Butterfly valve provide shuting off for tight seal, but can butterfly valve also be used as control valve ? Some people say it's fine to use, and some people believe that is just a way of cheaping out on the process. No way a butterfly valve can provide controlling purpose as per needed. who is right ?
Our engineer advise that buttefly valve can be used in control application, but it also depend on detail requirement of using process conditions .
As we know butterfly valve is an economical choice. this kind valve is a great (and less expensive) alternative to globe valve , ball valve and other control valves in applications where 1-2% accuracy is acceptable. Process conditions will dictate whether a resilient seated or high performance butterfly valve should be selected. The resilient seated (EPDM, NBR, Viton, Etc ) butterfly valve is the most economical choice, if pressures and temperatures are not extreme, this type of valve should work just fine. If pressure and temperature exceed the limits of a resilient seat, need to choose high performance butterfly valve.
The limitation of butterfly valve be used as control valve is butterfly valve donot have a linear flow characteristics, but other control valves have. Butterfly valve’s design donot have linear flow characteristics (because the shape of the disc and its relationship to the pipe), it makes more difficult to control.
Consider that add instruments and positioners to the valve to help control the valve more accurately, in addition, it is an ideal condition for proper control to ensure operating conditions. It is always necessary to consider high temperature and high speed, which is not butterfly valve can provide.
Although butterfly valves are not the right choice for processes requiring precise control, like making paint and food flavors, but do not exclude butterfly valve out of our concideration. It still is good choise in the control valve category. Engineer suggests that look to butterfly valves first in control applications. because that could mean the difference between $100 and $1,000, comparing butterfly control valve and other control valve.
ZFV ( Zhejiang zhengfeng valve co., ltd ) is a professional factory manufacturing butterfly valve, withflange end, wafer end, LUG end and butt weld end type , etc. Available manufacturing standard include API, DIN, JIS. GOST, EN, ISO, GB and so on . also produce special standard valve by customer's order.
Zhejiang zhengfeng valve co., ltd