172-65175MA-13 (COS Pressure Reducing Valve) 16 Feb 2022
5
Correct Usage of the COS Pressure Reducing Valve
Install properly and DO NOT use this product outside the recommended
operating pressure, temperature and other specification ranges.
Improper use may result in such hazards as damage to the product or
malfunctions which may lead to serious accidents. Local regulations
may restrict the use of this product to below the conditions quoted.
CAUTION
1. The COS should be operated only within its specifications.
2. Installing an ON/OFF Valve (Solenoid Valve or Motorized Valve)
If an on-off valve, such as a motorized valve, is required to stop supply of
steam to the steam-using equipment, install it at the inlet side of the COS. If a
solenoid valve is installed at the outlet of the COS, its opening and closing will
cause heavy chattering and may lead to damage of the piston and main valve.
(When the on-off valve opens, the secondary pressure of the COS changes
from zero to the set pressure. Passing through an area of the reducing ratio of
less than 10:1, where adjustment is impossible, chattering occurs
momentarily.) To save energy, it is recommended to install the on-off valve as
near to the boiler as possible.
NOTE: To prevent water hammer, it is recommended that a slow-acting
motorized on-off valve be used. In particular, if a fast-acting on-off solenoid
valve is used for frequent temperature control, the potential water hammer
effect can damage the steam-using equipment and the COS.
3. Installing a Control Valve and Safety Valve
A control valve installed between the COS and the steam-using equipment
(downstream of the COS) for controling equipment temperature may raise the
pressure between the COS and the control valve when the control valve is
closed, depending on the spatial relationship. A safety valve should be
installed downstream of the control valve.
Note: When installing a safety valve to protect the steam-using equipment, be
sure to install it on the steam-using equipment or directly before the inlet of the
steam-using equipment. If the safety valve is installed on the outlet side of the
COS between the COS and a control valve, an eventual pressure rise could
activate the safety valve.
COS
Inlet side
Motorized
Valve
COS
Outlet side
Solenoid
Valve
Steam-using
Equipment
Steam-using
Equipment
COS
Control
Valve
Safety
Valve
Steam-using
Equipment
Steam-using
Equipment
COS
Control
Valve
Safety
Valve
