People often talk about ID grinding and OD grinding as if each were one specific type of grinding. But both terms cover a wide range of concepts. Some initial definitions may help.
What is an Internal Grinding Machine?
“Internal grinding machine” is another term for an ID grinder. The process is also known as inside diameter grinding, inner diameter grinding, or bore grinding. Fixturing can be accomplished with chucks or a magnetic drive shoe, among other options. Applications include:
- Military tank components
- Hydraulic lash adjusters for automotive engines
- Rocker arm rollers
- Ball and roller bearings
What is an OD grinder?
An OD grinder does exactly what its name implies – it grinds the outer diameter of a cylindrical workpiece. Applications include:
- Transmission components
- Hydraulic components
- Axles
- Camshafts
- Crankshafts
What is a Cylindrical Grinder?
“Cylindrical grinder” is another term for a centered OD grinder, in which the workpiece is fixtured between two cone-shaped centers and a drive mechanism rotates the part. Even though our definition of cylindrical grinder is limited to centered grinding, there are many types of cylindrical grinders, like a machine with one spindle set up to grind multiple diameters.
What is a Universal Grinder?
A universal grinder performs ID OD grinding. These machines are set up to perform each set of operations separately, one after the other. Universal grinders are generally considered tool room machines, appropriate for low-volume parts. Individual ID grinders and OD grinders are preferred for high-volume projects.
It’s one thing to know the function of different types of grinders, but it’s another thing altogether to be able to create a grinding process that meets a customer’s specific needs.
How Do You Design an ID or OD Grinding Process?
Many critical elements are involved in developing the right grinding process for a customer. One of the first questions revolves around project capacity. A different solution is required for an application that grinds 10 pieces per year compared to one that handles thousands of parts per hour.
Material is another crucial consideration – hardened steel needs to be handled differently than, say, soft brass.
These decisions lead into selecting the type of fixturing for the workpiece, which affects rigidity and stiffness. The harder a part is held in place, the faster it can be ground.
Part tolerances also play a role in process design. Some sensitive applications can require ID tolerances of +/- 60 millionths of an inch, which demand a high level of precision.
The amount of automation vs. how much labor can be involved also must be considered. The process for the 10-piece-per-year project could easily accommodate hand feeding, while the project handling thousands of parts per hour requires a high level of automation, such as:
- Infeed conveyors
- Robotics
- Gantry-style loading and unloading systems
- Post-process gaging
Designing a grinding process is complicated and requires a well-developed understanding not only of grinding but of the part to be ground.
Thanks to our years of experience working with our customers, GCH Machinery has that understanding. Our goal is not to simply deliver a grinding system that meets a customer’s requirements but to help them increase productivity, reliability and accuracy, all while improving their bottom line.
Contact us today to take advantage of our expertise.