2K Meter-Mix-Dispensing requires a good understanding of the properties of the materials and studying the different process requirements. Whether it’s dotting, line, or potting, meter-mix machines are complex and highly customized to meet the user’s needs.

Following are the four commonly used metering methods for meter-mix-dispense applications.

Piston Displacement

The piston displacement method works by attaching a piston to the end of a rod, with which material is pushed out positively from the cylinder. The internal diameters of the 2 cylinders determine the mixing ratio and dispensing amount for each dispensing stroke. The dispensing speed and amount can be set by the magnitude and speed of the piston movement during the dispensing cycle.

Positive Rod Displacement

This method uses a solid rod to displace fluid as it moves in and out of a cylinder into which material is fed. Metering is accurate with good repeatability as the rod displaces a fixed amount for each stroke. The ratio can be changed by simply replacing one of the rods with a different diameter.

Progressive Cavity Pump

The Progressive Cavity Pump consists of a rotor and stator that forms a perfectly sealed metering chamber within a housing. It dispenses continuously with a rotary displacement action based on the screw pump principle.

Precision Gear Metering

This method uses the gear size and rotation speed to determine the ratio and dispensing amount. As such, these factors can be changed very easily by changing the rotation speed of the gear pumps. The precision gear metering system provides a continuous flow of material without the need to reload. We have a video demonstration of this gear metering system, please click here.

It is less suitable for materials with abrasive fillers as it will require more maintenance due to higher wear and tear of the gears.

Amongst the above 4 metering methods, if your material contains fillers, we would recommend positive rod displacement method because of the advantages mentioned below:

1. Ease of Bleeding of Bubbles: As material goes in from the bottom of the cylinder and goes out from the top, existing bubbles in the system can be bled easily via a venting outlet at the top of the cylinder.
2. Ease of Changing of Mixing Ratio: Changing rod size to cater to change of mixing ratio can be achieved quickly and at a low cost.

Let our expert engineers help you with your application and provide you with the best solution for your 2-component material dispensing processes.

TechnoDigm™ possesses over two decades of experience with fluid dispensing and UV curing technologies, always ready to help you.