Canada is cold, and if you are in the heavy-lifting industry then this is something you need to be aware of when using your [lifting equipment][1]. In fact, using your lifting equipment properly in cold conditions is essential to the proper functioning and longevity of your equipment.
Even more crucially, thinking about crane and operator safety in cold conditions is important for the safety of your employees.
So, how exactly does cold weather impact your steel crane equipment and what should you consider when working in these kinds of temperatures? Sparta Engineering explores the answers to these questions here.
How does cold weather impact steel?
Low temperatures can adversely affect the tensile toughness of many commonly-used materials in the engineering world.
Tensile toughness is a measure of a material’s brittleness or ductility (the tendency to deform before fracturing); it is often estimated by calculating the area beneath the stress-strain curve.
Ductile materials – These materials absorb significant amounts of impact energy before fracturing, resulting in tell-tale deformations.
Brittle materials – Brittle materials, on the other hand, tend to shatter on impact.
In general, materials with high ductility and high strength have good tensile toughness. However, depending on the material, tensile toughness can be very sensitive to temperature changes.
Cold weather temperatures can negatively affect the safe working capacity of cranes and heavy-lifting equipment. The steel in these pieces of equipment can experience a shift from ductile to brittle if the temperature drops below a certain point.
This shift is known as the “ductile-to-brittle-transition” temperature (DBTT), the “nil-ductility transition” temperature, or the “15 ft*lb transition” temperature, and the temperature at which this shift occurs varies from material to material.
What steel can be used to reduce the impact of cold weather?
According to the ASTM A514 standard, QT-100, a type of high-tensile plate steel, has excellent low-temperature properties – although it is not recommended for structural use below -46ºC as it can become very brittle.
Due to its excellent low-temperature properties, some engineering companies are using this material to make equipment that is specifically designed for lower temperatures. The steel, which gains its characteristics from the process of quenching and tempering, possesses improved strength and flexibility when compared to other steel products.
What should be considered when working in freezing temperatures?
While engineers have found a way for steel to be safer in low temperatures, it’s still incredibly important that those operating cranes and heavy-lifting equipment in freezing conditions should take safety precautions.
It is common for most engineers to specify a minimum operating temperature of -20°C, as it is easy and cost-effective. However, it is more than likely that many pieces of equipment will be used at lower temperatures than that.
Switching to a quenched and tempered steel can give you a crane that is able to operate in – 40°C. However, many companies are using equipment that has a -20°C rating at -30°C or colder. This means they are completely liable for doing so and cannot predict the mode of failure.
It’s important that you are aware of what temperature you can operate your equipment at.
By being aware of the dangers of operating the equipment in cold temperatures, you can ensure that your employees are safe from potential accidents and that your business hits project deadlines.