Relying on cross balance supports to move up and down, scissor lifts are commonly used in settings where it’s necessary to work at height. As the name implies, as the lift goes up and down, the assembly begins to take on the appearance of a large set of connected scissor blades.
While you may understand the basics—including when to use a scissor lift and what it looks like when doing so—there’s more to learn. Let’s dive into how a scissor lift works.
To understand how a scissor lift works, you must first learn about the main parts of the machine. These include the following:
These scissor lift mechanisms and parts work together to ensure efficient and effective function.
Although the manner in which a scissor lift works depends on its power source, the movement is the same from one type of machine to the next. For example, a hydraulic scissor lift and a diesel lift don’t work in the same manner, but the way it functions is identical.
Here are the basics of how a scissor lift works:
When it’s time to return to the ground, the operator releases the pressure or fluid to reverse the process detailed above.
There are four primary ways to power a scissor lift. The type that you choose will impact the scissor lift mechanisms that you rely on.
Answer these questions to help choose the right power source:
As you address these questions, you can narrow your options to ensure yourself of making the right choice. For example, if you’re working outdoors and require a lot of power, a diesel-powered lift is best. Conversely, an indoor task is best left to an electric or pneumatic lift.
The use of any type of scissor lift comes with risks. For that reason, it’s critical to know how to use the machine, when to use the machine, and the steps you can take to minimize the chance of an accident.
Here are some of the many steps you can take to safely operate a scissor lift:
Even the most advanced and experienced operators are at risk when using a scissor lift, but these steps can enhance your safety. Get into the habit of regularly moving through these steps.
Understanding how scissor lifts work can help you choose the ideal power source when picking the right machine for your operations. Additionally, it’s essential to understand how a scissor lift works so you can recognize when issues arise and know the maintenance requirements.
When you’re selecting a scissor lift, turn to trusted selection at Aerial Titans. We’re the experienced equipment supplier for every project.
There are seven primary components of a scissor lift. These are the platform, base, scissor legs, cylinders, power source, down valve, and flow control valve.
The platform is what a worker and their equipment stand on, and the base is the foundation of the scissor lift. The scissor legs are what constrict or expand to raise or lower the platform, while the cylinders are also integral to this motion, and the power source powers the operation of the lift.
What about the valves? The valves serve as essential safety mechanisms, ensuring smooth and steady descents that keep workers safe.
The hydraulic fluid in the hydraulic system flows into the cylinders. As the fluid fills up those cylinders or drains out, this essentially tells the scissor legs to expand or constrict, which moves the lift up or down. Expanding raises the scissor lift’s platform while restricting lowers the platform.
When hydraulic fluid levels are incorrect, such as overfilled or underfilled, it can cause issues with the scissor lift’s operation. This is why it is vital to do routine fluid checks on your equipment2.
It is important to consider the safety of your workers when choosing the right scissor lift for your operation. While all scissor lifts should include a harness clipping point, a guardrail, and an emergency stop function, there are additional safety features to integrate.
These include mid-rails and toeboards to provide fall and drop protection, toe guards or beveled skirts to protect feet, sensors to prevent overloading and tilting, and manual lowering controls. It’s also vital to have alarms that are both audio and visual, as solely audio may not reach the ears of a worker who is deaf or using ear protection.
The power source of your scissor lift is an important aspect when choosing the right equipment for your operations. Those that use pneumatic power can raise and lower platforms without releasing fumes; they use air pressure for their power. This makes pneumatic scissor lifts a suitable choice for indoor work.
While diesel-powered lifts do release fumes, the power of diesel makes them outperform other power types when it comes to handling larger loads of workers and equipment. Choose diesel for outdoor work that requires a higher load-bearing capacity.
Electric lifts also do not emit fumes. Their power source makes them quieter and easier to maneuver. The ease of navigation often makes them the preferred choice for indoor work in tight or other constrained spaces.
Scissor lifts are expensive. They can also be dangerous when operators fail to follow proper safety protocols. A vital aspect of safe operation is ensuring that you follow the best maintenance practices for scissor lifts.
Your maintenance plan should include daily visual inspections, such as tire and power checks and identifying any possible leaks. Ensure that emergency functions are all operating correctly. Make sure all personal protection components are fully functioning and in the correct position. Additionally, do weekly fluid level and tire pressure checks. Look for structural issues during any type of inspections.
Always perform any regular or required maintenance in a timely manner.
A scissor lift operates around a central scissoring design, a crisscrossing mechanism that is inherently stable due to the equally distributed weight across the system. It’s important to note that a scissor is more stable the wider its center of gravity. Its center of gravity comes from the platform, so that a larger platform will equal more stability.
To create vertical movement, the scissor mechanism either constricts or expands. When the mechanism constricts, the platform lowers. When it expands, the platform rises. The speed and smoothness of this movement depend on the upkeep of the mechanism, as well as the type of power source.
