184.108.40.206.1 Vertical fan-cooled motor covers. - Vertical fan-cooled motors shall be furnished with a
solid cover over the fan assembly to prevent personnel injury and to prevent foreign particles from falling
into the fan.
220.127.116.11 Aluminum end shields. - Aluminum end shields (see table VIII) shall not support the total
weight of the motor or driven auxiliary unless approved by the bureau or agency concerned. Steel inserts
shall be provided for all threaded portions and bearing housings.
3.1.18 Shafts. - A shaft extension shall be provided to suit the driven apparatus. Unless otherwise
specified in the contract or order, the shaft extension shall be in accordance with figure 1.
bearings. - Bearings shall be of the ball or sleeve type, as specified (see 6.1).
bearings. - Ball bearings shall be in accordance with FF-B-171 and shall be of the
following types, as specified (see 6.1):
(a) Type III, classes 3 and 8.
(b) Type 120.
(c) The use of other types for special application requirements shall be approved by the bureau or
seals. - A close clearance running seal shall be provided on both sides of
the bearings to prevent the leakage of grease along the shaft.
construction. - The bearing housing shall be so constructed as to permit ready
removal of the end shield preferably without the necessity of removing the bearings.
18.104.22.168.3 Removal of bearing. - The design shall be such as to permit removal of the ball bearing by
pulling on the inner race of the bearing with one of the tools contained in a "complete" Naval shipboard set
of tools specified in GGG-P-781.
22.214.171.124.4 A plate bearing the warning `WARNING DO NOT LUBRICATE" shall be permanently at-
tached to the motor.
3 . 1 . 1 9 . 3 Sleeve bearings. -
3 . 1 . 1 9 . 3 . 1 Lubrication of sleeve bearings. - Sleeve bearings shall be lubricated by means of an oil
wick or wool yarn or shall be of the self lubricated type.
126.96.36.199.2 End play (sleeve bearings only). - To insure floating of the shaft in horizontal sleeve-
bearing motors, there shall be at least 1/64 inch end play in either direction.
3.1.20 Rotor and stator core. -
188.8.131.52 Securing core to shaft. - Provisions shall be made to prevent rotation of the core on the shaft
and axial displacement of the core along the shaft. Keys knurling of the shaft or keys in conjunction with
press or shrink fits shall be provided to prevent rotation of the core around the shaft. Press or shrink fits
without keys to secure the core on the shaft to prevent axial or rotational movement of the core shall be as
approved by the bureau of agency concerned. Tack welding in conjunction with other means (press or
shrink interference fits) will be permissible to prevent axial displacement of the core along the shaft.
3 . 1 . 2 0 . 2 Securing stator core to frame. - Provisions shall be made to prevent rotation of the core in
the frame and axial displacement of the core along the frame.
3.1.21 Commutators (where used). -
184.108.40.206 General. - The commutator shall be secured rigidly to the shaft by means of a shrink or press
fit or other method satisfactory to the bureau or agency concerned which will positively secure the com-
mutator in such a manner as to prevent either rotational or axial motion of the commutator relative to its
support under operating conditions.