Field%20Operations

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Field%20Operations

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Title: Field%20Operations

1
Field Operations
2
Field Operations (Real World)

Applicable technology courses, core and
non-core facilities
operations, safety courses are the main thrust
of most training
program. At the end of those training program,
we feel confident that
we are ready to run the plant and cope with
operational upsets and
emergencies.
Once out there in the field, some got lost in
dealing with day to day
events and failed to demonstrate workplace
competency expected.
So many views were offered regarding that
issue. Some
nasty, some polite or politically correct
criticism, most experts says it
is system failure, etc. Probably it is a bit
of everything.
One global company has this unwritten
culture. They expect their
people specifically Experts key staff to
know what to know and what
to look for on their own. Simple enough, but
the problem is
sometimes people hired were not prepared for
that. Some do not
even have a clue.

3
Field Operations

Some simply insisted in practices they
learned in their previous
workplace which may differ from present
workplace practices.
But because of difference in workplace
environment what we
considered acceptable practices may not be the
right thing to do
elsewhere.
Even in the industry we are in, some practices
differ due to many
reasons.
Fortunately in APC, all or most of what we
should know and what to
look for are made available for our perusal.
They were prepared
either as SI or WOI.

4
Field Operations

In addition to our ability to operate the
plant efficiently and safely, putting into
practice those SI and WOI we are expected to
practice
certain work place behaviors. Problem is
nobody tells us.
This module attempts to give you some hints
of those expectations
by way of compiling some work practices and
behaviors which are part of the work culture in
most manufacturing plant.
Module also includes simplified basic
aspects or fundamentals of some specialized
field prepared by a non specialist so that we
will not be intimidated by technical jargon
during formal trainings.
Because we should have reasonable ideas about
field operation, this module can also help us
prompt course facilitators to teach what we more
on what is needed in our job as process
technician.

5
Field Operation

Process Technicians
Process technicians are the equivalent of
plant or process operators in the old days.
Common misconception from outsiders is that
process technician
job is similar to what a TV technician or
the repair man Sony send you to fix your
electronic appliances.
In a manufacturing plant, process
technicians are the man and women who run
operate the plant. Their main task as a group
is to
manufacture/produce product required of
them.
To illustrate what process technicians do,
let us talk about lube oil refining which is a
multi-product plant with similar operating scheme
like ours.

6
Field Operation

Process Technicians (cont)
Normally corporate tells manufacturing
volume of each products
they want for that year based on forecast.
TSD planner prepare a
running plan based on figures supplied by
corporate. Running plan includes scheduling of
raw material, chemical, and everything needed to
produce what the want.
Plant operation, of course, is programmed
based on facilities available/capabilities. Main
thrust is to prepare a running plan sequence that
would minimize slope transition product.
Our job as process technician is to produce
the volume of product
with the spec they want safely and
efficiently on time.

7
Field Operation

Process Technicians (cont)
Plants are usually divided into two main
areas. Main plant which is usually referred as
ISBL or Core plant and OSBL or Non Core area.
Each areas are further subdivided into
several sections. These sections are divided
among the process technicians based on some
criterias.
In most plant, the process technicians is
considered the owner of assigned sections. Hence
he/she is responsible for ensuring that all
applicable rules and regulation were followed by
everybody entering/working in his area. Ensure
that all facilities/equipments under him were in
good running condition including housekeeping
in his workplace.
Of course process technician main key
results area is to come up
with whatever is expected/needed from his
area to manufacture product.

8
Field Operation

Process Technicians (cont)
To illustrate, lets say you are assigned in
the utilities and among your responsibilities is
steam production and cooling water.
- You should be able to treat raw water at
required spec and volume to support your demin
and cooling water system make needs.
- You should be able to produce enough demin
water to support
your boilers
- You should be able to produce enough
steam with the right spec required at the core
plant

9
What They Dont Teach You (And Tell You)

Common perceptions about Process Operator
Heard from a Refinery Manager during an induction
course
Early one Sunday morning his wife decided
that she wants to join his daily morning round of
the plant. The man obliged. No problem after all
he is the boss.
While in the middle of the plant, his wife
told him that she wanted to go the toilet. We do
not have women toilet here, just do what you want
right here, he replied. But dear, there are
some chaps walking around , his wife argued.
Dont worry about them, he replied. Those are
my operators, they dont see, they dont hear,
they dont smell.

