Mitsubishi MMT16IR250ISO-S VP15TF Internal Threading Insert
30-Day Free Returns
Free Worldwide Shipping
MMT16IR250ISO-S VP15TF
Mitsubishi Materials | Internal ISO Metric Threading | 2.5mm Pitch
The Mitsubishi MMT16IR250ISO-S VP15TF is a heavy-duty internal threading insert engineered for large-pitch 2.5mm ISO metric threads (standard for M18 to M22 fasteners). As a flagship component of the MMT series, this insert features the specialized -S type 3D molded chipbreaker. This is critical for internal CNC threading where the volume of material removed per pass is significant; it ensures chips are curled tightly and evacuated safely from the bore. Coated with VP15TF Miracle PVD, it offers industry-leading performance when threading stainless steel, alloy steels, and ductile iron.
Technical Specifications
| ISO/Metric Designation | MMT16IR250ISO-S |
|---|---|
| ANSI Equivalent (Inch) | 16IR 2.5 ISO-S (3/8" IC) |
| Thread Profile / Angle | ISO Metric 60° (Full Form) |
| Thread Pitch | 2.5 mm |
| Grade / Coating | VP15TF (Miracle Al-Ti-N PVD) |
VP15TF Miracle Grade
The VP15TF grade is a micro-grain carbide substrate combined with Mitsubishi’s proprietary Miracle (Al-Ti-N) coating. This grade is the gold standard for indexable threading due to its incredible heat resistance and toughness. It excels in preventing built-up edge (BUE), making it the preferred choice for 300 and 400 series stainless steels and gummy low-carbon steels.
-S Type 3D Chipbreaker
Large 2.5 pitch internal threads produce thick, stiff chips. The -S molded geometry is designed to reduce cutting resistance by up to 20% compared to flat inserts. It curls chips away from the thread flank, protecting the internal thread surface finish and significantly extending the life of your threading boring bar.
Recommended Cutting Parameters
| Workpiece Material | Cutting Speed ($v_c$) | Recommended No. of Passes |
|---|---|---|
| Carbon Steels (P10-P30) | 80 - 160 m/min | 12 - 18 |
| Stainless Steels (M10-M30) | 60 - 120 m/min | 14 - 22 |
| Alloy Steels (High Hardness) | 70 - 140 m/min | 13 - 20 |
MMTIR INTERNAL TOOLING SYSTEM
This 16IR insert is optimized for use with Mitsubishi MMTIR internal boring bars. Ensure the boring bar has sufficient clearance for a 2.5mm pitch profile.
Shop MMTIR Internal Bars →Metric vs. Inch Cross-Reference
| Feature | Metric (ISO Model) | Inch Equivalent (ANSI) |
|---|---|---|
| Insert Size | 16 IR | 3 IR (3/8" Inscribed Circle) |
| Thread Pitch | 2.5 mm | ~10.16 TPI (Threads Per Inch) |