Page 70 - Improving Machinery Reliability

42 Improving Machinery Reliability

Figure 1-27. Machinery vibration
spectrum analysis data.

5. Tabulation of minimum number of parts to be kept on hand by storehouse or
local vendor.
6. Performance curve, if applicable.
7. Mechanical seal and seal-gland drawings, if applicable.
8. Design-change data. A typical design-change form is shown in Figure 1-28. It is
used to document one of the many minor modifications which will inevitably be
made after the machinery reaches the plant. This example shows a change
which had to be implemented on oil-mist-lubricated motor bearings. After mod-
ifying the upper bearing retainer to provide oil mist flow through the bearing
instead of past the bearing, the design-change form is placed in the file folder
and a notation made on the front of the cover to let the user know how many
design-change forms he should find inside.
9. Computer input forms. These forms should be given to the equipment vendor as
part of the specification package for pumps, motors, and small steam turbines.
Providing basic equipment data should be part of the vendor's contractual
requirements. Some elements of a typical computer input form for pumps are
highlighted in Figure 1-29. In addition to information given in the API data
sheets, the equipment vendor must provide such important maintenance infor-
mation as impeller and bushing clearances, manufacturing tolerances, and as-
built internal dimensions. The computer input forms can serve as the nucleus of
a computerized failure-report system for a given plant. As a minimum, properly