WPS

MEMBUAT WPS Ada pengalaman dengan temen di tempat kerja saya selama ini. Pertanyaannya mungkin sepeprti ni. Tanya :

Mas saya dapat tawaran kerja di tempat yang baru sebagai client, dengan tugas memverifikasi wps atau membuat wps …bagaimana sih caranya membuat WPS ? Saya nggak bisa mengerjakan pekerjaan seperti yang diminta tersebut di atas..Jadi terpaksa saya tolak job tersebut padahal gaji yang ditawarkan bisa 5x gaji saya saat ini.

Bahasan : Mungkin pertanyaan di atas banyak juga di alami oleh rekan rekan lain di tempat kerja saat ini. Sayang sekali kalau kita tidak dapat menguasai ilmu WPS ini. Di beberapa fabrikasi seperti Shipyard banyak para QC QA Engineer yang di suruh membuat WPS tanpa pengetahuan yang cukup. Sehingga secara qulitas dan standard WPS yang dibuat tidak memenuhi syarat min code standard tersebut. परह्न्य lagi para owner, surveyor, client yang memeriksa WPS tsb juga tidak mengerti bagaimana menilai WPS itu memenuhi standard। Jadilah WPS yang dibuat WPS ecek ecek … Bagaimana sih cara membuat WPS … (to be continue sect 2 )

weld defect

Weld Defect Trending

Pipeline welding – pipeline weld testing Designed for the pipeline weld testing industry, UT Scan delivers unprecedented reliability and accuracy. You can count on UT Scan in even the most demanding pipeline welding environments with its industrial grade computer hardware and precise manufacturing. Weld defects can be identified by : Type: planar or volumetric Location: through thickness depth Location: upstream weld side or downstream weld side Fusion defects with the parent metal, or weld interpass fusions defects Vertical height of defects Defect sizing within ± .5 – 1.0 mm Amplitude sizing and TOFD sizing UT Scan Plus Weld Software is programmable for job/criteria specifics, Automatic Defect Detection and Evaluation High/Low detection and measurement for Internal and External Quality Control/Defect Trending for Welding Foreman and Welding Engineers with all aspects of the defects known UT Scan's PlusWeld reporting software offers reporting and trending of defects and keeps a "live" record of the repair list. PlusWeld automatically collects and audits the weld testing results. It offers the operator and our clients and consultants a real-time view of the welding progress, defects and a defect trending, on an "as is", daily or project basis. The results are broken down by the welds, welder, defect types or a particular zone of the weld of interest. This will give you quality reporting information on your entire project in real time. UT Scan's Weld Defect Detection and Trending Detects planar defects more reliably than Gamma Ray or Manual UT can Defect trending reports are automatically generated by PlusWeld Reject able welds are documented and can be reported immediately following weld scan. Defects are identified in data file and file is stored. High P.O.D. for planar defects – No false alarm - No radiation - Faster results Defect height sizing – Depth measurements– ECA acceptance criteria can be used Fully cross-sectional view of defects with visualized high/low situations Scan Results Create one or more defects, cutouts, re-inspections or anomalies for each weld Includes: Defect type Start and end locations Weld pass Weld side Depths and Vertical Heights

