Industrial production can be divided roughly into two main types of production: process and discrete production. This division can be further refined by looking into the produced volume and the variety of products being produced. In the following picture the different types of production processes according to these dimensions are presented with some examples.
This model, originally introduced by Hayes and Wheelwright, depicts different production types on the diagonal axis according to the amount of variants and the production volume:
In project production there is in practice an endless amount of different variants that can be produced since every product produced can be an individual project, but the produced amounts are small. On the other extreme, the continuous process production is characterized by high production volumes but small amount of different product variants.
The three types in the middle, job shop, batch production and repetitive production (or mass production) are in practice usually different forms of discrete production.
Job shop is based typically on flexible resources which can produce very different product variants. These resources are often organized according to the production task (so called functional layout where similar tasks are grouped together such as welding or assembly). There may be often order-related product engineering for different product variants. However, there is still certain amount of repeatability, which differentiates job shop from a project.
In batch production products are produced in batches. A product is produced more than once, but not continuously. The production can be organized for example in production cells or into flow production.
In repetitive production products are typically produced in production lines, where each work station carries out precisely predefined tasks. In repetitive production the precise organization of work brings cost efficiency. Products may as such have many variants, like in a modern automotive factory, but the variants are planned so that their impact to manufacturing is minimized. The variance in production is low in the sense that with line production a fully different product would most likely require a new production line.
Differences between the production types
The production types differ from each other in several respects. Generalizing roughly, on the upper left hand corner of the diagonal the main focus on flexibility and ability to react, on the lower right hand corner in cost efficiency. This can be seen for example in the machinery and equipment: in project and job shop the equipment tends to be general purpose equipment with high requirements for flexibility, whereas in repetitive and continuous process the equipment is often special purpose equipment, designated for producing one type of product, and the flexibility for product changes tends to be lower.
The production types also have an impact to production planning and control. While for example in the project production the main focus is on the schedule of the project with its critical path, in a repetitive line production the key question is the best sequence for the products to be produced, and coordinating the material flow accordingly. Also what kind of layout (i.e. physical arrangement of resources) is good depends on the production type. There may be differences in the skills needs of the operators: in project or job shop there is more likely a need for the operators to be able to carry out many different tasks, whereas in repetitive production the work is divided into smaller tasks, which need to be mastered fast and precisely.
In practice the division between the different production types is not absolute and exact, the types should rather be seen as archetypes. Same product can be produced in different types: for example an equipment manufacturer could have a production line for high volume products and a job shop for small volume customized products. Or the different steps in the overall production process may involve different production types: for example parts production is batch production and the final assembly a repetitive process.
In addition to the volume-variance –division the different production types can be depicted according to the material flow shape: how many different items are there along the way in the production. Thus production can be divergent / V-type (for example raw material copper is drawn into many different sizes of tubes) or convergent / A-type (one machine is assembled from several different components). Also other forms exist. For example the production of modular products would be divergent-convergent: from a large amount of raw materials and components a limited amount of modules are produced, and through combining these modules in different combinations one can create a high amount of different variants.
The production types can be classified also depending on the way the production is managed, especially according to the OPP (Order penetration point). These different forms are discussed in their own pages.