Sumitomo U101287 Solid Carbide Extra Length Drill Bit

Product Description

The SUMITOMO U101287 is a solid carbide extra length drill bit designed for demanding deep hole drilling applications. Part of the MDW-XHV series, it features a 0.25 inch (0.2500 inch decimal) diameter with a 140-degree drill point angle and a tapered web configuration for improved chip evacuation and hole entry stability. The DEX finish and through-coolant capability support extended tool life in high-heat cutting conditions. With a flute length of 3.937 inches and an overall length of 6.102 inches, this bit is built for reaching depth in tight or deep-bore setups. Licensed tradespeople and machining professionals who work in production or maintenance environments will find this drill suited for precision work in ferrous materials.

This drill bit is engineered primarily for deep hole drilling in ductile iron and hardened steel. The 12xD flute-to-diameter ratio allows it to reach depths that standard-length drills cannot achieve. The straight-cylindrical shank measures 0.315 inches in diameter and 2.047 inches in length, making it compatible with standard collet chucks and drill holders used in CNC machining centers and precision drilling equipment. It is well suited to both production-line and maintenance-repair applications where consistent hole geometry and diameter tolerance are critical.

Key Features

• Solid carbide construction for rigidity and wear resistance in ferrous materials
• DEX finish coating to reduce friction and extend tool life in high-heat cuts
• Through-coolant capability for effective chip flushing in deep hole operations
• 140-degree drill point angle optimized for entry stability and reduced thrust
• 12xD flute-to-diameter ratio supports deep hole drilling beyond standard reach
• Tapered web design improves chip evacuation and core strength

Compatibility

Designed for deep hole drilling in ductile iron and hardened steel workpieces. Part of the SUMITOMO MDW-XHV series. Intended for use with standard straight-cylindrical collet chucks or drill holders accepting a 0.315-inch shank diameter.

Installation Notes

Installation and use should be performed by qualified machinists or tooling technicians familiar with CNC or manual drilling equipment. Ensure the machine spindle and tool holder are fully powered down and locked out before loading or changing the bit. Confirm that the coolant-through circuit is active and delivering adequate flow before beginning deep hole cycles, as coolant interruption in deep bores can cause rapid tool failure. Do not exceed the maximum drilling depth of 4.055 inches for this bit designation.