7 Jun ASTM A states zinc-rich paint with zinc dust in the ranges of % or above 92% in the dried film are equally effective. Why is there a gap. ASTM A Practice for Repair of Damaged and Uncoated Areas of Hot-Dip Galvanized Coatings details how to repair a damaged hot-dip galvanized coating . ASTM Designation: A (American Standard Testing Method). Standard Practice for Repair of Damaged and Uncoated Areas of Hot-Dip Galvanized Coatings.
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The thickness of the applied coating shall be as agreed upon between the contracting parties. Home Tags Login Register Search. Finally, a visual inspection to confirm the level of cleanliness must be carried out to ensure the standard is met.
ASTM A780-Zinc Dust in Paint
Each system shall be used independently of the other without combining values in any way. For less critical field exposure conditions, blast clean the surface to near-white metal, in accordance with SSPC-SP10 1 to astn mil 25 to 50 m anchor patternas a minimum. Do not average the readings, as this requirement was removed from the specifications in It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application.
It is the responsibility of the user of this standard to establish appropriate safety and health practices ashm determine the applicability of regulatory limitations prior to use.
Hand tool cleaning with a stiff-bristle or nylon brush does not meet asfm.
This standard is subject to a70 at any time by the responsible technical committee and must be reviewed every five years and if not revised. This practice can also be used to repair hot-dip galvanized coatings damaged by excessively rough handling during shipping or erection.
ASTM AZinc Dust in Paint | American Galvanizer’s Association
Zinc-based solder products closely match the surrounding zinc and blend in well with the existing coating appearance. Apply the paint as recommended by the paint manufacturer in a single application employing multiple spray passes to achieve a asgm film thickness to be agreed upon between the contracting parties. To ensure that a smooth reconditioned coating can be asfm, surface preparation shall extend into the undamaged galvanized coating.
Correct for the additional tape thickness i. Requirements concerning the renovation of uncoated areas remaining after initial hot-dip galvanizing are contained within the applicable material specification. ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard.
Anyone making use of this information assumes all liability arising from such use. A number in parentheses indicates the year of last reapproval. The practice is the same, but there are more restrictions to the allowable repairs on a new product than one that has been in service.
Touch-up materials are required to meet a coating thickness of at least 2. This standard has been approved for use by agencies of the Department of Defense. The six-part video series will provide highly beneficial asgm aids to those needing assistance with satm the requirements of ASTM A Similarly, contracting parties shall agree to the repair method to be used.
ASTM A contains three acceptable methods of touch-up and repair of hot-dip galvanized steel: S780 practice can also be used to repair hot-dip galvanized coatings damaged by excessively rough handling during shipping or erection. For all surface preparation methods, cleaning must extend into the surrounding, undamaged galvanized coating.
Surface Preparation Always check for visible contaminants on the surface of the repair area just prior to mechanical cleaning. However, do not clean excessively beyond the area of repair.
Repairing HDG Steel | American Galvanizer’s Association
The specification explains how to use the various repair methods as well as the required coating thickness for the repaired area. Zinc-rich paint is applied to a clean, dry steel surface by either a brush or spray. Experience shows that in general. A listing of various manufacturers and products for the maintenance and repair of hot-dip galvanized a80 is available for download.
Annex A3 describes the use of sprayed zinc.
August 1, Authored by Alana Hochstein. Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard. Each system shall be used independently of the other without combining values in any way. The material provided herein has been developed to provide accurate and authoritative information awtm after-fabrication hot-dip galvanized steel.
Current edition approved May 1, Zinc spray, or metallizing, is done by melting zinc powder or zinc wire in a flame or electric arc and projecting the molten zinc zstm by air or gas onto the surface to be coated.
Apply the sprayed coating as soon as possible after surface preparation and before visible deterioration of the surface has occurred.
Annex A1 describes the use of zinc-based solders. Experience shows that in general organic zinc-rich systems are more tolerant of surface preparation. Last previous edition approved in as A — 01 No further reproductions authorized.