Accurate Dosing Of Release Agent

• Flow meters and controllers can be used to create very accurate liquid dosing
• Many manufacturers, such as in the automotive industry, use dosing processes to create thin-layered materials such as polyurethane leather, which is used for covering dashboards, steering wheels, and more
• Using a flow meter and controller for liquid or gas dosing systems improves process control, thereby reducing maintenance and downtime, while increasing accuracy and efficiency

Have you ever seen cars with a nice leather-looking dashboard? One of our customers in the automotive industry manufacturers these ‘skins’ that look like leather. These skins are produced by spraying liquid – colored polyurethane – into moulds. Having a highly accurate dosing system allows continuous production of high quality polyurethane leather, while reducing costs and downtime.

Ultra Low Flow Chemical Processes Require Accurate Dosing

To allow an easy skin release from the mould, a release agent must be applied onto the mould surface. The amount of release agent is essential in this respect and must be perfectly dosed as it determines the quality, look, and feel of the product. The skin will remain adhered to the mould when too little release agent is applied. Whereas too much agent will give glossy spots on the skin.

The customer asked for support in designing a dosing solution that can dose the release agent very accurately, resulting in less production loss. Besides that, the offered dosing solution reduced the downtime necessary for calibration and maintenance significantly.

Using a Bronkhorst Flow Meter for Accurate Dosing Performance

• Accurate dosing of release agent
• Improved process control
• Visualization and alarm settings
• Process data management

Why Integrate a Flow Meter into a Dosing Pump System

In the past, some problems occurred with supplying external release agent using mechanical solutions, such as pressure regulators and gear pumps. These old solutions were not suitable for low flow use and were unstable at low viscosities. Moreover, their maintenance and calibration costs were high. Also, the process had to be adjusted continuously by the operator. A new solution to accurately dose external release agent has been developed to help overcome these problems.

Compact Flow Controller Designed for Manufacturing Processes

A Bronkhorst Coriolis mass flow controller (series mini CORI-FLOW M14) combined with C5I valve accurately supplies external release agent to the nickel mould surface. These compact devices are mounted next to the robot arm that sprays the agent by means of a spray nozzle. The robot arm moves along the surface of the mould, where the required amount of agent is sprayed homogeneously. This setup can be used for both water-based as well as solvent-based release agents.

Using a flow meter and controller results in a stable flow, even with low flows of less than 5 grams per minute. Compared to other dosing methods, the overall release agent application process stability improves. This means there is consistent, quality color and gloss of the polyurethane leather car dashboard skin. Also, reproducibility is high, as the linear flow curves have the same output for all installations. After change of set-point, the response time is excellent.

Due to the compactness of the Coriolis mass flow controller with C5I valve from Bronkhorst, they are easy to install and integrate into existing installations. Data can be transferred from the flow controller by means of RS232, Profibus, and analog outputs. Control and monitoring allow easy visualization and data capturing.

This solution meets increased quality demands by OEMs, as real mass flows are being measured and controlled. The downtime necessary for calibration and maintenance is largely reduced.

Widely Used, Accurate Dosing System with Custom Engineering Support

This flow instrumentation system provides unequalled results compared to traditional dosing methods. Currently, there are about 100 combinations of flow controller with C5I valve being used at automotive factories worldwide. Ask our engineers for assistance to design a new dosing system for your process or integrate improve flow control into your existing equipment.