What temperature and time should the electrode be kept warm after drying?
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Now I have a question: What is the appropriate range of holding temperature and time after the welding rod is dried at the specified temperature? Are there any standards and regulations in this regard? Are there different types of welding rods (such as stainless steel, heat-resistant steel, etc.)? Thanks for the advice~~~
Welding rods often deteriorate process performance due to moisture absorption, causing arc instability, increased spatter, and prone to defects such as pores and cracks. Therefore, the welding rod must be strictly dried before use. Generally, the drying temperature for acidic welding rods is 150--200℃, and the time is 1 hour. ； The drying temperature of alkaline welding rod is 350--400℃, and the time is 1-2 hours. After drying, it is placed in an insulating box at 100--150℃ and taken out as needed.
There are recommended holding times and temperatures in JB4709 (non-mandatory standards), but our factory usually follows the baking temperature and time recommended on the welding rod box.
It is recommended to follow the drying and heat preservation times recommended by the welding rod manufacturer. Generally, there are detailed instructions on the outer packaging of the welding rod, and some have instructions inside the box.
Table 4 Commonly used welding consumables drying temperature and holding time (JB4709-2000) Category Brand Temperature T Time, h Carbon steel and low alloy steel electrode J422150lJ4263001J4273501J5021501J506, J5073501J506RH, J 507RH350——430lJ507MOW3501J5573501J556RH400lJ606, J6073501J607RH350～4301J7073501J707RH4002 low temperature steel electrode W607, W7 073501 Molybdenum and chromium-molybdenum heat-resistant steel welding rod R207, R307350lR307H4001R317, R407, R5073501 Chromium-nickel stainless steel welding rod A1021501A1072501A1321501A1372501A20215 01A207250lA002, A022, A212, A2421501 Chromium stainless steel welding rod G202150lG2072501G3021501G307200~3001 Melting flux HJ43l2502350, H1260300 ~ 4002250300~3502 Sintered flux SJl0l300~3502SJl02
I don’t think the recommended temperature on 4709 is very good. It is recommended to refer to the baking temperature and holding time provided by the welding material manufacturer.
Yes, every construction team has drying equipment, and every welder puts the welding rods in a box for immediate use.
Welding rods often deteriorate process performance due to moisture absorption, causing arc instability, increased spatter, and prone to defects such as pores and cracks. Therefore, the welding rod must be strictly dried before use. Generally, the drying temperature for acidic welding rods is 150--200℃, and the time is 1 hour. ； The drying temperature of alkaline welding rod is 350--400℃, and the time is 1-2 hours. After drying, it is placed in an insulating box at 100--150℃ and taken out as needed.
It is recommended to follow the drying and heat preservation times recommended by the welding rod manufacturer. Generally, there are detailed instructions on the outer packaging of the welding rod, and some have instructions inside the box.
I agree with the list on the fifth floor. When drying welding rods at work, I usually read the drying instructions on the welding rods, which have specific drying times.； But based on work experience, this is far from enough. We also need to look at the welding location. China has a vast territory, and the drying time of welding sites in the south and north is absolutely different. If you just read the instructions for drying the electrodes after welding, 80% of them will fail the flaw detection. In northern China and dry areas, the drying time specified in the instruction manual can be followed. However, in southern China and humid areas, the drying time specified in the welding rod instruction manual is far from enough. It is necessary to increase the drying time by about 1 hour according to different welding rods to ensure welding quality.
For commonly used carbon steel and low alloy steel welding rods, the holding temperature after drying can be referred to the appendix 5.1 and 5.5 of Part C, Volume II of the ASME Code. The holding temperature of different welding rods is different and the holding time is not specified.