TABLE OF
CONTENTS
1 PURPOSE
2 SCOPE
3 REFERENCE, CODE &
STANDARD
4 DEFINITIONS
5 RESPONSIBILITY
AND AUTHORITY
6 WORK PROCEDURE
7 SAFETY
8 QUALITY CONTROL
1
PURPOSE
The
purpose of this procedure is to specify responsibilities and describe the
steps
Instrument Calibration work for United Steel Company (SULB) Project.
2 SCOPE
This method statement (M/S) shall be applied to Instrument Calibration
work.
3 REFERENCE, CODE & STANDARD
3.1 Subcontractor document
3.2 Work index, symbol and detailed drawing
3.3 Process Control And Automation Engineering
Standard Specification.
European
(IEC and EN) standards shall be adopted throughout,
unless otherwise Specified in the technical
specification.
4 DEFINITIONS
4.1 Within this document following
definitions shall apply.
OWNER / COMPANY
CONTRACTOR
SUBCONTRACTOR
PROJECT
5 RESPONSIBILITY
AND AUTHORITY
5.1 Site
Manager
5.1.1 Site manager bears the responsibility and
authority on work and quality related to this method statement.
51.2 Site manager approves work plans.
5.2 Construction Superintendent
5.2.1 A construction Superintendent bears the
responsibility and authority to train their staff and subcontractor’s after
preparing work plan according to this method statement.
5.2.2 A construction team manager takes the
responsibility of all Instrument calibration work execution and preparation.
5.3 Construction Supervisor
5.3.1 Construction Supervisor shall execute
inspections and tests to secure quality materials, take adequate measures,
manage results as quality records, and utilize checklist.
5.3.2 Construction supervisor bears the responsibility
of Instrument Calibration according to the dimensions specified in
specifications or drawings, and submits reports to the owner for approval
5.4 Quality Manager
5.4.1 Site Quality Manager is responsible for
management and supervision of implementing inspection work as specified in this
method statement.
5.4.2 Inspection request to QC when portions of
the work are ready for inspection, as depicted in the ITP’s.
5.4.3 Responsible for preservation and
maintenance of equipment at site.
6.0 INSTRUMENT CALIBRATION PROCEDURE
6.1 General
Requirements
6.1.1 All instruments in a loop are calibrated,
installed and inspected prior to commencing loop check in accordance with the
applicable procedures and specifications.
6.1.2 Ensure that all procedures, IFC drawings, specifications,
manufacturer’s instruction manual and other relevant references are
available prior to commencing any activities.
6.1.3 Special tools (as
applicable) and calibration equipment to be used shall bear a valid calibration certificate. All Calibration equipments shall be initially
calibrated & periodically
checked.
6.1.4 Calibration of instruments shall be carried
out in accordance with OWNER
specification & procedure and Manufacturer’s Instruction Manual.
6.1.5 Particular attention shall be observed when
connecting electrical power supply to electrical and electronic instruments
ensuring its correct voltage, frequency, polarity and grounding.
6.1.6 Ensure that there is sufficient available
qualified & competent Instrument
Calibration Technician to conduct the required instrument calibration and
works.
6.1.7 All calibration shall be recorded on
approved forms, signed, dated and approved by OWNER, Keep in QC Section, and incorporated in the Inspection Record
Books.
6.2 Calibration
Room (Workshop) Facility Requirements
6.2.1 A fully equipped instrument calibration
workshop and it is intended only for calibration works which is required for
instrumentation.
6.2.2 Instruments shall be calibrated in a clean,
dry and air-conditioned calibration workshop. Ensure daily housekeeping before
and after worked. Use appropriate vacuum cleaner and rugs to keep away dirt /
foreign materials.
6.2.3 Always ensure that the calibration
facilities must be orderly and systematically arranged. It should also be
equipped and complete with correct electrical
and pneumatic supplies. A stable supply of clean dry air must be provided for
instrument air and pneumatic signal generation.
6.3 Calibration Procedure
6.3.1 Calibration for each kind of instrument
shall be covered by individual Application for
Inspection (AFI) form and be witnessed in accordance with
Inspection Test Plan (ITP).
