Machining Rolling Mill Roll with CBN

White Iron Roll Machining

Application Example:

Component: Rolling Mill Roll (1 metre diameter x 3 metre long)

MachineTool: Craven Centre Lathe

Material: Chilled Cast Iron ( 55 Hrc)

Operation: Turning

Depth of Cut: 2 mm (0.08")

Insert: RNMN 120300T DR-100

Surface Speed: 100 m/min (330 ft/min) cutting without coolant

Feed Rate: 0.2 mm/rev (0.008"/rev)

Surface Finish: N/A

Tool Life: Average 40 minutes contact

Comments: Semi-finishing for grinder � machine not powerful enough for bigger cuts or feed rates

DR-100 has a high CBN content, 99%, and is supplied as solid I.S.O format indexable inserts for top clamp tool holders. PCBN cutting tools machine hardened steels with apparent ease because, using relatively high

surface speeds, heat is generated at the point of cutting so the PCBN tool cuts locally softened material.

For more information on machining with CBN Inserts
please visit David Richards Engineering UK or
David Richards Engineering US

Using Coolant - CBN Inserts - Interrupted Cutting

Although most of the heat essential for efficient cutting exits with the chip, any increase in the temperature of the component will make accurate measuring difficult. Coolant can be used to reduce this effect.

Coolant can be used to drive away any swarf which might interfere with the cutting edge, particularly in boring operations. Coolant can help reduce vibration, especially where rigidity is limited.

Where interrupted cutting with CBN inserts occurs, coolant should not be used as this will thermally shock the CBN tool as it comes out of the cut, resulting in premature failure. Although interrupted cutting with coolant will never improve tool life, it is possible to use coolant machining hardened steel with DR-450 CBN inserts and coolant can be used when machining cast iron with CBN, that is not hardened, under all conditions.

For more information on machining with CBN Inserts
please visit David Richards Engineering UK or
David Richards Engineering US

Cnc Milling: a Versatile Process

Author: George Ure

Computer Numerical Control (CNC) Milling is a common type of automated machining process. These machines are specially used for drilling, facing, and turning functions. Their classification is based on the number of axes they have. These axes are labeled as x and y for the two horizontal directions while z is for vertical movement. CNC milling is a cutting process that is used to remove metal or plastic from a block of stock material by the rotating action of the tool. The tool is moved in three (or more) directions to get the desired cut of the material.

CNC Milling machines have been programmed with the help of a set of commands called G-codes. These codes are special CNC functions in alphanumeric format.

The cutting tool is usually rotated along the axis, which is perpendicular to the table where the material to be cut is placed. There are different cutter shapes (called milling bits) such as round (ball end), square, and angled.

Advantages of CNC Milling

A large variety of 2D and 3D shapes are possible. Complex shapes from rod, block, or sheet material can be created and is cost effective for short runs.

Specifications for CNC Milling

• Rigid materials such as metals and hard plastics are used.

• Alternative machines for 2D sheet shapes that include Laser Cut, Turret Punch and fixed punch are used.

• CNC Milling requires software program tooling or work holding jigs.

• To contain costs avoid large variations in work piece height and avoid thin walls.


The CNC Machining centers are computer controlled vertical mills which can move the spindle along the Z-axis. When the machine is used in combination with conical tools or a ball nose cutter it improves the milling precision without affecting the speed thus providing an economical substitute to flat surface job that requires hand engraving.

During the milling process pressure is applied to the material therefore it is better to avoid weak shapes, long thin shapes, or ones with thin walls. CNC milling offers a cut surface that has a visible pattern due to the rotation and movement of the cutter.

eMachineShop offers you information about a vast number of products and machines and CNC Milling machine is one of them. A unique online CMC provider allows you to design and even order custom CNC machined parts. Visit the site www.eMachineShop.com to get details about these and other services. While you’re there, don’t forget to download the company’s free 3D CAD software which makes designing CNC milled parts a snap!

Article Source: http://www.articlesbase.com/business-articles/cnc-milling-a-versatile-process-320816.html

About the Author:
George is a well known author who writes on the topics related with CNC Milling , waterjet cutting and Free CAD Software for the site www.emachineshop.com.

Machining Engine Gear Example

Welcome to a new section of carbideinserts.blogspot.com. Our focus with these blog posts will be to provide application examples with insert type, speeds and feeds, to hopefully give you a baseline and to help you with your own machining applications. We will add these machining tips on a regular basis, so check back often!

Component Description: Engine Gear
Material: Low Carbon (0.2% C) Cr-Mo Alloy Steel
Cutting Paremeters: SFM=984
Feed=.010ipr
DOC=.051"
Wet cutting. Face & External Turning, continuous cut.
Recommended insert: CNMG 432ML TT5100

PCD Insert Machining Dont's #1

PCD inserts are not recommended for the machining of Iron, Cobalt, or Nickel alloys. In the presence of these metals and the heat and pressure created by cutting, diamond is encouraged to revert to the metastable carbon form: graphite. It is possible to use PCD inserts to machine some stainless steels and other highly alloyed materials, which have the iron, cobalt or nickel tied up in a non-reactive state. Even so, these materials should be machined at low cutting speeds and feeds with coolant to reduce any heat generated.

What is PCD (Polycrystalline Diamond)?