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Common question welding storage API 650 (part 2)
Question: Is the conversion of design wind velocity of 100 mph to a peak 3 second wind gust 50 m/s giving design wind pressure of 31 psf or 1.485 kPa correct?
Answer: The American Petroleum Institute does not approve, recommend, or endorse any proprietary or specific design; nor does it limit the method of design or form of construction that might be used to conform to an API Standard. Therefore, we cannot act on your inquiry. We suggest that you review the notes to Sections 3.9.6.1 and 3.9.7.1.
Question: Reference API 650 Section 3.9.6.1, is it permissible to use a double wind girder in lieu of a top wind girder on an open top tank?
Answer: The top wind girder must meet the requirements of API 650 Section 3.9.6. API does not restrict the details of construction.
Question: Must corrosion allowance be subtracted from t in the formula of 3.9.7.1 and 3.9.7.2?
Answer: No
Question: Does API 650 require the tank supplier to meet the intermediate wind girder requirements of Section 3.9.7 for all fixed roof tanks?
Answer: Yes
Question: If more than one intermediate wind girder is required, is the section modulus of the second intermediate wind girder based on the height between the second intermediate wind girder and the top wind girder, or should H1 be based on 1/2 the distance between adjacent wind girders/stiffeners where the bottom plate counts as the bottom stiffener?
Answer: To determine the section modulus of the second intermediate wind girder, first determine the transformed shell height equal to the distance between the fist wind girder and the top wind girder. Subtract this value from the total transformed shell height determined in Section 3.9.7.2. The remaining shell is then transposed to an actual shell height and this value is used for H1 in the formula in Section 3.9.7.6.
Question: In Section 3.9.7.1, should footnote (a) be referred to when analyzing wind velocities other than 100 mph?
Answer: Yes
Question: Does Section 3.9.6 apply only to open top tanks and Appendix G tanks?
Answer: Yes
Question: Is it correct to consider length of shell 1.47×(D×t)0.5 specified in 3.9.7.6.2 on each side of the shell-ring attachment, resulting a total shell length of [2×1.47×(D×t)0.5 + (width of wind girder in contact with shell)]?
Answer: Yes
Question: If the corrosion allowance plus the calculated thickness is less than 3/16 in. thick, must the corrosion allowance be added to the 3/16 in. minimum nominal roof thickness?
Answer: No
Question : Does a 2% slope for a supported cone roof tank meet the requirements of API 650?
Answer : No
Question : When designing a cone roof based on the formulas in API 650, are factors of safety included in the rules of API 650 or must they be considered separately by the tank designer?
Answer : The necessary and appropriate factors of safety are included inherently in the design rules of API 650.
Question : Is welding of the main roof support members to the roof plates allowed by the standard?
Answer : No, see API 650, Section 3.10.2.3, that states that roof plates of supported cone roofs shall not be attached to the supporting members.
Question : How do you size an emergency vent for a sulfuric acid storage tank?
Answer : API can only provide interpretations of its standard and consider revisions based on new data or technology. API does not act as a consultant on specific engineering problems or on the general understanding or application of the standard.
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AWSD1.1
Visual Inspection Acceptance Criteria All welds shall be visually inspected and shall be acceptable if the criteria of Table 6.1 AWS D1.1 are satisfied. To more explanation about Visual Inspection Acceptance Criteria you can open AWS D1.1 section 6 (inspection) part C.
Before you inspect and make decision about weld as per AWS D1.1, you must know definitions of:
1. Statically Loaded Nontubular Connections (more detail see Section 2 part B AWS D1.1)
2. Cyclically Loaded Nontubular Connections (more detail see Section 2 part B,C AWS D1.1)
3. Tubular Connection (all Load) (more detail see Section 2 part D AWS D1.1)
Below Summary Visual Inspection Acceptance Criteria As per AWSD1.1 Table 6.1 :
- Any Crack shall be unacceptable, regardless of size or location
- No Lack of fusion
- All craters crack (start/end) shall be filled, except for the end of intermittent fillet weld outside of their effective length
- All weld profiles shall be free from cracks, overlaps, and the unacceptable profile discontinuities exhibited in Figure 5.4.
- Visual inspection of welds in all steels may begin immediately after the completed welds have cooled to ambient temperature. Acceptance criteria for ASTM A 514, A 517, and A 709 Grade 100 and 100 W steels shall be based on visual inspection performed not less than 48 hours after completion of the weld.
