Series 98 operation & maintenance – Bray 98 Series User Manual
Page 33

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.
S98 O & M : 33
Series 98 Operation & Maintenance
16.2 Installing SR Jackscrew Override
1. Disconnect the air pressure and the electrical power from
actuator and ensure the actuator is at its fail safe position.
2. Remove the end cover plate on the Spring module. Retain /
replace the cover O-ring.
3. Firmly tighten the mounting studs, supplied in the kit, into
the spring module end plate. Use a drop of thread lock
compound to retain the studs in the end plate threads.
4. Back off the jackscrew fully in the assembly and mount the
jackscrew assembly on the spring module end plate thrust
base.
5. Locate the Jackscrew assembly flange into the studs and
fasten with the supplied nuts and lock washers.
6. Install a suitable 3 position manual valve to the pneumatic
cylinder’s rod end port (Refer to Figure D).
16.2.1 Operating SR Jackscrew Override
1. To test / operate the override, shut off the main air supply
and turn the 3 position valve on the cylinder port to vent the
cylinder port to atmosphere. The actuator should move to its
fail safe position.
2. Turn the hand wheel on the jackscrew to advance the screw
into the spring module (see direction markers on the hand
wheel).
3. Resistance will be felt when the thrust head of the jackscrew
touches the end of the spring rod.
4. Turning the hand wheel further will compress the spring
and simultaneously turn the actuator.
NOTICE
The spring constantly loads on the jackscrew and returns the
actuator to fail safe state when the jackscrew is retracted.
Bring the actuator to fail safe position and turn the 3 position
valve on cylinder port to connect to air supply to restore auto
operation mode.
CAUTION
Never disassemble the Jackscrew assembly with the spring
load on the screw. Severe injuries/damage can result due to
non-compliance.
Retract the jackscrew completely to free the load, before
attempting any maintenance on the assembly.
Direct Drive Jackscrew -
SR