10
What They Dont Teach You (And Tell You)

Common perceptions about Process Operator (cont)
Heard from a Refinery Manager during an induction
course
This story was an old, recycled joke about our
profession repeated in
an audience of about 300 cross-posted operating
staff from about 6
countries. Some of us might feel insulted hearing
that joke in an
induction course, but not that crowd. We asked
for more after a big
applause. But the refinery manager replied that
he got to get back to
business. He started his talk with something like
this I think what you want to
hear is something about pay. When is pay day,
holiday and night premium
rates etc, etc, but my job is to orient you gents
about the project. Bear with me
guys. Free lunch will be served.

11
What They Dont Teach You (And Tell You)

Types of Operator
Elsewhere, plant operators classify their co
workers according to work
style. Here are few I had chosen from a
newsletter, I found inserted in
one training material used in preparing this
training module.
Probably, most of the type of operators named no
longer exist in
present day workplace culture, but let us look at
them just the same.

12
What They Dont Teach You (And Tell You)

Types of Operator
Smart Operator
Walk around his area first hour. Sleeps
most of the night, wake up once to take his snack
and back to bed again. Morning comes he produces
his readings (because he is smart unlike some who
had readings at all times, he writes S/D on the
reading sheets whenever his facilities are on
S/D). He performs housekeeping (water flushing)
minutes before the boss comes, ensuring that he
is in a place he can be seen when the boss
arrive.
Oh, yes, he always have a friend who
knows where his bed is, in
case he is needed or the boss decided to
walk around.

13
What They Dont Teach You (And Tell You)

Types of Operator (cont)
2. The Professor
Loves to lecture on trainees and plant
visitors. Keeps correcting
junior operators on the pretext that the
later is not doing
his job according to SOP, what ever SOP
meant to him At the
same time, he lecture the guys theories
learned from University of
Hard Knock he thinks applicable to the job.
To him there is only
one way to do the job right. Do it according
to his SOP. Because
he is the professor whenever trainees join
the plant, people throw
him those guys for on the job shadowing.
Whenever, a trainee fumbles during
assessment, he learned
to reason out that, that is what the
professor taught them, They
usually got away with it. Good laugh for all,
when assessors spread
the story at the CCR the next day.

14
What They Dont Teach You (And Tell You)

Types of Operator (cont)
3. Monkey Operator
He can run all equipments in the plant.
Usually he got what is called
a bible they call it capitulo siete in the
Phil where peculiar
procedures were written. In addition, he got
so many markings out
in the field to assist him.
It is something similar to this Push the top
bottom on the left, next
push the bottom below, a bulb will light,
then push the green bottom
and the machine will run etc.
If equipment failed to runs, he request
maintenance assistance.
He satisfactory performs all routine, but
hopeless when task deviates
from normal. He never fails to do his
readings. Even when plant is on
shutdown, he got one.

15
What They Dont Teach You (And Tell You)

Types of Operator (cont)
3. Monkey Operator
Sometimes, others even call him for help in
starting up machine
which made him think he is the best.
So during yearly assessment he complains to
the boss during
assessment about his grade and talk about
his promotion claiming
he knows all, but was left out for more than
ten years. Once he even
threaten

16
What They Dont Teach You (And Tell You)

Types of Operator
4. Mr Credit Grabber
He is always around in all activities. You
can be sure that he is
holding his handy talkies mouth piece all
the time to makes sure
he communicates with CCR before the man on
the job do it.
Here is a typical example While area
operator is trying to run a
turbine driven pump, Mr. C.G. would start
communicating with CCR
informing the DCS operator and for the bosses
to hear the
progress of the job. The lube oil system is
now circulating, later
Governor is now latch and steam valve is now
being open. Then
Pump is now fully commissioned, it is all
your mate. Thanks,
Raymond (Mr. C. G), excellent job, CCR would
acknowledge.