Question Paper 8 1 Bs 499 part II communicates by the use of symbols the type of joint preparation to be used. Listed below are four symbols: which of these indicates the depth of penetration of the weld required on the joint. 2 Which of the following symbols would indicate that a weld has to be finished flush on the other side of the weld 3 what two factors in arc welding must be in equilibrium to enable a stable arc to be established A arc voltage B current C wire /electrode feed rate D metal burn off rate 4 in mma welding what parameter is used for the control of penetration into the base material A voltage B welding speed C iron powders in the coating D current 5 in the welding of a butt joint made from one side which of the following controls the profile of the root bead A root face B bevel angle C root gap D none of the above 6 what type of power source characteristic is required for manual welding A constant voltage B flat characteristic C drooping characteristic D motor generator 7 which one of the following destructive tests would indicate the toughness of weld parent metal – haz A macro B nick break C hardness D charpy v notch 8 degreasing components is essential for quality welding but some agents may A cause corrosion problems B gives off phosgene gas C leaves residuals D all of the above 9 which of the following chemical elements has the greater effect on the hardenability of steel plate Molybdenum B chromium C titanium D carbon 10 in mag / co2 welding which parameters give the greatest control of weld appearance during dip transfer or short circuit welding A wire stick out length B amperage C wire feed speed D inductance 11 in mma welding the slags produced can be varied to suit the welding position which type of slag would be required for welding in the hv position A fluid B viscous C none of the above D semi fluid 12 the weld metal deposit of mma electrodes achieves its mechanical strength through A the core wire B the flux coating C iron powders with the flux coating 13 what constituent is needed in a coating to prevent the formation of porosity when welding rimming steel A iron powders B calcium fluoride C silicon D calcium carbonate 14 welds made with high heat inputs show a reduction in one of the following properties A ductility B toughness C fatigue strength D mechanical strength 15 in the welding of austenitic pipe work the bore is usually purged with argon to A prevent the formation porosity in the weld B prevent burn through in the root run C prevent oxidation of the root bead D eliminate the formation of hydrogen 16 in x-ray work the quality of the image is assessed by the A density of the film B iqi indicator C kva available D stand off distance 17 a steel described as qt will have improved tensile properties because it has A had control of chemical composition B been heat treated C been quality tested D been vacuum melted 18 which one of the following type of steels would give rise to the formation of porosity when autogenously welded with an arc process A fully killed steel B semi killed steel C rimming steel D fine-grained steel 19 in submerged arc welding the use of excessively high voltage would result in A insufficient flux melting B excessive flux melting C slag removal difficulties D spatter 20 the use of cellulosic electrodes is often made when welding root pass of pipes in the field A hydrogen control is needed B iron powders in the elecrode C higher arc voltage can be obtained D shorter arc lrngth can be achieved 21 in the welding of austentic stainless steels the electrode and the plate material can be purchased with low carbon contents the reason for this is to prevent A cracking in the haz B the formation of chromium carbides C cracking in the weld material D distortion 22 submerged arc fluxes can be supplied in two forms these are A sintered and agitated B agitated and fsued C crushed and agglomerated D fused and agglomeraterd 23 in a steel which has improved creep properties at an elevated temperature whish one of the following elements helps in this improvement A tungsten B manganese C molybdenum D carbon 24 welding a steel plate of ceq of .45 would require preheating to A prevent formation of sulphides B prevent hardening in the haz C prevent formation for carbides D to improve mechanical properties of the weld 25 which one of the following process uses the keyholing system of fusion A FRICTION WELDING B diffusion bonding C electron beam welding D autogenous tig welding 26 in friction welding is the metal at the interface in the A liquid state B solid state C plastic state D elastic state 27 welding procedures may require weld to be deposited at a controlled rate of heat input high heat inputs would A have poor profile B have larger grain size C have high hardness in the haz D have low elongation properties 28 in a tensile test a brittle material would be indicated if the fracture surface A shows areduction in size B is flat and featureless C breaks in the weld metal D breaks in the parent metal 29 what destructive test would be required to ascertain the likelihood of cracking in the haz of a weld A nick break B side bend test C charpy impact D macro test 30 in submerged arc welding excessive arc voltage may cause A excessive penetration B change in weld metal properties C narrow weld width D excessive bead profile

