There are a lot of factors that go into the creation of a custom parts basket for a given manufacturing process. From selecting the right diameter of wire for a basket, to picking the right type of metal for the frame, to picking the right coating, custom basket design engineers have to consider many different factors.
For many custom basket designs, picking the right coating can greatly improve the longevity and functionality of the basket.
However, there are many different types of coatings available to use for baskets. Each type of basket coating has different properties for hardness, temperature resistance, chemical resistance, porousness, etc.
These unique physical properties make some coating materials more suitable for certain jobs than others. Which coating would be the best for your next project?
The answer is: it depends on the project!
When choosing a coating, the first thing to keep in mind is the process or processes you’re going to be putting that coating through.
So, which coating would be the best for your next production project? Here are a few recommendations for various applications:
Coatings for Common Parts Washing Applications
Parts washing is one of the most common finishing processes employed by manufacturers to get their manufactured goods ready for shipping. Many of these processes use mild to moderate-strength chemicals at temperatures well below 300 degrees Fahrenheit.
In these situations, the most common use of a coating is to prevent or limit the exposure of a basket’s frame to the chemicals used in the wash process so as to reduce or eliminate corrosion.
For these applications, the following coatings are generally considered optimal:
- Polyvinylchloride, or PVC, is a popular coating that can be applied via dipping or fluid bed processes. PVC is soft, chemically-resistant, and capable of being applied in very thick coats.
- Polyester TGIC Powder Coat. Polyester triglycidyl isocyanurate (TGIC) coatings are highly resistant to solvents, salt spray, and ultraviolet radiation, helping to protect baskets from corrosion. Unlike PVC, however, Polyester TGIC has a high pencil hardness, making it resistante to marring, chipping, and scratching.
PVC is great overall for no-scratch parts washing applications, as the softer material will absorb impacts rather than redirecting the force into the parts your basket holds. Polyester might be more suitable for hard-use applications where hard edges might dig into the basket’s frame or the basket may be exposed to direct sunlight.
Coatings for High-Temperature Applications
Most polymers cannot survive exposure to temperatures in excess of 300 degrees Fahrenheit for an extended period of time. This is why, in most cases, polymer coatings aren’t used for high-temperature applications. Even heat-resistant polymers can’t rival most steel alloys for temperature resistance.
However, if a coating is necessary for a high-temperature application below 500 degrees Fahrenheit, then your best options include:
- PFA Teflon®. Chemours’ Teflon® brand name covers a range of different coating materials. Perfluoroalkoxy Teflonâ, or PFA, can be used in environments of up to 500 degrees Fahrenheit and boasts incredible chemical resistance. Plus, it can be applied in thick coatings.
- PTFE Teflon®. Another Chemours-brand material, polytetrafluoroethylene (PTFE) is a non-stick coating with a high hardness and a temperature resistance of 500 degrees Fahrenheit.
While no match for the temperature resistance of many steel alloys, these polymers do have their uses in applications with high temperatures not in excess of 500 °F.
For example, PFA is ideal for sterilization processes that involve both oven-like temperatures and corrosive chemicals to render products free of bacteriological contaminants. Here, the combination of chemical and temperature resistance help ensure that the coating will last through repeated use, prolonging basket life.
PTFE, on the other hand, is slightly less useful for protecting baskets from chemicals, as the coating tends to be very porous. Rather, this coating is more frequently used for its non-stick properties, helping keep debris or sludge from sticking to the basket. This might be useful for vapor degreasing when applied to baskets that are already corrosion-resistant, but need to stop runoff from sticking.
Many companies in the food and pharmaceutical industries require custom containers that are sterile to prevent the spread of contagions that can cause illness.
Here, many companies turn to antimicrobial coatings that can kill germs or prevent them from spreading. There are a lot of different antimicrobial coatings; too many to list them all here. These coatings fall into two broad categories: active and passive.
Passive coatings go onto a surface and will continue to work until they are damaged or scraped off. Active coatings, on the other hand, have some form of active ingredient in them that is consumed over time as the container is used.
For example, silver ion-based coatings use silver particles as an active ingredient. When microbes come into contact with the silver particles, the silver attaches to the DNA of the microbe, causing damage. This can kill the microbe or keep it from multiplying, preventing the spread of bacteria.
The advantage with passive coatings is that they tend to last a lot longer than active coatings. However, active coatings tend to be more effective at controlling bacteria.
These are just a few examples of different applications that could benefit from the use of specialized coatings, and the different coatings you can use. For more information about which coating is the best for your particular needs, contact an experienced mechanical engineer today!