Testing Standards for Coatings
Which coatings performance testing should be conducted to insure industry quality standards are met?
Q. We manufacture a wide range of metal and wood furniture. Can you help us identify any types of coatings performance testing that we should be conducting to insure we are meeting industry quality standards?—D.H.
A. Product performance and liability are major issues for manufacturers today. Adopting proper coating performance testing using standards such as ASTM (American Society for Testing & Materials) will help to insure you are meeting the performance and quality challenges related to industrial coatings issues. There is a wide range of standards for finish performance, and consumers over the years have helped form what these should be.
There are several things to consider as you set out to do ASTM testing. Testing equipment can in some cases be rather expensive and may require proper training to operate correctly. You may want to weigh purchasing equipment and conducting the testing internally verses sending it to an outside laboratory for evaluation. You may also find that your coating supplier can provide some of these services for you as well. If you belong to a particular manufacturing association, it may be able to guide you to a set of industry-related standards. I have compiled a short list of a few common ASTM standards that may be of help to you in evaluating what you may want to test for:
• ASTM D1308 Chemical Resistance is a visual test to determine the affects of various household chemicals.
• ASTM D3359 Cross Hatch is a common test that determines how well a coating will adhere to the surface after the coating has been scratched and pulled off with tape.
• ASTM D3363 Pencil Hardness will determine how hard the coating surface is.
• ASTM 4060 Abrasion Resistance will determine how well the surface holds up to abrasion, simulating a lifetime of service.
• ASTM D 2794 Impact Resistance will determine how well a finish will adhere and hold up to a sudden impact.
• ASTM D 2091 Print Resistance of Lacquers will help determine how well a finish will hold up when heavy items are placed on it for extended periods of time. Will it leave an imprint once the item has been removed?
• ASTM D 523 Specular Gloss will help ensure you are shipping the same sheen level with every order.
Pardon the pun, but I have not even begun to scratch the surface as to the myriad of ASTM physical property tests that can be conducted on coated surfaces. There are tests for the affects of boiling water, hot/cold cycles, UV exposure, color variance—on and on you can go. If you do not already have a quality assurance department, I would recommend that your organization form one. Then, this internal department can identify what ASTM testing to adopt and build into manufacturing quality performance standards. This will help ensure that your customer is getting consistently manufactured products.
Once you have adopted the ASTM standards for coating performance and implemented them into the quality standard, the next challenge will be to establish accountability from the supplier all the way to your employees. Typically, once everyone sees the benefits of testing and quality policies, you will begin to see favorable results.
Choosing the right conveyor system, coating technology, and ancillary equipment.
Preventing solvent pop on an industrial paint line...
Simply heating up the substrate does not cure the coating. There are many variables to consider when choosing the best cure oven for your application...