- The size of a fillet weld in any continuous weld may be less than the specified nominalsize (L) without correction by the following amounts (U) on Table 6.1 - Undercut and porosity see more detail on Table 6.1
Methods of Testing and Acceptance Criteria for WPS Qualification (Section 4) Visual Inspection.
For acceptable qualification, welds shall meet the following requirements:
(1) The weld shall be free of cracks.
(2) All craters shall be filled to the full cross section of the weld.
(3) The face of the weld shall be flush with the surface of the base metal, and the weld shall merge smoothly with the base metal. Undercut shall not exceed 1/32 in. [1 mm]. Weld reinforcement shall not exceed 1/8 in. [3 mm].
(4) The root of the weld shall be inspected, and there shall be no evidence of cracks, incomplete fusion, or inadequate joint penetration. A concave root surface is allowed within the limits shown below, provided the total weld thickness is equal to or greater than that of the base metal.
(a) The maximum root surface concavity shall be 1/16 in. [2 mm] and the maximum melt-through shall be 1/8 in. [3 mm].
(b) For tubular T-, Y-, and K-connections, melt-through at the root is considered desirable and shall not be cause for rejection.
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AWSD1.1
RT Acceptance Criteria Welds that are subject to RT in addition to visual inspection shall have no cracks and shall be unacceptable if the RT shows any discontinuities exceeding the following limitations (E = weld size).
2. To see detail RT Acceptance Criteria for Cyclically Loaded Nontubular Connections you can open Section 6.12.2 AWS D1.1 and Figure 6.4 . Limitations.
The limitations given by Figures 6.4 and 6.5 for 1-1/2 in. [38 mm] weld size shall apply to all weld sizes greater than 1-1/2 in. [38 mm] thickness.
3. To see detail RT Acceptance Criteria for Tubular Connections you can open Section 6.12.3 AWS D1.1 and Figure 6.6
(CMIIW)
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API 1104 : RT and Visual Inspection Acceptance Criteria
API 1104 Section 9 acceptance standards presented apply to imperfections located by radiographic, magnetic particle, liquid penetrant, and ultrasonic test methods and also be applied to visual inspection. Nondestructive testing shall not be used to select welds that are subjected to destructive testing.
Below Visual Inspection Acceptance Criteria as per API 1104 :
# The crack, of any size or location in the weld, is not a shallow crater crack or star crack shall be rejected. The crack is a shallow crater crack or star crack with a length that exceeds 5/32 in. (4 mm) also rejected.
# Undercutting adjacent to the cover or root bead shall not exceed the dimensions given in Table 4(Maximum Dimension of Undercutting) and Section 9.3.11
# Inadequate Penetration (detail see Section 9.3.1 , 9.3.2, 9.3.3 and figure 13) can’t exceed 1 inch.
# Incomplete Fusion shall be considered a defect should any of the following conditions exist:
a. The length of an individual indication of IF exceeds 1 in.(25 mm).
b. The aggregate length of indications of IF in any continuous 12-in. (300 mm) length of weld exceeds 1 in. (25 mm).
c. The aggregate length of indications of IF exceeds 8% of the weld length in any weld less than 12 in. (300 mm) in length.
And fore more Incomplete Fusion can see on Section 9.3.5 (figure 17)
# Internal Concavity (Any length of internal concavity is acceptable, provided the density of the radiographic image of the internal concavity does not exceed that of the thinnest adjacent parent material. For areas that exceed the density of
the thinnest adjacent parent material, the criteria for burn-through (see 9.3.7) are applicable) more detailed see Figure 18.
# Burn-Through (The maximum dimension exceeds 1/4 in. (6 mm) and the density of the BT’s image exceeds that of the thinnest adjacent parent material) more detailed see Section 9.3.7.1, 9.3.7.2, 9.3.7.3 .
# Slag Inclusions (when the size of a radiographic indication of slag is measured, the indication’s maximum dimension shall be considered its length) more detailed see Section 9.3.8.1, 9.3.8.2, 9.3.8.3)
# Porosity (The size of an individual pore exceeds 1/8 in. (3 mm)) more detailed conditions see Section 9.3.9.2 until 9.3.9.4 and Figure 19 or 20.
