CAT (ANSI B5.50) Technical Information
CAT tool holders are widely used in CNC machining and are designed to ANSI/ASME B5.50 standards for reliable spindle interface and consistent machining performance.
Correct Standard Selection is Essential
CAT and SK holders follow different standards and should not be treated as direct substitutes. Matching the holder to the correct spindle standard is necessary for safe operation, proper fit, and machining accuracy.
Can CAT Holders Be Used Instead of SK Holders?
No. CAT series holders should not be used in place of SK series holders because the two systems are based on different standards and spindle interface details.
CAT Series
- Standard: ANSI/ASME B5.50.
- Commonly used in North American machining environments.
- Designed for machines built for CAT spindle compatibility.
SK Series
- Standard: DIN 69871.
- Also referenced under DIN ISO 7388-1.
- Designed for machines built for SK spindle compatibility.
Note: Always verify spindle standard, flange form, and pull stud specification before selecting a tool holder.