6.3.2 To ensure instrument operability, remove all
shipping stops, check pointer travels and verify capability of instrument to
measure, operate and stroke in the direction and manner required to the process
application.
6.3.3 Instruments shall be checked to ensure that
there is no sign of physical damage upon receipt at site prior to
calibration. Any damage found shall be recorded in Non Confirmation Report (NCR) and shall be handled in accordance with NCR
procedure.
6.3.4 Instruments shall be identified by tag
number and checked against its corresponding data / specification sheet,
ensuring particular attention that it is supplied with the correct calibration
range. All name plate details shall be noted on the calibration data sheet.
6.3.5 Maintain an Instrument Calibration Log for
each piece of test and calibration equipment. Valid calibration stickers must
be fixed to the equipment and calibration certificates available for each item.
6.3.6 Calibration shall be done as per
manufacturer’s instruction, where available. Zero, span, range adjustments,
repairing and modification of instruments to be carried out only after getting
permission from OWNER and added
updating to data sheet specification.
6.3.7 For all instruments / gauges calibration
where applicable, five (5) point testing method shall be followed, say 0%, 25%,
50%, 75% and 100%. After completion of each calibration, the instrument shall
be attached with a calibration sticker bearing the date of the calibration and
the initials of the witnessing parties. The following colour code stickers
shall be applied:
a)
Blue - Pre-installation
Tested (Calibrated)
b)
Yellow - Pressure
Tested
c)
Green - Cables
Tested
d)
White - Pre-commissioned
e)
Red - Test Failed (written message is attached the
cause of failure)
6.3.8 This identification shall be shown on all
components in the loop making all personnel aware of the current status
of any installation.
6.3.9 All instruments are to be calibrated and
adjusted in both rising and falling directions until accuracy is within the
specified limits.
6.3.10 Fluid introduced to instrument bodies for
the purpose of calibration shall be compatible with the fluidized material of
the instrument and the fluid with which the instrument will be filled during
normal operation.
6.3.11 Fluid shall be drained after calibration,
and if necessary, blown dry with dry air or nitrogen. Any air system, permanent
or temporary used must be dry and clean and shall be blown down thoroughly before using. In case permanent
instrument air is not available, nitrogen cylinder as a temporary air source.
6.3.12 Seal all connections and entries to prevent
moisture and dirt.
6.3.13 No test shall be carried out on electronic
instruments until an adequate warm-up period has elapsed as per Vendor’s
recommendation. (Ex. EJA Transmitter more than 5 minutes, YTA Transmitters more
than 3 minutes).
6.3.14 A 100% calibration check is required for all
transmitters prior to installation.
6.3.15 Bench test for smart transmitters shall
include a configuration check out. The following configuration parameters, as a
minimum, shall be set or checked against the instrument data sheet:
a) Software Tag
b) Calibration
Range
c) Output Unit
e) Output Type ( FF/Hart)
d) Sensor Type (Temperature transmitter only)
f) Damping Value
g) Transfer Function (linear / square root)
Note : Refer to other parameter specification in specification
data sheet,
where applicable specifically for
FF parameter
All parameters can be read and written using FF/HART
communicator.
6.3.16 During configuration check full tag number
shall be input into descriptor field.
6.3.17 Incoming
Instrument Procedure:
a) Instruments to be bench calibrated will be
withdrawn from warehouse and stored in the Calibration shop “incoming shelves”.
b) Calibration shop Foreman will keep a record
book to monitor incoming and outgoing calibrated instrument.
c) Instrument Engineer / Supervisor shall
checked and ensure that copies of Manufacturer’s Instructions (If applicable)
and Test Certificates, Instrument Data / Specification sheets are available and
latest revisions ( IFC ).
d) QC Supervisor / Calibration Foreman will
prepare Calibration Sheets or incoming instruments.