# Excluding incomplete penetration due to high-low and undercutting, any accumulation of imperfections (AI) shall be
considered a defect should any of the following conditions exist:
a. The aggregate length of indications in any continuous 12-in. (300-mm) length of weld exceeds 2 in. (50 mm).
b. The aggregate length of indications exceeds 8% of the weld length.
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Welding Inspector Reference Literature
Good Welding inspector should familiar with many Welding Reference Literature like Standard/Code/Rules, Client specs, Quality control procedure and etc.
There are some Reference Literature to support welding inspector jobs:
AWS D1.1/D1.1M - 2008 = Structural welding code - Steel
AWS A2.4 – 2007 =Standard symbols for welding, brazing and non-destructive examination
AWS D1.2M - 2008= Structural Welding Code - Aluminium
AWS A5.3/A5.3M – 1999 (R2007)= Specification for aluminium and aluminium alloy electrodes for shielded metal arc welding
AWS D10.7M/D10.7 - 2008 = Guide for the gas shielded arc welding of aluminium and aluminium alloy pipe
AWS A5.10/A4.10M-1999 (R2007)= Specification for Bare Aluminium and Aluminium Alloy Welding Electrodes and Rods
ASME PV Code 8 Div 1:2008 = Boiler and pressure vessel code – pressure vessels
ASME and PV Code 2B:2008= Boiler and pressure vessel code – materials – Non-ferrous material specifications
Welding Reference Literature from British Standards:
BS EN 22553:1995= Welded, Brazed and Soldered joints - Symbolic Representation on Drawings
BS EN 13622:2002= Gas Welding Equipment – Terminology – Terms used for gas welding
equipment
BS EN 970: 1997 =Non-destructive Examination of Fusion Welds – Visual Examination
BS EN 1011:2009= Welding – Recommendations for Welding of Metallic Materials.
Part 1: General Guidance for Arc Welding
Part 2: Arc Welding of Ferritic Steels
BS EN ISO 15607:2003= Specification and Qualification of Welding Procedures for Metallic Materials – General rules
BS EN 287-1:2004 = Qualification Test of Welders - Fusion Welding, Part 1: Steels.
BS EN ISO 15614-1:2004= Specification and Qualification of Welding Procedures for Metallic Materials – Welding Procedure Test. Part 1 – Arc and Gas Welding of Steels and Arc Welding of Nickel and Nickel alloys
BS EN 1011-4:2000 =Welding – Recommendations for Welding of Metallic Materials. Arc welding of aluminium and aluminium alloys
BS EN 1435: = Non-destructive examination of welds: radiographic examination of
welded joints
BS EN 757:1997= Welding Consumables – Covered Electrodes for Manual Metal Arc Welding
of High Strength Steels – Classification
BS EN ISO 636:2008= Welding Consumables – Rods, wires and deposits for Tungsten Inert Gas welding of non alloy and fine grain steels – classification
BS EN ISO 9606-2:2004= Qualification test of welders. Fusion welding. Aluminium and aluminium alloys
BS EN ISO 17632:2008= Welding Consumables – Tubular cored electrodes for gas shielded and nongas shielded metal arc welding of non-alloy and fine grant steels.Classification.
BS EN 910:1996= Destructive Tests on Welds in Metallic Materials- Bend Tests
BS EN 895:1995:= Destructive Tests on Welds in Metallic Materials – Transverse Tensile Test
BS EN 1321:1997= Destructive Tests on Welds in Metallic Materials – Macroscopic and
Microscopic Examination of Welds
Welding Reference Literature from ISO Standards:
ISO 17636:2003= Non-destructive Testing of Welds – Radiographic Testing of Fusion
Welded Joints
ISO 19232:2004= Non-destructive testing: Image quality of radiographs, Parts 1 – 5
REFERENCE LITERATURE RELEVANT TO RADIOGRAPHIC INTERPRETATION
BS EN ISO 2560:2005= Welding consumables. Covered electrodes for manual metal arc welding of non-alloy and fine grain steels. Classification.
BS EN ISO 5817:2003= Welding – Fusion Welded Joints in Steel Nickel Titanium and their alloys(Beam Welding excluded). Quality levels for imperfections.
