The successful manufacturing of an I.G. unit (insulated glass) is made possible, when the component suppliers and the I.G. fabricating operations work together to produce a quality I.G. unit. Quality control is the key for both suppliers and fabricators.

The purpose of this document is to bring you to an awareness of three important areas when using aluminum Air Spacer to manufacture I.G. units: (1) Technical details of aluminum Air Spacer and corner keys, (2) Why use aluminum Air Spacer, and (3) Actual details to look at when using aluminum spacer.

Technical details of Air Spacer & Corner Keys

Dual Seal Air Spacer

Single Seal Air Spacer

	Depth	-	The amount of penetration into the air cavity  parallel to the glass.
	Primary Seal	-	Seal closest to the sealed air cavity.
	Secondary Seal	-	Seal furthest away from sealed air cavity.
	Spacer	-	Hollow shape used to provide a fixed air Space between the 2 pieces of glass and a place where the desiccant is stored.
	Width	-	Dimension of air cavity between the 2 pieces of glass.
	Single Seal	-	Used when only one seal is required.
	Dual Seal	-	Used when two seals are required.

Types of Air Spacer joints and construction:

	-	Butt seam	-	Induction welded seam
	-	J-Lock	-	Micro Stitch
	-	Laser welded seam

Single and Dual Seal Air Spacers are produced to work with the different types of sealants:

	-	Hot melt butyl
	-	Two part polysulfides, urethanes and silicone
	-	Polyisobutylene (PIB) for a primary seal

Types of Air Spacer profiles available:

	Low profile (1/4 height)	-	Conventional cut and lay-up or 90 degree corner bending that will allow a lower sight line or an increase in sealant coverage.
	Standard (5/16 height)	-	Conventional cut and lay-up or 90 degree corner bending.
	Rectangular (5/16 height)	-	used in the linear extruder process.
	Decorative lite (5/16 height)	-	used for decorative lites that allows brass or zinc camen to be placed in center U-groove.

Standard Profile	Low Profile	Rectangular	Decorative Lite Profile

Surface finishes available:

	-	Mill finish, Aludized aluminum.
	-	Anodized clear, dark bronze, and light bronze.
	-	Painted top surface, available in a variety of colours.

Production Methods:

	-	Straight saw cut utilizing corners keys.
	-	Bent with two, three, or four bends utilizing 90-degree.
	-	corner keys and or an inline connectors.

Corner Keys and inline connectors:

	-	Made from; nylon, aluminum steel, or material for die-casting.
	-	Produced by injection molding, metal stamped, or die-casting.
	-	Nylon can be etched for better adhesion to sealants.
	-	90-degree corners, folding, flexible (for shapes), inline (straight connectors).
	-	Butyl inject or regular.
	-	Inline connectors can be nylon, aluminum, or steel.

	Fixed Corner	Butyl Inject Corner	Flex Corner
	Folding Corner	Metal Corner	Inline Connector

Why use Aluminum Spacer?

	·	Most widely used material to manufacture I.G. units.
	·	Adhesion
	·	Low capital cost
	·	Wide variety of manufacturing technologies.
	·	Cost effectiveness: strength & thermal performance.
	·	Strength when used for large units (commercial)
	·	Production versatility: sizes of air space – small/large fabricating facilities.
	·	IG units can be stacked for sealant application.
	·	Colour options: anodizing, top coat paint finishes.
	·	Easily transported.
	·	Excellent gas retention.
	·	Excellent moisture vapor barrier.
	·	Long shelf life.
	·	Easy to recycle: monetary value when disposed of

Details to Look at When Using Aluminum Spacer:

	·	The width and depth of the spacer are within acceptable tolerance (+/- .008 of an inch)
	·	Corner keys fit snuggly into spacer. The corner should not alter the width of the spacer.
	·	Spacer to be clean and free of any oil, waxes, or surface burrs.
	·	Test Method: Take a clean white rag or paper towel and wipe the aluminum spacer with as much hand compression as possible.  Examine the rag. Should not see oil, wax, or burrs appearing on the rag. Should see: a gray deposit, as aluminum depends on an oxide coating for corrosion resistance.  This coating will rub off on the rag and appear as a gray deposit that is expected and acceptable.
	·	Aluminum spacer thickness .012 to .016 thin for lower conductivity thicker for bend ability and strength.
	·	Packaging is adequate to protect against shipping and handling paper layering of the spacer will reduce chafing that occurs when two pieces of aluminum are rubbed together.  The chafing may cause black or gray marks on the spacer.
	·	It is recommended that spacer is stored in the shipping cartons until required.
	·	This will reduce the oxidizing of the spacer and reduce possible dust collection on the spacer to ensure a better seal to the sealants.

Summary

To ensure that a quality I.G. unit is made, the manufacturer must be aware of the technical details of aluminum Air Spacer, the reasons it is so widely used, and important factors an I.G. fabricator should consider when using aluminum Air Spacer.

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