New Vs Old Welding Cable

At the present time, there is welding cable manufacturers who prefer the lower the quality of their products rather than having to boost production costs which will result in a higher selling price. see how they reduce the volume of copper inside the cable that causes:
1. Cable conductivity decreases
2. Cable quickly became a hot
3. Cable fast peeling
4. Safety aspect of the welder
Picture attached is a welding cable with a size 70, so please be more careful when buying a product, it could be the items that you purchased does not accordance with the way you expect.
Cheers... :)

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BASIC ELECTRODES

Basic electrodes are so named because the covering is made with a high
proportion of basic minerals/compounds (alkaline compounds), such as calcium
carbonate (CaCO3), magnesium carbonate (MgCO3) and calcium fluoride (CaF2).
A fully basic electrode covering will be made up with about 60% of these basic
minerals/compounds.
Characteristics of basic electrodes are:

- The basic slag that forms when the covering melts reacts with impurities, such as sulphur and phosphorus, and also reduces the oxygen content of the weld metal by de-oxidation

- The relatively clean weld metal that is deposited gives a very significant improvement in weld metal toughness (C-Mn electrodes with Ni additions can give good toughness down to ~ -90°C)
- They can be baked at relatively high temperatures without any of the compounds present in the covering being destroyed, thereby giving low moisture content in the covering and low hydrogen levels in weld metal
- In order to maintain the electrodes in a low hydrogen condition they need to be protected from moisture pick-up

- By means of baking before use (typically at ~350°C), transferring to a holding oven (typically at ~120°C) and issued in small quantities and/or using heated quivers (‘portable ovens’) at the work station (typically ~70°C)

- By use of vacuum packed electrodes that do not need to be re-baked before use
- Basic slag is relatively viscous and thick which means that electrode manipulation requires more skill and should be used with a short arc to minimise the risk of porosity
- The surface profile of weld deposits from basic electrodes tends to be convex and slag removal requires more effort

Metal powder electrodes contain an addition of metal powder to the flux coating to increase the maximum permissible welding current level. Thus, for a given electrode size, the metal deposition rate and efficiency (percentage of the metal deposited) are increased compared with an electrode containing no iron powder in the coating. The slag is normally easily removed. Iron powder electrodes are mainly used in the flat and H/V positions to take advantage of the higher deposition rates. Efficiencies as high as 130 to 140% can be achieved for rutile and basic electrodes without marked deterioration of the arcing characteristics but the arc tends to be less forceful which reduces bead penetration.

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Welding Electrode Clasification base on EN 499

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Rutile Electrodes

Rutile is a mineral that consists of about 90% titanium dioxide (TiO2) and is present in C & C-Mn steel rutile electrodes at typically ~50%.
Characteristics of rutile electrodes are:

1. They have a very smooth and stable arc and produce a relatively thin slag covering that is easy to remove
2. They give a smooth weld profile
3. They are regarded as the most ‘user-friendly’ of the various electrode types
4. They have relatively high ‘combined moisture’ content and because they contain typically up to ~10% cellulose they cannot be baked and consequently they do not give a low H weld deposit
5. Because of the risk of cracking they are not designed for welding of high strength or thick section steel (although electrodes are manufactured in classes E60xx, E70xx, E80xx the E60xx grade is by far the most commonly used)
6. They do not give high toughness at low temperatures (typically only down to about -20ºC)

The above listed characteristics mean that this type of electrode is used for general-purpose fabrication of unalloyed, low strength steels in relatively thin sections (typically ≤ ~13mm).
Rutile ElectrodeVariants
By adding iron powder to the covering a range of thick-coated electrodes have been produced in order to enhance productivity.
Such electrodes give weld deposits that weigh between ~135 and 190% of their core wire weight and so referred to as ‘high recovery’ electrodes, or more specifically for example ‘ a 170% recovery electrode’.
The weld deposit from such electrodes can be relatively large and fluid and this restricts welding to the flat position and for standing fillets for electrodes with the highest recovery rates.
In all other respects these electrodes have the characteristics listed for standard rutile electrodes.