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TWI training - European Welding Standards Course
TWI training - European Welding Standards Course Objectives:
TWI training - European Welding Standards Course student able to qualify welding procedures and/or welders TWI training - European Welding Standards Course give students the required knowledge to allow them to write WPS
Understanding how to use the latest European Standards/British Standards for Welding Procedure Qualification (BS EN ISO 15607, 15614 Parts 1 & 2, 15609) and Welder Qualification (British Standards/BS EN ISO 287 Parts 1 & 2).
image source: www.aacc.edu
A thorough examination of the relevant welding standards, together with class exercises, will give attendees a sound welding knowledge of how welding procedures and welders/operator can be qualified, how to conduct welding procedure qualification tests, what documentation is required for the qualification records,testing of qualification welds, how to write qualified Welding Procedure Specification for production welding, how essential variables influence test requirements and production welding.
TWI training - European Welding Standards Course Suitable for:
Welding co-ordinators (British Standards/BS EN 719) and other welding specialists involved in the qualification of welding procedures specification, and/or welders and welding operators qualification.
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TWI training - ASME(American Society of Mechanical Engineering) IX Welding Standards Course
TWI training - ASME(American Society of Mechanical Engineering) IX Welding Standards Course Objectives:
TWI training - ASME IX Welding Standards Course student able to understand detailed requirements of approval tests
TWI training - ASME IX Welding Standards Course student able to have the knowledge to supervise welder and weld procedure approval tests
TWI training - ASME IX Welding Standards Course student able to organise and supervise the necessary laboratory tests
TWI training - ASME IX Welding Standards Course student able to interpret test results and identify where reapproval is necessary
TWI training - ASME IX Welding Standards Course student able to understand how to complete the required documentation
image source: www.aacc.edu
Inspectors, Engineers, supervisors responsible for approval testing.
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Significant changes in AWS D1.1 2010 Edition
The AWS/American Welding Society is a welding professional organization that trains and certifies welding professionals. If you are looking to get good career and high salary like welding professional, you should get the American Welding Society/AWS D1.1 certification before that. In order to get AWS D1.1 certification, you must pass a written and a practical test to show a welding instructor that you are capable of performing the welding task.
American Welding Society/AWS D1.1 2010 Edition code covers commonly welding process used carbon and low-alloy constructional steels and welding requirements for any type of welded structure. Clauses 1 through 8 constitute a body of rules for the regulation of welding in steel construction. There are eight normative and twelve informative annexes in American Welding Society/AWS D1.1 2010 Edition code. A Commentary of the American Welding Society/AWS D1.1 2010 Edition code is included with the document.
Significant changes in American Welding Society/AWS D1.1 2010 Edition:
# new prequalification variable tables and accompanying commentary added to clarify what variables must be listed on prequalified WPSs and what ranges they are allowed # thermal cut requirements were changed
# matching and undermatching table in the prequalification section was revised to clarify intent
# weathering steel requirements were expanded to include more materials
# shelf bar requirements were added
# weld profile requirements were clarified and slightly revised
# weld access hole and beam cope requirements were revised and clarified
# issue on CVN qualification was clarified to avoid unnecessary testing
# three new materials were added to the list of prequalified materials
# headed stud requirements revised and clarified for burst cracks
# backing requirements revised to allow discontinuous backing in limited applications
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Step how to make Welding Procedure Specification
1. Drawing
Check the existing drawing. Check the type of material used in the welding process and included in the group (Group I, II, III, IV). Metal material type / base used refers to the code, the code used must be the last edition. sample used AWS D1.1. For metals, AWS D1.1 Table 3.1 standards used. Check the thickness of the material, joint preparation, the common position of mixed type. Check weld symbol used to determine the edge preparation, mixed type to Angle (Angle Groove).
2. PWPS (Preliminiary Welding Procedure Specification)
Materials information contained in the drawings in public works programs. In a letter to public works programs have a head that contains: Project name, number of forms, documents no., revision no., support for PQR no., date, page No, PWPS no.
For the design of the board should be developed and wrote the material thickness, the angle of the slot away from the root, the root and the face has been described as the welding sequence as well.
Check the electrical parameters such as amplifier and Voltage Range (root, hot, filling, capping), polarity, ground speed, the heat input.
Check supplies, i.e. the type, class, AWS specification, the size of the electrodes (electrode diameter).
Check the welding process, namely the Common Position, secondary (root, hot, filling, capping), do not pass welding.
