British Buttress (BBUT) U-Type Threading Inserts – 22U / 27U Heavy Duty Series
Ideal for: Heavy Industrial Presses, Large Screw Jacks, Unidirectional Actuators.
- Product Series: Heavy-Duty British Buttress (BBUT) U-Type laydown threading inserts (Full Profile).
- Coarse Pitch Specialist: Engineered specifically for large British Buttress threads with 4 TPI and 3 TPI pitches.
- Asymmetric Power: Features the standard 7°/45° profile to transmit extreme axial loads in one direction.
- Maximum Stability: Large U-Type format (1/2″ and 5/8″ I.C.) provides rigidity for deep cuts that standard 16er threading inserts cannot handle.
-
Versatility: Premium threading inserts for lathe holders, available in both Right-Hand and left hand thread insert configurations.
Contact our sales team to discover all of your pricing options.
Product Overview
Tackle the largest unidirectional power threads with our British Buttress U-Type laydown threading inserts. While standard tools handle medium pitches, these heavy-duty carbide threading inserts are designed for the extreme forces required to machine coarse BBUT threads (7° pressure flank, 45° clearance flank).
Featuring a “Full Profile” geometry, these inserts cut the full thread depth and finish the crest in a single operation. The U-Type design utilizes a larger insert size to provide the structural integrity needed for 4 TPI or 3 TPI threads—tasks that are impossible for a standard 16er threading insert to perform due to the depth of cut required.
Key Features & Benefits
- Extreme Load Capacity: The 7° load-bearing flank transmits massive axial force, while the U-Type insert body prevents vibration during machining.
- Coarse Pitch Specialist: Specifically designed for 4 TPI and 3 TPI threads found on heavy British machinery.
- Comparison: A standard 16er threading insert (3/8″ I.C.) lacks the mass to support these coarse threads; our 22U and 27U series are the dedicated solution.
- Directional Options: We stock comprehensive solutions, including left hand thread insert models (e.g., 27U EL 3 BBUT) for counter-rotating mechanisms.
BBUT U-Type Threading Inserts Technical Specifications
| I.C. | Pitch (TPI) | External Model (R/L) | Internal Model (R/L) | L | X | Y |
|---|---|---|---|---|---|---|
| 1/2″ U | 4 | 22U ER4BBUT / 22U EL4BBUT | 22U IR4BBUT / 22U IL4BBUT | 22 | 2.3 | 9.5 |
| 5/8″ U | 3 | 27U ER3BBUT / 27U EL3BBUT | 27U IR3BBUT / 27U IL3BBUT | 27 | 3.1 | 11.7 |
(Note: U-Type inserts cover both External and Internal threading applications with the appropriate holder).
Machining Guidelines
- Tool Holder Requirement: These are U-Type threading inserts. You must use a compatible U-Type tool holder (22U or 27U pocket size). They will not fit standard 16er threading inserts holders.
- Orientation: BBUT threads are asymmetric. Ensure the 7° flank is oriented correctly relative to the load. Use a left hand thread insert for specific feed directions or reverse threads.
-
Machine Setup: Machining 3 TPI threads generates significant torque. Ensure your threading inserts for lathe setup is rigid and the workpiece is securely supported.
Need a consultation? Contact us！
Contact our sales team to discover all of your pricing options
