Date post: | 14-Apr-2018 |
Category: |
Documents |
Upload: | akhileshkuniyil |
View: | 219 times |
Download: | 0 times |
of 28
7/29/2019 Flow Control Applications-Tball
1/28
Flow Control Applications
Selection of valves and control
equipment
7/29/2019 Flow Control Applications-Tball
2/28
Flow Control Considerations
Flow range
Turndown required
Minimum allowable pressure drop
Maximum pressure differential
Maximum allowable noise level
Above or below grade application Customer interface (RTU, existing I/P)
Failure position
Always requires a positioner (HPP or EFP)
Avoid over-sizing the control valve Less number valves is always desirable and most cost
effective
7/29/2019 Flow Control Applications-Tball
3/28
Situations to avoid
Multiple valve configurations 1 valve is always best
High turndown situations require high turndown valve
Design flow vs. realistic flow
Design flow may not ever be achieved resulting in
oversized valve
Valve opening less than 10% at minimum flow condition
Constant cycling will occur than cannot be tuned out
High noise levels
Caused when high flow and high differential exist Constant bleed positioners
7/29/2019 Flow Control Applications-Tball
4/28
Valve Selection
Rotary Valves
Ball valves (T-Ball)
Segmented ball valves (Paramax)
Reciprocating Valves
Globe valves (CVET & 41005)
Top entry design facili-
tates maintenance andallows valve to be ser-
Kwik-ChangeCage providevariable flow
characteristicsand available
noise attenua-tion
Internal compo-nents are inter-changeable
Pressure ratingsfrom 150 to 1500ANSI
End ConnectionsAvailable:
RFFE
RTJ
Screwed EndWeld-End
Sizes Available from1 bore to 8 bore
7/29/2019 Flow Control Applications-Tball
5/28
T-Ball Comparison
Pros
High capacity
Minimum pressure drop (
7/29/2019 Flow Control Applications-Tball
6/28
Paramax Comparison
Pros
Cost effective
High capacity
Excellent low flow
controllability
High turndown (100:1)
Minimum pressure drop (
7/29/2019 Flow Control Applications-Tball
7/28
Globe Valve Comparison
Pros
Cost effective
Top entry design allows for
easy maintenance
Simple construction with
minimum parts
Noise attenuating trim up to
25 dBA reduction
Most widely known as a
control valve
Quick delivery
Cons
Single seated
Cannot be buried
Limited capacity
Minimum 5 psi pressure
differential
Low turndown (35:1)
Soft seat requires periodic
replacement especially when
debris is present
7/29/2019 Flow Control Applications-Tball
8/28
Valve Sizing & Selection Process
Use T0 ball
valve sizing program
with conditions givenBpeSize 2.3
Review flow &
Pressure conditions
Use Globe valve
Sizing program
GlobeSize 4.0
Below gradeNo
Yes
Dp < 5 psiNo
Yes
High flow rate
Yes
No
Next
slide
Use T1, T2 ball
Valve sizing program
With conditions givenT-Ball 3.5.1
Consult factory for
Paramax sizing
Alt Alt
Case 1 Max Cv:
Max flow &
Min Dp
Case 2 Min Cv:
Min flow &
Max Dp
Case 3 Max Noise:
Max flow &
Max Dp
7/29/2019 Flow Control Applications-Tball
9/28
Ball Valve Selection Process
Is T0 < 1% open
in Case 2
Noise too high
In Case 3
No Selection & Sizing
Complete
T0 is proper valve
Resize with T1 usingT-Ball sizing
program
Yes Yes
No
Is valve< 10 deg open
in Case 2
Noise too highIn Case 3
Change valve model
To T2 in T-Ball
Sizing program
Selection & Sizing
Complete
T1 is proper valve
Is valve
< 10 deg open
in Case 2
Noise too high
In Case 3
Selection & SizingComplete
T2 is proper valve
Globe
Valve
required
Yes Yes
NoNo
NoNo
Yes
Yes
Use diffuser or
Silencer w/ valve
7/29/2019 Flow Control Applications-Tball
10/28
Globe Valve Selection Process
Is valve
> 10% openin Case 2
Consult factory for
alternatives
No
Required
Noise levels met
In Case 3
Yes
Does valve
meet max Cv
in Case 1
Yes
Use ball valve
for application or
multiple runs
No
Selection complete
Globe valve properly
Sized and configured
No
Use1-stage or 2-stage
Noise trim
7/29/2019 Flow Control Applications-Tball
11/28
Typical Flow Control Valve
Most common flow control valve is configured as follows:
Model T0 T-Ball Full Port Ball Valve, RFFE
RPDA Series Double-Acting Actuator
EFP-2 Electro-Pneumatic Positioner
MCV-3 Manual Control Valve
FD-1 Gas Supply System
T-1F ball valve with same components 2nd most common
configuration
Schematic
7/29/2019 Flow Control Applications-Tball
12/28
Optional Equipment
Pressure control override (VRP pilot)
High pressure shutdown (Pressure sensor or Gap
controller)
Failsafe overrides (power gas loss, electrical signal loss,
electrical power loss)
7/29/2019 Flow Control Applications-Tball
13/28
Example Flow Control Application:
Customer: Panhandle Eastern Pipe Line
Location: Indianapolis, IN
Sizing: 6 T-1F
8 T-1F
Competition: Fisher EWT globe valves
Note: 3 globe valves runs required to maximum flowrate. Noise is an issue. Below grade not an
option.
7/29/2019 Flow Control Applications-Tball
14/28
Example Flow Control Application:
Single flow control valve with 8 Becker model T-1F withRPDA actuator and EFP-2 electro-pneumatic positioner if
high flow, high differential condition does not exist Dual run flow control valves with 6 Becker model T-1F with
RPDA actuator and EFP-2 electro-pneumatic positioner if allflow and pressure conditions exist
External diffuser offered to meet low noise requirement EFP is non-bleeding positioner
Less valves provides a more cost effective approach up
front
Non-bleeding positioner provides lower operating cost infuture
7/29/2019 Flow Control Applications-Tball
15/28
Flow Control Valve
InstrumentationPneumatic PositionersElectro-Pneumatic Positioners
7/29/2019 Flow Control Applications-Tball
16/28
HPP-4 Double-Acting Pneumatic Positione
Positioner used with RPDA &SYDA actuators
3-15 psig or 6-30 psig input signal Seat & Nozzle constant bleed
design
Ideal for downstream bleedapplications < 300 psig
psi signal accuracy Used on 2 42 valve sizes
All materials 100% natural gascompatible
Simple adjustment
7/29/2019 Flow Control Applications-Tball
17/28
HPP-5 Double-Acting Pneumatic Positione
Positioner used with RPDA &
SYDA actuators
3-15 psig or 6-30 psig input signal
Balanced valve design offers
near zero atmospheric bleed
Can bleed to a pressure system