सर्तिफिकाते एक्साम ई

Question Paper 8 1 Bs 499 part II communicates by the use of symbols the type of joint preparation to be used. Listed below are four symbols: which of these indicates the depth of penetration of the weld required on the joint. 2 Which of the following symbols would indicate that a weld has to be finished flush on the other side of the weld 3 what two factors in arc welding must be in equilibrium to enable a stable arc to be established A arc voltage B current C wire /electrode feed rate D metal burn off rate 4 in mma welding what parameter is used for the control of penetration into the base material A voltage B welding speed C iron powders in the coating D current 5 in the welding of a butt joint made from one side which of the following controls the profile of the root bead A root face B bevel angle C root gap D none of the above 6 what type of power source characteristic is required for manual welding A constant voltage B flat characteristic C drooping characteristic D motor generator 7 which one of the following destructive tests would indicate the toughness of weld parent metal – haz A macro B nick break C hardness D charpy v notch 8 degreasing components is essential for quality welding but some agents may A cause corrosion problems B gives off phosgene gas C leaves residuals D all of the above 9 which of the following chemical elements has the greater effect on the hardenability of steel plate Molybdenum B chromium C titanium D carbon 10 in mag / co2 welding which parameters give the greatest control of weld appearance during dip transfer or short circuit welding A wire stick out length B amperage C wire feed speed D inductance 11 in mma welding the slags produced can be varied to suit the welding position which type of slag would be required for welding in the hv position A fluid B viscous C none of the above D semi fluid 12 the weld metal deposit of mma electrodes achieves its mechanical strength through A the core wire B the flux coating C iron powders with the flux coating 13 what constituent is needed in a coating to prevent the formation of porosity when welding rimming steel A iron powders B calcium fluoride C silicon D calcium carbonate 14 welds made with high heat inputs show a reduction in one of the following properties A ductility B toughness C fatigue strength D mechanical strength 15 in the welding of austenitic pipe work the bore is usually purged with argon to A prevent the formation porosity in the weld B prevent burn through in the root run C prevent oxidation of the root bead D eliminate the formation of hydrogen 16 in x-ray work the quality of the image is assessed by the A density of the film B iqi indicator C kva available D stand off distance 17 a steel described as qt will have improved tensile properties because it has A had control of chemical composition B been heat treated C been quality tested D been vacuum melted 18 which one of the following type of steels would give rise to the formation of porosity when autogenously welded with an arc process A fully killed steel B semi killed steel C rimming steel D fine-grained steel 19 in submerged arc welding the use of excessively high voltage would result in A insufficient flux melting B excessive flux melting C slag removal difficulties D spatter 20 the use of cellulosic electrodes is often made when welding root pass of pipes in the field A hydrogen control is needed B iron powders in the elecrode C higher arc voltage can be obtained D shorter arc lrngth can be achieved 21 in the welding of austentic stainless steels the electrode and the plate material can be purchased with low carbon contents the reason for this is to prevent A cracking in the haz B the formation of chromium carbides C cracking in the weld material D distortion 22 submerged arc fluxes can be supplied in two forms these are A sintered and agitated B agitated and fsued C crushed and agglomerated D fused and agglomeraterd 23 in a steel which has improved creep properties at an elevated temperature whish one of the following elements helps in this improvement A tungsten B manganese C molybdenum D carbon 24 welding a steel plate of ceq of .45 would require preheating to A prevent formation of sulphides B prevent hardening in the haz C prevent formation for carbides D to improve mechanical properties of the weld 25 which one of the following process uses the keyholing system of fusion A FRICTION WELDING B diffusion bonding C electron beam welding D autogenous tig welding 26 in friction welding is the metal at the interface in the A liquid state B solid state C plastic state D elastic state 27 welding procedures may require weld to be deposited at a controlled rate of heat input high heat inputs would A have poor profile B have larger grain size C have high hardness in the haz D have low elongation properties 28 in a tensile test a brittle material would be indicated if the fracture surface A shows areduction in size B is flat and featureless C breaks in the weld metal D breaks in the parent metal 29 what destructive test would be required to ascertain the likelihood of cracking in the haz of a weld A nick break B side bend test C charpy impact D macro test 30 in submerged arc welding excessive arc voltage may cause A excessive penetration B change in weld metal properties C narrow weld width D excessive bead profile

CERTIFICATION EXAM 1

A. MULTIPLECHOICE 1. A crack type most associated with the submerged are werlding process is : Solidification cracking 2. An undersirable properly of alumminium oxide residue, when welding is that it : Requires more heat to melt in when compared to aluminium 3. A black triangular flag conjuction with a weld symbol as to EN 22553 Means: Welding to be carried out on site ( field weld ). 4. Austenetic stainless steel can be readly identified by: Lack of magnetic attraction. 5. A welding process where the welding plant control the travel speed and are gap, but under a constant supervision using a shielding gas mixture of 80 % argon – 20 % carbon dioxide is termed as : A mechanized MAG process. 6. A duty not normally intertaken by a welding Inspector is to : Measure residual stress 7. A crater crack my also be termed : Star crack 8. A welding inspectors main attributes include: a. Knowledge b. Honesty and integrity c. Good communicator All of the above 9. A code of practice for visual inspection should cover the following : Before, during and after welding 10. A steel described as QT will have improved tensile properties because it has ? Been heat - treated 11. A welding procedure is useful to : a. Give information to welder b. Give information to the inspector c. Gice “Confidence” to a product. All of the above 12. An essential variable may : a. change the properties of the weld b. influence the visual acceptability c. require Re – approved of a weld procedure All of the above 13. A Magnifying glass may be used during visual inspection but BS 5289 status that is magnetification should be : b. 2 – 2.5 14. A Planer defect is : a. Incomplete fusion defects b. Slag inclusion c. Incomplete penetration Both a & c 15. A “weave technique” may give rise to: a. Better profiles b. Improved toe blending c. Improved ripple shape All of the above 16. A Fatique failure is characteristic by the appearance of the fracture surface it would be: Smooth 17. A Code of practice is: A set of rules for manufacturing a specific product 18. A Metallurgical problem most associated with submerged are welding is: Solidification cracking in the weld metal 19. A Common gas/mixture used in MIG welding nickel alloy to combine good level of penetration with good arc stability would be: 100% Argon 20. A Large grain structure in steels is said to produce: Low fracture toughness values 21. A Welder qualification test is to Verify: The skill of the welder 22. A Fabricating procedure calls for fillet weld to be “blended in” by grinding. This is to influence: Fatigue Life 23. A carbon equivalent (CE) of 0.5% : Is high for carbon manganese steel and may require a preheat over 100% 24. Austenitic stainless are more susceptible to distortion when complete to feritic steel this is because : High coefficient, low termal conductivity. 25. Assuming that the welding process, material thickness, carbon equivalent and the welding parameters to be the same, which of the following joint type would normally required the highest preheat temperature. Tee joint (fillet weld) 26. Assuming that the applicable specification makes no mention of arc strikes, what would you expect to do as a welding inspector if arc strike were found on a component made of high tensile strenght material. Have the area checked for possible cracking 27. A multi pass MMA but weld made on carbon Steel Consist of 5 passes deposited using a 6 mm diameter electrode. A 12 pass weld made on the same joint deposited using a 4 mm diameter electrode on the same material will have : A lower heat input and higher degree of grain refinement 28. A balanced welding technique for example back step welding is most open used for : Reducing distortion 29. A tee joint an a support bracket is to be welded both side using a 5mm leg lenght fillet weld, each weld is to be intermittent 50 mm in total lenght, the gap between each weld is to be 25 mm. Which of the following is the correct symbol in accordance with ISO 2553 ? 5 50 (25) 5 50 (25) 30. A fatique cracks fracture surface (s) : Smooth