To supply the information that has been written according to the welding process, Flux uses, Shield Gas, Flow Rate, Back Purge, Stick Out (root), Stick Out (fill), Consumable Treatment.
Electrode numbering included: Electrocde No, Nozzle Diameter, Wire Feeder.
Heat treatment, which is a description: Preheat, Temperature Check Methode, Max Interpass Temperature. Post Weld Heat Treatment(PWHT): thickness, temperature and time.
After the procedure the column should be, among others: elaboration, comments, Approved, Customer Representative (Part 3)
Technical: Rating position, increasing the welding refers to the AWS D1.1 Table 4.1
NDT: test methods used visual inspection, MPI, DPI, RT, UT reached 100% standard AWS D1.1 Table 6.1 For the mechanical tests, Test Method for Tensile, root Bend, side Bend ,face bend as per AWS D1.1 Table 4.2
3. Welding as per PWPS (Preliminiary Welding Procedure Specification)
These public works programs of the data used to guide the welding process. All data contained in the welding process is stored Procedure Qualification Record(PQR). Ampere and voltage range obtained in the process of welding the root, hot, filling, capping must be recorded. Also, the travel speed, heat input, electrode diameter should be recorded.
4. Welding Inspection:
a. Visual inspection, conducted 100% record at PQR, if the data to accept or reject, according to AWS D1.1 Table 6.1
b. NDT : MPI (carbon steel), DPI (stainless steel), RT, UT. All data should be recorded at PQR, accept or reject according to AWS D1.1 Table 6.1.
Then perform the mechanical test, the standard used by AWS D1.1 Table 4.2. Representative clients for its implementation should be witness. The results should be recorded accept or reject the PQR. If, therefore, accept the results of the weld is considered good, then you should do if Reject retest or repair. If the test result actually reject the welding process must be repeated.
After visual inspection, non destructive testing(NDT), test results that meet Mechanical and use can be prepared for the WPS and must be approved by stakeholders.
Mechanical testing usually refers to the client if the client has requested an additional test machine then you should do, even if not contained in the standard specification for customers is the highest level.
If the customer requests Spec hardness test macros are usually carried out and the two online tests.
5. Accept the PQR data is ready for WPS.
The welding Procedure Specification (WPS) has a header that contains: Project Name, Form No, Document No, Revision No, Supporting PQR No, Date, Page No, WPS No, Material Spec.
6. After all data are true and approved by the clients and 3rd party, then the PQR become approved WPS.
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API 1104 Welder & WPS Qualification Test
For pipeline construction as per American Petroleum Institute/API 1104 and also oil and gas projects, the welder and Welding Procedure Specification(WPS) needs to be qualified in advance to assess welder skill in welding process. Every welding code that is used in general has given rules to qualify a Welder and Welding Procedure Specification(WPS). Below are the steps and requirements necessary to qualify pipeline welder.
A. A change from one welding process to another welding process , or combination of process, as follows :
1. A change from one welding process to a different welding process or,
2. A change in combination of welding process, unless the welder has qualified on separate qualification test, using or each welding process that are to be used for the combination of welding process.
B. A change in the direction of welding from vertical uphill to vertical downhill or vice versa
C. A change of filler metal classification from group 1 or 2 to group 3, or from group 3 to group 2 or 1 ( see table 1)
D. A change from one outside diameter group to another.These groups are defined as follows :
1. Outside dia less than 2.375 in (60.3 mm)
2. Outside dia from 2.375 in (60.3mm) through 12.75 I (323.9 mm)
3. Outside dia greater than 12. 75 in (323.9mm)
E. A change from wall thickness group to another.These group are defined as follows :
1. Nominal wall pipe thickness less than 0.188 in ( 4.8mm)
2. Nominal wall pipe thickness from 0.188 in ( 4.8mm) through 0.750 in (19.1 mm)
3. Nominal wall pipe thickness greater than 0.75 in ( 19.1 mm)
F. A change in the position from that for which the welder has already qualified (for example, a change from rolled to fixed or change from vertical to horizontal or vice versa). A welder who successfully pass butt-weld qualification test in the fixed position with the axis inclined 45° from the horizontal plane shall qualified to do butt-weld and lap fillet welds in all position.
