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.
The 7 Main Parts of a Scissor Lift
To understand how a scissor lift works, you must first learn about the main parts of the machine. These include the following:
- Platform: Scissor lift platforms come in many sizes and shapes. Regardless of the setup, the platform is used to raise and lower workers and their equipment.
- Base: The base is the foundation of the lift. Made of metal, it has tracks to guide rollers located at the bottom of the legs. This allows for a steady raising and lowering motion.
- Scissor legs: Scissor legs are attached to the base. As they constrict, the platform raises. And as they expand, the platform lowers.
- Cylinders: Scissor lifts are designed with anywhere from one to four cylinders. The contents of the cylinder(s) depend on the type of lift. For example, a pneumatic and hydraulic lift won’t use the same system.
- Power source: Scissor lifts are powered in many ways, including hydraulics, pneumatic, electric, and diesel fuel.
- Down valve: Used to ensure that the lift doesn’t descend too quickly, the down valve controls the flow of hydraulic fluid or compressed air.
- Flow control valve: This valve manages the speed of the descent.
These scissor lift mechanisms and parts work together to ensure efficient and effective function.
What Happens When Using a Scissor Lift?
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:
- The scissor lift power source is turned on, which fills the cylinder(s) with compressed air or hydraulic fluid.
- The compressed air or hydraulic fluid is moved from one part of the scissor lift to another.
- As the cylinder pushes outwards, the legs begin to push apart.
- As the legs push apart, the platform slowly raises.
When it’s time to return to the ground, the operator releases the pressure or fluid to reverse the process detailed above.
Power Source Options
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.
- Hydraulics: These scissor lifts use hydraulic liquid for power. These are among the easiest-to-use machines, with minimal training required. However, they’re not the best choice if you need serious power and/or speed.
- Pneumatic: With the help of air pressure, these scissor lifts can efficiently move up and down without fumes. This makes pneumatic scissor lifts a top choice for indoor operation.
- Electric: Electric scissor lifts are silent, easy to maneuver, and don’t emit fumes. They’re often preferred in tight indoor spaces, such as warehouses and distribution centers.
- Diesel: Powered by diesel fuel, these are the most powerful scissor lifts. They can carry more people and equipment, making them a good choice for larger outdoor projects.
Answer these questions to help choose the right power source:
- Are you using the lift indoors or outdoors?
- Do you need a lot of power?
- Are you working in a tight space?
- Is noise a concern?
- Are emissions a concern?
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.
Safety Tips for Operation
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:
- Get the proper training: Only people with proper training should use a scissor lift. If you’re not comfortable using a lift, ask for assistance.
- Conduct a pre-operation inspection: This allows you to pinpoint any damage or defects that could put you at risk. Pay close attention to parts such as the emergency stop button and brakes.
- Review the surrounding area: Doing so allows you to clear it of any safety hazards, while also informing co-workers of your intentions. This is an important step no matter if you’re using a lift indoors or outdoors.
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.
The more you learn about how scissor lifts work, the more confident you’ll be in your ability to use the machine appropriately and safely.
The most important thing to remember is that no two types of scissor lifts are identical, even if that appears to be the case. Choose the one that is best for the specifics of the project you’re taking on.