped or uneven
wire rope can damage the wire rope and shorten its life.
2.4.4
OPERATE THE RATCHET JACK if necessary, to adjust the angle of the
boom to keep the sheave centered over the load.
2.4.5
ROTATE THE BOOM to move the load side-to-side.
a
ROTATE THE BOOM slowly and smoothly to avoid swinging the load or
causing shock loads.
Do not jam the boom against other objects.
b
USE THE HANDLE to rotate the boom.
Do not push or pull the load or
the wire rope to rotate the boom.
Figure 4 – Attaching Load
Important!
• Obey a stop signal from anyone.
• Maintain tension on the wire
rope to keep it tightly and
evenly wound on the drum.
• If the crane and load are not
visible during the entire
operation, get help from
another person.
• Appoint a supervisor if
more than one person is
involved in the operation.
This will reduce confusion
and increase safety.
• When lifting a load, use a tag
line to keep the load from
swinging or twisting, while
keeping yourself away from the
load.
