Casey Bickhardt, president & CEO, GEMCO

Manufacturing has changed drastically, and speed to market has never been more important than it has in 2020. Specifically additive manufacturing and the 3D printing industry have been viewed as transformative technology that is fueling market growth. Therefore, for this sector of manufacturing, it is key to be supplied with the right powder mixing and drying equipment for rapid prototyping to keep up with supply and demand.     Still unsure if you need a vacuum tumble dryer? Here are our top three reasons how your production can benefit from this powder drying technology. 

1. Temperature Sensitivity for Volatile Materials

Materials such as aluminum, cobalt-chrome, stainless steel, precious metals, plastics, and copper or nickel alloys are prime candidates for a vacuum tumble dryer because of their sensitive and unstable particle properties. Vacuum tumble dryers are known for their gentle approach and heat sensitivity. A vacuum dryer has the ability to lower temperature and atmospheric pressure to remove solvents from damp or wet material without the issue of overheating the product. The walls of the vessel are heated to carefully pull these unwanted liquids from the material as each particle moves six times per one revolution. This drying process can be broken down into three key phases:

1. Heat Up Phase
2. Constant Rate Drying Phase
3. Falling Rate Drying Phase

During the “heat up phase” the vessel is brought to a boiling point in preparation for the wet powder. After reaching the desired temperature, you are then in the “constant rate drying phase.” This is considered the “easy” part of drying mainly because it involves pulling the bulk of the water solvents off the powders’ surface. The final stage of the drying process is the “falling rate drying phase” where heat is pushed into the material to remove minute water particles trapped inside the product. Carefully, the vacuum dryer successfully completes each stage without damaging your product.

Additionally, this removal process operates in a closed system. What happens in the dryer stays in the dryer, which keeps the environment and operators safe from any potential harmful materials. Since 3D printing often involves working with nickel and/or potentially dangerous material, containing these elements are necessary for overall safety. Smelling chemicals or seeing burnt material is a tell-tale sign you need a vacuum dryer.

2. Increases Flowability

By increasing powder flowability you can prevent clogging, which is a common issue when working with 3D metallic, ceramic, and plastic powders. Special attention, quality manufacturing equipment, and techniques are key if you want to speed up the overall process of producing parts for 3D printing.

A proven method to increase flowability is by using a vacuum tumble dryer to pull surface water or moisture from the powders. By eliminating this resistance caused by the moisture, material can run better and smoother.

A more creative method done by a vacuum dryer focuses on eliminating electric charge by heating certain metals. This better aligns the particles on an atomic level making them more linear and ultimately allowing the powder to flow effortlessly.

3. A Controlled Process for Repeatable Results

Being able to control your drying process is a top priority simply because this ensures your batches are predictable and repeatable. Incorporating “smart” dryer technology, there is no more guesswork in your production. Vacuum tumble dryers have the ability to control its temperature, atmospheric pressure, and powder flow. This is achieved by sensors placed directly in the unit.

These sensors are situated in the best spot to provide a true and constant reading of temperature and pressure. These readings are then displayed as a graph to break down the data so you can reference this chart later. This allows you to compare your drying data and have the confidence that your batches will be consistent.

The vacuum dryer’s versatile and durable design guarantees outstanding service life and low maintenance cost. This machine is also scalable, which will fit nearly any production. Lot sizes range from 10 to 1,800 kg with full traceability of the different batches. Overall, vacuum tumble dryers can improve the quality of batches and manufacturing productivity—especially for industries involving plastic, metal, or resin based powders.

Casey Bickhardt is president & CEO, GEMCO (Middlesex, NJ). For more information, call 800-654-3626 or visit www.okgemco.com.