10.2 MACHINE TYPES

---

Typical categories of grinders include,

Surface

Cylindrical

Internal

Center

Centerless

Jig

10.2.1 Surface

Surface grinders have a few basic types,

- Horizontal Spindle with Reciprocating Table

- Horizontal Spindle with Rotary Table

- Vertical Spindle with Rotary Table

- Vertical Spindle with Reciprocating Table

10.2.2 Center

With centers parts are mounted so that they may rotate about fixed centers and then ground externally.

10.2.3 Centerless

Centerless grinding is popular as a high speed, low cost operation.

In this operation there is a grinding wheel and a governing wheel. The part sits between the wheels and is ground by the grinding wheel. The governing wheel acts to slow the rotation of the part so that it does not spin at the same speed as the grinding wheel and reduce the surface speed of the grinding operation.

If the part has a uniform cross section through feed grinding can be used. Otherwise infeed grinding will have to be used. For infeed grinding the parts are placed between the wheels, ground, and then pulled out. Through feed grinding has the parts move in a steady flow between the wheel.

10.2.4 Internal

Internal grinding is similar to other forms of rotational grinding, except that as the part rotates the internal features are ground by a smaller wheel.

Using a smaller wheel requires higher grinding speed which increases the challenge of this process.