G. A change in the joint design ( for example, the elimination of a backing strips or a change from V bevel to U bevel)
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Below some common question and answer about Welded Steel Tanks for Oil Storage
as per API 650 : Question : Does API 650 provide a way to obtain a frangible roof connection on a small tank describe as follows? - Diameter: 8 ft. - Height: 10 ft. - Cross sectional area of the roof-to-shell junction "A": larger than that allowed by the equation in Section 3.10.
Answer : No. The API Subcommittee on Pressure Vessels and Tanks is currently reviewing the design criteria for frangible roof joints. You may wish to review Publication 937, Evaluation of Design Criteria for Storage Tanks with Frangible Roof Joints.
Question : Section 10.4.3 states "When considering dead loads only, including the weight of the rafters and the roof plates, the compression flange of the rafter shall be considered as receiving no lateral support from the roof plates and shall be laterally braced if necessary (see Section 3.10.4.2)." This statement, which is a fairly recent revision, imposes much more stringent requirements on the rafters than what was required in the earlier editions that allowed the assumption of lateral bracing from the friction with the roof plate. What was the basis for this change in requirements?
Answer : API does not respond to questions seeking the rationale for requirements in its standards. These requirements are based upon consideration of technical data and the judgment and skill of experienced engineering and technical personnel representing both users and manufacturers who serve on the standards-writing committees. All technical meetings during which API requirements are considered are open to the public. The API Pressure Vessels & Tanks Subcommittee, which is responsible for this standard, meets twice per year at the Spring and Fall Refining Meetings. Information on these meetings can be found on the API website at www.api.org/events.
Question : When installing girders and rafters in an existing tank, do they need to be installed in accordance with the latest edition of API Standard 650?
Answer : Yes, refer to API Standard 653, Section 9.11.1.2.
Question : When not altering the roof rafters and framing of an existing tank, is it necessary to upgrade it to the current edition of API Standard 650?
Answer : Refer to API Standard 653 Section 4.2.2
Question : Referring to 3.10.1(a) and 3.10.2.3, is it permissible by the code to locate rafters outside the tank over the roof plates? The rafters would hold the roof plates welded to its bottom flange instead of supporting the plate.
Answer : No, however, a committee agenda item has been approved that will change this requirement. Please refer to the next addendum of the standard.
Question : What does API 650, Section 3.10.2.5 mean by the term "top angle"?
Answer : Angle refers to a steel angle structural shape - see the AISC "Manual of Steel Construction" or other similar publications. It is usually a 90 degree shape but can be other angles. The "top angle" is the structural angle, purchased or fabricated, that is located at the top of the shell .
Question : Can the roof plate be attached to the top angle with a groove weld on top and a fillet weld on the inside?
Answer :No
Question : Refer to API 650, Section 3.10.2.5.1 and Figure F-2. Is the area "A" the crosshatched area in Figure F-2?
Answer :Yes
Question : Are roof support trusses which are welded to the shell acceptable?
Answer : API doesn't provide design detail attachment of roof trusses to the shell. Please refer to Section 3.10.2.7.
Question : In section 3.10.5 for self-supporting roofs, may the corrosion allowance be added to the minimum calculated thickness given by tmin = D/400 sin Ø to arrive at a total minimum required thickness of 3/16 in. or greater?
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American Welding Society(AWS) Code and Specifications
If you're in the construction business and adapting to the life of engineering drawings, is responsible for being familiar with the American Welding Society(AWS).
Why? Because the American Welding Society(AWS) is the only fat in the boonies surprising that the configuration of welding codes and specifications. And if you fill a job and a business ambassador welding third request certificates of analysis of the welding, you're screwed affectionate. You are not acquiring the analysis of a set of ambassador for up to date certifications set so shocked. Distant as OLE, says Jerry "the mule has left the barn"
"But I do not charge for certified welders," they say. Really? Read their assets. If you see the article in the sequel to "welding performed in accordance with American Welding Society(AWS) D1.1" the agency of its welders charge for certification in the welding to adhere to the requirements of the cartoon.
You can accept been accepted abroad without acceptance for years. But in the end, could amount a long time.
There are too rich to take account of American Welding Society(AWS) codes, but I have the welding codes more acclimated to your account and if you are in an industrial area of the codes referred to in the drawings, their ability to appetite for code and specifications.
