Movacolor dispensers

Plastic testing laboratories are looking for all kinds of quality and accuracy in dispensing technology. This is especially important for research related to the pharmaceutical and medical industries. Extruders manufactured by Zamak Mercator are adapted to work with Movacolor dispensers. The adaptation includes mechanical assembly and a program that facilitates the synchronization of the dosing system with the extruder. The description below contains basic information about the types of dispensers that can be used with our extruders. At the customer's request, we can use third-party dosing systems.

Gravimetric feeder vs. volumetric feeder

You might think that a gravimetric feeder and a volumetric feeder are very similar, and it makes sense that both systems were developed to dispense additives in-line with the desired output into the main feed stream of the extruderBoth dosing systems are equipped with a hopper, controller, stepper motor and dosing cylinder or screw feeder In terms of speed, Movacolor stepper motors range from 0.1 to 200 rpm, making it possible to set the rotation speed very precisely. quality.

Features and advantages of the gravimetric feeder

A gravimetric feeder, also known as a loss feeder, is a dosing system that doses based on weight and speed. A volumetric feeder does this based on volume and speed. using weight loss technology that measures the decreasing weight of the material as it is dispensed.
In a self-calibrating gravimetric feeder system, the stepper motor automatically changes its speed when it detects a change in material flow This eliminates the need for manual adjustments that are required when using a volumetric feeder Such a change in material flow can be caused by, among other things, adding new material or fluctuating material density This means that by using a gravimetric dosing device, you have full control over the quality of the final product. Thanks to the self-calibrating dosing system of the gravimetric dosing device, you will never be at risk of overdosing, thus automatically saving costs when using expensive additives. operated by a touchscreen controller.

Features and benefits of a volumetric feeder

A volumetric feeder is a dosing system that supplies the production system with a specific amount of material within a set time frame, based on the so-called volumetric principle. Unlike a gravimetric feeder, the dispensing speed of a volumetric feeder should be manually selected, which may vary depending on the type of input material, for example, masterbatch requires a different speed compared to dispensing liquid or powder input material For smaller production processes and companies looking to save on dispensing equipment, a volumetric feeder is preferred over a gravimetric feeder.This means that a gravimetric feeding system typically provides a higher return on investment (ROI) over the long term.

Advantages and disadvantages of gravimetric dispenser and volumetric dispenser

Gravimetric Feeder Benefits

• Self-adjustment / self-calibration
• 100% control over product quality
• Easy to use
• Monitoring and reporting options
• More savings on expensive additives
• Density fluctuations do not affect the result
• Insensitive to material accumulation
• Automatic detection of a material supply interruption
• Accurate dispensing cylinder
• Stepper motor speed from 0.1 to 200 rpm

Inconveniences

• Relatively more expensive than volumetric feeder, but short return on investment.

Volumetric Feeder Benefits

• Relatively cheap dosing system
• Accurate dispensing cylinder
• Stepper motor speed from 0.1 to 200 rpm

Inconveniences

• Manual recalibration required
• Limited control over product quality
• No monitoring and reporting options
• Density fluctuations cannot be automatically compensated for
• Sensitive to material build-up
• No automatic material supply interruption detection

When should you choose a gravimetric feeder and when is it best to use a volumetric feeder?
To choose wisely between gravimetric and volumetric dispensers, it is important to know your budget and purpose As mentioned earlier, both Movacolor dispensing systems have a stepper motor and a unique dispensing cylinder. However, volumetric dispensing systems are relatively inexpensive to acquire in the short term, resulting in little immediate investment Gravimetric dosing systems, on the other hand, are more expensive to purchase, but in the long run you will save on costs thanks to significantly less consumption of expensive additives.

Optometric dosing systems for small, precise end products

Optometric dispensing technology has been specifically developed by Movacolor for the production of ultra-small precision end products on micro injection molding machines and micro extruders Due to the tight tolerances of high precision end products and the limited mixing capabilities of these small injection molding machines and extruders, in most cases these high precision applications are mixed material These specially manufactured pre-mixes are expensive due to the small production batch. As a result, Movacolor engineers have developed optometric dispensing technology. This high-precision, patented dispensing system enables significant cost savings by using standard virgin material and masterbatch or dosing additives in micro injection molding machines and micro extruders.

Optometric dosing technology versus gravimetric dosing technology

Compared to optometric dosing technology, gravimetric dosing has its limitations Ultra-low dose weight requires extremely low doses with 100% repeatability and high dose-to-dose accuracy When you dispense extremely low mass pellets with a gravimetric feeder, there is a problem with the response time of the control systems and the mechanics of the dispenser.
The problem of dosing very small doses can be solved with an optometric dosing system because with the unique, patented optometric dosing system you will be able to dispense ultra-precisely, granule by granule.

Optometric dosing technology how it works

The air creates a vacuum behind the disc with small holes. The disc rotates and collects the masterbatch granules.Optical sensor detects masterbatch pellets when sensor signal is blocked With this technique, the software is able to count the amount of masterbatch pellets dispensed pellet by pellet.

Fluid dispensing system

Liquid dyeing can be a difficult operation It's all about reliable dispensing, often at extremely low doses Fluctuating fluid viscosity and spill-free handling are the main issues Movacolor has developed a modular liquid dispensing system with one universal motor, two types This gives you the opportunity to compose the optimal configuration.

Peristaltic pump
The peristaltic pump is used in processes with frequent color changes. Available as a gravimetric and volumetric dosing system.
Benefits:

• Easy color change.
• The gravimetric system ensures consistent performance.
• Low dosing doses.
• Easy cleaning.

Disadvantages:

• Limited pump hose life.
• Limited pressure rise.
• In volumetric mode, performance depends on viscosity

A peristaltic pump combined with a gravimetric scale is the perfect combination for color change Gravimetric control automatically compensates for inaccuracies in the peristaltic pump The performance of a peristaltic pump is highly dependent on the viscosity of the liquid, the type of pump hose used and the age and wear of the pump hose.

Gear pump

For long runs, we recommend using a gear pumpThe gear pump liquid dispensing system is available as a gravimetric and volumetric dispensing system.
Benefits:

• Long service life.
• It can generate pressure up to 10 bar.
• Performance independent of viscosity.
• Easy replacement of pumps.
• Extremely low dosing rates (gear pump).
• High dispensing rates (single pump).

Disadvantages:

• The system should never run dry.
• Difficult to clean.

The description of the dispensers was prepared on the basis of materials from the manufacturer's website with respect to all rights. https://www.movacolor.com/