MENCARI EMAS HITAM

JACKET FABRICATION

MENGGALI TERUS SUMBER ENERGI

Dunia saat ini akan mengahadapi ancaman kekurangan energi dengan seiring meningkatnya kebutuhan dunia tanpa adanya penambahan cadangan energi alami yang tercipta hasil perubahan kimia jutaan tahun yang lalu.

Sumber informasi dunia mencatat kelangkaan energi tidak dapat dihindari dan akan menigkat efect nya pad 25 th mendatang. Dimana cadangan energi suda sangat tipis. isa idbaynagkan apabila dunia tanpa minyak/ gas?

Saat ini semua negara berlomba lomba mencari cadangan energi baru yang belum tergarap dengan harapan dapat memenuhi kebutuhannya sendiri dan sebagai sumber pendapatan negara denagan nilai yang sangat tinggi. Minyak, gas , batubara adalah primadona buat sumber keuangan negara.

SMAW WELDING PROSES

Stick or MSAW welding

Advantage Fabricated Metals performs a number of welding processes. The two most common welding processes we use include TIG, an acronym for Tungsten Inert Gas welding and MIG, an acronym for Metal Inert Gas welding. TIG is also referred to as GTAW (Gas Tungsten Arc Welding) and Heliarc®. MIG also is referred to as GMAW (Gas Metal Arc Welding). We also provide oxy-acetylene welding and stick or MSAW welding. Shielded Metal Arc Welding (SMAW) is frequently referred to as "stick" or "covered electrode" welding. Stick welding is among the most widely used welding processes. The flux covering the electrode melts during welding. This forms the gas and slag to shield the arc and molten weld pool. The slag must be chipped off the weld bead after welding. The flux also provides a method of adding scavengers, deoxidizers, and alloying elements to the weld metal. When an arc is struck between the metal rod (electrode) and the workpiece, both the rod and workpiece surface melt to form a weld pool. Simultaneous melting of the flux coating on the rod will form gas and slag which protects the weld pool from the surrounding atmosphere. The slag will solidify and cool and must be chipped off the weld bead once the weld run is complete (or before the next weld pass is deposited). The process allows only short lengths of weld to be produced before a new electrode needs to be inserted in the holder. Weld penetration is low and the quality of the weld deposit is highly dependent on the skill of the welder. Process characteristics of Shielded Metal Arc Welding (SMAW/Stick) SMAW welding: Uses a electrode rod that is quickly consumed, Uses equipment that is simple, inexpensive, and highly portable, Uses an electrode that provides and regulates its own flux, Provides all position flexibility, Is less sensitive to wind or drafts, Yields a weld with a variable quality and appearance based on operator skill, During the SMAW welding process the arc is established, the flux coating on the rod disintegrates and then forms a gas that shields the weld from the atmosphere. The slag that is produced by the flux coating prevents the weld metal from oxidizing.Equipment required to perform the SMAW welding process includes a constant current power source that supplies the power to the consumable rod electrode.The SMAW welding process typically is capable of producing three types of welded joints. They are: Butt joint Lap joint, and T-joint. The illustration below shows these three common welded joints.

