Thermal spraying - Thermally sprayed coatings - Symbolic representation on drawings (ISO 12671:2021); German version EN ISO 12671:2021
1Key Takeaways
This standard prescribes the rules to be applied for the symbolic representation of thermal sprayed coatings on drawings.
2Expert Interpretation
An in-depth interpretation of DIN EN ISO 12671:2021, the symbolic representation standard for thermal spray coatings in engineering drawings, covering the symbol system composition, marking position rules, coating naming specifications and implementation cases. It is suitable for the preparation of standardized drawings in fields such as mechanical manufacturing, aerospace, etc.
Analysis of the core content of the standard
DIN EN ISO 12671:2021 standard provides unified specifications for the symbolic representation of thermal spray coatings in technical drawings.
| Element type | Symbol example | Function description |
|---|---|---|
| Basic symbol | TS | Identification of thermal spray process |
| Additional symbol | BC/TC | Distinguish between bonding layer (BC) and working layer (TC) |
| Process symbol | APS/PFS | Atmospheric plasma spraying/powder flame spraying |
Typical application case
Case 1: Composite coating marking
ISO 12671-TS-TC-APS-ISO 14232-1:2017-Al2O3-TiO2 60/40-250-as
Indicates: Atmospheric plasma spraying (APS) process is used according to ISO Al2O3-TiO2 (60/40) powder prepared according to ISO 14232-1:2017, coating thickness 250μm, as-sprayed (as)
Case 2: Post-processed coating
ISO 12671-TS-TC-PFS-ISO 14232-1:2017-NiCrBSi 83 10-350-f+m/c
Indicates: Powder flame sprayed (PFS) NiCrBSi alloy coating, 350μm thickness, requiring remelting (f) and subsequent machining (m/c)
Implementation points
- Drawing annotation location: The symbol system should include the coating identification (outside the outline), guide lines, reference lines, and process parameters
- No-spraying area treatment: sprayable areas are marked with wide dashed lines, and unmarked areas are prohibited from spraying by default
- Patent process marking: when a patented process is used, the patent number or supplier code must be indicated
Technology evolution analysis
This standard inherits and develops the technical framework of basic standards such as ISO 1302 (surface roughness marking) and ISO 14232-1 (spray powder). Its symbol system design reflects the following:
- Modular structure: functional extension is achieved through basic symbols + additional symbols
- Process compatibility: the "X" mark allows free selection of spraying process
- Digital connection: supports data connection with PLM/PDM systems