Page 176 - Root Cause Failure Analysis

PROCESS ROLLS

Many types of process rolls are used in industrial applications. However, all share
common design, installation, and operating criteria, and this chapter provides a practi-
cal review of their design and application. In general, rolls can be divided into two
major classifications: working and conveying.

Working rolls change the product being processed through the production system.
Included in this classification are printing rolls, which transfer a pattern to the prod-
uct; corrugating rolls used to impart a profile to the product; bridle rolls, which pro-
vide torsional power to drive the product through the process; and work rolls used by
the metal-processing industry to change product thickness and shape.

Conveying rolls transport the product from one point to another. This type of roll
ranges from small-diameter, nondriven rolls used in simple conveyors to large-diame-
ter, driven rolls used to transport steel, paper, and a variety of other products through
continuous-process lines.

CONFIGURATION
All process rolls are composed of the following parts: body, face, neck, and bearing-
support shafts. Figure 13-1 illustrates a typical process roll used in continuous-pro-
cess lines.

Body
Depending on the specific application, the roll body may be constructed of a variety
of materials. Typically, cast iron or steel is used, but more exotic materials, such as
Monel, stainless steel, or bronze, may be used for certain applications.

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