MULTIQUIP MAYCO Series Operation Manual page 37

A properly selected, installed and maintained drive chain
(Figure 26) is an extremely versatile means of power
transmission. It is possible, however, to greatly reduce a
chain's life and even induce failure if the chain is abused
through improper installation, operating or maintenance
procedures. In certain applications, failure can lead to
personal injury or property damage.
Figure 26. Drive Chain
Recommendations and comments on how to get the most
from your roller chain drive are given in this section.
WORKING LOADS
UTS (Ultimate Tensile Strength) is the one-time pull
required to break the chain. For single strand chain, the
load (pull) applied to the chain in service should never
exceed 1/6th of the UTS for the chain being used except
as noted below.
It is possible to exceed the allowable working loads for a
limited number of cycles, but you should contact Diamond
Chain Company before this is considered. A roller chain
should never be loaded above 50% of UTS for even one
cycle. To do so will damage the chain structure and reduce
its capacity.
The UTS or one time breaking load of multiple strand chain
is the UTS of a single strand chain times the number of
strands; i.e., two strand chain is twice as strong as single.
When allowable working loads are considered, however,
the capacity of each strand in a multiple strand chain is only
65% of the single strand rating; thus, three-strand chain
would rate not three times single but only 1.95 times. This
is because the chain load cannot be exactly distributed
across all three strands of the three-strand chain.
MAYCO C30HDGA CONCRETE PUMP • OPERATION MANUAL — REV. #1 (09/09/19) — PAGE 37
INSTALLATION AND DRIVE ALIGNMENT
Chain and sprockets (Figure 27) must be installed
correctly. Sprockets must be properly aligned and sprocket
shafts must be parallel so the drive will run in a plane
perpendicular to them. Axial alignment should be checked
with a straight edge which will extend across the finished
sides of the sprockets. They should be true-running with
minimum wobble and eccentricity. The higher the drive
speed, the more important these details become.
Figure 27. Shaft and Drive Sprocket Alignment
The chain should be installed so the slack span is properly
tensioned. To check chain tension (Figure 28), turn one
sprocket to tighten the upper span of the chain while holding
the other sprocket fixed. The lack span should have 4-6%
of span length in the mid-span movement for horizontal
drives and 2-3% for vertical drives.
Figure 28. Drive Chain Tension
A roller chain's capacity can be significantly reduced if it
is twisted or bent sideways in the direction of the pin axis.
Exercise particular care in alignment of hoist or other
applications where loads are suspended near personnel.
MAINTENANCE