Measure adhesion of coatings to metal, wood concrete and other rigid substrates
Conforms to international standards including ASTM D4541/D7234, ISO 4624/16276-1, AS/NZS 1580.408.5 and others. Available in Automatic or Manual
models.
All Models Feature
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Environmentally sealed enclosure â weatherproof, dustproof and shockproof - meets or exceeds IP65
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Inexpensive, single-use dollies eliminate cleaning for re-use and can be kept as a permanent record
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Self-aligning aluminum dolly enables accurate measurements on smooth or uneven surfaces
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10, 14, 20 or 50 mm dollies maximize capability and measurement resolution across a wide range of bond strengths
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Calibrated and certified to + / - 1 percent accuracy using a NIST traceable load cell
Measures the force required to pull a specified test diameter of coating away from its substrate using hydraulic pressure.
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Overview
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Electronically controlled hydraulic pump automatically applies smooth and continuous pull-off pressure. Greatly reduces user effort
and the risk of influencing the pulling process
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Impact and scratch resistant color touch screen with keypad for operation with or without gloves
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Built-in rechargeable battery performs over 200 tests per charge. Continue testing with AC power while the battery recharges.
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Environmentally sealed enclosure â weatherproof, dustproof and shockproof - meets or exceeds IP65
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Rubberized, shock absorbing grips provide a stable, skid-resistant footing
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Self-aligning aluminum dolly enables accurate measurements on smooth or uneven surfaces
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10, 14, 20 or 50 mm dollies maximize capability and measurement resolution across a wide range of bond strengths. Maximum pull-off pressure by dolly size...
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10 mm: 14000 psi (96 MPa)
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14 mm: 7000 psi (50 MPa)
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20 mm: 3500 psi (24 MPa)
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50 mm: 560 psi (3.8 MPa)
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User selectable measurement units: psi (pounds per square inch), MPa (Megapascal), Nmm2 (Newtons per millimeter square) or Newton (force)
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User adjustable pull rate, pull limit and hold time
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Rotating display for horizontal and vertical use
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Pressure system is calibrated and certified to ± 1 percent accuracy using a NIST traceable load cell
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Conforms to international standards including ASTM D4541/D7234, ISO 4624/16276-1, AS/NZS 1580.408.5 and others
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Memory and Reporting Features
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Internal memory stores maximum pull-off pressure, rate of pull, test duration and dolly size for 100,000 pulls in up to 1,000 batches
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Record the results as pass/fail and the nature of fracture - cohesive, adhesive and glue failures
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Wirelessly connect to your smart device using our free PosiTector App (Apple iOS and Android)
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Add images and notes using the camera or keyboard
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Create customized, professional PDF reports
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Share, backup, synchronize and report measurement data
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Auto-pairing Bluetooth (BLE) connection
Positector App Features
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Add images and notes using the camera or keyboard
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Create customized, professional PDF reports
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Share, backup, synchronize and report measurement data
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Auto-pairing Bluetooth (BLE) connection
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Use the touch screen to interact with menu options. Swipe horizontally to navigate between views or vertically to move between batch
readings. Alternatively, the keypad can be used for navigation and selection.
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User adjustable dolly size, pull rate,
pull limit and hold time.
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Batch summary provides an at-a-glance review of test results.
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View test parameters and reading results. Reading is recorded as pass or fail based on set test parameters. The pass/fail results can be revised.
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Notes can be added for each reading.
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Include a note for a batch (group) of readings.
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Record the nature of failure - cohesive, adhesive and glue failures.
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Recording the Nature of the Fracture
Upon completion of a pull-off test, the dolly and coated surface should be examined. In addition to pull-off force, many National and International standards
such as ASTM D4541 and ISO 4624 require the nature of the fracture to be recorded.
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Cohesive fracture: fracture occurs within a coating layer (same coating on dolly face and coated surface).
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Adhesive fracture: fracture occurs at the interface between layers (coating on dolly face differs from surface).
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Glue failure: visible separation of the glue from itself, the coating or dolly (no coating visible on the dolly face).
The cohesive and adhesive fracture visual analysis can be recorded using the PosiTest AT-A's keypad or touch screen display.
Alternatively, the information can be reported using the PosiTector App.