RIG MAP ASEAN dan Kebutuhan ENERGI

Oil prices Dengan terus naiknya hargaminyak dunia yang selalu berfluktuasi telah membeikan dampak buruk bagi Indonesia dalam mengendalikan APBN dan pertumbuhana ekonomi secara makro. Indonesia mendapatkan tantangan baru untuk mencukupi kebutuhan akan sumber energi guna mengimbangi kebutuhan dalam negri. Pencarian sumber ladang minyak baru menjadi suatu alternatif yang mendesak untuk dilakukan oleh bangsa Indonesia. Sebebnarnya masih banyak ladang minyak Indonesia yang potensial yang mesti digarap secara intensif. Disamping mencarikan solusi alternatif dalam penghematan sumber energi itu sendiri

WELDING INSPECTOR DUTIES

THE DUTIES OF THE WELDING INSPECTOR VISUAL INSPECTION At any point in the course of welding, i.e. tacking, root pass, filler pass or capping pass, but particularly for the root and cap, a detailed inspection may be required. British Standard 5289: 1976 gives guidance on tools and responsibilities together with sketches of typical defects. The inspector at this point must - a) observe, identify and perhaps record (measure) the features of the weld. b) decide whether the weld is acceptable in terms of the particular levels that are permitted; defect levels may be ‘in-house’ or national codes of practice. When the defect size is in excess of the permitted level then either a concession must be applied for (from a competent person), or the weld rejected. INSPECTION BEFORE WELDING Before Assembly: Check * All applicable documents. * Quality plan is authorised and endorsed with signature, date and company stamp. * Application standard is up to date with the latest edition, revision or amendment. * The drawings are clear, the issue number is marked and the latest revision is used. * Welding procedure sheets (specifications) are available, have been approved and are employed in production. * Welder qualifications with identification and range of approval are verified and that only approved welders as required are employed in production. * Calibration certificates, material certificates (mill sheets) and consumer certificates are available and valid. * Parent material identification is verified against documentation and markings. * Material composition, type and condition. * Correct methods are applied for cutting and machining. * Identification of welding consumables such as electrodes, filler wire, fluxes, shielding and backing gases and any special requirements (e.g. drying) are met. * Plant and equipment are in a safe condition and adequate for the job. * Safety permits e.g. hot work permit, gas free permit, enclosed space certificate are available and valid. After Assembly Check * Dimensions, tolerances, preparation, fit-up and alignment are in accordance with the Approved drawings and standards. * Tack welds, bridging pieces, clamping and type of backing - if any used are correct. * Cleanliness of work area is maintained. * Preheat in accordance with procedure. NOTE Good inspection prior to welding can eliminate conditions that lead to the formation of defects. INSPECTION DURING WELDING Check * The welding process must be monitored. * Preheat and interpass temperatures must be monitored. * Interpass cleaning - chipping, grinding, gouging, must be monitored. * Root and subsequent run sequence. * Essential variables such as current, voltage, travel speed to be monitored. * Filler metals, fluxes and shielding gases are correct. * Welding is in compliance with weld procedure sheet and application standard. INSPECTION AFTER WELDING Check * Visual inspection to be carried out to ascertain acceptability of appearance of welds. * Dimensional accuracy to be ascertained. * Conformity with drawings and standards requirements. * Post weld heat treatment, if any, monitored and recorded. * NDT carried out and reports assessed. * Assess defects as to either repairing, or application for concession. * Carry out any necessary repairs. * Control of distortion REPAIRS * Repair procedure and welding code should be authorised. * Defect area should be marked positively and clearly. * Check when partially removed and fully removed (visual and NDT). * Re-welding should be monitored. * Re-inspect completed repair. Collate all documents and reports. Pass the document package on to a higher authority for final inspection, approval and storage.