17
What They Dont Teach You (And Tell You)

Types of Operator (cont)
4. Mr Credit Grabber
Man on the job? Entirely left out of the
picture as they say. He
usually just throw their valve wrench to the
ground out of
prostration, walk away looking for someone to
complain about Mr
C.G.

18
What They Dont Teach You (And Tell You)

Types of Operator (cont)
5. Operator (Typical)
He got the sense of urgency.
He is already at the CCR while the rest of
the gang are still halfway
the premonade. He go straight to main CCR
after getting his
props from his locker, and look for the guy
he is to relieve for
handover. He checks the DCS and discuss
status of his area with
the DCS operator. Before going to the plant he
pass by the Permits
Office to orient himself of works to be
carried in his area that day.
Unlike some, he does not return to the locker
room and waste time
looking around the place for 10 minutes or
pass by the pantry to
inspect, read bulletins he had been reading
daily for the past 3
months nor to gather the latest gossip.

19
What They Dont Teach You (And Tell You)

Types of Operator (cont)
5. Operator (Typical)
He knows what to know and what to look for
He performs his routines with meticulous
attention to details. Note
down concerns, rectify what he can
immediately and discuss with his
supervisor any issue that needs higher up
attention. He performs
housekeeping and do what he can immediately to
eliminate hazard
he noticed instead of just logging them and
waits for someone to
action.
What is bad about him is he never come up
with some idiotic report
to please his boss whose expertise is to blew
up non sense out of
proportion.

20
What They Dont Teach You (And Tell You)

Types of Operator (cont)
5. Operator (Typical)
He often review engineering principles
associated with his facilities
referring to technical book to checks.
Mentally review emergency
procedures normally referring to SI/OI for
confirmation.
He always try to do his best to excel not
necessarily for promotion
but for the sake of learning. This type would
be happy to be promoted
but being an intelligent and realistic person,
he do not expect it,
because he knew he lack the real world core
competencies
whatever that mean. He will eventually make it
if he decides to stay
in a couple of years, and in time he will be
the big boss running the
organization.

21
What They Dont Teach You (And Tell You)

Types of Operator (cont)
5. Operator (Typical)
Off course, he knew the location of all F/G
props in his area, their
functions and design, particularly the
characteristic of detection
element, because he knew that is the key to
proper management of
the system.
He never forget to perform routine
checks/tests on safety equipment,
Prepare WOR as required.

22
What They Dont Teach You (And Tell You)

Types of Operator (cont)
5. Operator (Typical)
He have the sense of ownership
He ensure that he is aware of every
activities in his area. Check all
ongoing work. He satisfy himself that work
permits issued are in
order, stipulations correct even though they
were signed by the boss.
Ensures workers complied with PPE and
requirements of the permit.
He stops work if warranted.
He repeatedly checks on his equipments several
times during the
shift to satisfy himself that everything are
ok while ensuring that all
routines are done and all request from CCR are
complied with.

23
What They Dont Teach You (And Tell You)

Types of Operator (cont)
5. Operator (Typical)
No butterfly in his tummy
Because he works hard and fully aware of what
is going on, he does
not leave CCR when the boss enters nor change
direction to avoid
meeting big guys walking around the plant.
During emergencies he emerged as the leader
directing the show
while his boss keeps tailing him or no where
to be found.
During simulated safety drill he knows
exactly what to do, problem is
sometimes he shout at people doing idiotic
actions and on occasion
can not refrain from laughing seeing stupid
things people are doing.

24
What They Dont Teach You (And Tell You)

Types of Operator (cont)
5. Operator (Typical)
Bad Guy on the Block
He does not mind being tagged as bad guy by
some people as long
as he is doing what are expected of him. He
would not allow people
not wearing the prescribed PPE in his area,
would not tolerate unsafe
acts, police his area to ensure people are
following company
regulations no matter who they are. He would
even sent you back to
CCR to sign the visitor log book if you
forget to do so. He would not
allow maintenance to close completed work
permits if housekeeping is
not done reasonably well.

