There are so many different types of grinding as it relates to the manufacturing industry. So many… You’ve likely heard myriad terms associated with grinding in the daily conversations you have on the shop floor, in the boardroom, or out in the field with customers, vendors, and your competition. The advancement in grinding since the turn of the century has improved greatly and fits in to many different applications that exist throughout the manufacturing process – from inception on through finished product. Grinding is an essential part of the industry, and thus, we thought it would be helpful to put together a piece that discusses some of the more common applications/types that exist in today’s manufacturing landscape – while placing a strong focus on the finishing stage and putting the wraps on the task at hand.
Let’s start with the obvious question (in the event you’re new to the manufacturing world…)
What is “grinding”?
By-and-large, grinding is, at its core, a material removal process. It’s two main functions as it pertains to manufacturing operations is, most commonly, as a finishing process – giving a piece and/or part its final shape and texture. The other, is its function of sharpening cutting edges of applicable tools in the shop environment, be they mechanical or handheld.
Alright, now that we’ve got that out of the way, let’s get into the different types of grinding that you’re likely to be exposed to in the manufacturing industry.
Surface grinding
Surface grinding is the process used to produce flat, angular, and irregular surfaces. There exists four basic types of surface grinders in the industry which are:
- Horizontal spindle/reciprocating table
- Horizontal spindle/rotary table
- Vertical spindle/reciprocating table
- Vertical spindle/rotary table
Cylindrical grinding
Cylindrical grinding is, as the name suggests, the due process of grinding the outside surfaces of a cylinder which may be:
- Straight
- Tapered
- Or contoured
Cylindrical grinding operations resemble lathe-turning operations.
Centerless grinding
Centerless grinding machines eliminate the need to have center holes to stabilize the task at hand or the use of workholding devices. The process uses abrasive cutting to remove material from the workpiece. There are three main modes of centerless grinding which are:
- Through-feed
- End-feed
- In-feed
Internal grinding
Also known as “ID grinding,” Internal grinding is the process of removing material in a precise manner from an inside diameter of a cylindrical or conical workpiece – used to finish straight, tapered, or formed holes accurately.
Tool and cutter grinders
Grinding machines designed to sharpen:
- Milling cutters
- Reamers
- Taps
- Other machine tool cutters
Jig grinding
Developed to accurately locate and grind tapered or straight holes with precision.
Thread grinding machines
Developed to aide in dressing or truing the cutting periphery of the grinding wheel to produce a precise thread form on the manufactured part.
Creep-feed grinding
Historically, creep-feed grinding is utilized as an economical solution for specific applications, such as:
- In-grinding shaped punches
- Twist-drill flutes
- Various complex super alloy parts
Honing
Honing is an abrasive machining process which produces a precision surface on the manufactured metal workpiece by scrubbing an abrasive stone against the object along a controlled path to improve:
- Geometric form
- Surface texture
Why is all this important?
We should note that the above is in no way a complete list of the different modes of grinding/finishing. But it’s as solid start…
On the surface (no pun intended), it’s good to a have a well-rounded knowledge of that “goings on” in and around the shop. Grinding is often the last step of the manufacturing process prior to the actual shipping out of finished manufactured pieces and parts. It’s important to know the different options that are at your disposal and to partner yourself with a finishing shop that understands the very application you’re dealing with (if you’re not handling the finishing task internally). Efficiency is the name of the game in manufacturing – especially when the pieces and parts at hand are the working piece of a bigger picture/product.
A snag at the grinding/finishing phase is a major league mistake in the event that a wrong choice leads to the scrapping of an entire order. Think about the negative impact that’ll have on the bottom line and future impact of job acquisition. Grinding is no less important than the actual engineering phase. The finishing touch is imperative, so arm yourself with the knowledge of the myriad of different ways in which you can accomplish your unique need(s) so you don’t find yourself wishing you had at the outset. Because starting over is the type of grind you don’t want to find yourself participating in… That’ll send your job grinding to a halt. (See what we did there…)
