Yokogawa Advanced Reflux Sampler - Manual (Page 15)

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All Rights Reserved. Copyright © 2011, Yokogawa Electric Corporation. Subject to change without notice. April 2011 IM 11A00V01-01E-A
10.2.2 Installation and Commissioning
NOTE
Before starting any installation observe the “Safety information” Section 10.2.1.
The valve should always be fitted in a horizontal pipeline with the flow in the direction indicated by the arrow marked on
the body with the sensor in a vertical plane below the pipeline as shown in Fig. 1 .(SA control system). Valves should be
mounted in the pipeline in accordance with the actuator installation and Maintenance Instructions.
A suitable strainer should always be fitted upstream of the valve. Additionally on steam installations a separator should be
fitted before the valve, plus a steam trap set on applications where condensate may accumulate upstream of the valve
WARNING
The control system actuator must be securely connected to the valve via the screwed connection on the bottom of the
valve and the half union coupling on the actuator before any fluid is allowed to pass through the valve. Similarly, the
actuator should not be disconnected from the valve until the valve itself. is fully isolated
It is important that line stresses i.e. expansion or inadequate supporting of the pipe are not imposed on the valve body.
If the valve is properly sized for the duty it has to perform it will often be smaller than the pipeline. This is particularly so
where the medium passing through the valve is steam, in which case any reduction in line size should be made using
eccentric reducers. The piping on both upstream and downstream sides of the valve must be of ample size to avoid
undue pressure drop in the line and any reduction to meet the size of the valve should be made close to the valves as
shown in Fig. 1
It is advisable to protect the valve by fitting a strainer on the upstream side. By fitting the strainer on its side where the
medium is steam you will prevent the body filling with water which would reduce the screening area.
In most steam installations~ water formed by condensation due to radiation losses will be present in the upstream pipeline
and should be removed by an adequate drain point and trap, as shown in Fig. 1.
NOTE
For commissioning instructions refer to the Operation, Installation and Maintenance Instructions, covering Yokogawa
control systems.
10.3 Safety Information
10.3.1 Hazardous Liquids or Gases in the Pipeline
Consider what is in the pipeline or what may have been in the pipeline at some previous time. Consider: flammable
materials, substances hazardous to health, extremes of temperature.
10.3.2 Hazardous Environment around the Product
Consider: explosion risk areas, lack of oxygen (e.g., tanks, pits), dangerous gases, extremes of temperature, hot surfaces,
fire hazard (e.g. during welding), excessive noise, moving machinery.
10.3.3 The System
Consider the effect on the complete system of the work proposed. Will any proposed action (e.g. closing isolation valves,
electrical isolation) put any other part of the system or any personnel at risk?
DANGER
Dangers might include isolation of vents or protective devices or the rendering ineffective of controls or alarms. Ensure
isolation valves are turned on and off in a gradual way to avoid system shocks.