FF-906 Positioner Transducer Block - Fieldbus Foundation

Positioner type 3730-5
SSmart t VValve l Positioner P iti with ith
diagnostic functions
Presented By: Mr. Gourishankar Saharan
Product management
Jens Bargon / V42

Product overview
PProcess VValves l
� Control Valves
� Positioner and Accessories

Control Valves & FF Smart Positioners
� Control Valves are the “work horses”
in every process plant
� They are subject to wear and tear
and therefore an important target
for asset management and predictive
maintenance procedures
Smart positioners with integrated diagnostic
functions and FOUNDATIONTM Fieldbus technology
ddeliver li optimal ti l solution
l ti

Control Valves & FF Smart Positioners
Typical valve failures
� Eroded seat and plug → internal leakage
� Erosion of valve body → finally external leakage
� Leaking stuffing box → external leakage
�� Increased / decreased friction → higher / lower hysteresis
� Closing (Zero) point shifting → deposits on sealing edge
� Change in opening / closing breakaway torque (e.g. ball valves)
� Poor control performance → External leakages in the pneumatic supply

What is diagnosis?
�� Usually the term „diagnostic diagnostic“ is used in the medicine and means
interpretation of symptoms with the target to get information about the
actual status or reasons of a malfunction.
� 1 step: condition monitoring → measuring different process parameters
� Deliver symptoms of expected or existing malfunctions
� 2 step: diagnosis → interpretation of the process parameters
� By experienced service personal
� Better: via software, based on experienced algorithms
� 3 step: maintenance requirements / measures → constructive steps
� Service-> Keep the working condition
�� RRecondition-> diti RRestore t th the working ki condition
diti

Where do the diagnostic messages appear?
Type 3730-5

Condensed state acc. to NAMUR recommendation NE 107
� Classified status messages (forms & colors):
� good
� maintenance required / demanded
�� failure
� function check
� out of specification
� Classification by End User
�� Highest rated message determines
the condensed state
Internal device failure
GOOD_MAINT_REQ
Working at full capacity
Perhaps not enough air
N No message/diagnostic /di ti active ti
Shifting working range close
Perhaps bias reduced TEST

Condensed state acc. to NAMUR recommendation NE 107

Condensed state acc. to NAMUR recommendation NE 107
� So far the DI function block of the positioner type 3730-5 is used to
read in the condensed state into the host
Condensed state configuration
� Examples: M/s. Bayer, China.
Plant is in Caojing and has nearly 11.000 FF devices with around 3000 of positioner
type yp 3730-5 running g well in the pplant also using g the ppositioner diagnosis. g

Condensed state acc. to NAMUR recommendation NE 107
� In future devices and systems are working according to Specification FF 912 “Field
Diagnostic Profile” (required for devices tested with ITK6.0)
Source: FF-912 chapter 1.3

Monitoring functions during the running process
� General requirements
� Diagnostics should be realized without any additional sensor systems
� The valve is in controlled operation and the process may not be to interrupted!
� Histograms allow to evaluate the valve travel [x], the set point deviation [e]
and the valve cycle counter as an automatic function without any setup in the
background
� The valve signature function allows …
� to detect possible changes in friction
� to detect poss possible b e cchanges a ges in tthe e supp supply y ppressure essu e oor maybe aybe leakages ea ages in tthe e ppneumatic eu at c supp supply y
� The Final position trend monitoring function allows to detect a fluctuating or creeping
zero point due to seat & plug wear or material between seat and plug
�� Dynamic Stress factor to monitor the stuffing box
� Partial Stroke Test for on/off applications
� Leakage sensor to detect inner leakages between seat & plug

Cycle counter details
� The operator needs to differentiate the
stuffing box! The corresponding values are
based on experiences in the SAMSON
development department!
� Self-adjusting
� Adjustable packing
�� Bellows seal
� Other � adjustable threshold
� Dynamic y a c st stress ess factor acto [%]
� The rate of wear of the selected stuffing box
will be calculated
� New: 0%
� Statistical defect 100%
� Above 90% a message will be
generated
� Long-term o g e histogram s og a

Cycle counter in practice
Parex Process
� The pump around valve sees every two minutes new process conditions, when the
Rotary Valve has been switched and two new column beds are connected to each
other.
� The process requires a fast and precise response of the control valve controlling the
flow to the adsorption chambers, leading to a high number of cycles.
Source: UOP LLC 25 East Algonquin Road, Des Plaines, IL 60017-5017

Cycle counter in practice
Parex Process
� Valve requirements
� Optimized pneumatic Hook-up to achieve high g accuracy y for …
� … small steps (0.5 %)
as well as
� … large steps (50 – 100%)
Consequence after some years…
The stuffing box has reached the tolerable number of cycles (dynamic
stressfactor > 90%) and needs replacement at the next service interval
�R �Result: lt Cost C t optimizatoion ti i t i due d to t smart t “Predictive “P di ti Maintenance”
M i t ”
Step response 0,3%
Step response 50%

Partial Stroke Test
� Especially for on/off applications
(critical ball or butterfly valves, maybe
safety related)
�� Partial Stroke Test without disrupting plant
operation (e.g.: 100% to 90% and
backwards to the operation point)
� Prevent the valve from becoming stuck
� Starting time scheduled or manually
� Step or ramp function
(adjustable ramp to prevent overshoot)
�� Configurable test abortion conditions
� Condensed/test status acc. to NE 107
� Documentable & reliable
�� Goal: maximize the time between full proof
tests -> Cost optimization
� Full Stroke Test over the entire travel range
is always required!
PFD
SIL threshold
test intervall without PST
test tintervall with PST
6 12
18 24
1
PFD = λDU
⋅ TPR
2
months

Partial Stroke Test examples
11. Ramp with low friction
� No noticeable problems
2. Ramp with increased breakaway torque
� Slightly overshooting
3. Ramp with high breakaway torque
� Extreme overshooting could cause problems for the
running process!
� Therefore cancellation conditions travel & drive signal g y
1 2
3

FF specification work for end user benefit
Fi Fieldbus ldb FOUNDATION hhas added dd d end d user requirements i t iinto t
their specifications for interoperable use of diagnostic functions
� FF-912 “Field Diagnostic Profile” according to NAMUR recommendation NE 107
“Self-Monitoring and Diagnosis of Field Devices”
�� FF-906 “Positioner Positioner Transducer Block Block” parameters for diagnosis test
� CYCLE_CNTR, CYCLE_CNTR_LIM, …
� VST_MODE → Partial Stroke or Full Stroke Test
� PST PST_BREAKOUT_TIME, BREAKOUT TIME PST_RAMP_RATE, PST RAMP RATE …

Th Thank k You Y
for your attention!