QATAR ENGINEERING & CONSTRUCTION COMPANY WLL (Qcon) Gate 69, Street 48, Salwa Industrial Area, Qatar Mailing Address; PO Box 24491, Doha, Qatar Tel: (+974) 458 7200, Fax: (+974) 458 7201 e-mail:
[email protected] web site: www.qcon.com..qa
Welding CALIBRATION PROCEDURE Document number
QCON-P&M-08
0
26-08-2014 Draft
Rev.
Date
Sudath Sanjeewa Description
ORIGINATED BY
CHECKED BY
APPROVED BY
IMPORTANT Hard copy of this document shall be considered uncontrolled unless signed and stamped as “Controlled Copy” by DCC with copy number and issue date. Current revision of this document is available in the Network Shared Folder. It is the responsibility of the user to verify that this copy is of the latest revision.
REVISION RECORD REV
DATE
DESCRIPTION
0
26-08-2014
Draft
INDEX SECTION
’
TITLE
PAGE
-
REVISION RECORD
2
-
INDEX
3
1.0
PURPOSE
4
2.0
SCOPE
4
3.0
DEFINITION
4
4.0
DIVERSION
4
5.0
RESPONSIBILITIES
4
6.0
CALIBRATION
5
7.0
REGISTRATION & CONTROL OF CALIBRATION
6
8.0
ACCEPTANCE CRITERIA
6
9.0
DOCUMENTS
6
1. PURPOSE 1.1. To established technical guidelines to perform and calibrate inverter welding machine, rectifier welding machine, A/C – transformer welding machine, an engine driven welding machine. And to ensure that only those calibrated welding machines will produce acceptable quality professional weld as per national and international standards. 1.2. To minimize the current and voltage deviations between welding machine set parameters and work piece and certify the welding machine. 1.3. Several national and international standards specify that the welding machine to be used for welding machine products shall be calibrated. 1.4. Welding machine current / voltage is an essential variable in all of the national and International Standards. A change in current / voltage can change weld joint properties and introduce unacceptable discontinuities. Hence having correct current / voltage reading on the welding machine is very vital to produce acceptable quality welds. 2. SCOPE This procedure details the requirement that is required to be implemented for the welding machine calibration. 3. EXPLANATION / DEFINITIONS Metrological comparison between a measurement device or an instrument with their respective benchmarks, certificates and their accuracy, in order to detect, report or eliminate by adjustment any inaccuracy of the instrument. 4. DIVERSION It is the difference in magnitude between the current rating of the welding machine and the actual value measured in amperage volt ammeter clamp, taking as basis the corresponding nominal value. 5. RESPONSIBILITIES 5.1. Production Supervisor and / or Sr. Foreman responsible for : 5.1.1.Use only calibrated welding machines. 5.1.2.Advice the staff involved and apply the requirements of this procedure 5.1.3.Arrange and meet with the minimum premises and equipment calibration. 5.1.4.Notify the Quality Control prior to the date for the calibration of welding machine. 5.2. The Section of the Quality / Welding Inspector responsible for 5.2.1.Notify the Technical Dept. prior to the date for the calibration of welding machine. 5.2.2.Receive the welding machine calibration certificates from Technical Dept. and inspect, the welding machine calibration certificate in acceptable criteria, 5.2.3.Calibration certificate to be stamped, sign and authorized to use the welding machine. 5.2.4.Verify the validity of the calibration time.(As per Client requirement) 5.2.5.Affix labels on the welding machine indicating the calibration. 5.2.6.Maintain proper inventory and calibration records.
5.3. The Section of the Technical / Electrical responsibility for: 5.3.1.Receive the notification for welding machine calibration. 5.3.2.Test the welding machine prior to calibration and certification. 5.3.3.Assigning competent technician to perform welding machine calibration. 5.3.4.Perform and calibrate the welding machine, utilizing calibrated master instrument.(Calibration standards traceable to Internal standards) 5.3.5.Adjust and minimise the parameter deviation. 5.3.6.Verify the validity of the calibration time.(As per Client requirement) 5.3.7.Issue welding machine calibration certificate. 5.3.8.Issue labels to stick on the welding machine indicating the calibration. 5.3.9.Maintain proper inventory and calibration records. 6. CALIBRATION 6.1. Calibration and certification of welding machine. 6.2. Technical staff required for welding machine calibration. 6.2.1. Welding inspector.(Witness) 6.2.2. An Electrician. 6.2.3. Qualified Welder 6.2.4. Document controller 6.3. Materials required for welding machine Calibration 6.3.1. Welding PPE. 6.3.2. Welding Consumable. 6.3.3. Steel plate appropriate. 6.3.4. Accessory. 6.3.5. Master instrument. (Third party Calibrated certify and valid ( traceable to internal standards) (properly protected from damage and
deterioration during handling, maintenance and storage) 6.3.6. 6.3.7. 6.3.8. 6.3.9.
