This standard is issued under the fixed designation D ; the number 1 This practice is under the jurisdiction of ASTM Committee D01 on Paint and. Related. In nearly the same timeframe, the version of ASTM D, “Standard Practice for Nondestructive Measurement of Dry Film Thickness of. ASTM D describes three operational steps that must be performed prior to coating thickness measurement to help assure the reliability of.
|Published (Last):||23 September 2014|
|PDF File Size:||16.50 Mb|
|ePub File Size:||15.29 Mb|
|Price:||Free* [*Free Regsitration Required]|
However it will be important to place a measured shim onto asstm prepared, uncoated pipe and adjust the gage to match the shim thickness to remove any effect of the base metal. Your email address will not be published.
We have allowed it to become more technologically complex while making the data easier to analyze.
Don, The standard is independent of the substrate type, as long as the substrate is a ferrous or non-ferrous metal. Qstm type of magnetic gage referenced in original SSPC-PA 2 for measuring dft Figures courtesy of the author except where otherwise indicated.
Measuring Coating Thickness According To SSPC-PA 2 – Update 2015
Pipe sections loaded onto a cart or rack can be considered a complete unit Fig. Section 10, Reporting was added to the standard in The square footage is calculated as:.
Frequency for Measurement of Coating Thickness 8. Adjustment of Type 2 gages to compensate for substrate characteristics described later is typically performed using certified shims. For areas containing less than square feet atm coated surface, every square foot area must be measured for coating thickness.
For best accuracy when measuring with magnetic induction principle gages, consider the following: Six appendices from version included.
Measuring Dry Film Coating Thickness According to SSPC-PA 2KTA University
Most Type 1 magnetic pull-off gages do not require a power source for example, batteries. Accordingly, these gages cannot distinguish the thickness of individual layers after they have all been applied. Within each area, five randomly spaced spots are selected. Isolation of nonconforming areas required measurement of each square foot area painted during the work shift.
Acquisition of more than three gage readings within a spot is permitted. This standard was published in and will require updating to reflect current technology. NOTE 4—Test panels may be fabricated from thin gage materials and special consideration for calibration adjustment may be required.
One of the issues that needs to be explained and discussed is using Test-Tex paper for measuring profile. Appendix 7 was added to accommodate pipe coaters that need to determine coating thickness conformance on non-flat or non-plate areas, including smaller pipe sections on a cart or rack and longer pipe spools. Accuracy statements provide the performance capability across the full functional measurement range of the gage.
Acceptable spot measurements are defined by the minimum and maximum values in the contract documents. This will determine whether the gage is operating correctly 3.
Measuring Dry Film Coating Thickness According to SSPC-PA 2
The BMR is the effect of substrate roughness on a coating thickness gage. The most current version of the ASTM standard focuses on proper gage use, while SSPC-PA 2 focuses primarily on the frequency of measurements and the acceptability of the acquired measurements. Even if a project speci?
I am assuming you are using an electronic gage:. There are three categories of coated area: February 5, at 2: It is recommended that the gage be veri? Accuracy statements frequently include a? Three sets of astk circumferential spot measurements should be obtained on pipe spools less than 10 feet in length. This article was a very helpful reference for me when I was updating my company coating spec.
Measuring Coating Thickness According To SSPC-PA2 – Update KTA University
This procedure also verifies that the probe configuration will accommodate the edge configuration before acquiring coating thickness data. Provisions for measuring on soft or tacky coatings are described in.
Yet the requirements of SSPC-PA 2 regarding gage calibration, verification of gage accuracy and adjustment procedures, the number of measurements to obtain, and the tolerance of the measurements is complex and should be fully understood by the specification writer before invoking it in a contract. For areas of coating to 1, square feet, three random areas are selected and measured. For a given measurement direction or unit measurement, any compliant area or unit preceding a non-compliant area or unit is designated as suspect, and, as such, is subject to re-inspection after corrective measures are taken.
Equipment manufacturers produce non-destructive coating thickness testing gages that are used to measure the cumulative thickness of the coating layers, after they are dry. DFT of pipe spools not loaded on cart or rack are typically measured individually. Spot measurements are obtained in each direction up to the maximum surface area coated during the work shift until two consecutive conforming spot measurements are sstm in that direction, or until no additional measurements can be made.
Three sets of four circumferential spot measurements should be obtained on pipe spools less than 10 feet in length. Once astn of accuracy and adjustments are made, a minimum of three gage readings are taken within 1. Gage operation should be veri?
Shim stock typically has an inherent curve. The number of areas that must be measured for coating thickness varies, depending on the size of the coated area. For example, if the intended use is between 4 and 6 mils, then a 5-mil coated standard is appropriate.
Acceptable spot measurements are defined by the minimum and maximum values d77091 the contract documents. Spot measurements are obtained on repeating structural units or elements of structural units until two consecutive units in each direction are conforming or until there are no more units to test.
For example, if a gage reads 5.