The Design chain pull or P d is calculated using the following formula:

          P d = P x F s  x  F p   x  F n
where P = Total chain pull calculated from the formulas in the conveyor layout section.

F s = Speed factor from Table 10 or Table 11.
F p = Composite service factor = the product of the applicable service factors (f p)
f p = Service factors;  values of the various applicable service factors are listed in Table 9.  Before Table 9 can be used effectively an understanding of the following definitions is necessary.
UNIFORM OR STEADY LOAD - Steady loading with only minor load fluctuations.  See Table 8.
MODERATE SHOCK LOAD - Relatively smooth load fluctuations of small magnitude.  See Table 8.
HEAVY SHOCK LOAD - Rapid load fluctuations of large magnitude.  See Table 8.
FREQUENT AND INFREQUENT are broad terms.  They mean different rates of peak load or shock occurrence for different application.

The high speed drive (several hundred or a thousand RPM) expected to last several years or more would have "Frequent" shock if it occurred only a few times a day, say fifty to a hundred times.  On the other hand, if shock loading was not expected to occur at any given frequency but might happen occasionally such as once a month or once in six months due to accidental happenings, then the term "Infrequent" would apply.
The slower speed drive used on heavy equipment with an expected chain life of two or three seasons of operation would place a different meaning on the terms "Frequent and Infrequent".  Several cycles such as fifty or less would likely be termed "Infrequent".  Whereas two or three hundred cycles per day would be termed "Frequent".
In between conditions should be evaluated for their positions in the frequency pattern.

F n = Multiple strand factor = 1.2         (Where n is 2 or greater)                                n