Suitable and standard welding cables. Suitable and standard welding cable connectors. Suitable and standard welding earth clamp. Suitable and standard welding electrode holder
6.4. Frequency of Calibration. 6.4.1. All welding machine such as inverter welding machine, rectifier welding machine, A/C – transformer welding machine, an engine driven welding machine should be Calibrated and certify before use, and thereafter every six months. 6.4.2. All Master instruments should be Calibrated and certify before use, and thereafter every six months. Note: This period can be set by the contractor (CLIENT) but not higher than that specified above. 6.4.3. Welding machine Calibration Technique. 6.4.3.1. Welding Electrode cable clamp connect to the positive terminal of the welding machine to be test and calibrate. 6.4.3.2. Welding ground cable clamp connector to the negative terminal of the welding machine to be test and calibrate.
6.4.3.3. Energize the welding machine. ((ON)Electrically or (Start)Engine driven) 6.4.3.4. Test and record welding machine OCV (Open Circuit Voltage) and verify with the welding machine name plate. 6.4.3.5. Set the welding parameter positioning liver in the desired position. (Set point) 6.4.3.6. Engage with the volt – ammeter clamp the cable clamp electrode. 6.4.3.7. Carry out the reading of the clamp volt – ampere ammeter, comparing it with the values shown on the recorder panel of the welding machine.(Welding machine Dial) Note; Evidence records calibration results of deviations in from. Calibrations should happen in bands of every (It should indicate the calibration bands for gradual
measurement are taken e.g. every 40A, 60A, 80A Numbering is the same numbering allocated as indicated in the procedure ) 7. REGISTRATION AND CONTROL OF CALIBRATION. 7.1. The results of the calibration process must be registered in the Control of Calibration of welding machine. It should be kept track of time calibration, so no equipment is used with their deadlines expired. 7.2. The equipment may only be labelled when they are approved. 8. ACCEPTANCE CRITERIA The maximum permissible deviations for calibration are: + / - 20% on the Set point. Note: The maximum deviation is in accordance with the criteria established by Client. Porum not exceeding the amount fixed by the Standard. 9. DOCUMENTS 1. Master instrument Calibration Certificate. (Sample) 2. Electric Welding machine Calibration Certificate. (Sample] 3. Engine Driven Welding machine Calibration Certificate. (Sample) 4. Electrode oven Calibration Certificate. (Sample)
: Passed : Standard
EQUIPMENT STATUS
EQUIPMENT GRADE
P P Precision
Failed
P&M-031
DOWN
UP
50%
75%
:
:
:
:
:
:
:
:
:
100%
Tel. No. 458-7200, Fax. No. 460-1681
P.O. Box No. 24491, Doha, Qatar
P&M Department (Street 48, Gate 27)
CLIENT: …………………
SIGNATURE / DATE
± 2OC. ALL MEASUREMENT ARE TRACEABLE TO UK NATIONAL STANDARDS.
2. THIS IS TO CERTIFY THAT THE ABOVE EQUIPMENT HAS BEEN CALIBRATED 25%, 50%, 75% & 100% AND AMBIENT TEMP OF
CARRY NO IMPLICATION REGARDING THE LONG TERM STABILITY OF THE UNIT UNDER TEST.
QATAR ENGINEERING & CONSTRUCTION COMPANY WLL
NEXT CALIBRATION DUE ON
NEW SET READING
ERROR
AMPS AT CALIBRATION POINT
25%
RANGE
NEXT CALIBRATION DUE ON
DATE OF CALIBRATION
NBS CALIBRATION REF. NO.
QCON CONTROL NO.
INSTRUMENT SERIAL NO.
INSTRUMENT MODEL
INSTRUMENT GRADE / TYPE
INSTRUMENT MAKE
Volt / Amp
CALIBRATION STANDARD
DATE
1. THE RESULTS GIVEN IN THIS CERTIFICATE RELATE ONLY TO THE MEASURED VALUES OBTAINED AT THE TIME OF TEST AND
CALIBRATION CARRIED OUT BY (NAME)
REMARKS:
:
AMBIENT TEMPERATURE
SET POINT
: 70MMX50MTR
CABLE SIZE & LENGTH
110VAC
:
EQUIPMENT MODEL / SN.
