Page 65 - FoodFocusThailand No.211 OCTOBER 2023

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which may increase the risk of valve damage. For inflammable area, high-temperature area, or area with machinery
control of flow rate, a rotary valve, such as ball valve in operation. In some cases, actuators may be used for oversized
or globe valve, may be more feasible. In addition, valves that are difficult to open and close or require frequent
environmental factors in operation areas should also opening and closing. Furthermore, actuators can also help
be considered. To illustrate, the chosen valve must be minimize human errors.
capable of resisting the pressure and temperature of Flow rate controllers can directly increase the effectiveness
the flow, which also determines the valve’s thickness of the manufacturing process and control of variables that require
and the suitability of the actuator’s design. Another adjustment. Hence, they are jointly used with automation to
factor is fluid types, such as supercritical fluid, gas, control production processes, reduce waste, and lower energy
wet gas, wet steam, vegetable oil, acid, or fluid consumption in factories. In addition, they can also control fluid
containing chemical substances or solid particles in flow’s direction and prevent leakage into gauges, thus minimizing
pipeline. These variables may cause decay in valves pressure gauge damage from high-pressure surges that can
and other anti-leak components. occur during a brief period of time.
Flow meters and controllers are essential equipment for
Common Problems of Industrial Valves measurement, check, and control of manufacturing processes
Daily production capacity needs to be accounted for in the food and beverage industry. Careful selection of adequate
to calculate the ideal flow rate, flow pattern, and flow flow meters and controllers to match specific functional purposes
resistance of a valve, all of which will subsequently is important as it can contribute to accurate measurement and
affect the choice of pumps for pumping and dispensing reliable data. Consequently, the effectiveness of the production
processes. Common problems found in valves and process will be enhanced along with the quality of products.
pipeline networks are as follows:
1) Water hammer issues may arise when the
opening or closing of a valve takes place in a sudden
manner or when a pump suddenly stops working. The
fluid’s kinetic energy will be converted into static head More Information Service Info C011
and crashing force, which will make an impact on the
valve or other parts of the pump. This phenomenon,
known as water hammer, can be prevented by
installing a check valve or other accessory. Alternatively,
opening or closing the valve more slowly can also
alleviate the problem.
2) Cavitation can occur when a fluid traverses
through a flow control valve that is not fully opened,
thus reducing static head. The fluid with reduced
pressure will vaporize, creating small vapor bubbles
in the process. Cavitation commonly occurs in steam
condensate pipework where high temperature causes
water to vaporize easily. When the fluid moves away
from the valve, the vapor will collapse and emit shock
waves that can damage the equipment. This issue
can be solved by increasing the size of pipes behind
the valve to prevent the collapse of vapor.

Benefits of Flow Control Devices
There are many types of flow controllers, such as
actuators and valves, which can work compatibly with
one another as the main controlling devices of solid
and fluid flow, such as industrial gas and liquid. They
can be categorized according to control system types
or fuel types, such as pneumatic system, hydraulic
system, electrical system, mechanical system, thermal
system, hybrid system, and manual system. These
actuators are especially useful for a case where a
valve needs to be installed in a high-risk area that is
too dangerous for a user to personally access to open
or close a valve. These areas include, for example,

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