WPS BASED ON ASME IX

RINGKASAN ASME IX

ARTICLE II WELDING PROCEDURE QUALIFICATION QW200.1 1. Change o the WPS : Change maybe made in non essential variables of WPS without re qualification 2. Change in essential or supplementary essential require re qualification. 3. Available of the WPS.A WPS used for production welding shall be available for reference and reviewed by Authorized Inspector. QW-200.2 1. PQR is the record of the welding data used to weld a test coupon, also contain test result of the test specimen. 2. Contents of PQR ; all essential variable, when require supplementary essential variable during the welding of the test coupon. 3. Change of PQR ; not permitted except : editorial correction, or addenda. Example correction of F Number, A number, P number hat was assigned to a particular. For example also, section IX may assign a new F number to a filler metal or adopt a new filler metal under an establish F Number. 4. All change in PQR req recertification by manufacturer or contractor. 5. Availability PQR : PQR used to support QPS shall be available for reviewed by AI 6. Multi WPSs with one PQR/ Multi PQRs with one WPS. QW-200-3 1. To reduce number of WPSs P number assigned to base metal dependent on characteristic such as : composition, mechanical properties, weldability. 2. In general, Notch toughness req are mandatory for all P no 11 quenched and tempered metals. QW-200.4 Combination of Welding Procedures 1. More than WPS having different essential, supplementary essential, or non essential variable may be used in a single production joint. 2. Where more than one WPS specifying different process, filler metals, or others essential or supplementary essential variables used in one joint QW 451 shall be used to determine the range of base metal thickness and max weld metal thickness qualified. 3. For GTAW, SMAW, GMAW, PAW, and SAW, a combination of these process, a PQR for a process recording a test coupon that was at least ½ in (13mm) thick may be combined with one o or more other PQRs recording another welding process and any greater base metal thickness. In this case the process recorded on the first PQR may be used to deposit the root layers using the process recorded on that PQR up to 2t. QW-201 Manufacturer’s or Contractor’s Responsibility 1. Each manufacturer or contractor shall qualified the WPS by the welding of test coupons and the testing of specimen, and the recording if welding data and test result in a document known as PQR 2. When a manufacturer or contractor or part of manufacturer or contractor is acquired by a new owner, the PQRs and WPSs may be used by new owner without re qualification, provided all of the following are met : a. The new owner take responsible for the WPS and PQR b. The WPS reflect the name of the new owners c. The QC system/QA program reflects the source of the PQRs as being from the former manufacturer or contractor QW-202 Type of Test Required QW-202.1 Mechanical Test 1. The type and number of test specimen that shall be test to qualified groove are given in QW 451 and shall be removed in a manner similar to that shown in QW-463. 2. If any test specimen required by W 451 fails to meet the applicable acceptance criteria, the test coupon shall be considered as failed. 3. When it can be determined that the cause of failure is not related to welding parameter, another test coupon may be welded using identical welding parameter. 4. Alternatively, if adequate material of the original test coupon exists, additional test specimen may be removed as closed as practicable to original specimen location 5. When it has been determined that the test failure was caused by an essential or supplementary essential variable, a new test coupon may be welded with appropriated changes to the variables that was determined to cause the test failure. QW-202.2 Groove and Fillet Welds Qualification for groove full penetration welds ; limit qualification QW 451. Qualification for partial Penetration Groove Welds ; as req QW 451. Qualification for Fillet Welds ; WPS qualification for fillet welds may be made on groove weld test coupon using test specimen in QW-202.2a or b. Fillet weld procedures so qualified may be used for welding all thickness of base metal for all size of fillet welds, and all diameter of pipe or tube accordance with QW451.4 QW-202.3 Weld Repair and Buildup. WPS qualified on groove welds shall be applicable for weld repairs to groove and fillet welds and for weld buildup under the following provision : There is no limitation on the thickness of base metal or deposited weld metal for fillet weld. For other than fillet welds, the thickness range for base metal and deposit weld metal for each welding process shall be in accordance with QW 451, except there need be no upper limit on the base metal thickness provided qualification was made on base metal having thickness of 1 ½ in (38 mm) or more. QW-202.4 Dissimilar Base Metal Thickness WPA qualified on groove welds shall be applicable for production welds between dissimilar base metal thickness provided ; The thickness of the thinner shall be within the range permitted by QW 451 The thickness of the thicker member shall be as follows : For P-No.8, P No-41, P No-42, P No-43, P No-44, P No-45, P No-46, P No-49, P No-51, P No-52, P No-53, P No-61, P No-62 metal there shall be no limitation on the max thickness of the thicker production member in joints of similar P-number materials provided qualification was made on base metal haing thickness of ¼ in (6mm) or greater. for all other metal the thickness of the thicker member shall be within the range permitted by QW 451 except there need be no limitation on the max thickness of thicker production member provided qualification ws made on base metal having a thickness of 1 ½ in (38 mm) or more.