25
What They Dont Teach You (And Tell You)

Types of Operator (cont)
5. Operator (Typical)
He does not hesitate to challenge anyone when
he thinks best
efforts/options were not being carried out
while performing activities in
his facilities.

26
What They Dont Teach You (And Tell You)

Types of Operator (cont)
5. Operator (Typical)
Model Operator
How come? He is the bad guy on the block, do
not support some
boss idiosyncrasies, challenge people,
insist that everybody follows
rules, checks even his boss job, stops
ongoing work if he feels
necessary, act as if he own the plant, and at
the same a model
operator.

27
What They Dont Teach You (And Tell You)

Types of Operator (cont)
In the former BPC forerunner of APC, there were
about 80 process technicians
And probably 50 maintenance tech. I like to think
that all of them developed a
work culture attributed to the last type I called
operator (typical). In the
newsletter they are called mga krus- why ?, you
might be asking your self.
Now almost all of them are doing good elsewhere.
Despite their relatively shorter
work experience, they were able to compete with
others with 10 or more years of
experience. Similarly all the mga krus in the
work place where that newsletter
was published were pirated by a similar firm with
compensation 6 times higher
plus benefits that is the best in the land at
that time.

28
Pre-com (General)

Pre-commissioning assurance of systematic
conformity to design
spec.
1. Pre-com encompass such requirement as
Punch list and check out of system
Static/de-energized tests on equipment
(calibration, loop checks and logic checks of
inst, cold alignment and rotational checks of
motors, testing of electrical equipments etc)
Flushing/cleaning of vessels/pipes
Leak testing
Test running all utility systems
Test running of all instrumentation including
DCS, ESD and F/G systems
Test running of all electrical systems
Test running of all rotating equipment
Test running of all power generation systems
Performance testing of telecom systems
Testing of the accommodation module in its
entirely

29
Pre-Com (General)

Pre-com (cont)
Pre-start up Technical Safety Audit during the
testing and pre-com phase, Owner shall perform a
pre-start up TSA to confirm that the production
facilities and associated facilities are ready
for commissioning and initial operation.
After completion of pre-com and recommendation
from audit, contractor shall apply to owner for
the issue of a Certificate of Mechanical
Completion, issue of w/c is required prior to the
commencement of the commissioning of facilities.
2. Mechanical completion shall means completion
of pre-com activities with the punch lists of
outstanding items agreed by the parties.
All essential utilities, life support
system, carnage, electric power (supply
generation distribution), drainage and
firewater shall be commissioned as an integral
part of pre-com prior to declaring mechanical
completion
The plant status reached at the end of
pre-com is defined as Mechanical Completion or
Ready for Commissioning

30
Pre-Com (General)

3. Commissioning during this phase, the
facilities, systems and equipment items are
checked and prepared for the commencement of
operations and oil in.
Mechanical completion
Electrical commissioning
Instrument commissioning
Telecommunication commissioning
Pipeline and Sub-sea Cable commissioning
HVAC commissioning

31
Pre-com (General)

Activities undertaken at this time include
Dynamic verification that each equipment items
performs properly (motor run-in uncoupled,
integrity checks of inst loops, electrical
breakers operations etc)
Mechanical preparation, actual running and on
line tests of plant utilities, and whenever
practical, main process equipment being run in a
closed loop condition.
Preparation of al systems so as to be ready for
the introduction of hydrocarbons such as piping
dry out, inerting, charging of various chemicals
and refractory dry out.
Lubrication of equipment as required.

