DT
3.- ACTUATORS
3.1.- Pneumatic
Valves are usually supplied with a double acting pneumatic actuator although, upon request,
we can supply single-acting actuators. In either case the feed pressure can vary between 3,5
and 10 Kg/cm2.However, the size of the actuator for each valve has been designed for a feed
pressure of 6 Kg/cm2.
It is essential for a good maintenance of the cylinder that air should be well dried, filtered and
lubricated.
It is recommended to actuate the cylinder 3-4 times before the start up, once it is installed in the
pipeline.
4.- MAINTENANCE
The valve must not undergo any modifications without a previous agreement with ORBINOX.
ORBINOX shall not be liable for any damages that may arise due to the use of non original parts or
components
To avoid personal injury or damage to property from the release of process fluid:
-Those in charge of handling and maintenance of the valve must be qualified and trained in
valve operations.
-Use appropriate personal protection equipment (gloves, safety shoes, etc).
-Shut off all operating lines to the valve and place a warning sign.
-Isolate the valve completely from the process.
-Release process pressure.
-Drain the process fluid from the valve.
-According to EN 13463-1 (15), during installation and maintenance operations, use hand
tools (non electric) with Working Allowance.
In an ATEX zone, there may be electrostatic charges in the internal parts of the valve. These
electrostatic charges, caused by the evacuation of the fluid, may entail a risk of explosion. It is the
responsibility of the user to take extreme precautions to minimize this risk.
Safety in an ATEX zone:
- The maintenance personnel must be made fully aware of the risks of explosion, and it is
advisable that they receive specific training regarding ATEX.
- Should the fluid transported create an internal explosive atmosphere, the user must check
periodically the correct water-tightness of the installation
- Clean the valve periodically to prevent dust accumulation.
- Assembly at the end of the line is not allowed.
- Avoid repainting the products supplied.
The only maintenance required is to change the gland packing (4) and the seal (9).
The life of these elements will depend on the working conditions of the valve such as: pressure,
temperature, abrasion, chemical action, number of operations, etc.
4.1. - Replacement of the gland packing (4):
1) Depressurise the circuit and place the valve in close position.
2) Remove the gate guards (for automatically actuated valves only).
3) Release the stems (10) from the gate (3). (Photo 1)
4) Loosen the screws of the yoke (6) and remove it (without loosing the actuator).
5) Loosen the nuts of the gland followers (5) and remove them. (Photo 2)
6) Remove the old packing rings (4) and clean the stuffing boxes.