
Class A
(STANDBY OR INFREQUENT SERVICE)
This service class covers cranes that may be used in installations such as
powerhouses, public utilities, turbine rooms, motor rooms and transformer
stations where precise handling of equipment at slow speeds with long, idle
periods between lifts are required. Capacity loads may be handled for
initial installation of equipment and for infrequent maintenance.

Class B
(LIGHT SERVICE)
This service covers cranes, which may be used in repair shops, light
assembly operations, service buildings, light warehousing, etc., where
service requirements are light and the speed is slow. Loads may vary from no
load to occasional full rated loads with two to five lifts per hour,
averaging ten feet per lift.

Class C
(MODERATE SERVICE)
This service covers cranes that may be used in machine shops or paper mill
machine rooms, etc., where service requirements are moderate. In this type
of service the crane will handle loads that average 50 percent of the rated
capacity with 5 to 10 lifts per hour, averaging 15 feet, not over 50 percent
of the lift at rated capacity.

Class D
(HEAVY SERVICE)
This service covers cranes which may be used in heavy machine shops,
foundries, fabricating plants, steel warehouses, container yards, lumber
mills, etc., and standard duty bucket and magnet operations where heavy duty
production is required. In this type of service, loads approaching 50
percent of the rated capacity will be handled constantly during the working
period. High speeds are desirable for this type of service with 10 to 20
lifts per hour averaging 15 feet, not over 65 percent of the lifts at rated
capacity.

Class E
(SEVERE SERVICE)
This type of
service requires a crane capable of handling loads approaching rated
capacity throughout its life. Applications may include magnet, bucket,
magnet/bucket combination cranes for scrap yards, cement mills, lumber
mills, fertilizer plants, container handling, etc., with twenty or more
lifts per hour at or near the rated capacity.

Class F
(CONTINUOUS SEVERE
SERVICE)
This
type of service requires a crane capable of handling loads approaching rated
capacity continuously under severe service conditions throughout its life.
Applications may include custom designed specialty cranes essential to
performing the critical work tasks affecting the total production facility.
These cranes must provide the highest reliability with special attention to
ease of maintenance features.
