What are the technical standards for stainless steel electrodes

1. Subject content and scope of application This standard specifies the type classification, technical requirements, test methods and inspection rules of stainless steel electrodes. This standard applies to stainless steel electrodes for manual electric arc welding. The chromium content in the deposited metal of this type of electrode should be less than 10.5%, and the content should exceed any other element. 2. Reference standard GB 223.1-223.70 Chemical analysis method for steel and alloy GB1954 Chromium-nickel austenitic stainless steel weld ferrite content measurement method GB2652 weld and deposited metal stretching test method GB4334.5 stainless steel sulfuric acid-sulfuric acid Copper corrosion test method
3. Type classification 3.1 Welding rods are classified according to the chemical composition of the deposited metal, the type of coating, the welding position and the type of welding current, as shown in Table 1 and Table 2. 3.2 Model preparation method The letter “E” means welding rod, and the number after “E” means the classification code of the chemical composition of the deposited metal. If there is a chemical composition with special requirements, the chemical composition is represented by the element symbol and placed after the number. The two digits behind the dash “-” indicate the electrode type, welding position and welding current type. 3.3 Examples of the electrode types in this standard are as follows: E 308 -15 ┬ ┬ ┬ ┬ ┬ ┬ ┬ └ Indicates that the electrode is alkaline coating, suitable for all positions, using DC reverse polarity welding │ └───Indicates the classification code of the chemical composition of the deposited metal └────Indicates the welding rod E 410-NiMo -26 ┬ ┬ ┬ ┬ ┬ ┬ Indicates that the electrode is alkaline or other types of coatings, suitable for flat welding and horizontal welding positions, using AC or DC reverse polarity welding │
│ │ └───Indicates that the content of Ni and Mo in the deposited metal has special requirements. │ └─────Indicates the classification code of the chemical composition of the deposited metal └───────Indicates the electrode Table 1 The chemical composition of the deposited metal (omitted) Table 2 Welding current and welding position

Electrode model
Welding current
Position of welding

EXXX(X)-15
DC reverse connection
Full location

EXXX(X)-25
Flat welding, horizontal welding

EXXX(X)-16
AC or DC reverse connection
Full location

EXXX(X)-17

EXXX (X)-26
Flat welding, horizontal welding
Note: All-position welding is recommended if the diameter is equal to and greater than 5.0mm.
4. Technical requirements 4.1 Size 4.1.1 The size of the welding rod should meet the requirements in Table 3. Table 3 Welding rod size mm

Electrode diameter
Length of electrode

basic size
limit deviation
basic size
limit deviation

1.6, 2.0
-0.08
220-260
±2.0

2.5
230-350

3.2
300-460

4.0, 5.0, 6.0
340-460
4.1.1.1 It is allowed to manufacture electrodes with a diameter of 3.0 mm instead of 3.2 mm electrodes, and electrodes with a diameter of 5.8 mm instead of 6.0 mm electrodes. 4.1.1.2 According to the agreement between the supply and demand parties, other sizes of welding rods are allowed to be supplied. 4.1.2 The length of the welding rod clamping end should meet the requirements in Table 4. Table 4 Length of clamping end mm

Electrode diameter
Length of clamping end

≤4.0
10-30

≥5.0
20-40
To
4.2 Coating 4.2.1 There should be no defects such as cracks, bubbles, impurities and spalling on the coating of the welding rod that affect the quality of welding. 4.2.2 The arc starting coating of the welding rod should be chamfered, and the end face of the welding core should be exposed to ensure easy arc ignition. The exposed core of the welding rod should meet the following requirements: a. The diameter of the welding rod is not greater than 2.0mm, and the core is exposed along the length. The length should not be greater than 1.6mm; b. For electrodes with diameters of 2.5mm and 3.2mm, the exposed core length along the length should not be greater than 2.0mm; c. For electrodes with a diameter greater than 3.2mm, exposed cores along the length The length should not be greater than 3.2mm; d. The exposed core of various electrode diameters along the circumferential direction should not be greater than half of the circumference. 4.2.3 The electrode coating should have sufficient strength so as not to be damaged during normal handling or use. 4.2.4 The eccentricity of the electrode should meet the following requirements: a. The diameter of the electrode is not greater than 2.5mm, and the eccentricity should not be greater than 7%; b. The diameter of the electrode is 3.2mm and 4.0mm, and the eccentricity should not be greater than 5. %; c. The diameter of the electrode is not less than 5.0mm, and the eccentricity should not be greater than 4%. The eccentricity calculation method is as follows (see Figure 1): T1-T2 Welding rod eccentricity = 100% (T1 + T2) 2 / Maximum layer thickness of welding rod: T1-2-Thickness of welding rod The minimum thickness of the cross-section coating + the diameter of the welding core.​​​​​​​​
4.3 Fillet welds of T-shaped joints 4.3.1 The surface of the fillet welds shall be free of cracks, weld beads, slag inclusions and surface pores after visual inspection. 4.3.2 The section of the fillet weld shall meet the following requirements after being polished and corroded: a. The fillet weld on each side shall be fused or melted through the junction of the two plates; b. The foot of the fillet weld on each side The difference between the size and the length of the two welding feet should meet the requirements of Table 5. C. After visual inspection, there must be no cracks in the cross section of the fillet weld; d. The weld must not have slag inclusions and pores.