AWS D1.1 Structural Welding Code – Steel
AWS D1.2 Structural welding code- Aluminum
AWS D1.3 Structural Welding Dode-Sheet Steel
AWS D14.1Specification for Welding of Industrial and Mill Cranes and Other Material Handling Equipment
AWS D14.3 Earth moving and construction equipment
AWS B2.1 Specification for Welding Procedure and Performance Qualification
AWS A3.0 Standard Definitions: Including Terms for Adhesive Bonding, Brazing, Soldering, Thermal Cutting and Thermal spraying
Load the capacity of all American Welding Society(AWS) codes listed above sea level, but an analysis and consideration of the additives in the alpha of his drawings. If you see that little account "welding is done in accordance with American Welding Society(AWS) ..." You are responsible for the excavation and added a bookstore to load encryption to do to meet American Welding Society(AWS) environment.
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The Piping Specification is a document prepared during the design phase of any project. It provides the appropriate selection, specification and material grade of pipe and piping components for a given service. For all subsequent maintenance and repair on a section of pipe, the piping specification remains as the key to correct material selection.
Before commencing any job, reference to the piping specification is essential to specify and use the correct materials. For the job check that you are using the latest revision of the specification.
Do not rely on “what was installed before must be right” as this is not always the case! If a discrepancy is found, it should be reported.
Note that a piping specification only applies to the defined plant, site or installation. Forties, Magnus, Dimlington Terminal for example each have their own piping specifications and they are NOT interchangeable. To use the piping specification, reference must first be made to the Process and Instrument Diagram. Identify the section of pipe in the
P&ID and a line number will be quoted, e.g:
8’’-WF-1007-1A1E which is interpreted as follows:
8’’ - The nominal pipe size of the line.
WF - The service code. This refers to the contents of the pipe. In this instance,WF refers to Fire Water .
1007 - The pipeline number which is a unique number allocated to a specific section or run of pipe during the design stages.
1A1E - The piping specification number. This is a short-hand reference into the piping specification document, and is
also unique to that document. The letter normally refers to the pressure rating of the system.
Having determined the piping specification number , turn to the appropriate page in the piping specification document. There the correct type of gasket, the correct grade of studbolts, spectacle blinds, blind flanges, pipe material, pipe wall thickness and much more will be specified for the job in hand.
Reference : BP Amoco Piping Joints Handbook (Document No. D/UTG/054/00)
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Pipe Joint Standards
The following Standards are relevant to pipe flanged joints:
RP 42-2 Bolting for Flanged Joints (Inch Series)
GS 142-4 Flanges
GS 142-5 Fittings
RP 42-1 Piping Systems
GS 142-7 Gaskets and Jointing
Below American Standards(ANSI/API Standards) are used for the standardization of pipe joints: ANSI BI.1 Unified Inch Screw Threads (UN and UNR Thread Form)
ANSI BI.20.1 Pipe Threads, General Purpose (Inch)
ANSI B16.5 Pipe Flanges and Flanged Fittings
ANSI B16.21 Non-Metallic Flat Gaskets for Pipe Flanges
API 601 Metallic Gaskets for RF Pipe Flanges and Flanged Connections
API 6A Specification for Wellhead and Christmas Tree Equipment
ANSI B16.47 Large Diameter Steel Flanges (NPS26 through NPS60)
ANSI B16.9 Factory made Wrought Steel Butt Welding Fittings
ANSI B16.11 Forged Steel Fittings, Socket Welding and Threaded
ANSI B16.20 Ring-Joint Gaskets and Groves for Steel Pipe Flanges
API 605 Large Diameter Carbon Steel Flanges
ANSI B16.1 Cast Iron Pipe Flanges and Flanged Fittings
BS 1560 Steel Pipe Flanges and Flanged Fittings
BS 3381 Metallic Spiral Wound Gaskets for Use with Flanges to BS 1560
BS 1832 Oil Resistant Compressed Asbestos Fibre Jointing
BS F125 Rubber Bonded Compressed Asbestos Fibre Jointing
BS 3293 Carbon Steel Pipe Flanges (over 24” NB) for the Petroleum Industry
BS 3799 Steel Pipe Fittings, Screwed and Socket-Welded for the Petroleum Industry
BS 1580 Specification for Unified Screw Threads
Reference : BP Amoco Piping Joints Handbook (Document No. D/UTG/054/00)
