Thern FVC-1000, Owner'S Manual, Page: 7 / 24

Owner's Manual for Thern Model FVC-1000 Winches page 7
A8018B-1210
2.1
General Theory of Operation
2.1.1
THE FORCE REQUIRED to seal the fi re vent must not exceed the load
rating of the winch.
2.1.2
THIS EQUIPMENT CAN develop forces that will exceed the load rating.
Inspect the equipment regularly for damage according to the instructions
contained in this manual.
2.1.3
PERFORMANCE RATINGS of the equipment are affected by the amount of
wire rope wound on the drum and the way in which it is wound.
a
DRUM CAPACITY depends on how tightly and evenly the wire rope is
wound on the drum. Actual drum capacities are usually 25-30% less than
values shown in performance tables, due to loose winding and overlapping.
b
HANDLE FORCE REQUIRED the load increases with each additional layer
of wire rope wound onto the drum. Line speed also increases with each ad-
ditional layer of wire rope wound onto the drum.
c
LOAD RATING represents the maximum pull that can be placed on new
equipment. Load ratings are assigned values for specifi c amounts of load
travel or wire rope accumulation. The load rating decreases as layers of wire
rope accumulate on the drum.
2.1.4
DUTY RATINGS refer to the type of use the equipment is subject to. Con-
sider the following when determining duty rating.
a
ENVIRONMENT: harsh environments include hot, cold, dirty, wet, corro-
sive, or explosive surroundings.
Protect the equipment from harsh envi-
ronments when possible.
b
MAINTENANCE: poor maintenance, meaning poor cleaning, lubrication,
or inspection, leads to poor operation and possible damage of the equipment.
Minimize poor maintenance by carefully following the instructions con-
tained in this manual.
c
LOADING: severe loading includes shock loading and moving loads that
exceed the load rating of the equipment.
Avoid shock loads, and do not
exceed the load rating of the equipment.
d
FREQUENCY OF OPERATION: frequent operation increases wear and short-
ens the life span of gears, bearings, and other components.
Increase mainte-
nance of the equipment if used frequently.
CONTACT THE FACTORY FOR MORE INFORMATION.
Important!
• Limit nonuniform winding by
keeping tension on the wire rope
and by maintaining the proper
fl eet angle.
• It is your responsibility to detect
and account for different fac-
tors affecting the condition and
performance of the equipment.