6.4 Detail
Calibration Method for each type of instruments
6.4.1 Flow Instruments
6.4.2 Differential Pressure Flow Type Transmitter
Prefer to be Bench
calibrated
Hook
up testing equipment as shown below:
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Differential Pressure Flow Type Transmitter
a) Vent low side.
b) When no pressure is applied to the high side,
the transmitter should be 0% of output range. If it is not, adjust zero
adjustment until the output indicates 0% by FF/HART
communicator.
c) Increase input signal to full range (100%) as
shown in the specification sheet. The transmitter output shall be 100% of its
range. If it is not, adjust span adjustment by FF/HART
communicator.
d) Recheck zero after span adjustment. Repeat
until both reading are correct.
e) Check output signal and scale readings at 0,
25, 50, 75 & 100% of the input signal instrument range (Measuring DP range)
with signal rising and falling.
f) Corresponding mA or FF output signals is as
follows:
Square-root
extraction from transmitter is usually 0%, 25%, 50%, 75%, 100%. Using
FF/HART communicator to enter the tag number/ scale range
(LRV, URV)
Damping,
/Display range. Refer to other parameter specification in specification
data sheet ,where applicable
specifically for FF type.
g) Every output reading shall be within error
limit specified by manufacturer. If it is not, adjust linearity adjustment and
repeat steps c) thru f) until output reading corresponds with input signal
within acceptable error limit. FF/HART
communicator will be utilized for adjustment.
h) If the
instrument is equipped with high/low range limit mechanism, adjust it to meet
proper
requirements. After the initial calibration
test, the high and low pressure sides of the
meter element shall be subject, in turn, to
a static pressure equal to the
maximum expected working pressure. The
calibration test shall then be repeated to
ensure that the results are unaffected by
the static pressure loading (Refer to spec.
for the
static pressure test).
i) After the tests have been completed, the
instrument shall be identified with a colour sticker.
j) Test results / readings will be filed and
recorded on applicable calibration form including
vendor specific
requirement/information.
6.4.3 Vortex Flow Meter
Hook
up testing
equipment as shown below:
Vortex Flow Transmitter
a) Visual check and smart transmitter
configuration check shall be performed.
b) Check the tag
number, Scale range (LRV, URV),Units and damping ect.
Note : Refer to other parameter specification in specification
data sheet ,
c) FF/Hart
communicator should be used for configuration check.
d) After the tests have been completed, the
instrument shall be identified with a colour sticker.
f)
Test results / readings will be filed and
recorded on applicable calibration form including
vendor specific
requirement/information.
6.4.4 Ultrasonic Flow Meter
Hook up testing equipment as
shown below:
Ultrasonic flow meters
a) Visual check of transmitter configuration
shall be performed.
b) Check the tag
number, Scale range (LRV, URV),Units and damping ect.
Note : Refer to other parameter specification data sheet
,
c) FF/Hart
communicator should be used for configuration check.
d) After the tests have been completed, the
instrument shall be identified with a colour sticker.
e) Test results / readings will be filed and
recorded on applicable calibration form including
vendor specific
requirement/information.
6.5 Pressure
Instruments
6.5.1 Pressure
Transmitter
Prefer to be Bench calibrated
Hook up testing equipment
as shown below: 
Pressure
Transmitter
Note : Refer
to other parameter in specification data sheet
a)
When no pressure is applied to the
instrument, the output of transmitter should be 0% of its range. If it is not,
adjust zero adjustment until the output indicates 0% of its range by FF/HART Communicator.
b)
Increase input signal to full range (100%)
as shown in the specification sheet. The transmitter output should be 100% of
its range. If is not, adjust the span by FF/HART
communicator.
c)
Recheck zero after span adjustment. Repeat
until both reading are correct.
d)
Check output signal and/or scale readings at
0, 25, 50, 75 & 100% of the instrument range with signal rising and
falling.
e)
Every output reading shall be within error
limit specified by manufacturer. If it is not, adjust linearity adjustment and
repeat steps a) to d) until output reading corresponds with input signal within
acceptable error limit.
f)
After the tests have been completed, the
instrument shall be identified with a colour sticker.
g)
Test results / readings will be filed and
recorded on applicable calibration form including vendor
specific requirement/information.
