2. Characteristics of the Process Industry
Process industries are defined in the APICS Dictionary (1987) as:
"Process industries are businesses that add value to materials by mixing, separating, forming or
chemical reactions. Processes may be either continuous or batch and usually require rigid
process control and high capital investment"
Typical examples of process industries include the chemical industry, petroleum industry, paper
manufacturing and the food and beverages branch. The relative position of the process industries
is put in perspective in the Product-Process matrix developed by Hayes and Wheelwright (1979),
as is shown in figure 1.
CUSTOM
PRODUCT
COMMODITY
LOW VOLUME
HIGH VOLUME
DIFFERENTIATED
DIFFERENTIATED
JOB
SHOP
AEROSPACE
INDUSTRIAL MACHINERY
APPAREL
MACHINE TOOLS
P
R
O
C
E
S
S
DRUGS
SPECIALTY
CHEMICALS
FLOW
SHOP
ELECTRICALS
ELECTRONICS
AUTOMOBILE
TIRE & RUBBER
STEEL PRODUCTS
MAJOR
CHEMICALS
PAPER
CONTAINERS
BREWERS λ,,
OIL
STEEL
Figure 1: Product-Process matrix
Table 1 lists the major differences between the process industries and the discrete industry in the
relation to the market, the production process, the quality of the products and processes, and the
planning and control function (see Koene (1988), Taylor et. al. (1981), Vollman et. al. (1988)).
As to the difference in automation between discrete industries and process industries, one can
observe that in the process industries the production process itself is highly automated, while in
the discrete industry more emphasis is put on automating the planning and control system.
3. Maintenance Planning
The importance of adequate planning in the maintenance function is emphasized by Gits (1994):
- Increased mechanization and automation require that a lot of maintenance has to be done. It
has been found uneconomical to retain large maintenance staffs for emergencies that can be
avoided through planning and systematized inspection.