32
Pre-com (General)

Completion of commissioning is defined as READY
for START UP at
w/c point the systems are ready for the
introduction of hydrocarbon.
Contractor shall apply and owner shall issue
Certificate of
Commissioning Completion only if the contractor
performed to the
satisfaction of owner the testing and
commissioning of all parts of the
FACILITIES in accordance with the approved
Commissioning Manual.
The punch list items have been cleared
The completion of the maintenance activities,
including maintenance activities that may have
commenced during but not completed before
commissioning
The submission of all required deliverables
The satisfactory completion of all formal
training
Start up and Performance Testing since the
start up of utilities would have been carried out
during commissioning, the actual start up begins
with the introduction of hydrocarbons into the
facilities as follows

33
Pre-com (General)

Oil in
Bringing the plant into operation and its steady
state
X hours test run (capacity performance testing)
XX days Production Performance Testing

34
General Pre-com Activities

System cleaning
Running test
Operational tightness test
Air freeing
Drying out
Catalyst, dessicant, chemical loading

35
Pre-com (general)

System cleaning
1. Air blowing
- A pipe cleaning method utilizing kinetic
energy of air flow
Method
Method A - air accumulation method
Method B - direct blowing method
Method C - scavenging run of compressor/blower
Application
Chemical lines
Instrument/plant air lines
Nitrogen lines

36
Pre-com (General)

Air blowing (cont)
Hydrogen lines
LPG/ethylene/butane lines
Reactor and gas loop lines
Powder conveying lines
Pellet conveying lines
Flare and vent lines
Solvent, R20, and R21 lines
Catalyst lines
Catalyst activator lines

37
Pre-com (General)

2. Steam blowing
- Steam blowing utilizes the kinetic energy
of steam flow.
Since blowing and cool down of the pipe
concerned are repeated
during steam blowing, rust, weld slag or
spatter become liable to
peel off from the pipe surface due to the
repetition of expansion and
contraction of the pipe.
Application
Medium pressure steam lines
Low pressure steam lines

38
Pre-com (General)

3. Power flushing/water circulation
- A pipe cleaning method utilizing kinetic
energy of water
Method
Pipes are flushed using the permanently installed
pumps connected to the pipe but running on water
instead of the normal process fluid
Flushing velocity must exceed the maximum process
velocity during normal operation
Application
It is basically applied to the following carbon
steel pipes

39
Pre-com (General)

Power flushing (cont)
Raw water/filtered water service lines
Potable water lines
Demineralised water/boiler
Cooling water supply/return line
Condensate lines
Fire water lines
Process water lines

40
Pre-com (General)

Mechanical cleaning
- manual cleaning. Wire brushes, hand
grinders, broom for sweeping or industrial vacuum
cleaners are used.
Application
The following are manually cleaned before using
or closing them for
process use
Vessels
Column
Drum
Hopper
Tanks
Pits
Large pipes, etc.

41
Pre-com (General)

Running Test
Mechanical run in of compressors
- To check mechanical performance such as
vibration, noise, heat generation on bearing of
compressor systems including drivers and
compressor auxiliary functions during start up or
initial operation.
Application
Mechanical run in shall be conducted for all
compressors. The recommended test period of
mechanical run is about 4 hours.
Fluid used nitrogen or actual gas.

42
Pre-com (General)

Running Test
Mechanical run in of pumps
- To check mechanical performance of pump
system including drivers and pumps auxiliaries
using either water, lube oil or gas oil as
pumping medium. Vibration, heat generation on
bearing are checked.
This testing enables early detection of
machine problems and is intended to minimize
problems during operation.
Application
In principle, process pumps except auxiliary
pumps for lubrication shall be mechanically run
in with water or actual fluids.

43
Pre-com (General)

Running Test (cont)
Some pumps can be operated with water, while
other pumps can only be operated with actual
fluid due to reasons listed below
1. Overload of motor
Overload will occur during run in with
water for pumps which
handle fluid of lower specific gravity
than that of water. Throttling
the pump discharge flow rate to avoid
overload may cause
another problem that the minimum
allowable discharge flow rate
can not be maintained.
2. Water contamination not allowed
Remaining water may enhance corrosion,
abnormal reaction with
actual fluid, contamination,
potentiality of icing/hydrate formation
and the likes at or after start up.

44
Pre-com (General)

Running Test (cont)
3. Circulation route not practical
Appropriate water circulation loop can
not be realized. Once
through run in route is planned only for
pumps with normal
flow of less than 1 m3/hr.
4. Difficult post work
drain out or dry out operation of
piping/pumps as a post work of water run in is
considered to be a very big job giving an impact
on pre-com schedule.

