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CBN Threading Inserts
Creating threads in hardened steel used to mean one thing: slow, costly grinding operations. Standard carbide inserts simply cannot hold the thread form in materials harder than HRC 50.
Sundi CBN Threading Inserts enable you to perform “Hard Threading” on your standard CNC lathe. By cutting the thread after heat treatment, you eliminate thread distortion issues and bypass the grinding bottleneck entirely. Experience superior productivity with thread profiles that rival ground quality.
Versatile Hard Threading Solutions
Sundi offers CBN threading inserts for all major international standards, suitable for both external and internal applications.
ISO Metric (M): Standard 60° threads for automotive and general machinery components.
Unified (UN / UNJ): Solutions for aerospace hard fasteners and fittings.
Whitworth (BSW / BSP): Profiles for pipe fittings and hydraulic connections.
API / Trapezoidal: Custom profiles available for oil & gas or motion control screws in hardened materials.
Ideal Applications
Sundi CBN Threading Inserts are essential for industries producing high-wear, high-strength components.
Ball Screws & Lead Screws: Hard turning the thread tracks in induction-hardened shafts.
Automotive Transmission Shafts: Machining threads on heat-treated input/output shafts.
Hydraulic Components: Threading cast iron valve bodies or hardened fittings.
Aerospace Fasteners: Cutting high-strength alloy threads (e.g., Inconel 718 with specific CBN grades).
- High wear resistance
- Reduce the machine time
- Stable Performance
- Easy to use
Why Choose Sundi CBN for Threading?
Threading is a demanding operation where the cutting tip is fully engaged. Sundi CBN provides the extreme hot hardness required to maintain the thread form without plastic deformation.
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1. Maintain Pitch Diameter Consistency
In hard threading, rapid flank wear on the tool leads to oversized pitch diameters (out of tolerance). Sundi CBN grades resist abrasive wear, keeping the thread dimensions stable for significantly longer runs compared to ceramic or carbide tools.
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2. Elimination of Secondary Grinding
By switching to Sundi CBN, you can machine the finished thread in the same setup as your hard turning operations. This reduces part handling, shortens lead times, and significantly lowers the cost-per-part compared to sending parts out for grinding.
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3. Burr-Free, Clean Profiles
Sundi CBN inserts feature precision-ground cutting edges that slice cleanly through the hardened matrix. This produces high-quality threads with smooth flanks and no burrs, often eliminating the need for subsequent deburring or polishing.
Rethink Your Threading Process
Why grind when you can turn? Unlock the speed and efficiency of Sundi CBN Threading Inserts for your hardened parts production.
FAQ
Most frequent questions and answers
A: No. CBN relies on the heat generated in cutting hardened materials to function correctly. In soft steel, chemical interaction will cause rapid crater wear and poor surface finish. For soft materials, stick to Sundi Carbide Threading Inserts.
A: Hard threading typically requires more passes with smaller depths of cut compared to soft threading. This reduces the cutting load on the CBN tip and prevents breakage.
A: For most hardened steel applications, Dry Machining is preferred to avoid thermal shock. However, if threading Cast Iron or if chip evacuation is critical (internal threads), oil mist or air blast is highly effective.