6.5.2 Differential Pressure Transmitter
Prefer to be Bench Calibrated
Hook up testing equipment as shown below:
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Differential
Pressure Type Transmitter
a)
Vent low side.
b)
When no pressure is applied to the high
side, the transmitter should be 0% of output range. If it is not, adjust zero
adjustment until the output indicates 0% by FF/HART
communicator.
c)
Increase input signal to full range (100%)
as shown in the specification sheet. The transmitter output shall be 100% of
its range. If it is not, adjust span adjustment by FF/HART communicator.
d)
Recheck zero after span adjustment. Repeat
until both reading are correct.
e)
Check output signal and/or scale readings at
0, 25, 50, 75 & 100% of the instrument input signal range (Measuring DP
range ) with signal rising and falling.
f)
Every output reading shall be within error
limit specified by manufacturer. If it is not, adjust linearity adjustment and
repeat steps c) to f) until output reading corresponds with input signal within
acceptable error limit. FF/HART
communicator will be utilized for adjustment.
g)
If the instrument is equipped with high/low
range limit mechanism, adjust it to meet proper requirements. After the initial
calibration test, the high and low pressure sides of the meter element shall be
subject, in turn, to a static pressure equal to the maximum expected working pressure.
The calibration test shall then be repeated to ensure that the results are
unaffected by the static pressure loading.
h)
After the tests have been completed, the
instrument shall be identified with a
colour
sticker.
i) Test
results / readings will be filed and recorded on applicable calibration form
including vendor Specific
requirement/information..
6.5.3 Pressure &
Differential Pressure Gauges
a)
Pressure and Differential gauges shall be
checked by means of Hydraulic Gauge Comparator. This is a means of testing a
gauge against a Standard pressure gauge.
b)
The gauge Comparator is firmly fixed to a
bench. A test gauge with range comparable to the gauge under test is fitted to
one branch of comparator. The gauge to be tested is fitted to the other branch
and the hand pump on comparator in order to check the gauge readings against
the test gauge. Reading shall be checked for pressures corresponding to 0, 25,
50, 75 and 100% of the range of the gauge under test. Actual gauge reading
shall be noted for both rising and falling.
c)
Test gauges shall have an accuracy of or
better than 0.25% of full scale and shall be periodically checked for accuracy
against a dead-weight tester.
d)
Low side on differential pressure gauge must
be vented to atmosphere.
e)
After the initial calibration test, the high
& low-pressure sides of the PDI shall be subjected in turn to a static
pressure equal to the maximum expected working pressure. The calibration test
shall then repeated to ensure that the results are unaffected by static
pressure loading.
f)
After the tests have been completed, the
instrument shall be identified with a colour sticker.
g)
Test results / readings will be filed and
recorded on applicable calibration form including vendor
specific requirement/information.
6.6 Level Instruments
6.6.1 Differential Pressure
Type Level Transmitter
Prefer to be
Bench calibrated.
Hook up testing equipment
as shown below
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Differential
Pressure Type Level Transmitter
Note: Hook up Testing Procedural Step: (Refer
to Differential Pressure Type Transmitter on the above Fig 10.4.2.4)
6.6.2 Level Switch
Support the level switch on a test stand vertically
Hook up testing
equipment as shown below:
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Level
Switch
Vibration Type:
a)
Check switching action with ohmmeter
(multimeter) while simulating level condition. Actual operating fluid preferred
as a testing fluid, if the fluid available, similar characteristic (specific
gravity or conductivity) fluid should be used.
b)
Marked switching level on level switch so
that mark can be used as a reference during field installation.
c)
Test results / readings will be filed &
recorded on applicable calibration form.
6.7 Temperature Instruments
6.7.1 Thermocouple Type Temperature Transmitter
Prefer to be Bench calibrated.
Determine
mV value at 0, 25, 50, 75 & 100% of temperature range from temperature
conversion table.
Hook
up testing
equipment as shown below:
Thermocouple Type Temperature
transmitter
Types of Thermocouple: K, T, J, E,
R, S,…ect.
a) If the transmitter is equipped with type
and/or range changing jumpers or switches,
put
them on proper position.
b)
Measure ambient temperature and determine mV
value from the conversion table.
c)
Calculate calibration value at each
calibration point using the formula below:
mVcal = mVoper. – mVamb.
where:
mVcal = millivolt value
of calibration
mVoper = millivolt
value of operating temperature
mVamb = millivolt value
of ambient temperature
d) Hook
Simulate 0% of calibration signal and check output. The output should be 0% of
its range. If it is not, adjust zero by FF/HART
communicator until correct value is obtained.
f) Simulate
100% of calibration signal and check output. Adjust span by FF/HART communicator when error is found.
g) Recheck
zero after span adjustment and repeat step d) to f) until both are correct.
h) Check
output at 0, 25, 50, 75 and 100% of input range with signal rising and falling.
