Knowing When to Replace the Glass on Your Equipment

Do you have glass that is cracked or showing signs of wear? Replacing the glass on your equipment is crucial for maintaining job-site and operator safety. Understanding the type of glass on your equipment is key for knowing when it’s time to replace it.

Tempered Glass

Tempered glass is heat-treated to be much stronger than standard glass making it ideal for small earth moving equipment. Unlike regular glass, when tempered glass breaks, it shatters into small, blunt cubes rather than jagged shards. With a high scratch resistance and easy maintenance, tempered glass is best suited for mini excavators, compact wheel loaders, and backhoe loaders where the risk of high-velocity impacts are lower.

Knowing When to Replace Tempered Glass:

Deep scratches: If scratches are deep enough, it might have compromised the tempered tension layer of the glasses making the glass weaker and more prone to breaking.

Poor visibility: Large glares can lead to job-site accidents if the operator cannot see their surroundings clearly.

Edge chipping: Most tempered glass failures start at the edge, and the structural integrity of the pane is likely to fail if not replaced.

Laminated Glass

Laminated glass consists of 2 layers of glass with a plastic interlayer (PVB). With this technology, if this glass breaks, the glass fragments will stick to the plastic and hold together when shattered. This makes it much safer for the operator when broken and ideal for environments where there is a high-risk for impact. Laminated glass also provides excellent UV protection and noise reduction for loud environments. Equipment you will most likely see laminated glass is on skid steers and compact track loaders.

Knowing When to Replace Laminated Glass:

Delamination: A foggy or cloudy appearance creeping in from the seals which indicates that the interlayer has begun to peel away from the glass panes, usually starting at the edges.

Spider-webbing or large cracks: Laminated glass will stay together when cracked, but a crack in one layer puts double stress on the remaining layer. Rule of thumb: if the crack is longer than 6 inches or is located directly in the operator’s primary line of sight, it’s time to replace it.

Discoloration or yellowing: This can occur over years of exposure to UV rays on the job site and the interlayer can chemically break down. Look for a yellow or brownish tint that doesn’t wash off.

Bubbling in the center: Sometimes the bond between the glass and the plastic fails in the middle of the pane resulting in optical distortion making it harder for the operator to see clearly.

Polycarbonate Glass (Plexiglass)

Polycarbonate, also known as plexiglass, is the industry standard for extreme impact resistance. This material is best for high-hazard environments where heavy debris is flying towards the cab. This is much lighter than glass and it virtually unbreakable however, it scratches very easy and can yellow over time due to UV exposure. 

Knowing When to Replace Plexiglass:

Crazing (internal web): Crazing looks like thousands of tiny, microscopic cracks shimmering in the material due to exposure to UV rays or harsh chemicals. This is a sign that the molecular bonds of the plastic are breaking down and the material becomes more brittle than before.

Severe yellowing: Polycarbonate is sensitive to the sun, so overtime the UV rays can turn the clear plastic into a yellow color that distorts operator visibility. 

Deep scratches: Polycarbonate is much softer compared to glass which makes it a lot easier for the material to collect scratches. Replace when the scratches create a glare out and operator visibility becomes impaired.

Chemical fogging: If the window or windshield is cleaned with ammonia, gasoline, or certain degreasers, the surface will “fog” almost instantly. If the fogged spot is in the operator’s field of vision it cannot be fixed and should be replaced.