Welding Volt
:
EQUIPMENT MAKE
Aux: 220VAC
:
EQUIPMENT CODE
EQUIPMENT OPERATING RANGE : Welding Amp
:
EQUIPMENT TYPE
BEING CALIBRATED
CALIBRATION CERTIFICATE FOR ELECTRIC WELDERS
: Welding Amp
EQUIPMENT OPERATING RANGE
DOWN
P&M-029
110VAC
220VAC
50%
75%
100%
25%
50%
75%
SELECTOR B NORMAL WELDING MEDIUM OCV
RANGE
NEXT CALIBRATION DUE ON
DATE OF CALIBRATION
NBS CALIBRATION REF. NO.
QCON CONTROL NO.
INSTRUMENT SERIAL NO.
INSTRUMENT MODEL
INSTRUMENT GRADE / TYPE
INSTRUMENT MAKE
100
:
:
:
:
:
:
:
:
:
Tel. No. 458-7200, Fax. No. 460-1681
CLIENT: …………………
SIGNATURE / DATE
± 2 O C. ALL MEASUREMENT ARE TRACEABLE TO UK NATIONAL STANDARDS.
2. THIS IS TO CERTIFY THAT THE ABOVE EQUIPMENT HAS BEEN CALIBRATED 50% & 100% AND AMBIENT TEMPERATURE OF
DATE
25%
50%
75
LARGE ELECTRODES HIGH OCV
Volt / Amp
CALIBRATION STANDARD
1. THE RESULTS GIVEN IN THIS CERTIFICATE RELATE ONLY TO THE MEASURED VALUES OBTAINED AT THE TIME OF TEST AND CARRY NO IMPLICATION REGARDING THE LONG TERM STABILITY OF THE UNIT UNDER TEST.
25%
Aux:
SELECTOR A OVERHEAD & VERTICAL LOW OCV
Precision
Failed
QATAR ENGINEERING & CONSTRUCTION COMPANY WLL P&M Department (Street 48, Gate 27) P.O. Box No. 24491, Doha, Qatar
NEXT CALIBRATION DUE ON
CALIBRATION CARRIED OUT BY (NAME)
REMARKS:
NEW SET READING
ERROR
POINT
CALIBRATION
AMP AT
SET POINT UP
: Standard
EQUIPMENT GRADE
:
: Passed
EQUIPMENT STATUS
AMBIENT TEMPERATURE
:
EQUIPMENT MODEL / SN.
:
:
EQUIPMENT MAKE
CABLE SIZE & LENGTH
:
EQUIPMENT CODE
Welding Volt
:
EQUIPMENT TYPE
BEING CALIBRATED
CALIBRATION CERTIFICATE FOR DIESEL WELDERS
100%
: : : Passed : Standard :
EQUIPMENT MAKE
EQUIPMENT MODEL / SN.
EQUIPMENT STATUS
EQUIPMENT GRADE
TEMPERATURE RANGE
P&M-032
:
RANGE
INITIAL DEVIATION
READING AFTER ADJUSTMENT
CARRY NO IMPLICATION REGARDING THE LONG TERM STABILITY OF THE UNIT UNDER TEST.
Tel. No. 458-7200, Fax. No. 460-1681
P.O. Box No. 24491, Doha, Qatar
P&M Department (Street 48, Gate 27)
CLIENT: …………………
SIGNATURE / DATE
± 2OC. ALL MEASUREMENT ARE TRACEABLE TO UK NATIONAL STANDARDS.
QATAR ENGINEERING & CONSTRUCTION COMPANY WLL
NEXT CALIBRATION DUE ON
: 12-Jan-15
NEXT CALIBRATION DUE ON
FINAL DEVIATION
READINGS OF INSTRUMENT BEING CALIBRATED
: 12-Jan-14
: 1E+05
: NOT SPECIFIED
: 40038287
DATE OF CALIBRATION
NBS CALIBRATION REF. NO.
QCON CONTROL NO.
INSTRUMENT SERIAL NO.
: 2000T
Volt / Amp
CHANGE DUE TO CALIBRATION
: DIGITAL THERMOMETER
: DIGITRON
THE RESULTS GIVEN IN THIS CERTIFICATE RELATE ONLY TO THE MEASURED VALUES OBTAINED AT THE TIME OF TEST AND
INITIAL READINGS
Precision
Failed
INSTRUMENT MODEL
INSTRUMENT GRADE / TYPE
INSTRUMENT MAKE
CALIBRATION STANDARD
2. THIS IS TO CERTIFY THAT THE ABOVE EQUIPMENT HAS BEEN CALIBRATED 25%, 50%, 75% & 100% AND AMBIENT TEMPERATURE OF
1.
CALIBRATION CARRIED OUT BY (NAME)
REMARKS:
STANDARD INSTRUMENT READINGS
:
EQUIPMENT CODE
DESIRED SET POINTS
:
EQUIPMENT TYPE
BEING CALIBRATED
