At Pecora, we truly believe that no matter that size of the project, one of the most important aspects of the job is quality control through application testing. Proper testing methods ensure product success, structural endurance, and most importantly, a happy customer. This week we explore Pecora-Deck field inspection and test procedure: Quantitative Test Method – ASTM D4541 Pull Off Adhesion Strength.
The purpose of this test is to measure the adhesive strength of a material to determine whether the installation has been completed properly. Release or separation during the test will occur along the weakest part of the material, or bond between the material and the substrate.
Poor adhesion may be caused by poor substrate preparation, the surface being contaminated by water or dirt, not properly cured or improper primer application to name a few. For a traffic coating to function properly there must be proper adhesion.
To determine whether proper adhesion has been achieved, on-site testing needs to be conducted. The basic principle is very simple:
When attaching the adhesion tester (test dolly) to the coating material (coating) with the recommended adhesive1, ensure the specimen is not being pre-stressed by bumping or bending. You may slightly abrade the surface of the material to remove any surface film that could interfere with the recommended adhesive material. Make sure you clean the abraded area with Pecora recommended cleaning agent2 as to not affect the material or leave residue. Before conducting the pull test, make sure the deck coating application is fully cured (min 48 hours). It is very important the test area be flat as to achieve proper adhesion to the disc.
After the material has fully cured, perform the following test set up procedures:
Once the test is complete, you will need to analyze the material for maximum force achieve, the type of release, the surface in which the release occurred, and the percentage of release on each surface. This information should be noted in a test report using lbs. from the gauge.
In order to determine the pull-off value calculation:
Note: A minimum of 200 PSI is required for warranty purposes.
Any errors in the test should be examined to find its cause. If you discover that this error was caused from improper test procedures, do not include it on your report and perform another test. Any material that was damaged in the pull test needs to be replaced in accordance to Pecora’s instructions.
1The recommended adhesive is Gorilla brand Super Glue (clear)
2Depending on the project location, generally Xylene is recommended as the cleaning agent. Otherwise, an alternative VOC compliant solvent with quick evaporation is recommended.
For more information, testing questions, or deck coating application recommendations, we urge you to contact our Pecora Corporation Technical Services Group. Our expert team is highly qualified to answer any question, recommend the proper solution, or provide testing training. Our Technical Services staff offers training in product technology and use and provides the technical assistance you require in the planning and implementation of your project. They can be reached by email techservices@pecora.com or by phone (800)-523-6688.
Click or call (800) 523-6688.
Launch Calculator
Leave a Reply