Every output reading shall be within error limit. If it is not, adjust
linearity adjustment and repeat steps d) to f) until every output reading
correspond with input signal within acceptable error limit.
i) Ambient
temperature effect is to be checked, change ambient temperature of the
instrument and check output change.
j) If
the instrument is equipped with burnout option, check this function by opening
the input terminal and check output changing. When improper burnout action is
observed, correct it by changing jumper or switching in accordance with the
manufacturer’s instruction.
k) After
the tests have been completed, the instrument shall be identified with a colour
sticker.
l) Test
results / readings will be filed and recorded on applicable calibration form.
6.7.2 RTD Type Temperature Transmitter
Prefer to be Bench calibrated.
Determine RTD (Resistance Temperature
Detector) type and operating conversion table.
Determine
resistance value at 0, 25, 50, 75 & 100% of input range from temperature
conversion table.
Hook up testing equipment as follows:
RTD Type Temperature Transmitter
a)
Simulate 0% of input signal by adjusting
decade resistance box and check output. Adjust zero by FF/HART communicator until 0% of output is
obtained.
b)
Increase input signal up to 100% of its
range and check output. The output shall be 100% of its range. If it is not,
adjust span by FF/HART communicator.
c)
Recheck zero after span adjustment and
repeat until both are correct.
d)
Check output at 0, 25, 50, 75 and 100% of
input range with signal rising and falling. Every output reading shall be
within error limit. If it is not, adjust linearity adjustment and repeat steps
a) to f) until every output reading correspond with input signal within
acceptable error limit.
e)
After the tests have been completed, the
instrument shall be identified with a colour sticker.
f)
Test results / readings will be filed and
recorded on applicable calibration form.
6.7.3
Resistance Temperature Detector
a)
Sheath shall be removed from the thermowell
and checked for damage.
b)
Resistance between terminals shall be
measured and recorded. Measured resistance value shall be compared with the
value obtained from the conversion charts correspondent to ambient temperature.
If accuracy is within the required limit, it is acceptable.
c)
Resistance between terminals and sheath to
be checked. If sheath and terminals are isolated, it is acceptable.
d)
After testing, sheath shall be replaced in
their thermowells, it is important to ensure that the sheath is “bottomed” in
the thermowell.
e)
Test results / readings will be filed and
recorded on applicable calibration form.
6.7.4 Thermocouple Element
a)
Sheath shall be removed from the thermowell
and checked for damage.
b)
Continuity between terminals shall be
checked. If continuity is confirmed, it is acceptable.
c)
After testing, sheath shall be replaced in
their thermowells, it is important to ensure that the sheath tip is “bottomed”
in the thermowell.
d)
Test results / readings will be filed and
recorded on applicable calibration Form.
6.8. CONVERTER
6.8.1 Current to Air
Converter (I/P)
Hook up testing equipment as shown below:
mA / FF Signal
I/P Converter
a)
Inject 0% of input signal and check output.
Adjust zero when error found.
b)
Inject 100% of input signal and check
output. Adjust span when the output deviates more than the error limit from
100% of its range.
c)
Recheck zero after span adjustment and
repeat steps a) to c) until both are correct.
d)
Simulate input signal 0, 25. 50, 75 and 100%
and check output (0.2kg/cm sq., 0.4kg/cm sq., 0.6kg/cm sq., 0.8kg/cm sq. and
1.0kg/cm sq.) with input rising and falling. Every output reading shall be
within error limit. If it is not, adjust linearity and repeat a) to d) until
desired input-output is obtained.
e)
After the tests have been completed, the
instrument shall be identified with a colour sticker.
f)
Test results / readings will be filed and
recorded on applicable calibration Form.
