Industrial Paint Shop Plants

A complete paint shop is not a row of independent machines placed side by side. Stage times, line speed, oven length and building area are interdependent variables; change one and the others change too. The plant is therefore configured backwards from the part and the target capacity.

How the process works

Design always starts with two questions: which part and how many per hour. Part geometry determines the surface treatment method (dip or spray), while the capacity target sets the line speed. Once line speed is fixed, booth and oven lengths — and therefore the building area required — are largely determined as well.

Energy infrastructure comes next. Installed electrical power, natural gas capacity and the water/wastewater connection are the real constraint in most projects. These three items usually determine the gap between the theoretically most efficient plant and the plant that can actually be built on site.

Concentrating responsibility in one place eliminates the work that gets lost at interfaces. When the booth comes from one company, the oven from another and the conveyor from a third, the boundary of responsibility becomes a matter of debate as soon as a problem arises — and the performance guarantee is split as well.

The seven-step delivery process

• Technical survey — part geometry, capacity target and energy infrastructure are measured on site
• Process design — the number of stages, cycle time and temperature window are calculated
• Concept and budget — layout plan, equipment list and investment budget are presented
• Detailed engineering — mechanical, electrical and automation designs are submitted for approval
• Manufacturing and inspection — workshop manufacturing and pre-assembly tests are completed
• Site installation — installation and connections are carried out under health and safety supervision
• Commissioning — performance testing, training, documentation and acceptance

Technical framework

The figures are typical operating ranges for the sector. Every line is recalculated according to part geometry, target capacity, paint system and customer specification.

Frequently overlooked points in design

• Planning the building and the line at the same time: Column grids, clear height and floor load capacity constrain the line layout. Line design must begin before the building design is frozen.
• Capacity increase scenario: If line speed is expected to rise later, oven and booth lengths should be chosen accordingly; extending them afterwards usually runs into the building limits.
• Performance acceptance criteria: What will be measured and by what method must be set out in writing at the contract stage. “Good coating quality” is not a measurable acceptance criterion.

Related topics

• Surface Treatment and Cataphoresis
• Paint Booths
• Industrial Ovens
• Conveyor Lines