> https://www.bigrentz.com/blog/how-forklifts-work
## The hydraulic system
![[01-hydraulics-2x.gif]]
1. **Fluid enters the hydraulic cylinder** through a special valve that allows it to enter without it escaping. Pressure increases as fluids increases in the cylinder.
**2. Upward force is created** when pressure is applied across the area of the piston head.
**3. The piston moves up** as a result of the force below it. This increases fluid and decreases pressure.
**4. Physical equilibrium** is achieved at this point when, at a given lift height, the fluids’ force is equal to the forklift load’s downward force.
## The roller chain pulley system
![[02-chain-pulley-2x-2.gif]]
1. Hydraulic pistons push the masts up.
2. Gears located on the mast are pressed against the roller chains.
3. The masts move up and pull the fork up.
## Controls
![[03-steering-lifting_zoom.gif]]
### Steering
- A forklift has an acceleration pedal, break, steering wheel, forward gear and reverse gear.
- Forklifts use ==rear-wheel steering==, meaning that the steering wheel controls the wheels in the rear.
### Lifting
- Pushing the lifting lever ==forward== moves the load ==up== while moving it ==backwards== moves it ==down==
### Tilting
The tilt function involves two more hydraulic cylinders found at the base of the masts
- ==Lever forward==: Air is pumped into the chamber. The ==rise in pressure== level pushes the piston head and results in the mast tilting ==away== from the frame.
- ==Lever back==: Air is gently released from the chamber and air is pumped into a secondary pair of hydraulic cylinders. The masts lean ==towards== the vehicle when those pistons push that pair of cylinders forward.