6.9 Control
Valve
6.9.1
General
a)
Calibration test will be carried out in the
instrument workshop for 4” to 6” or smaller valves. For large size valves
calibration will be done in site, after the valve has been installed in the
line. Test should not be carried out until the valves in its final operating
state, ex., after line flushing operations and hydrostatic tests have been
completed.
b)
Hydrostatic testing and line flushing should
be carried out with the valve removed.
c)
Check that the valve and data plate agree
with the control valve specification.
6.9.2 Diaphragm actuator spring adjustment
(Bench Set).
a)
The diaphragm actuator shall be checked thru
the following items :
- Size and type
- Stroke and range
- Spring range
b)
Adjust pneumatic signal so that the valve
close slowly, and stop when the valve fully closed.
c)
Read the pneumatic signal value and compare
it with the actuator range. If the difference is greater than 2%, adjust spring
adjusting nut and repeat steps c) to d) until the desired value is obtained. If
the desired value cannot be obtain with spring adjustment, change stem length
by adjusting connector assembly and repeat steps c) to d).
d)
Adjust pneumatic signal so that the valve
open slowly, and stop when the valve is fully opened.
e)
Read the pneumatic signal value and compare
it with the actuator range. If the difference is greater than 15%, change
spring and recheck closing and opening.
f)
Adjust position indicator scale so that the
indication works correctly.
g)
Inject pneumatic signal 0, 25, 50, 75 and
100% of its range and read valve position with signal rising and falling.
h)
Speed of stroking time from full open to
full close is to be checked, if required.
6.9.3 Other Type Actuator
a) The actuators other than diaphragm type shall
be tested for stroking and failure action in
accordance with manufacturer's instructions.
In addition the following items shall
be checked before the stroke check
(positioner calibration).
A. Piston Type Actuator
- Size and type
- Stroke range
- Leakage
b) Control
valves having leakage class V and VII (TSO), leakage testing shall
be performed. A test ring must be fabricated
comprising a blind flange on the
valve outlet fitted with a 6mm bleed pipe and
a suitably rated isolation valve from
the center of the flange. The open end of the
bleed pipe shall be immersed
in a container of water so that the
discharge bubbles can be observed. The valve inlet shall be connected to a
source of pressure equal to the valve shut-off pressure. The specified signal
corresponding to the valve closed position under normal operating conditions
shall be applied to the valve actuator and if necessary adjustments made to the
valve until the leakage bubble rate is within the specified tolerance (Specify standard to be followed
per project spec).
6.10 Positioner (Stroke check)
a)
After checking the valve stroke without the
positioner shall be checked.
b)
Determine signal range and characteristic
curve through full stroke of the valve. Before calibration characteristic curve
shall be provided. Select proper travel character cam if provided.
c)
Connect power supply and/or air supply to
the positioner and actuator.
d)
Connect proper input signal source (4mA to
20mA or 24VDC) to the positioner.
e)
Adjust input signal so that the valve open
slowly, and stop when the valve is fully closed.
f)
Read the input signal and adjust zero
adjustment when error found. Repeat step e) and f) until valve corresponds with
closing signal within error limit.
g)
Adjust input signal so that the valve open
slowly, and stop when the valve fully opened.
h)
Read the input signal and adjust zero
adjustment when error found. Repeat step g) and h) until the valve corresponds
with closing and opening signal within error limit.
i)
Inject 0, 25, 50, 75 and 100% of its range
and read valve position with signal rising and falling. Action of the
positioner shall be checked (direct or reverse).
j)
Analyze the stroke characteristic curve and
figure out the reproducibility, which include dead band and hysteresis.
k)
If the character of the reproducibility are
not acceptable, check feed back cam style and / or mechanical condition of all
moving parts and correct deficiency if exist. Repeat step j) and k)
l)
Mechanical stops shall be checked as per
data sheet.
6.11 Valve
Action on Supply Failure
a) The action of the
valve on supply failure shall be checked with appropriate method.
b) If the control valve
is equipped with special accessories for the action of supply failure. The
functional check and / or calibration shall be executed.
c) Volume tank and lock
up valves operability will also be checked.
d) After the tests have
been completed, the instrument shall be identified with a colour sticker.
e) Test results /
readings will be filed and recorded on applicable calibration form.