45
Pre-com (General)

Running Test (cont)
3. Blower/fan mechanical run in
- To check machine for vibration, noise,
heat generation on
bearing of blower/fan system including
their drivers to confirm
motor performance.
Application
- All blowers/fans

46
Pre-com (General)

Operational Tightness Test
- Checking entire plant or part of the plant
for leakage. In general, plant handles
combustible, poisonous or other dangerous
materials.
Where tightness is lacking, material handled
will leak resulting to disasters. In some cases,
operation can not be continued. Further the
leakage of handled material will result to large
economic loss.
To prevent leakage during operation tightness
test is carried out to confirm that the plant
complies with the required tightness before start
up.

47
Pre-com (General)

Operational Tightness Test (cont)
Method
- The system is pressurized with compressed
air or nitrogen (or steam in some system). If
pressure holds for 2 hours, system is considered
leak free.
- Detection of leak is done using soapsuds.
All flanges should be taped to give better
results.
Application
- The test shall be performed for all piping
and equipment processing/handling
hydrocarbon/hydrocarbon container within process
units, utility/offsite facilities, marine
facilities.

48
Pre-com (General)

4. Air freeing
- To remove potential hazard of forming an
explosive mixture when combustible hydrocarbons
are mixed with air (substantially oxygen).
Method
- Nitrogen or steam is introduced from one
end of the system or equipment and vented from
the other end until specified oxygen level is
attained.
Application
- All hydrocarbon process pipeline/equipment
and flammable
chemical lines within the process unit.
- Pipe/equipment for handling or transferring
fluids in utility /offsite
/marine area facilities.

49
Pre-com (General)

5. Dry out
Refractory drying carried out by heating
the furnace (or
equipment with refractory) to remove
moisture and to stabilize the
crystalline structure of the refractory
under a previously specified
temperature-time program.
Circuit drying
1. Normal drying carried out by blowing
air or nitrogen to remove
moisture remaining to agreed specification.
2. Vacuum drying Carried out by vacuum
pump etc to remove moisture remaining to agreed
specification.
Method
Drying will be carried out as follows
1. Drain out carried out after hydraulic
test or water flushing until no water drains out
from low points.
Application
- All hydrocarbon process pipeline/equipment
and flammable
chemical lines within the process unit.
- Pipe/equipment for handling or transferring
fluids in utility /offsite
/marine area facilities.

50
Pre-com (General)

5. Dry out (cont)
Method
Drying will be carried out as follows
1. Drain out carried out after hydraulic
test or water flushing until
no water drains out from low points.
2. Drying out with air preliminary drying
out shall be carried out
with air during air blowing.
3. Drying out with nitrogen final drying
out shall be carried out with nitrogen during air
freeing
Application
- All system where moisture would interfere
with operation, cause
icing and corrosion.

51
Pre-com (General)

6. Catalyst, desiccant, chemical loading
- Load above materials into vessels prior to
commissioning
Method
Loading varies and are done in accordance
with specific or
applicable practice.
Application
- Where applicable

52
Permit to Work

Monitoring of the PTW
One of the daily routine tasks of operation
technicians is to monitor the PTW in her/his area
of responsibility. Below are some general guides
associated to this task
- He/she should be aware of all works
being carried out in his area.
- Ensure that all works are covered with
required PTW
- Do permit spot checks and ensure that
1. Relevant hazards are correctly
identified on the permit
2. Permits and other associated
documents are displayed at the
work site
3. Documentation complete and authorized
correctly
4. Specified safety equipment in place,
in good condition and
being used correctly

53
Permit to Work

Monitoring of the PTW (cont)
5. Specified precaution adequate and
being implemented
6. Work force fully understand
requirements/details of permit
- Ensure that all works are stopped during
emergency or whenever
required
- Stop work when warranted
- Ensure that proper order and
housekeeping are maintained at all
time

54
Override

Most modern plants are equipped with
safeguarding system to protect operations, plant
and investment. In recent years, many companies
have incorporated the principles of depressuring
or instrumented shutdown of key equipment as a
means to control a release and avoid the
actuation of pressure relief devices.
The safety/emergency and operation interlock
system are some of the commonly employed
safeguarding system.
Most facilities are provided with Fire and
gas detection system
to detect gas release or fire. In addition to
sounding alarm some
are provided with extinguishing means which
activates upon
detection.

