WINDSHIELD CRACK REPAIR IMPACT PENETRATION TESTING

Sample Description

United States Testing Company, Inc.

SAMPLE DESCRIPTION

193128-1R 12/27/93



The following glass was submitted and identified by the Client as:

A) 33 pieces of 12 inch by 12 inch by 1/4 inch thick repaired laminated glass. Each specimen consisted of two 1/8 inch thick pieces of glass, and contained a repaired crack located on one side of the glass. Some cracks extended from the center to one edge, and some extended from edge to edge.

B) 40 pieces of 10 inch long by 1 2/3 inch wide by 1/4 inch thick laminated glass. Each specimen consisted of two 1/8 inch thick pieces of glass.

1. a) Twenty each, with a repaired crack which ran across the width of each specimen. Ten of those were marked '6' and ten were marked '8'.
2. b) Ten each, identified as "original condition" and contained no cracks.
3. c) Ten each, identified as "cracked and unrepaired".
   

Requirements:

The dart may crack the glass and may puncture the test specimen. However, the hole so produced in the specimen shall not be sufficiently large to permit passage of the body of the dart completely through the test specimen. Small particles may disengage themselves from both sides of the specimen at and immediately around the point of impact, but no loose or detached pieces shall leave any area of the specimen exclusive of the area puncture by the dart. Furthermore, the glass on adjacent sides of each crack extending from the area punctured by the dart shall be held in place by the reinforcing of strengthening material, and no glass shall be freed from reinforcing or strengthening material for a distance greater than 1-1/2-in (38mm) from a crack. Spalling of the outer glass surface opposite the point of impact and adjacent to the area of impact is not to be considered a failure. No more than one specimen shall break into separate large pieces.

Results:

1. IMPACT, TEST 9 (DART DROP, 30 FT.) PER ANSI/SAE Z26.1-1990

(continued)

For each of the five specimens tested, the dart did not puncture the glass. The glass on adjacent sides of each crack extending from the area impacted by the dart was held in place by the reinforcing material. No specimens broke into separate large pieces. No separation or spalling of glass occurred at or near the repaired crack for each of the five specimens tested.

Conclusion:

The submitted repaired laminated glass met the requirements of Section 9 of ANSI/SAE Z26.1-1990, Impact, Dart Drop, 30 feet.

Procedure:

Twelve, 12 inch by 12 inch specimens were placed individually in the test frame with the repaired side face-up in the frame. The glass was then impacted once from a height of 30 feet using a 0.5 pound ste~l ball. Tests were performed on December 20, 1993.

Requirements:

The impact may product a large number of cracks in the glass; not more than two of the specimens shall break into separate large pieces. Furthermore, with no more than two of the remaining specimens shall the ball produce a hole or fracture at any location in the specimen through which the ball will pass.

At the point immediately opposite the point of impact, small fragments of glass may leave the specimen, but the small area thus affected shall expose less than 1 in2 (645mm2) of reinforcing or strengthening material, the surface of which shall always be well covered with tiny particles of tightly adhering glass. Total separation of glass from the reinforcing or strengthening material shall not exceed 3-in2 (1935mm2) on either side.

Spalling of the outer glass surface opposite the point of impact and adjacent to the area of impact is not to be considered a failure.

Results:

For each of the twelve specimens tested, none of the specimens broke into separate large pieces. The ball did not produce a hole or fracture at any location in the specimen through which the ball would pass. At the point immediately opposite the point of impact, the glass remained adhered to the reinforcing material. No separation or spalling of glass occurred at or near the repaired crack for each of the twelve specimens tested. 

Requirements:

The impact may product a large number of cracks in the glass and may cause tears in reinforcing interlayer material. The impact furthermore may produce a substantial permanent deformation in the shape of originally substantially flat specimen. However, with no more than two of the specimens shall the ball pass completely through the specimen within a 5-second interval after impact, either by what would be described as a puncture of the specimen or by means of the specimen fracturing into relatively large pieces that subsequently fold aside to permit passage of the ball.

When the specimen is clamped, the specimens during the test exhibiting more than 0.079-in (2mm) of movement at any point along the inside periphery of the frame shall be discarded and a new specimen substituted in its place.

Results:

For each of the ten specimens tested, the ball did not pass through the specimens. The specimens did not move more than 0.079 inches at any point along the inside periphery of the frame. No separation or spalling of glass occurred at or near the repaired crack. The repaired crack remained intact in each of the ten specimens tested.