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):||13 September 2004|
|PDF File Size:||9.66 Mb|
|ePub File Size:||6.12 Mb|
|Price:||Free* [*Free Regsitration Required]|
Courtesy of SSPC The number of areas that must be measured for coating thickness varies, depending on the asrm of the coated area. Are there any industry standards that address peak count versus simple profile that may only indicate a few peaks at that height. The scale is not linear. Obtaining coating thickness measurements according to the frequency described in SSPC-PA 2 across the entire structure may be of little value during a coating failure investigation and can be cost prohibitive.
Click Here to Asrm the Updated Article. A minimum and a maximum thickness are normally specified for each layer of coating. Pipe sections that are loaded onto a cart or rack can astk considered a complete unit Figure It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Level 1 is the most restrictive and does not allow for any deviation of spot or area measurements from the specified minimum and maximum thickness, while Level 5 is the least restrictive.
Acquisition of more than three gage readings within a spot is permitted. It includes definitions of key terms, reference documents, the significance and use of the practice, the advantages and limitations of coating thickness gages, and a description of test specimens.
The revisions took five years to complete.
December 7, at 6: Even if a project speci? Arguably the most critical section in the document, Section 8, describes how many areas to check, the size of the areas, the number of measurements to obtain in each area, and the steps to take if spot or area measurements do not conform to the specification.
He holds an A. If no Restriction Level is specified, default is based on conformance requirement. This average BMR is then deducted from subsequent coating thickness measurements to remove any effect of the base metal surface and its conditions.
Obtaining base metal readings with Type 1 gage.
Measuring Dry Film Coating Thickness According to SSPC-PA 2KTA University
Provisions for measuring on soft or tacky coatings are described in. Change is never easy… communicating the new requirements of this standard to the industry is astmm, but essential. For example, a thin coating applied to a ferrous substrate will require greater spring tension to pull the magnet off than will a thicker coating, since the magnet is closer to the ferrous substrate with the thinner coating.
The average of the acceptable gage readings is the spot measurement.
Measuring Dry Film Coating Thickness According to SSPC-PA 2
Requirements for frequency and location of instrument readings and evaluation criteria to ensure that the profile over the entire prepared surface complies with project requirements are included in the Standard. January 29, at This process is described later in this article. A one-year calibration interval is a typical starting point suggested by gage manufacturers.
This article was a very helpful reference for me when I was updating my company coating spec. The number of spot measurements along the edge will vary depending on the total length of the coated edge.
Depending on the coating type and the prevailing service environment, the specifier can select the dry film thickness restriction level for a astk project. Provisions for measuring on soft or tacky coatings are described in 5.
February 5, at 2: On a larger structure with multiple applicators, the measurement e7091 documentation process could be extensive, so the approach was changed in the revision.
One conduit is through training and education. This standard was published in and will require updating to reflect current technology. Two of the eight appendices were added in the remaining were in the edition and are highlighted below. Leave this field empty. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory asstm prior to use.
Updates to SSPC and other industry-provided inspector training and certification courses and the associated instructor education will be critical to fully understanding and effectively communicating the requirements of this highly regarded industry standard.
Link to Active This link will always route to the current Active version of the standard. However, several Type 2 electronic gage manufacturers offer a variety of probe configurations, some of which are less affected by proximity to edges and are designed to better measure the thickness of coatings on edges Fig. Leave this field empty. For the purpose of final acceptance of the total dry film thickness, the cumulative thickness of all coating layers in each area must be no less than the cumulative minimum specified thickness and no greater than the cumulative maximum specified thickness.
NOTE 1—This practice addresses only metal substrates. Accuracy statements frequently include a? Active view current version of standard. Adjustments to the gage may or may not be required. Verifying accuracy of Type 2 gage using a certified shim Adjusting Type 2 Gages The final step in the process is to adjust the gage on the surface to which the coating will be applied. More recently within the past year or soTestex developed a new replica tape, which when inserted into the DeFelsko PosiTector Replica Tape Reader RTR-P produces 3-D color image of peak density and displays peak height as well as peak density Pd, peaks per inch2.
Also, uncoated shims of flat plastic sheet with assigned values traceable to a national metrology institution. These steps include 1 gage calibration, 2 verification of gage accuracy and 3 gage adjustment. Correction for Base Metal Reading if acquired. A one-point or two-point accuracy verification procedure can be performed as described earlier for Type 1 gages. The number of areas that must be measured for coating thickness varies, depending on the size of the coated area.
The total number of spot satm area measurements is based on the total square footage of pipe on the cart or rack. Addressed measurement of asttm on steel only.
One of a variety of Type 2 gage probe configurations designed to better measure DFT of coatings on edges.