RINGKASAN ASME IX ARTICLE II WELDING PROCEDURE QUALIFICATION QW200.1 1. Change o the WPS : Change maybe made in non essential variables of WPS without re qualification 2. Change in essential or supplementary essential require re qualification. 3. Available of the WPS.A WPS used for production welding shall be available for reference and reviewed by Authorized Inspector. QW-200.2 1. PQR is the record of the welding data used to weld a test coupon, also contain test result of the test specimen. 2. Contents of PQR ; all essential variable, when require supplementary essential variable during the welding of the test coupon. 3. Change of PQR ; not permitted except : editorial correction, or addenda. Example correction of F Number, A number, P number hat was assigned to a particular. For example also, section IX may assign a new F number to a filler metal or adopt a new filler metal under an establish F Number. 4. All change in PQR req recertification by manufacturer or contractor. 5. Availability PQR : PQR used to support QPS shall be available for reviewed by AI 6. Multi WPSs with one PQR/ Multi PQRs with one WPS. QW-200-3 1. To reduce number of WPSs P number assigned to base metal dependent on characteristic such as : composition, mechanical properties, weldability. 2. In general, Notch toughness req are mandatory for all P no 11 quenched and tempered metals. QW-200.4 Combination of Welding Procedures 1. More than WPS having different essential, supplementary essential, or non essential variable may be used in a single production joint. 2. Where more than one WPS specifying different process, filler metals, or others essential or supplementary essential variables used in one joint QW 451 shall be used to determine the range of base metal thickness and max weld metal thickness qualified. 3. For GTAW, SMAW, GMAW, PAW, and SAW, a combination of these process, a PQR for a process recording a test coupon that was at least ½ in (13mm) thick may be combined with one o or more other PQRs recording another welding process and any greater base metal thickness. In this case the process recorded on the first PQR may be used to deposit the root layers using the process recorded on that PQR up to 2t. QW-201 Manufacturer’s or Contractor’s Responsibility 1. Each manufacturer or contractor shall qualified the WPS by the welding of test coupons and the testing of specimen, and the recording if welding data and test result in a document known as PQR 2. When a manufacturer or contractor or part of manufacturer or contractor is acquired by a new owner, the PQRs and WPSs may be used by new owner without re qualification, provided all of the following are met : a. The new owner take responsible for the WPS and PQR b. The WPS reflect the name of the new owners c. The QC system/QA program reflects the source of the PQRs as being from the former manufacturer or contractor QW-202 Type of Test Required QW-202.1 Mechanical Test 1. The type and number of test specimen that shall be test to qualified groove are given in QW 451 and shall be removed in a manner similar to that shown in QW-463. 2. If any test specimen required by W 451 fails to meet the applicable acceptance criteria, the test coupon shall be considered as failed. 3. When it can be determined that the cause of failure is not related to welding parameter, another test coupon may be welded using identical welding parameter. 4. Alternatively, if adequate material of the original test coupon exists, additional test specimen may be removed as closed as practicable to original specimen location 5. When it has been determined that the test failure was caused by an essential or supplementary essential variable, a new test coupon may be welded with appropriated changes to the variables that was determined to cause the test failure. QW-202.2 Groove and Fillet Welds Qualification for groove full penetration welds ; limit qualification QW 451. Qualification for partial Penetration Groove Welds ; as req QW 451. Qualification for Fillet Welds ; WPS qualification for fillet welds may be made on groove weld test coupon using test specimen in QW-202.2a or b. Fillet weld procedures so qualified may be used for welding all thickness of base metal for all size of fillet welds, and all diameter of pipe or tube accordance with QW451.4 QW-202.3 Weld Repair and Buildup. WPS qualified on groove welds shall be applicable for weld repairs to groove and fillet welds and for weld buildup under the following provision : There is no limitation on the thickness of base metal or deposited weld metal for fillet weld. For other than fillet welds, the thickness range for base metal and deposit weld metal for each welding process shall be in accordance with QW 451, except there need be no upper limit on the base metal thickness provided qualification was made on base metal having thickness of 1 ½ in (38 mm) or more. QW-202.4 Dissimilar Base Metal Thickness WPA qualified on groove welds shall be applicable for production welds between dissimilar base metal thickness provided ; The thickness of the thinner shall be within the range permitted by QW 451 The thickness of the thicker member shall be as follows : For P-No.8, P No-41, P No-42, P No-43, P No-44, P No-45, P No-46, P No-49, P No-51, P No-52, P No-53, P No-61, P No-62 metal there shall be no limitation on the max thickness of the thicker production member in joints of similar P-number materials provided qualification was made on base metal haing thickness of ¼ in (6mm) or greater. for all other metal the thickness of the thicker member shall be within the range permitted by QW 451 except there need be no limitation on the max thickness of thicker production member provided qualification ws made on base metal having a thickness of 1 ½ in (38 mm) or more.

