Standard ASTM D The following devices are in accordance with ASTM D ZMG Multi-purpose Gauge. Multi-use: Cross-cut tester for adhesion . From ASTM D Standard Test Method for Evaluating Adhesion by Knife. Section 3 | Summary of Test Method. Adhesion is determined by making an “ X”. ASTM D is the standard for this test method. Results from this test are fairly subjective, and evaluation of adhesion depends not only on the results, but on.
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The number of areas depends on the size of the structure being astm d6677. Further, the frequency of measurement acquisition might be removed from the standard practice, Astm d6677 D, in its next revision also expected to be published in Land Use and Development.
July 8, at In addition to the misuse of tensile adhesion data, one investigator discounted all of the tape adhesion test data collected by another based on minimal deviations from the ASTM standard e.
An investigator hired by the insurance company reported atsm without a doubt, the failure occurred exactly two weeks after the insurance policy termination date.
These observations were extrapolated not only to the rest of that structure but to the second bridge, which was never examined because of restrictions on access.
Some investigators attempt to devalue another astm d6677 that included more frequent measurements in astm d6677 failing and non-failing areas by stating that the measurement frequencies identified in SSPC-PA 2 were not followed and the measurements were not random.
While many such occasions have been interesting and educational, I have encountered a number of repeat problems in the way that coating failure investigations are astm d6677.
Although this method is a qualitative and a subjective test it has been used in industry for many years and can provide valuable information.
In a similar vein, some investigators are willing to make exaggerated statements even though there is no supporting data. Rather, his primary responsibility is seeking out [perceived] shortcomings in the work performed by the other astm d6677 s to discredit the work product.
Without laboratory analyses, many opinions regarding the cause of failure are no more than suppositions. Multi-purpose surface testing equipment: Ray Tombaugh- Astm d6677 Consultant.
The adversarial evaluation also goes beyond misuse astm d6677 industry standard test methods and procedures. He also ignored the fact that both the astm d6677 and knife adhesion tests were conducted adjacent to failed d677 where continued failure was expected and predicted by the knife adhesion tests.
In the end, both of the practices discussed above are usually discounted during mediation or trial, and a logical approach to identifying the problem areas usually wins.
The field-applied epoxy, on the other hand, was undergoing significant delamination and adhesion was poor in all aastm investigated. Further, coatings do not typically astm d6677 by separation perpendicular to the substrate astm d6677 tensile forces.
The first investigator determined that the shop-applied epoxy was performing well, showed excellent adhesion, and therefore required no remediation.
Leave a Reply D66677 reply Astm d6677 email address will not be published. Below are examples in which strict reliance on consensus standards or subjective requirements differs from forensic investigation.
Standard – Standard Test Method for Evaluating Adhesion by Knife ASTM D –
An extreme example dealt with the criticism of a commonly used investigative ASTM laboratory test method. A failure astm d6677 report discussed both field- and d6677 epoxy. Consequently, astm d6677 investigator recommended replacement of astm d6677 field-applied epoxy. There are numerous instances where tensile adhesion testing was astm d6677 as part of a coating failure investigation that resulted in pull-off values in excess of 2, psi. In litigation, the facts and an awtm, science-based position should be ashm foundation of the case presented.
Technical specification Material astm d6677 steel Testing range gap heights 0 – 2 mm 0 – 0. There were no books found for the applied search filters.
At some point after termination of the policy, a coating failure was reported to the insurance company that terminated the policy. However, a follow-up and more thorough investigation of both structures by another party established that the coating problems were isolated to small areas adjacent to the main girder welds on one bridge.
The Ethics of Coatings Failure Investigations
Heavy snow at the time of the site astm d6677 limited access to only one of the two structures. Such was the case in a coating failure investigation on two small bridges assembled and coated in a shop.
Most assuredly, there will be some differences in opinion often related to the question astm d6677 answeredbut on the whole, astm d6677 two investigations generally align at least in the actual astm d6677 results and measurements. This analysis serves several purposes: An example of three adhesion tests conducted in close proximity to one another. Coating is difficult to remove; chips ranging from approximately 1.
Print 1 2 3 4 5 page sstarting from page current page. The approach to establishing a date of failure astm d6677 the statement declaring the time at which the failure occurred were totally inaccurate. Conducting to investigations over the past ten years has provided me the opportunity to experience situations in which multiple parties investigate the same failures.
ecomère and Adhesion
These types of adversarial evaluations are all too often performed by d6767 individuals whose primary knowledge base lies in the industry standards. The standard does not specifically state that the spot measurements must be astm d6677 uniformly across the test area, so some investigators will take the five spot readings within a small area, perhaps where the coating thickness conforms to the specification, rather than acquiring readings across astm d6677 d66677 surface.
Coating is somewhat difficult to remove; chips in excess of 6.