 |
| Purchase Information |
| Use this form to request purchase information on GMW online subscriptions. |
|
|
Document GMW GMW14100 is offered by IHS as part of an online subscription. This subscription contains many documents on the same topic.
You may also purchase this document alone from the IHS Standards Store.
GMW GMW14100 Document Information:
Title
Corrosion Protective Coatings Phosphate/Zinc Organic Type
GM Worldwide
Publication Date:
Dec 1, 2006
Scope:
This standard covers the basic requirements for a corrosion protective coating process consisting of zinc phosphate pretreatment, a non-electrolytically applied zinc rich coating, and an organic top coating. Shot blasting as pretreatment in place zinc phosphate is permissible for externally threaded parts or parts with no thread. Shot blasting is not a preferred method for internally threaded parts and shall not be used for nut- washer assemblies. The coating may be applied by dipping or spraying. Part configuration dictates the application process. Internally threaded parts (nut) shall be coated in a canting centrifuge or equivalent equipment.
Note: Any additional approved source of this finish shall have canting centrifuge application or equivalent equipment.
Material Description.
The coating system is free of hexavalent chromate, with no hexavalent chromate in final product per GMW3059 requirements. GMW3034 will be used as a referee test. This coating process does not generate hydrogen; however, pretreatment processes i.e. acid pickling could cause hydrogen absorption. Non-electrolytically applied zinc rich coating has high permeability, which allows effusion of hydrogen during curing that might have been absorbed during acid pickling.
Symbols. Not applicable.
Typical Applications.
The coating is suitable for bolts, clips, and other ferrous parts where above normal levels of corrosion protection and freedom from hydrogen embrittlement are required.
This finish is not recommended for 360 degree Nylon Patch Nuts.
Internal threaded parts e.g., Nuts < M6 may need different treatment.
Remarks.
Use of this finish on threaded surface and/or bearing surface of joints could affect the torque-tension relationship. It is recommended that a torque-tension study of the fastener joint should be preformed before releasing this finish on a new application.
Coefficient of friction/torque tension values in this specification are also determined at ambient temperatures. New applications for this finish should be tested to confirm performance under application specific, operating conditions.
Finishes conforming to the requirements of this specification can be used in the application range of -50 to 120°C. For applications outside of this temperature range consult your local Material Engineering (Paint & Corrosion engineering for GME) support.
About IHS
IHS (NYSE: IHS) is a leading global provider of critical technical information, decision-support tools and related services in a number of industries including aerospace and defense, automotive, construction, electronics, and energy. IHS serves customers ranging from large governments and multinational corporations to smaller companies and technical professionals in more than 100 countries. IHS been in business for more than 45 years and employ more than 2,300 people around the world.
