Standard: 1. ISO 4624 Paints and varnishes-Pull-off test for adhesion 2. ASTM D 4541 Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers 3. ASTM D7234 Standard Test Method for Pull-Off Adhesion Strength of Coatings on Concrete Using Portable Pull-Off Adhesion Testers
Application: In order to perform satisfactorily, coatings must adhere to the substrates on which they are applied. In practice, three different test procedures are used to assess the resistance of paints and coatings to separation from substrates:
Pull-off Test Adhesion of a single coating or a multi-coat system of paint, varnish or related products is assessed by measuring the minimum tensile stress necessary to detach or rupture the coating in a direction perpendicular to the substrate. This method maximizes tensile stress as compared to the shear stress applied by other methods such as scratch adhesion and results may not be comparable. The test is performed by securing a loading fixture (dolly) perpendicular to the surface of the coating with an adhesive. After the adhesive is cured, a testing apparatus is attached to the loading fixture and aligned to apply tension perpendicular to the test surface. The force applied is gradually increased and monitored until either a plug of coating material is detached, or a specified value is reached. The digital pull-off adhesion tester is a portable, hand-operated instrument which is used to measure the force required to pull a specified test diameter of coating away from its substrate using hydraulic pressure. The pressure is displayed on a digital LCD and represents the coating's strength of adhesion to the substrate. It evaluates the adhesion (pull-off strength) of a coating by determining the greatest tensile pull-off force that it can bear before detaching. Breaking points, demonstrated by fractured surfaces, occur along the weakest plane within the system consisting of dolly, adhesive, coating layers and substrate. Test Principle Coating or a multi-coat system of paint is applied/distributed to substrate uniformly with a certain thickness. After coating has been dried or cured, adhere dolly to surface of coating directly with special adhesive. After the adhesive is cured, use the digital pull-off adhesion tester to attach the loading fixture and aligned to apply tension perpendicular to the test surface. Tester pull off the dolly at a speed of 1MPa/s by hydraulic pump, and measures the force required to pull a specified test diameter of coating away from its substrate using hydraulic pressure, this force is shown through the LCD of tester. Characters Portable design, can be used anywhere. Built-in rechargeable lithium battery, no need any external power source. Selectable directly four different sizes dolly for different resolution and testing range Get the testing results from LCD directly. Includes all tools needed for testing High-precise professional sensor ensures 0.001MPa resolution Self-aligning dollies ensure to get a reliable testing results for smooth or uneven surfaces. Two units (MPa and psi)for selection and can be converted automatically. Showing pull-off rate allows users monitor and adjust pull speed according to different test requirements. Main Technical Parameters Test range: 0-10KN Dolly Size: 20mm(Standard);10mm,14mm,50mm(Optional) Resolution: 0.001KN/0.001MPa Accuracy: =<±1% Full scale Max. Pull-off Pressure:Φ10mm dolly →0-127.38 MPa;Φ14mm dolly→0 - 64.99MPa; Φ20mm dolly→0-31.84 MPa;Φ50mm dolly→0-5.09 MPa; Power:Built-in rechargeable lithium battery, and standard configuration charging adapter.
Adhesion Tester Weight:2.8KG