中文
Flux drying insulation control
Welding Wires Manufacturers before use, first by the provisions of the flux manual baking, drying specification is based on test and process control testing, quality assurance of accurate data, which is an enterprise standard, different business requirements specification, followed by According to the steel pressure vessel welding procedures JB4709-2000 << >> recommended flux drying temperature and hold time. The general flux drying, stack height does not exceed 5cm. Welding consumables libraries often in a the drying number of multi-generational less, the stacked thickness to thick-generation thin, this should be strictly managed to ensure the quality of flux drying. Avoid stacking too thick, by extending the drying time to ensure that the flux baking Through.
2. Flux control of on-site management and recycling disposal
Welding parts should be clean, avoid debris mixed with flux, including flux pad with flux according to the provisions of issuance, it is best to stand at about 50 ℃ in a timely manner flux recovery and avoid pollution; repeatedly use flux 8-mesh and 40-mesh sieve were sieved and remove impurities and fine powder, mixed with three times the new flux are. Must be dried at 250-350 ℃ before use and held for two hours, after drying in the 100-150 ℃ incubator save to prepare for the next reuse prohibited in open storage. Complex scene or relative environmental humidity, good management of the operation site in a timely manner, to keep clean flux necessary moisture resistance and mechanical mixture of the test, control moisture absorption rate and mechanical inclusions avoid cluttered flux mixed.
3 the size of the solder particles and distribution requirements
Welding Flux of pores of the molten pool of air pollution. The flux is generally divided into two types, a common particle size of 2.5-0.45mm (8-40 mesh), another is a fine-grained 1.43-0.28 mm (10-60 mesh). The fine powder of less than a predetermined particle size is generally not more than 5%, greater than the predetermined particle size the MEALS generally greater than 2%, to do the testing and control of distribution of the degree of solder particles, to determine the use of the welding current. Attachment: flux particle size range of welding current relationship between particle size / mm 2.5-0.45 0.28-1.43 welding current / A <800 600-1200
Flux granularity and heap scattered high degree of control
The solder layer is too thin or too thick will be caused in the weld surface pits, spots and pores, to form a smooth bead shape, the thickness of the solder layer to be strictly controlled within the range of 25-40mm. When agglomerated flux density flux piled high, higher than the melting flux of 20% -50%. The higher the larger the wire diameter of the welding current, high flux thickness corresponding increase; operation of the welding process is not standardized, the fine powder unreasonable disposal of flux, the weld surface appears uneven pits intermittent, non-destructive testing of qualified but The appearance quality affected by the local weakening of the housing thickness.
Structural characteristics, conditions of use should be based on the chemical composition of the base metal, mechanical properties, weldability and combined pressure vessel
And welding method takes into account the selection of Welding Wires Manufacturer , if necessary, determined by experiments.
The performance of the weld metal should be higher than or equal to the corresponding base metal standard specifies the value of the lower limit or to meet the design requirements of the
technical conditions
Requirements.
All kinds of steel weld metal requirements are as follows
The Welding Consumables standard or product samples listed on the performance welding consumables melting performance of the deposited metal (excluding base metal), while the welding
The joint performance depends on the weld metal (including welding; the material deposited metal and base metal) and welding process, there is no any welding
Material role in the welding process can change the performance in the heat affected zone of the welded joint, from the selection of welding material.
Only consider the performance of the weld metal, in order to ensure the performance of welded joints will be welded process (especially post-weld heat treatment, heat input)
Cooperation. JB/T4709-2000, in principle, provides that "the performance of the weld metal should be higher than or equal to the the standard specified value of the corresponding base material
under
Limit or to meet the technical conditions prescribed pattern requirements "as a general principle of selection of welding materials:
The JB/T4709-2000 will GB in 150 low-alloy steel according to their performance is divided into strength low-alloy steel, heat-resistant low
Alloy steel and low alloy steel, low temperature so that the division actually adapt their welding characteristics.
Some people think that the assessment by the welding process, the welding material, "this argument is not comprehensive - for example, welding
16MnR steel, the following electrode welding procedure qualification: J506, J507, J507R, J507G, J507RH,
J507DF ...... but welding products which grades will have to consider many other factors, such as: (1) from the welding equipment to consider, J506 make
AC welder, J507 DC welder; â‘¡ from the crack resistance consider J507RH better than J507 welding inside the container; C
From labor protection considerations, J507DF (low dust) is superior to J507; (4) improve efficiency considerations, iron powder electrode J507Fe better than
507. After comprehensive consideration of the above factors ultimately determine the electrode grade.
