Comparison | PGM quality | Common quality |
Carbide Tip type and size | PGM certified with strict filtering | No |
Size criteria | Parameters such as tip angle, shank diameter, spiral thickness etc. are designed and calculated by professional German company to maximize the drilling performance and effective dust removal. | No fixed design parameter or purposes. |
Soldering | PGM requires auto brazing with controlled brazing tip length and mechanically centralized tip. | Manual soldering, soldered by experience, no accurate tip positioning. |
Heat treatment | Special vacuum heat treatment technique according to PGM requirement, ensure the high breaking tenacity of the bit shank to match the life time of the wear-resistant and tough tungsten tip. | Normal 40Cr steel or carbon steel heat treatment. HRC can reach similar rank but the inner structure cannot ensure high breaking tenacity or long time wear-resistant. |
Surface treatment | Specific shot-peening technique removes the shank stress points to create high torque strength and reduce flute wear, prolong the shank life, make the bit with bright and smooth surface. | Sand blasting, cannot remove the shank stress points, easy to rust. |
Anti-rust treatment | Anti-rust period above 2 years thanks to the PGM standard premium anti-rust oil. | Common aqueous or dry anti-rust oil, with anti-rust period around one year. |
comparison | Auto-copper alloy soldering | Common manual brazing |
Soldering flux | Special copper flux prescription with higher melting point | Copper wire/strip with 10-25% silver, or common pure copper, with 700-850°C melting points. |
Brazing temperature | 1200-1250°C brazing temperature ensures the drill bit with a higher heat-resistant performance when in continuous drilling, the strong attachment of the copper flux prevents the tip from falling. | 700-850°C |
Soldering process | Inside the vacuum brazing oven, gradually warming up ensures the steady character of the tungsten tip, not easily become fragile. | Instant heat up destroy the inner structure of the tungsten tip to become fragile,breakage happen during drilling. |
Soldering strength | Melted copper flux assures proper and complete distribution of copper brazing elements to attach the tip and shank as a whole. Then longer life time is ensured. | Manual soldering, soldering flux not evenly distributed, open or inconsistent soldering easily appear. The unevenly distributed soldering flux always cause the tungsten tip dropping in big diameter drill bits. |