6.12 Limit Switches / Proximity sensor
6.12.1
The function of the limit switches / Proximity sensor shall be checked
using a continuity test
set, for correctness
of setting and operation.
6.12.2
On motorized valves, care shall be taken to check the setting of
limit switches before putting power on the actuator and the actuator manually
placed at mid-travel prior to attempting to stroke the valve for the first
time. Reference manufacturer’s instructions.
6.12.3
After the tests have been completed, the instrument shall be
identified with a colour sticker.
6.12.3
Test results / readings will be filed and recorded on applicable
calibration form.
6.13 Solenoid Valves
6.13.1 Connect
an appropriate power supply via a switch.
6.13.2 Connect an air supply to the appropriate
port or ports.
6.13.3 Check the operation of the valve by
operating the switch and observing correct change over action.
6.13.4 Check the tightness of shut-off by
connecting a flexible tube to the outlet ports or port an immersing the free
end in the water to ensure that the valve closure is bubble-tight at the stated
design pressure.
6.13.5 Check where applicable, electrical &
manual reset, override and time delay features as called for on the valve
specification.
6.13.6 Check that the coil resistance is correct to
the specification.
6.13.7 After the test had been completed, the
instrument shall be identified with a colour sticker.
6.13.8 Test results / readings will be filed and
recorded on applicable calibration form.
6.14. Flow Elements
6.14.1 Flow elements e.g. orifice plates, vortex, etc.
shall not be installed until the flushing has been completed.
6.14.2 Flow elements such as vortex meters,
magnetic flow meters, etc., which are not usually tested in the field shall be
checked at the workshop or for
its manufacturer’s test certificate.
6.14.3 Before installation, the flow element should
be checked to ensure that the data and material specification stamped on the
data plate or tab handle is the same as the specification sheet.
6.14.4 Orifice plate should be examined for
flatness, bore siize and other dimensions against
Vendor appproved drawings and to ensure that they are undamaged. Do not
damage
orifice edge. The bore shall be checked with Vernier caliper. Flow
direction to be also verified prior to
on line installation.
6.14.5 Venturi system shall be checked against
specification for bore diameter, length and throat diameter.
6.14.6 Test
results / readings will be filed and recorded on applicable calibration form.
6.15 Analyzers (Conductivity meter/ PH meter)
Analyzers shall check
out by Vendor’s representative with the assistance of subcontractor
technicians based on vendor approved procedure or SAT where
applicable.
7 SAFETY
7.1.1 To ensure best practice HSE control is
being implemented throughout all Instrumentation work, Contractor Instrument
Supervisors and HSE Supervisor with Sub contractors Instrumentation Supervisors
and HSE Supervisor shall carry out inspections prior to Work commencing and at
regular intervals during the activities.
7.1.2
Persons working at height (above 1.8 meters)
shall be protected from falling by the installation of safe access/ egress and
working platforms.
7.1.3
Persons involved in Instrument calibration
work shall be provided with and use the necessary PPE and as a standard each
person shall wear a Safety Helmet and Safety footwear. The requirement for
additional PPE shall be identified in the Risk Assessment and may include the
use of the following:
7.1.4
Eye protection.
7.1.5
Hand
Protection.
7.1.6
Dust
masks.
7.1.7
Reflective
jackets if working in the vicinity of moving traffic.
7.1.8
Any
other necessary PPE
Note:
- The issue and use of PPE is the final step in protecting people and must not
be see as the only safety control method. Risks must be reduced to the smallest
amount possible and the PPE is the ‘back up’
equipment.
8 QUALITY
CONTROL
8.1 ITP is a document submitted to the
owner or owner’s representative formulated in an orderly manner by the
construction supervisor or site quality manager to record main working
processes for tests and quality inspections, and to enable the owner or owner’s
representative to assign inspection points.
8.2 Witness Point
8.2.1 Point where permission to the
next level is granted without Owner’s agreement.
8.3 Hold
Point
8.3.1 Point where further progress is not allowed
without Owner’s written permission
8.4
Inspector
8.4.1 Person that inspects whether processes
quality of materials or specifications are consistent with prescribed or
desired requisites.
