Instruction and Application: Low hydrogen type coating of low alloy heat-resistant steel electrode for sodium, has good resistance to fatigue cracking of welded joint performance, excellent resistance to temper embrittlement and its mechanical properties of welded joint of high operating characteristics of an electrode, and suitable for field installation and construction, and compared to ordinary steel welding material, has the following characteristics:

1. Deposited metal purity, impurities such as S and P is extremely low, S≤0.10%, P≤0.10%.

2. Excellent low temperature toughness of deposited metal, KV₂ ( -30℃) ≥54J.

3. Excellent resistance to temper embrittlement of weld metal, x factor is very low.

Used in the petroleum refining, petrochemical, coal chemicals, steam turbine cylinder, thermal power, nuclear energy and other harsh conditions, corrosive medium large, complex equipment ASME SA387 Gr. 22 Class 2 (12Cr2Mo1R) class steel plate welding.

Typical Chemical Composition of the all-welded metal(％)

X-factor = (10P+5Sb+4Sn+As) *10^-2

2Element type to ppm content into, such as 0.01% should be 100ppm into

Mechanical properties of all-weld metal

Note: Temper embrittlement test VTr54+2.5△VTr54≤10℃.

*In practice, the heat treatment system shall be formulated separately by the supply and demand parties or by the conditions of the working conditions (such as the thickness of the specimen).

H_D (Mercury method): ≤5.0ml/100g

Deposited metal radio-graphic testing:

According to NB / T 47013.2, the radio-graphic detecting technique should not be less than class AB and the quality grade of deposited metal should not be less than Class I.

Reference current (DC+):

Notice：

1. Redry the electrode at 350~400°C for 1~2hour.

2.Cleaning the oil stain, rust and moisture of the weldment surface before welding.

3.Operate with short arc and narrow bead welding method, preheating temperature about 150°C, the temperature between different welding bead should be controlled to 150~300°C.