Tag: Class

New TT-C-490 Revision F released for Chemical Conversion Coatings and Pretreatments for Metallic Substrates (Base for Organic Coatings)

TT-C-490 Revision F, “Chemical Conversion Coatings and Pretreatments for Metallic Substrates (Base for Organic Coatings),” has just been released and is available now from Document Center Inc. in either pdf or paper format.  This federal specification replaced MIL-C-490 and MIL-P-14504 and is one of the most commonly used plating specifications we sell.

TT-C-490F covers processes, pre-treatments, and pre-primer surface preparations of metallic substrates for coating applicators.  It covers metal surface preparation for delaying corrosion initiation and promoting primer adhesion. In addition, this specification covers the testing requirements for qualification of conversion coatings, the pre-treatments and pre-primer coatings.

The new 24-page revision has extensive changes from the now-obsolete 17-page TT-C-490E from 2002, so there are no lines in the margins showing you the updated material.   Changes appear to have been made throughout the document.

Document Center Inc. has been providing mil-specs and standards to industry for over 30 years, and since 1993 on our website, www.document-center.com. You can count on us to provide you with the latest information and updating services that are not available from many other sources.  Feel free to get in touch with us by phone (650-591-7600), fax (650-591-7617) or email (info@document-center.com).  We have the expertise to assist you with not only your standards purchases but other management services you need to keep your collection in good working order.

New Commercial Item Description A-A-59588 Revision B on Silicone Rubber

A-A-59588, the commercial item description titled “Rubber, Silicone,” has just been released as a new Revision B edition.  Available from Document Center Inc., the new document covers six classes of silicone rubber, in various grades.  GSA (the General Services Administration) has authorized it’s use by all federal agencies.

A CID (commercial item description) is an indexed, simplified product description that describes by function or performance characteristics of available, acceptable commercial products (often referred to as “off-the-shelf”) that will satisfy the Government’s needs.

The six grades covered by A-A-59588B are:

Class 1A – Low temperature resistant.
Grades – 40, 50, 60, 70, 80
Class 1B – Low temperature resistant and low compression set at high temperature.
Grades – 40, 50, 60, 70, 80
Class 2A – High temperature resistant.
Grades – 25, 40, 50, 60, 70, 80
Class 2B – High temperature resistant and low compression set.
Grades – 25, 40, 50, 60, 70, 80
Class 3A – Low temperature, tear and flex resistant.
Grades – 30, 50, 60
Class 3B – Tear and flex resistant.
Grades – 30, 50, 60, 70, 80

The silicone rubber is usually provided in the form of sheets, strips or tape; extruded shapes or tubing; or molded shapes, as specified in the government contract or purchase order.  Normally, dimensions and tolerances are indicated in the contract or purchase order as well.  If not, there’s 2 tables in the specification which cover commercial tolerances that can be used.

In this new edition, where changes from the previous issue were made, the margins are marked with vertical lines.  FYI: This was done as a convenience only and the Government assumes no liability whatsoever for any inaccuracies in these notations.

A-A-59588 is the document that replaced ZZ-E-765 (Rubber Fabricated Materials) when it was withdrawn in 2001.  For more information on other government documents on Rubber Fabricated Materials, see our page for the Federal Supply Classification number FSC 9320.

All publicly available federal level government documents are available from Document Center via our website, www.document-center.com.  You may prefer to contact us via phone (650-591-7600), fax (650-591-7617) or email (info@document-center.com).  We’re happy to assist you with all your standards requirements, including obsolete revisions, supersession information, monitoring, and auditing.  Just ask!