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PREHEAT WELDING

The purpose of preheat:- 1. Reduce the risk of hydrogen cracking 2. Reduce the hardness of the weld heat affected zone 3. Reduce shrinkage stresses during cooling and improve the distribution of residual stresses. If preheat is locally applied it must extend to at least 75mm from the weld location and be preferably measured on the opposite face to the one being welded. Got To The Pre-Heat Calculator Background To Preheating When hydrogen diffusing from a solidified weld meets a hard microstructure under a tensile stress a crack is likely! Hydrogen cracking normally occurs in the heat affected zone where hard microstructure is to be found, occasionally it can occur in weld metal. HydrogenThis is a very searching gas that can be liberated by oil, grease, rust etc. and water under the right conditions. The greatest risk comes from hydrogen generated within the arc from damp or contaminated welding consumables, mainly fluxes or electrode coatings. Contamination on the parent metal can also be a risk unless the heat from the welding arc can drive it away. Moisture from condensation on the parent metal will normally be driven off by the heat from the arc before it can get into the weld pool. Hydrogen in the atmosphere is unlikely to penetrate the arc envelope unless welding is carried out in very damp and humid conditions. A hydrogen crack can take anything from a few hours to 24 hours to occur. After 24 hours cracking is still possible but less likely, although there have been some reported cases of cracking at 72 hours. It is therefore good practice to allow at least 48 hours before carrying out any NDE. Hydrogen will eventually disperse from the parent metal, within a few days at room temperature or a few hours if held at around 200°C. Hydrogen cracking is only possible at room temperature, this is why it is also referred to as cold cracking Parent MetalA hydrogen crack requires a hard microstructure which is created by a hardenable material subject to fast cooling from 800°C to 500°C. Cooling can be slowed down by:- applying preheat, maintaining a high interpass temperature, increasing welding power and reducing travel speed. The heat sink caused by the parent metal thickness and the number of available paths the heat can take to escape, also influence cooling rate. (However once the heat sink reaches a certain size further increases have a negligible effect on cooling rate.). This is why when determining preheat the term combined thickness is used, for a butt weld it is twice the thickness of the parent material and for a T fillet weld three times the thickness. The hardening of a carbon manganese steel/low alloy steel is influenced primarily by carbon content and to a lesser extent other constituents such as manganese, chrome, silicone etc. The Carbon Equivalent is a formula used to express the harden-ability of a particular alloy steel in terms of an equivalent plain carbon steel. Several such formula exist, the one favoured for low alloy steel is the IIW formula: CEIIW = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15 Current steel specification do not restrict or limit the Carbon Equivalent and as most steel specs permit a wide range of composition it is possible that one batch of steel may require pre-heat and another may not. Very low sulphur ( <>

Heat Treatment

1 INTRODUCTION Various codes and specifications require that welded structures such as pressure vessels and offshore platforms be post weld heat treated (PWHT), depending on the type and thickness of the welded joint. Post weld heat treatment reduces the effect of any stresses induced by the welding process and tempers the heat-affected zone. The PWHT may be performed several times on a structure during fabrication and after weld repairs, resulting in an accumulation of the total time at soaking temperature. In some instances, the original welds of the structure or vessel may be subjected to cumulative PWRT cycles which exceed the amount of time qualified for by the original welding procedure qualification tests. Because PWHT, in some instances, may result in the loss of both the heat-affected zone and weld metal strength and toughness,1 the mechanical properties of the weld-joint may deteriorate, as the vessel is repaired repeatedly. This may be undesirable, since it is not known whether the mechanical properties of a weldment are still acceptable. Studies1,2 have been conducted to study the effect of a long PWHT on the properties of constructional and pressure vessel steel weldments. Post weld heat treatment may have a beneficial, detrimental or negligible effect on the properties (especially toughness) of the weidments, depending on the chemical composition of the steel, welding procedure used and PWHT time and temperature. The purpose of the current study is to provide detailed information on the effect of a long PWHT on the microstructure and mechanical properties of a welded joint in ASTM A302 Gr B pressure vessel steel. Weld-joints of the steel in the as-welded and post weld heat treated conditions were studied. The mechanical properties of the weldments were determined by heat-affected zone (HAZ) and weld metal Charpy impact and hardness tests, HAZ fracture toughness tests and transverse weld tensile tests. Tests on the HAZ were supplemented by Charpy impact and hardness tests on HAZs generated from thermal simulation techniques. Metallographical examination included optical and transmission electron microscopy. 2 EXPERIMENTAL PROCEDURE 2.1 Materials and welding procedure Normalized ASTM A302 Gr B plate material from manufacturers A and B, with dimensions of approximately 500 x 500 x 30 mm was used. The test steels had a ferrite-pearlite/bainite microstructure. Welds were deposited using the submerged-arc welding (SAW) process; the materials used were a commercial SD3-Mo wire (3.2 mm dia.) in combination with an OERLIKON OPl2lTT basic welding flux. The chemical compositions of the base metal and weld metal