This standard is issued under the fixed designation F ; the 1 This specification is under the jurisdiction of ASTM Committee F16 on. ASTM: F – Standard Specification for Chromium/Zinc Corrosion Protective Coatings for Fasteners. 1. Scope This specification covers the basic. ASTM F/FM Standard Specification for Zinc/Aluminum Corrosion Protective Coatings for Fasteners. standard by ASTM.
|Published (Last):||26 July 2013|
|PDF File Size:||4.52 Mb|
|ePub File Size:||8.80 Mb|
|Price:||Free* [*Free Regsitration Required]|
That said, I do not know much about fluorocarbon d1136 and how they are applied. But there are some doubts. The coatings are classified into six grades Grades atm to 6 according to the required minimum basecoat thickness, and when tested, shall conform accordingly to appearance, adhesion, corrosion resistance, blister, thread fit, and hydrogen embrittlement requirements.
Hi, Recently we were informed that Dacromet coating is being phased out. As for the thickness of both coatings, F grade 3 specified a coating thickness of 0.
We are not sure how fragile the coating is during installation. No other units of measurement are included in this standard. What corrosion-resistant coatings are available for high-strength over ksi bolts? Normally where I asstm F specified is in applications with higher strength fasteners that cannot be hot-dip galvanized, such as ASTM A heavy hex bolts. Leave this field empty. Depending on the amount of corrosive forces at work in the application, F may be sufficient, but it may not.
Since the bolts are pre-tensioned, will there be any issues with Magni with regard to pre-tensioning i. The corrosion protection offered by F in those cases would be superior to nothing at all.
High Strength Bolts Coatings
Work Item s – proposed revisions of this standard. Protective Coatings ASTM recommends aastm if a protective coating is required for A bolts, one of two approved coatings is recommended.
We also see no issues with pre-tensioning. We assumed that the properties on the bolts is not affected but the final tension might be change? One year after installation the bolts are rusting.
ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.
Jovito- We would be happy to quote your specific bolting needs if you want to send us a list of the bolts you are looking for. The coating process does not induce the possibility of internal hydrogen embrittlement provided that the fasteners have not been cleaned or pre-treated with an acid or phosphate.
F Grade 3, commonly known as Dacromet. Is fluorocarbon coating acceptable to A bolts for corrosion prevention?
Alkaline cleaning or vapor degreasing is required along with shot blasting to remove rust or scale. 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.
Is the coating that fragile? The basecoat can contain chrome C or be non-chrome NC. Since we are using A bolts in our structure, we have to propose a replacement. The tightening torque may vary from plain finish or other coatings, but the bolt should still function the same.
Serge- We have very little experience with Dacromet coating. Due to hydrogen embrittlement concerns ASTM recommends against hot-dip galvanizingmechanical deposition, or electroplating with zinc or other metallic coatings on high strength bolts ultimate tensile strengths that exceed ksi.
High Strength Bolts Coatings – Portland Bolt
I suppose they are similar to painting. They were used to in flange type splices of two tubular monopole sections. However, these fasteners wstm not as readily available in the marketplace as A Type 1. This abstract is a brief summary of the referenced standard. Since the Dacromet and Magni will be in contact with one another, Are they compatible with one another?
Leave a Reply Cancel reply Your email address will not be published. Link to Active This link will always route to the current Active version of the standard. Historical Version s – view previous versions of standard. If so, did the tension will be higher? The bolts and nuts are already coated with Dacromet and the proposal is to coat the DTI washers with Magni 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.
Your first question, is it appropriate to specify ASTM F Grade 3would be best answered by an engineer familiar with the coating and the application. It is required that the bolt and nut are coated by the same process, but the washer can be an alternate coating.