Fractures are visually estimated and recorded as a percent of each. The two layer example below illustrates a cohesive fracture within coating layer 1 and
layer 2 (visually estimated at 50% each). Recorded results are included in reports.
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The PosiTest AT-A can record fracture information for up to five layers. For full details and examples see Visual Analysis and Recording
of Test Results.
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Model Selection
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two Models Avaliable with either 20mm or 50mm dollies
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Order Code
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ATA20
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ATA50
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Dolly size and stand off*
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20 mm
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50 mm
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Typical Applications
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Coatings on metal
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Coatings on concrete,
wood and plastic
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Range
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0.7 - 24 MPa
100 - 3500 psi
100 - 7550 N
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0.4 - 3.8 MPa
50 - 560 psi
100 - 7550 N
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Resolution
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0.01 MPa (1 psi)
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Accuracy
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+ / - 1 percent Full Scale
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Kits Include
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ATA20: 20 mm dollies (20), 20 mm cutting tool and 20 mm stand off
ATA50: 50 mm dollies (8), 50 mm cutting tool and 50 mm stand off
Automatic Adhesion Tester, built-in rechargeable NiMH battery with charger, abrasive pad, glue with mixing sticks and palettes, cotton swabs, USB cable,
PosiSoft Software, instruction booklet and video, Certificate of Calibration traceable to NIST, two-year warranty, and a sturdy, lightweight carrying case
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*Optional 20 and 50 mm Accessory Kits allow each model to be used with alternative dolly sizes. Custom 10 and 14 mm dollies are available for special
applications (compatible with 20 mm stand off).
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Are the PosiTest AT instruments rugged?
Absolutely. With an environmentally sealed, metal enclosure, heavy-duty hydraulic pump and a high grade industrial pressure sensor, both the Manual and Automatic PosiTest AT are built to last. They
can be used indoors, outdoors and in all types of weather.
How are the Manual and Automatic PosiTest Adhesion Testers calibrated at DeFelsko?
The Manual and Automatic PosiTest Adhesion Testers are calibrated against known conditions using NIST traceable equipment. A Certificate of Calibration containing actual measurements is included
with every tester.
How much time should be allowed for the included Resinlab EP11HT Gray to cure?
Full cure can be obtained after 24-48 hours at room temperature. Cure time can be accelerated by the application of heat. See Technical Data Sheet for full details.
Are curved dollies available for convex surfaces?
We do not provide or support the use of curved dollies for adhesion testing.
In addition to affecting the surface area used in calculating pull-off strengths and the direction of the force lines (creating unwanted shear forces), most adhesion testing standards specifically
call for the use of flat dollies.
Feedback from our customers is that most internal or external pipe
applications greater than 200 mm in diameter do not require curved dollies for satisfactory results. In such cases the maximum glue gap between the surface of the dolly and the coating is 0.5 mm.
For smaller pipe diameters, depending on the expected pull-off strength of the coating, it may be possible to use a 10 mm or 14 mm dolly. The smaller surface areas of the dollies will allow them to
sit flatter on the curved surface. The height of the actuator pulling the dolly becomes the limiting factor within internal diameters. External diameters can be decreased to as low as 50 mm and 100
mm respectively.
If you have more specific information on the application it may be possible to provide a more definitive response.
Can pull-off adhesion tests be conducted underwater?
The PosiTest can be used for underwater measurement provided only the cable and actuator are placed under the surface. In such cases, the following precautions should be
taken:
- The standoff and actuator should be thoroughly dried immediately upon completion of testing.
- Once dried, a generous amount of lubricant should be applied to discourage corrosion (rust).
Note: During measurement, the manual PosiTest AT may require more than one continuous stroke to complete the test. This differs from our recommendation in the instruction manual and operational
video.
PosiTest adhesion testers can be specifically manufactured with longer pressure hoses to facilitate underwater measurement.
Where does failure occur?
Tensile adhesion pulls are evaluated in pounds per square inch (psi) or megapascals (MPa), and visually, as follows:
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Cohesive fracture: fracture occurs within a coating layer (same coating on dolly face and coated surface).
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Adhesive fracture: fracture occurs at the interface between layers (coating on dolly face differs from surface).
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Glue failure: visible separation of the glue from iteself, the coating or dolly (no coating visible on the dolly face).
PosiTest AT-A models can record fracture information for up to five layers.
