The component is clean and dry — and still not ready for handover: a part that is too warm is of no use for a leak test.
Handing over components to the downstream process at a defined temperature
1 · The challenge
Why a clean component is not yet ready for handover
A component can be clean and dry and still not be processed further — namely when it leaves the system too warm. A part that is too warm is of no use for a leak test. The part temperature is thus not a by-product of the cleaning, but a requirement of its own on it.
The defined part temperature is demanded not by the parts cleaning system, but by the step after it. Whether testing, adhesive bonding, coating or painting follows the cleaning changes the requirement fundamentally — and where a leak test on the customer’s component follows, the temperature belongs to the conditions under which this test is meaningful at all.
The condition at the end of the cleaning is thus completely described by three quantities, not by one: residual contamination, residual moisture and temperature. A system can fulfill two of them and fail at the third — a component leaving the vacuum drying is dry, but not for that reason already cool.
Whoever considers the temperature only at the end of the system design has already fixed the process chain. It belongs in the same place as the residual contamination requirement: at the beginning.
2 · Engineering considerations
What we base the system design on
- 01
Downstream process
What happens to the component after cleaning determines the required part temperature — not the parts cleaning system. If a leak test on the component follows, the part has to reach it at a defined temperature; if adhesive bonding, coating or painting follows, that changes the requirement fundamentally, right down to the question of which water quality is needed. We therefore look not at the system, but at your production. - 02
Drying
How dry the component has to leave the system determines the effort at the end of the process chain — recirculated air, infrared drying, air blow-off or vacuum drying, designed to suit the project. With increased drying requirements and very high residual contamination requirements, vacuum drying comes into question — where conventional drying would leave residual moisture in bores and blind holes. Drying and cooling are two steps here, not one. - 03
Part geometry
Which component is cooled helps decide the cooling capacity: cooling capacity and target temperature are designed according to component, starting temperature, desired target temperature, air routing and the specific system design. A typical example is cooling from about 45 °C to about 22 °C — an example, not a general limit value. With components such as cylinder heads or gearbox parts, no temperature lower than about room temperature is often needed; if a process demands a different target temperature, the cooling capacity is designed accordingly. - 04
Cycle time
A cooling stage must not break the cycle of the production. Depending on the system design and the required capacity, cooling can take place within seconds — how long it takes in the specific case follows from starting and target temperature, component and air routing, not from a general statement. - 05
Part orientation
How the component lies in the system helps decide whether the cleaning medium drains off again and how much effort the subsequent drying takes. The component orientation is not simply adopted from the customer, but analyzed by us as part of the process design: for the respective component we determine the optimal position and orientation within the cleaning process — according to nozzle accessibility, spray shadow, drainage of the process medium, prerequisites for drying, defined positioning for the air blow-off and the requirements of the downstream process. There is no position that is better across the board; it is determined component- and process-specifically. - 06
Production concept and material flow
If the downstream test station already stands in the production, the actual task is not the system, but the interface to it: the component has to be handed over so that it can be tested there — in the required condition and in the cycle of the line. Whether material flow and conveying, robot handling or another handover achieves that is decided by the existing material flow.
3 · The process stages
Which process stages and concepts come into question
Cooling tunnel
If the downstream process demands a defined part temperature, a cooling tunnel can come into question as a stage of the process chain. We build and integrate it as a component of cleaning and process systems; depending on the system design and the required capacity, cooling can take place within seconds.
Drying and vacuum drying
Before the cooling stands the drying. With increased drying requirements, vacuum drying comes into question in particular — it is an option, not a method of its own, and whether it is necessary in the specific case is decided by the system design.
Spray-immersion cleaning systems
APOLLOWhere cleaning, rinsing and drying have to come together in one sequence, a spray-immersion cleaning system can make sense: the component passes through the stages in a fixed sequence instead of passing through them in separate processes.
Special-purpose systems
If no standard system design is enough because the process chain has to connect several stages up to the handover to an existing station, a special-purpose system comes into question — designed for the specific task instead of for a system type.
Material flow and conveying
The handover to the downstream process is a design matter of its own: material flow and conveying carries the component on in cycle and determines in which condition and at which point it leaves the system.
Robotics
If the component has to be transferred between stages or handed over to a test station in a defined position, robot handling comes into question — then it is not the conveying that guides the part, but a programmed sequence.
The principle
Why the temperature requirement does not dictate a system
A required part temperature says nothing about which machine type the system has. It says that the process chain needs a stage that produces this condition — where this stage sits, how it is designed and in which system concept it stands arises from component, production volume, cycle time, material flow and the downstream process. There is no rule “temperature requirement, therefore system Y”. What you see here is the consideration, not its result.
4 · What else to consider
What else has to be clarified beyond the cooling
- 01
The sequence in the process chain is fixed
The cooling stands not beside the drying, but after it. The chain reads: cleaning, rinsing, vacuum drying, cooling tunnel, defined part temperature — and only then the downstream process, for example a leak test of the customer’s component. Each stage presupposes that the previous one has reached its result. - 02
The interface can be the actual task
If the test station at the customer already stands, it is not part of the scope of supply — the task is then the interface to it. In a realized project for aluminum cylinder heads, the system reached from picking up the raw part to the handover to an existing test station; spray-immersion method, rinsing stage, vacuum drying and cooling tunnel were stages of this one sequence. - 03
There is no general target temperature
Cooling capacity and target temperature are results of the system design, not properties of a type of system. They depend on component, starting temperature, desired target temperature, air routing and the specific system design. A figure that applies to one component therefore does not apply to the next.
Questions and answers
Frequently asked questions about the part temperature
Does ITR build cooling tunnels itself?
To which temperature is a component cooled down?
Why is drying not enough when a test follows?
Who defines the required part temperature?
Direct contact
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93186 Pettendorf
Pettendorf bei Regensburg
Fax +49 (0) 9409-777 3607
Technically responsible for this page: Günther Zippel — International Sales & Technical Consulting