I know of several incidents of glass falling off trolleys, and in one case causing significant injury to a worker.
Glass is by its nature a heavy, fragile, and sharp product. Quality handling and transportation systems for glass are specific to the industry. The key suppliers of this equipment globally number around 10, with those companies typically making a range of storage, lifting, and handling products. Each manufacturer has their own systems and components which they have developed with their key clients over a long period of time. Most general fabricators avoid glass handling and transportation as they recognise that this is an industry suited to specialised rather than general equipment. The one anomaly seems to be trolleys.
I've always had a policy of advising customers when I think their trolleys are unsafe. Possibly some customers think this is part of my sales pitch, and maybe it is, but I also consider it my duty to the industry to speak up if I believe they are using unsafe equipment. The most common area of concern is castors. If a castor fails the glass will most likely tip and fall.
A typical 2 metre long A-frame trolley with 200mm ledges and 1700mm tall has the ability to carry around 2 tonnes of glass. I drive a Holden ute which weighs around 2 tonnes. Moving a loaded trolley around a factory is therefore equivalent to pushing my Holden ute around. Why is it then that so many trolleys use lightweight castors not rated for heavy duty applications?
I challenge you to check the castors on the trolleys in your factory.
1. Check the diameter of the castors. Glass trolley castors should have a diameter of at least 150mm
2. Check the castors load rating. If it is built for heavy duty application it will have a rating of at least 400kg per castor.
3. The forks that hold the castor wheel are a common point of failure. Well designed castors will have strong fabricated steel forks. Lighter duty castors will have pressed steel forks which are typically lighter and weaker, and prone to failing by folding over.
4. Check for wear in the swivelling mechanism (if it has one).
5. Check for general wear on the outer surface of the castor. A heavy weight castor will take many years to wear under normal load.
6. Check the shaft and bearing in the centre of the castor. This should be firm and show no signs of wear
7. Check where the castor is attached to the trolley
If in doubt, replace!
If you want help with your factory handling equipment you know where we are, and we are keen to help!