Sandvik Coromant Coated Carbide Milling Insert, GC3220 Grade, MTCVD Coated, Square Shape, KL Chip Breaker, 12 Insert Size, 0.156" Thickness, 0.079" Corner Radius (Pack Of 10)

The Sandvik Coromant CoroMill R290.90 GC3220 right-hand carbide indexable milling insert has a square shape, is available with a KM or KH chipbreaker, and provides good wear resistance without limiting shock resistance for medium or heavy machining of gray cast iron in average-to-good machining conditions. A combination of carbide and a thin multilayer coating of titanium carbon nitride (TiCN), aluminum oxide (AI203), and titanium nitride (TiN) applied through medium temperature chemical vapor deposition (MTCVD) performs well at medium to high cutting speeds, mainly without coolant. MTCVD coatings are deposited at lower temperatures than CVD coatings, resulting in the appearance of few or no cracks in the coating, and providing improved toughness and smoothness compared to CVD coatings.

This positive insert is used with the CoroMill 290, a screw-style insert holding system for general-purpose square shoulder milling and face milling of thin-walled components. The insert is available with a KM chipbreaker for medium machining, or a KH chipbreaker for heavy machining. Edge performance is rated as M for highest security. The square shape provides strong cutting edges. The insert has a hole in the center, four cutting edges, and an 18-degree clearance angle.

Milling inserts are coded according to their specific cutting and application capability (e.g., R290.90-12 T3 20 M-KH). Each section of the code represents details of the insert: hand, compatible toolholder series, size, corner radius, edge performance, and chipbreaker style. Insert shapes and sizes may have different inscribed circle (iC) measurements, which relate to ranges of cutting depths, speeds, lead angles, and feed rates. The inscribed circle is the largest circle that can be drawn within the edges of the insert shape. Generally, as the insert size and the iC become larger, the maximum cutting depth increases. Cutting depth influences the metal removal rate, the number of cuts, chip evacuation efficiency, and power required when using the insert. Indexable inserts are small cutting tools designed to remove material in external and internal cutting applications such as turning, milling, drilling, and grooving. They are held by an insert holder, have multiple cutting edges, and can be rotated when one edge wears down. Multiple inserts can accomplish a variety of cuts in one operation. An insert is either positive or negative, which refers to the rake or clearance angle at which the insert removes material.

Sandvik Coromant produces tools for turning, milling, and drilling. Headquartered in Sweden and represented in 130 countries, the company manufactures tools used throughout the metalworking field, including the automotive and aerospace, die and mold, and general engineering industries.

These inserts are used with the Sandvik Coromant CoroMill 290, a screw-style insert holding system used for general-purpose square shoulder milling and face milling of thin-walled components. The cutting force does not expose the surface being machined to high axial pressure, which is advantageous for workpieces with a weak structure or thin walls, or for unstable fixtures. When used with the CoroMill 290, this insert has a 0-degree lead angle and 90-degree entering angle. It is used to mill true 90-degree corners and can produce an excellent surface finish.