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Cellulosic Electrodes

Cellulose is the principal substance in this type of electrode and comprising typically ~ 40% of the flux constituents.
Cellulose is an organic material (naturally occurring) such as cotton and wood, but it is wood pulp that is the principal source of cellulose used in the manufacture of electrode coverings.
The main characteristics of Cellulosic electrodes are:

1. Cellulose breaks down during welding and produces carbon monoxide & dioxide and hydrogen
   
2. Hydrogen provides part of the gas shielding function and gives a relatively high arc voltage
   
3. The high arc voltage gives the electrode a ‘hard’ and forceful arc with good penetration/fusion ability
   
4. The volume of slag formed is relatively small
   
5. Cellulosic electrodes cannot be baked during manufacture or before welding because this would destroy the cellulose; the manufacturing procedure is to ‘harden’ the coating by drying (typically at 70 to 100ºC)
   
6. Because of the high hydrogen levels there is always some risk of H cracking which requires control measures such as ‘hot-pass’ welding to facilitate the rapid escape of hydrogen
   
7. Because of the risk of H cracking there are limits on the strength/composition and thickness of steels on which they can be used (electrode are manufactured in classes E60xx, E70xx, E80xx & E90xx but both lower strength grades tend to be the most (commonly used)
   
8. High toughness at low temperatures cannot be consistently achieved from this type of electrode (typically only down to about -20ºC)

Application of Cellulosic Electrodes
Cellulosic electrodes have characteristics that enable them to be used for vertical-down welding at fast travel speed but with low risk of lack-of-fusion because of their forceful arc.
The ‘niche’ application for this type of electrode is girth seam welding of large diameter steel pipes for overland pipelines (Transco (BGAS) P2, BS 4515 & API 1104 applications). No other type of electrode has the ability to allow root pass welding at high speed and still give good root penetration when the root gap is less than ideal.
Because of their penetration ability these electrodes have also found application on oil storage tanks – for vertical and circumferential seam welding of the upper/thinner courses for which preparations with large root faces or square edge preparations are used.

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Welding Consumable

MMA/SMAW Electrodes, categorized by the type of covering(fluxes).
For C-Mn and low alloy steels there are 3 generic types of electrodes, namely:

1.  Cellulosic electrodes
2.  Rutile electrode
3.  Basic electrodes

These generic names indicate the type of mineral/compound that is dominant in the covering.
(to be continues...)

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WELDING ELECTRODE CLASSIFICATIONS

MILD STEEL COATED ELECTRODES

E7018-X

• E - Indicates that this is an electrode
• 70 - Indicates how strong this electrode is when welded. Measured in thousands of pounds per square inch.
• 1 - Indicates in what welding positions it can be used.
• 8 - Indicates the coating, penetration, and current type used. (See Classification Table below)
• X - Indicates that there are more requirements. (See Additional Requirements below)

WELDING POSITIONS

• 1 - Flat, Horizontal, Vertical (up), Overhead
• 2 - Flat, Horizontal
• 4 - Flat, Horizontal, Overhead, Vertical (down)
  Flat Position - usually groove welds, fillet welds only if welded like a “V”
  Horizontal - Fillet welds, welds on walls (travel is from side to side).
  Vertical - welds on walls (travel is either up or down).
  Overhead - weld that needs to be done upside down.
  

CLASSIFICATION TABLE
Class Electrode Coating Penetration Current Type
Exxx0 - Cellulose, Sodium Deep DCEP
Exxx1 - Cellulose, Potassium Deep AC, DCEP
Exxx2 - Rutile, Sodium Medium AC, DCEN
Exxx3 - Rutile, Potassium Light AC, DCEP, DCEN
Exxx4 - Rutile, Iron Powder Medium AC, DCEP, DCEN
Exxx5 - Low Hydrogen, Sodium Medium DCEP
Exxx6 - Low Hydrogen, Potassium Medium AC, DCEP
Exxx7 - Iron Powder, Iron Oxide Medium AC, DCEN
Exxx8 - Low Hydrogen, Iron Powder Medium AC, DCEP
Exxx9 - Iron Oxide, Rutile, Potassium Medium AC, DCEP, DCEN

ADDITIONAL REQUIREMENTS
Suffix Additional Requirement
-1 Increased toughness (impact strength) for E7018 electrodes. Also increased ductility in E7024 electrodes.
-M Meets most military requirements - greater toughness, lower moisture content as received after exposure,
diffusible hydrogen limits for weld metal.

