DENT LIMITS FOR SINGLE-TAB CUP WASHERS
L-41306
Cup Washer Installation
Figure 204 (Sheet 2)
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
70-21-00
ALL ú
ú N01 Page 209
ú Feb 10/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
D. Procedure (Fig. 204)
S 422-030-N00
(1) Do these steps when you install the cup washer:
(a) Crimp tools:
NOTE: The crimp tool (that makes the dents) must have a
____ spherical shape with a radius of not less than 0.050 inch (1.270 mm).
1) Squeeze-action crimp tool
a) This tool makes dents on the external diameter of the cup washer and moves the cup into the slots of the nut or the bolt (SECTION A-A).
b) You must use this recommended crimp tool when you can.
2) Drift a) A drift tool has a ring with projections on it. b) Put the drift tool around the cup washer. c) Move the drift tool in an axial direction to make dents
in the cup washer (SECTION B-B). 3) Punch
CAUTION: DO NOT USE THE PUNCH TO MAKE DENTS IN THE CUP
_______ WASHERS THAT YOU INSTALL ON FUEL INJECTOR NUTS. IF YOU USE THE PUNCH IN THESE LOCATIONS, DAMAGE TO THE FUEL INJECTOR CAN OCCUR.
a) Hit the punch with a hammer to crimp the wall of the cup washer (VIEW B, C, D and F).
S 422-015-N00
(2) The specified number of dents:
(a) You must make dents in the cup washer in the correct number of locations. 1) See TABLE A, unless a different specification applies.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
70-21-00
ALL ú ú N01 Page 210 ú Feb 10/92
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
(b)
You can find less rounded slots on the fasteners than the number of dents in TABLE A. 1) Then crimp the cup washer in all of the available
locations.
(c)
For cup washers with one tab, crimp the cup washer (VIEW G).
(d)
For eight slot nuts with a thread dimension of 2.500-4.000 inch (64-120 mm), crimp the cup washer (View E).
S 212-027-N00
(3) Position control:
(a) Do these steps to prevent damage to the keys:
1) Use the marking pencil to make a mark on the cup washer and the adjacent surface that does not turn.
NOTE: Do not make the mark on the fastener because it
____ can turn with the cup washer.
2) When you tighten the fastener, look at the mark to make sure that the cup washer does not turn.
S 422-028-N00
(4) Permitted standards:
(a) Correctly installed cup washers have these properties:
CAUTION: DO NOT USE CUP WASHERS THAT ARE SUFFICIENTLY LOOSE TO
_______ SHAKE. IF THE WASHERS ARE LOOSE, DAMAGE TO THE ENGINE CAN OCCUR.
1) You installed a new cup washer with the instructions that we have given. 2) You made the dents in the cup washer as shown in (Fig. 204). 3) A cup washer will usually feel tight, unless a fastener applies no axial force to the diaphragm of the cup washer.
NOTE: Then you can move the cup washer through the
____ limits of the key clearance.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
70-21-00
ALL ú ú N01 Page 211 ú Jun 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
4) All the dents in the cup washer almost have the same shape and dimension.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747-400 AMM 飞机维护手册 STANDARD PRACTICES - ENGINE(20)
