OVERVIEW

This Application Bulletin reviews the bond adhesive removal performance of ADM’s EnviroStri® wheat starch media and EnviroStrip® XL media. Both EnviroStrip® products offer a highly efficient adhesive removal technology with substantial cost savings and major quality improvements on metal-to-metal bonded parts. This technology is currently being used by several major aerospace organizations worldwide.

APPLICATION BACKGROUND

The most common application for bond adhesive removal with EnviroStrip® is metal-to-metal bonded aluminum aircraft sections and parts. During the bonding process, adhesive is pushed from the bond area, forming an unwanted bead line or smear of adhesive. This excess adhesive must be removed if it interferes with final assembly. Historically, aircraft manufacturers have removed unwanted adhesive material from bonded parts using a variety of methods, including hand-sanding, chemical application, and manual scraping techniques with tools such as chisels. These methods are very time consuming and often compromise the quality of the finished parts. The corrosion protection system - usually consisting of a chemical conversion coating and/or a bond primer - is often removed. Removal of any bond primer generally necessitates the additional task of re-priming affected areas. Needless to say, with these traditional methods, adhesive bond removal can be a potential problem area for aircraft manufacturers.

Bond adhesive removal is no longer a problem for several aircraft manufacturing plants. Many of these aircraft manufacturers now rely on ADM’s EnviroStrip® wheat starch media and EnviroStrip® XL products. This improved method for bond adhesive removal has a solid track record supported by six years of production use.

The EnviroStrip® products have proven to be faster and more economical to use, and greatly enhance the quality of finished parts by leaving the bond primer and/or chemical conversion coatings intact. This improved “adhesive deflash” process is now an integral part of the sub-assembly operations at leading airframe manufacturers. The gentle effect of the EnviroStrip® products on both aluminum and composite substrates allows it to remove the excess adhesive quickly, without removing the protective primer or damaging the underlying surface. It is also important to recognize that, when using EnviroStrip® products, post cleaning does not require solvents or chemical agents. A simple warm water wash will remove any dust or residues that remain on the part after treatment.

PROCESS PARAMETERS

1. A lower angle (20 ° – 40 °) is preferred for removing adhesive and helps to keep underlying primer or surface treatment completely intact.
2. Adhesive removal rates are dependent on the type of adhesive, thickness of material, and operator skill.

PROCESS EQUIPMENT

EnviroStrip® XL can be used in any light abrasive blasting machine and is particularly well suited for use in plastic media blast equipment. EnviroStrip® wheat starch media should be used in specially designed equipment, or any light abrasive blasting system fitted with appropriate modifications. ADM/Ogilvie can assist you in specifying equipment.

OPERATIONAL BENEFITS

• Reduced manpower requirements. Substantial cost saving is possible: as much as 4- to-1 over traditional methods.
• Major quality improvements. Compared to existing methods of adhesive removal EnviroStrip® and EnviroStrip® XL:
• Deliver a consistent surface finish without removal of bond primer/chemical coatings
• Eliminate reworking of treated areas
• Minimal risk of occupational hazards (e.g. Carpal Tunnel Syndrome associated with hand
  scraping).
• Environmentally safe. Waste is non-hazardous and can be disposed of as general refuse.
• Payback. Typically less than 1 year for capital investment in process equipment.

The information contained herein is correct to the best of our knowledge. The recommendations or suggestions contained in this bulletin are made without guarantee or representation as to results. We suggest that you evaluate these recommendations and suggestions in your own laboratory prior to use. Our responsibility for claims arising from breach of warranty, negligence, or otherwise is limited to the purchase price of the material. Freedom to use any patent owned by ADM or others is not to be inferred for any statement contained herein.

AB-SHE/07/01

Select ADM Biobased Media Series

EnviroStrip®
 (wheat starch)

EnviroStrip® XL
 (corn hybrid polymer)

eStrip ® GPX
 (starch-g-acrylic)