Surface cleanliness

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• Cladding requires a pre-treatment process using tools of the same or similar material (chipper, brushes, etc.).
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• Generally, stainless steel is mainly used.
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• In the case of nickel alloy, it is most important to prevent contamination from the Sulfur.
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• Surface cleanliness through thought work must be made using SUFUR-FREE grinder material.

Welding design

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• Generally, the required chemical components of cladding are available through 3 layer cladding
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• Allow 2 to 3mm cladding thickness by layer
*If the cladding thickness is limited, the first and second layer should be thought-out as necessary.

Preheating and interlayer temperature

• - Welding of raw materials
  Refer to EN1011-2 for information on chemical composition, thickness, and minimum preheating temperature according to the welding process.


• - Welding of buffers
  Most buffered welds use austenitic welds that give the base material a minimum amount of hydrogen. Therefore, warm-up temperatures are sometimes slightly lower than calculated.
  • - Approximately 50C low for SMAW
  • - Up to 100C low when welding GMAW, GTAW, FCAW and ESW/SW Strips

Stress removal annealing

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• Generally, stress removal annealing of rolled-bonded clad pipes is required only when the base material is needed.
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• Stress removal annealing is not good for cladding and welds due to carbs and metal reclamation
* Stress removal annealing should be avoided as much as possible.

Cladding postprocessing

Since the smooth handling of the weld bead prevents formal corrosion and prevents discoloration by Pickling, postprocessing similar to the flattening of the cladding according to the material and the corrosion medium must be considered.

• When welding a clad pipe spool, it is essential that the base material and cladding are not mixed.
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  • Prevent hardening of welds and high temperature cracks
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  • Consideration is always given to maintaining the actual thickness of the cladding during the pre-process.
• Welding of the base metal must be made on the base metal to prevent mixing or contamination with the cladding in advance.
• Since titanium and carbon steel do not weld each other by the osmosis of hard metal reclamation compounds, an intermediate insert must be required to bond the carbon steel with the titanium cladding.