Multiquip C30HDNI - Manual (Page 45)

MAYCO C-30HDNI (PRECISION) PUMP — OPERATION AND PARTS MANUAL — REV. #7 (04/03/12) — PAGE 45
C-30HDNI (PRECISION) PUMP — MAINTENANCE (PUMP)
Roller Chain Application
A properly selected, installed and maintained drive chain
(Figure 28) 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 29. Shaft and Drive Sprocket Alignment
The chain should be installed so the slack span is properly
tensioned. To check chain tension (Figure 30), 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 30. 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.
Figure 28. Drive Chain
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.
Recommendations and comments on how to get the most from
your roller chain drive are given in this section. The drive chain
used in the MAYCO C-30HDNI pump is manufactured by the
"DIAMOND CHAIN COMPANY
TM "
Installation and Drive Alignment
Chain and sprockets (Figure 29) 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.