-H4 Indicates the maximum diffusible hydrogen limit measured in millimeters per 100 grams (mL/100g). The 4, 8, and
-H8 16 indicates what the limit is. Example: -H4 = 4mL per 100 grams
-H16

LOW ALLOY STEEL COATED ELECTRODES

SUFFIX TABLE
Suffix Steel Alloy Type Suffix Number Description
-A1 Carbon-Molybdenum 0.40 - 0.65 Mo
-B1 Chromium-Molybdenum 0.40 - 0.65 Cr 0.40 - 0.65 Mo
-B2 Chromium-Molybdenum 1.00 - 1.50 Cr 0.40 - 0.65 Mo
-B2L Chromium-Molybdenum Lower Carbon B2
-B3 Chromium-Molybdenum 2.00 - 2.50 Cr 0.90 - 1.20 Mo
-B3L Chromium-Molybdenum Lower Carbon B3
-B4L Chromium-Molybdenum 1.75 - 2.25 Cr 0.40 - 0.65 Mo
-B5 Chromium-Molybdenum 0.40 - 0.60 Cr 1.00 - 1.25 Mo
-B6 was E502 4.6 - 6.0 Cr 0.45 - 0.65 Mo
-B8 was E505 8.0 - 10.5 Cr 0.8 - 1.2 Mo
-C1 Nickel Steel 2.00 - 2.75 Ni
-C1L Nickel Steel Lower Carbon C1
-C2 Nickel Steel 3.00 - 3.75 Ni
-C2L Nickel Steel Lower Carbon C2
-C3 Nickel Steel 0.80 - 1.10 Ni
-NM Nickel-Molybdenum 0.80 - 1.10 Ni 0.40 - 0.65 Mo
-D1 Manganese-Molybdenum 1.00 - 1.75 Mn 0.25 - 0.45 Mo
-D2 Manganese-Molybdenum 1.65 - 2.00 Mn 0.25 - 0.45 Mo
-D3 Manganese-Molybdenum 1.00 - 1.80 Mn 0.40 - 0.65 Mo
-W Weathering Steel Ni, Cr, Mo, Cu
-G No required chemistry
-M Military grade May have more requirements

Class Min. Tensile Strength Min. Yield Strength
E60xx 62,000 psi 50,000 psi
E70xx 70,000 psi 57,000 psi
E80xx 80,000 psi 67,000 psi
E90xx 90,000 psi 77,000 psi
E100xx 100,000 psi 87,000 psi
E110xx 110,000 psi 95,000 psi
E120xx 120,000 psi 107,000 psi

CHEMICAL SYMBOLS FOR THE ELEMENTS
C Carbon Most effective hardening element in steel
Mn Manganese Hardening element second to carbon
Si Silicon Deoxidizer, moderate strengthener
P Phosphorus Causes cracking if too high
S Sulfur Aids in machining - Cracking problems like P
Cr Chromium Hardness (low) - corrosion resistance (high)
Ni Nickel Hardening element - better cold toughness
Mo Molybdenum Hardenability - high temp tensile - creep strength
B Boron Very small amounts increase hardness
Cu Copper Corrosion resistance (low) - cracking (high)
Al Aluminum Deoxidizer - improves mechanical properties
Ti Titanium Removes: Oxygen, S, N, and C
N Nitrogen Improves strength - lowers toughness
Cb Columbium Hardness - Improves mechanical properties
V Vanadium Hardness - Improves mechanical properties

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Menghitung Welding Consumable untuk Piling Project

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