55
Override

- Interlock activated when a certain
parameter go beyond a set
operating envelop.
- Fire detection system activate when it
sees fire
- Gas detection system activate when it
sense gas release
- Most PLC programs would abort if
requirements of next ladder
is not satisfied
Very convenient and helpful in our job, but
those safeguarding system can give you temporary
inconvenience (like causing total shutdown of
the plant in the case of some facilities). In
general we are not suppose to play with them, but
there are exceptional occasions wherein we should
defeat these system to prevent unwanted incident.

56
Override

In most of the modern facilities, the root
cause of most shutdown and waste of productive
time can be traced to problem associated with
safeguarding system.
Examples
- Activation of interlocks during
maintenance resulting to shutdown
can be due to failure to defeat or
override system at the right time
- Waste of produce and environmental damages
due to failure to
restore defeat after completion of
instrument PM.
- Damage to equipment and in some case lost
of whole plant
and agonies can be caused by unserviceable
safeguarding
system.
- Facility shutdown and/or work stoppage due
to activation of F/G
detection system can be caused by failure
to deactivate them when
necessary

57
Override

Out there in the field as owner of the
plant, it is our responsibility
to manage those safeguarding system
intelligently. Standing and Operating
Instructions are in place to guide us, but it up
to us to decide when to put defeat/restore defeat
in those safeguarding systems.
In order to do so, we should
- Know locations and characteristic of F/G
safeguarding system in
the workplace
- Know systems provided with interlock,
their architecture and logic

58
Process Automation

Courses in instrumentations, PLC etc are
part of our general training, but it was thought
that it is very helpful that introductory course
are provided by an OPERATIONS STAFF to peers
prior to attending those courses in order to
clear the groundetc. It is considered very
useful
to have an idea of what you want to know
for the sake of learning, what are relevant to
your task, particularly those you will encounter
in your present workplace.
Clearing the ground
Look at this (extracted from Foxboro Process
Automatic Course)
Concept of process
1. Production viewpoint
Process is generally thought of as a
place where materials and,
most often, energy come together to
produce a desired product.

59
Process Automation

2. Control viewpoint
From a control viewpoint, the meaning is
more specific. A process is
identified as having one or more
variables associated with it that are
important enough for their values to be
known and for them to be
controlled.
On the next slides, we will attempt to
reconcile both viewpoints to be
able to and/or cope i

60
Process Automation
Signal to control room

Signal from control room
TT
Steam
Hot water
Heat Exchanger
Cold water
Condensate
1.A. Process
Manipulated variable
Process
Controlled variable
Load variable
1.B. Variable
Heat exchanger represent a simple process
61
Process Automation

Referring to Fig. 1A, we have only one variable
to maintain the temperature of the hot water in
this process. In this example, the control system
manipulates the position of a steam valve.
However the temperature of the water depends not
only on the position of the steam valve but also
on the flowrate of the water, its inlet
temperature, the enthalpy of the steam, the
degree of fouling in the exchanger, and the
ambient temperature.
Above illustrates controlled, manipulated and
load variables
Those are the three categories associated with
every process under control (Fig. 1B)

62
Process Automation

What they want us (operations) to be aware of
is that the whole process is not simply
manipulating the position of the steam valve to
heat the water. It is more than that.
To support above, let us look at how Honeywell
define process. Honeywell define as the
collective functions performed in and by the
equipment in which a variable is controlled.
Thus the term process
includes everything that affects the
controlled variable, other than the automatic
controller.

63
Process Automation

1. Controlled variables
These are the parameters that indicate
product quality or the operating condition of the
process. Example are
- pressure
- level
- temperature
- pH
- specific gravity
- density
- composition
- moisture content
- weight
- speed
- other variables depending on the
process