Simple
- • Inexpensive, single-use dollies eliminate cleaning for re-use and can be kept as a permanent record
- • 10, 14, 20 or 50 mm dollies maximize capability and measurement resolution across a wide range of bond strengths
Durable
- • Environmentally sealed enclosure – weatherproof, dustproof and shockproof – meets or exceeds IP65
Accurate
- • Self-aligning aluminum dolly enables accurate measurements on smooth or uneven surfaces
- • Calibrated and certified to ± 1% accuracy using a NIST traceable load cell
Key Features…
- • Manual hydraulic pump designed to apply smooth and continuous pressure with a single stroke
- • Pull Rate Indicator to manually monitor and adjust the rate of pull
- • Environmentally sealed enclosure – weatherproof, dustproof and shockproof – meets or exceeds IP65
- • Self-aligning aluminum dolly enables accurate measurements on smooth or uneven surfaces
- • 10, 14, 20 or 50 mm dollies maximize capability and measurement resolution across a wide range of bond strengths
– 10 mm: 10000 psi (70 MPa)
– 14 mm: 6000 psi (40 MPa)
– 20 mm: 3000 psi (20 MPa)
– 50 mm: 480 psi (3.3 MPa)
– 50×50 mm: 375 psi (2.585 MPa) - • Every PosiTest Adhesion Tester pressure system is calibrated and certified to ± 1% accuracy using a NIST traceable load cell
- • Internal memory stores maximum pull-off pressure, pull rate, test duration and dolly size for up to 200 pulls
- • Compatible with PosiSoft Desktop software for viewing, printing and storing measurement data
- • Software Updates via web keep your instrument current
Key Features…
- Electronically controlled hydraulic pump automatically applies smooth and continuous pull-off pressure. Greatly reduces user effort and the risk of influencing the pulling process
- Impact and scratch resistant color touch screen with keypad for operation with or without gloves
- Built-in rechargeable battery performs over 200 tests per charge. Continue testing with AC power while the battery recharges.
- Environmentally sealed enclosure – weatherproof, dustproof and shockproof – meets or exceeds IP65
- Rubberized, shock absorbing grips provide a stable, skid-resistant footing
- Self-aligning aluminum dolly enables accurate measurements on smooth or uneven surfaces
- 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…
– 10 mm: 14000 psi (96Â MPa)
– 14 mm: 7000 psi (50 MPa)
– 20 mm: 3500 psi (24 MPa)
– 50 mm: 560 psi (3.8 MPa) - User selectable measurement units: psi (pounds per square inch), MPa (Megapascal), Nmm2Â (Newtons per millimeter square) or Newton (force)
- User adjustable pull rate, pull limit and hold time
- Rotating display for horizontal and vertical use
- Pressure system is calibrated and certified to ± 1% accuracy using a NIST traceable load cell
- Software Updates via web keep your instrument current
Memory and Reporting Features
- •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
- •Record the results as pass/fail and the nature of fracture – cohesive, adhesive and glue failures
- •Wirelessly connect to your smart device using our free PosiTector App (Apple iOS and Android)
- •WiFi technology wirelessly communicates with PosiSoft.net, downloads software updates and allows access to stored measurement data using standard web browsers (see WiFi Features for full details)
- •PosiSoft USB Drive – stored readings and graphs can be accessed via USB using universal PC/Mac web browsers or file explorers. No software required
- •Compatible with PosiSoft Desktop, PosiSoft.net and PosiTector App (Apple iOS and Android) software solutions
Is the PosiTest AT calibrated at the factory?
The PosiTest AT arrives fully calibrated and ready to measure. A Long-Form Certificate of Calibration traceable to NIST or PTB is included, which documents actual readings taken by your instrument at our calibration laboratory on standards traceable to a national metrology institute. Beware of ‘Certificates’ or ‘Certificates of Conformance’ offered by competitors. These typically do not include actual instrument readings, and are often insufficient to meet common quality requirements.
Is the PosiTest AT portable, and suitable for use in the field?
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. Weatherproof, dustproof and shockproof, they can be used indoors, outdoors and in all types of weather (meets or exceeds IP 65).
For added utility and convenience, PosiTest AT-A Automatic models also include a handy shoulder strap and rubberized grips.
Does the PosiTest AT include steel loading fixtures (dollies)?
The PosiTest AT is supplied with self-aligning dollies that are precision-manufactured from strong and lightweight aluminum alloy (6061-T6). As a lower-cost alternative to steel loading fixtures, DeFelsko aluminum dollies are a single-use/consumable item and ideal for keeping as a permanent visual record of testing.
Do you have a recommended adhesive for my particular application?
The ResinLab EP11HT epoxy adhesive supplied with the PosiTest AT is simple to use and suitable for testing a wide range of coating types. Â In some instances, specialized coatings will require a more specialized adhesive.
Is the PosiTest AT-A more accurate than the PosiTest AT-M?
The certified accuracy of both PosiTest AT models is identical. However, the fully automatic design of the PosiTest AT-A provides improved measurement consistency by eliminating the potential for operator influence from the test process.
What is the difference between the 20mm and the 50mm loading fixtures?
The 50 mm dolly is commonly recommended for use with concrete, wood and composite substrates, and measures coatings with expected adhesion values between 50 psi and 560 psi (50 – 500 psi for AT-M models). The 20 mm dolly is recommended for testing coatings applied to metals or with expected adhesion values greater than 500 psi.
Can I use the PosiTest AT-A on curved surfaces?
Yes. Feedback from our customers is that the PosiTest AT gages are suitable for testing most internal or external pipe applications greater than 200 mm in diameter. Â In such cases, the maximum glue gap between the surface of the 20 mm 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. External diameters can be decreased to as low as 50 mm and 100 mm, for the 10 mm and 14 mm dollies, respectively.
DeFelsko does 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.
How many measurements can I take with the PosiTest AT-A on a single battery charge?
The rechargeable battery pack (user replaceable) in the PosiTest AT-A can perform over 200 tests on a single charge. Use the included AC adaptor to continue testing as the battery recharges.
What is the lowest adhesion strength that the PosiTest AT-A can measure?
When utilized with a 50mm diameter dolly, the PosiTest AT is in a priming state until reaching a priming pressure of 16 psi. It is only after the priming pressure is reached that the instrument begins calculating and displaying the pull rate.
While it is possible to obtain readings below this priming pressure with the AT-M model, the AT-A automatic does not allow the operator to build priming pressure very slowly and is therefore not suitable for use below the priming pressure.
Note that all reported adhesion values (including those obtained below the priming pressure) are subject to the PosiTest AT gage’s full-scale accuracy of ± 1% (± 30 psi, AT-M; ± 35 psi, AT-A).
Is there a faster curing adhesive than the epoxy supplied with the PosiTest AT?
The versatile epoxy adhesive supplied with the PosiTest AT reaches full cure within 24 – 48 hours. Operators who require faster cure times should evaluate other adhesives for their compatibility with both the coating being tested and our aluminum test dolly. Cyanoacrylate (‘super glue’) type adhesives are often sufficient for lower pull-off strengths.
Can I use the PosiTest AT on flexible or brittle substrates?
The PosiTest AT is designed for use with rigid, structural substrates. A flexible substrate can adversely impact test accuracy and repeatability. Furthermore, use of the PosiTest AT for measuring the adhesion of coatings applied to a brittle substrate typically results in the destruction of the substrate material, making it challenging to quantify the coating-substrate bond strength.
