Warren Globe Valves
Globe valves have earned their distinction as the preferred control valve style.
The flow path through a globe valve spreads a pressure drop through the entire
device, while other valve styles tend to concentrate the pressure drop at the
vena contracta. The vena contracta is the place in the final control element
where flowing velocity is at its maximum, and pressure is at its minimum. It is
the place where phenomena such as "flashing",
"choking"
and "cavitation"
originate. Because it slows pressure drop and recovery rates within its body,
the globe valve is more resistant than ball, plug and butterfly valves to those
counter-productive, sometimes destructive events. This inherent stabilizing
characteristic of the globe valve enhances its ability to control a fluid
stream. Additionally, ball valves have inherently higher dB levels of audible
noise compared to globe valves, contributing to potential OSHA violations,
regardless of the now common characterized trims.
Valve Selection If a formal
valve specification is not available, obtaining most of the following
information can get the discussion started. You can also use this email
worksheet to have one of our technical support
specialists guide you through the selection process. The same criteria is also
beneficial with a formal valve specification but the selection process becomes
simpler.
• Identify if valve is a
2-way valve for flow, pressure or temperature control or a 3-way mixing, bypass
or diverting application
• Type of operator – Pneumatic or Electric
• Control Signal (type and value) and any required accessories
• Modulating Service or ON/OFF Service
• Valve size, connections & materials of construction if important
• Flowing Medium (water, steam, air, etc.)
• Flow Rate required (gpm, lb./hr., scfh, etc.)
• Pressure at the valve inlet (psig - Normal & Maximum)
• Pressure drop available fully open (psid)
• Temperature at the valve inlet (deg. F - Normal & Maximum)
