Bray 92_93 Series FLO - Manual (Page 4)

2 All information herein is proprietary and confidential and may not be copied or reproduced without the expressed written consent of BRAY INTERNATIONAL, Inc.
The technical data herein is for general information only. Product suitability should be based solely upon customer’s detailed knowledge and experience with their application.
Series 92-93 Pneumatic Actuator
Operations and Maintenance Instructions
Correct and safe operation of this actuator is depen-
dent upon proper transport, storage and installation
in addition to proper operation and maintenance.
Description of Operation
The Flow-Tek Series 92/93 Pneumatic Actuators
feature a double piston, rack and pinion mechanism
designed to automate quarter-turn valves. In the
Series 92 Double-Acting Actuator, pressure intro-
duced through Port A (the left port when facing
the ports) forces the pistons away from each other
and causes the pinion to rotate in a counterclock-
wise direction. Pressure introduced through Port
B (the right port when facing the ports) is directed
through an internal passage to the opposite side
of the pistons, which forces the pistons together
and rotates the pinion in a clockwise direction.
Normally, the clockwise rotation (pistons moving
together) closes the attached valve, and the coun-
terclockwise rotation (pistons moving apart) opens
the attached valve.
In the Series 93 Spring-Return Actuators, spring car-
tridges have been added to push the pistons together
by spring force in the event the compressed air pres-
sure is lost. This spring force normally closes the
attached valve. However, in the event that the valve
is required to open under spring force, refer to the fail
open portion of the Installation section below.
Operating Medium
NOTICE
The recommended operating medium is clean, dry
industrial compressed air, 40 - 140 psig (3 - 10
bar.) An air line lubricator is suggested for fast
cycling applications, i.e. more than 10 cycles per
minute. Other media such as hydraulic oil, water,
or certain other inert gases may also be used in
some instances, but the factory should be consulted
for specific applications.
Operating Temperature
NOTICE
The recommended operating temperature range
is -15°F to 200°F (-25°C to 95°C). Below 32°F
(0°C) care must be taken to prevent condensed
moisture from freezing in the air supply lines.
Consider the use of an air dryer if the device is
installed in a cold location. The air dryer must
be capable of lowering the dew point of the air to
a temperature 36°F (20 °C) lower than that of the
surrounding environment. The air dryer must be
properly maintained and kept in operation.
Installation
Flow-Tek Series 92/93 Actuators are designed
to Flow-Tek Valves through a series of heavy
duty brackets and couplers. Before the actuator
is mounted on a valve, it is a good practice to
lubricate the output bore of the actuator with thick
grease. The grease will make it easier to remove
the actuator from the mounting coupler, even after
years of service.
Normally, the actuator is mounted with its long side
parallel to the pipeline. A double acting actuator will
normally rotate the valve stem clockwise to close,
and counterclockwise to open. Spring return actua-
tors will normally rotate the valve stem clockwise to
close with the spring stroke, and counterclockwise
to open with the air stroke. The normal operation
of the spring cartridges is therefore fail closed.
Direction of operation may be changed to fail open
by any one of several different methods. Refer to
the Assembly Instructions and Exploded View in
Figure 3 on page 12 for more details.