Bell System Practices KS-19992 Operation And Maintenance Manual

BELL SYSTEM PRACTICES
AT&TCo Standard
SECTION 770-225-310
Issue 1, February 1972
1.
2.
3.
4.
5.
6.
.
7.
1.
BLAST VALVE
KS-19992 AND KS-20134
OPERATION AND MAINTENANCE
CONTENTS PAGE
GENERAL . . . . . . . . . . .
LIST OF TOOLS, MATERIALS, AND TEST
APPARATUS. . . . . . . . . .
GENERAL DESCRIPTION AND PRINCIPLE OF
OPERATION . . . . . . . . . .
OPERATION' . . . . . . . . . .
A. Normal Operation . . . . . . .
B. Manual Operation . . . . . . .
ROUTINE CHECKS . . . . . . . .
ROUTINE MAINTENANCE . . . . .
A. General . . . . . . . . . .
B. Lubrication . . . . . . . . .
C. Replacement Procedures . , . .
D. Adjustment Procedures . . . . .
TROUBLES . . . . . . . . . . .
GENERAL
1
3
3
8
8
8
13
17
17
17
17
21
23
1.01
The KS-20134 ventilation closure blast valve
and the KS-19992 turbine exhaust blast valve
are butterfly type valves which are used in hardened
underground telephone buildings. The valves mount
between standard 24-inch pipe flanges and are
designed to close within 50 to 100 milliseconds in
response to an electrical signal or as a result of
an air blast (see Fig. 1).
1.02
This issue does affect the Equipment Test
List.
Winning: The blast valve is a potentially
dangerous mechanism. It operates so
rapidly that evasive action is impossible.
The valve may trip at any thne from any
position horn full closed to full open. All
personnel working on or near the valve
must be warned regdng the hazard.
1.03
The blast valve is designed to close in 1/20
of a second as a result of an air blast or
through interruption of a 24-volt de electrical control
circuit. The blast valve consists of the butterfly
valve blade, mounted in a valve housing, with an
enclosed spring driven actuator, a tripping mechanism,
a resetting means, a shock absorber, and electrical
components. The resetting mechanism may be
driven by an electric motor or manual operation.
Reset drive motors of different list numbers are
mechanically interchangeable.
1.04
The KS-19992 turbine exhaust blast valve is
designed for installation in the turbine exhaust
ducting of hardened underground sites to protect
the turbine in the event of an external nuclear
explosions. The KS-19992 blast valve is available
with the mechanically interchangeable reset motors
for the voltages in Table A.
1.05
The KS-20134 ventilation closure bIast valves
are designed for installation in the ventilation
inlet and exhaust system ducts in hardened
underground sites to protect equipment and personnel
from blast waves in the event of an external nuclear
explosion.
The KS-20134 blast valves are installed
with 1, 2, 3, or 4 valves mounted in a single plane
with their shafts connected in line and using only
one actuator assembly. The blade/actuator relationship
and blade joining sequence are shown in Table B.
The reset motor voltages are also listed in Table
B.
@ American Telephone and Telegraph Company, 1972
Printed in U.S.A.
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