 |
|||
|
|
|||
| ||||||||||
|
|  MIL-P-17639F(SH)
3.3.6.2 The shaft (pump or driver), except those driven by ac motors,
shall be provided with means to permit the ready and direct use of portable
tachometers. When this is impracticable, provision shall be made for the use
of a portable tachometer on the shaft of the driver.
3.3.6.3 Shafts shall be fitted with shaft sleeves in way of all wearing
surfaces, such as stuffing boxes, bushings, and water lubricated bearings.
O-rings shall be installed between the shaft sleeve and shaft.
3.3.6.4 Shaft flingers shall be provided adjacent to the gland for all
pumps. The flinger shall be so located that leakage which might occur between
the gland shaft sleeve and the shaft, as well as from the gland, is not allowed
to reach pump or motor ball bearings. For rigid coupled units, the coupling may
serve as the pump flinger provided the coupling is constructed of corrosion-
resistant material.
3.3.6.5 Shafts of class C-1 close-coupled pumps shall be of one-piece
construction.
3.3.6.6 Shafts of class C-2 pumps, except those driven by ac motors,
shall be provided with means to permit the ready use of portable tachometers.
3.3.7 Rotating assembly.
3.3.7.1 Rotors shall be dynamically balanced with all rotating parts
connected thereto; for common shaft assemblies, or those using rigid coupling,
this requires dynamic balance with the rotating element of the driving unit in
place. However, rotating parts may be balanced individually provided that,
when assembled, the imbalance shall not exceed the limits specified in
MIL-STD-167-1.
3.3.7.2 Where balancing is required as a maintenance procedure to maintain
proper vibration or noise performance of the pump and driver unit in service, the
pump shall be designed such that balancing may readily be performed by overhaul
activity personnel.
3.3.7.3 The pump design shall be such and calculations shall be made to
demonstrate that the maximum operating speed of the pump will not be greater
than 70 percent of the first critical speed.
3.3.7.4 Impellers, shafts, and other parts of the rotating assembly shall
not contain radially oriented setscrews, except setscrews solely used as balanc-
ing weights in the balancing ring design required by 3.3.7.5 are acceptable.
3.3.7.5 A balance ring shall be located in the coupling area between the
lower motor bearing and the pump stuffing box, allowing sufficient clearance
for packing gland adjustment. The balancing ring shall include the features
and ounce-inch capacity specified in MIL-E-917 for submarine rotating equipment
balance rings.
3.3.8 Stuffing boxes and mechanical shaft seals.
3.3.8.1 Mechanical seals. All pumps shall be provided with mechanical
shaft seals. Magnetic type seals shall not be used.
19
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals