Rack and pinion rack and pinion china steering uses a gear-set to convert the circular motion of the tyre into the linear motion necessary to turn the tires. It also offers a gear reduction, therefore turning the tires is easier.
It works by enclosing the rack and pinion gear-arranged in a metallic tube, with each end of the rack protruding from the tube and linked to an axial rod. The pinion gear is mounted on the steering shaft so that when the tyre is turned, the gear spins, shifting 
the rack. The axial rod at each end of the rack links to the tie rod end, which is attached to the spindle.
Most cars need three to four complete turns of the steering wheel to move from lock to lock (from far to far remaining). The steering ratio demonstrates how far to carefully turn the steering wheel for the wheels to turn a certain quantity. A higher ratio means you need to turn the tyre more to carefully turn the wheels a particular amount and lower ratios supply the steering a quicker response.
Some cars use adjustable ratio steering. This rack and pinion steering system runs on the different number of the teeth per cm (tooth pitch) in the centre than at the ends. The effect is the steering can be more sensitive when it’s switched towards lock than when it’s near to its central placement, making the car more maneuverable.
There are two main types of rack and pinion steering systems:
End take off – the tie rods are mounted on the end of the steering rack via the inner axial rods.
Centre take off – bolts attach the tie rods to the center of the steering rack.
As steering is essential for controlling your vehicle, it’s important to diagnose and repair any steering problems as fast as possible.
The chances are your vehicle has rack and pinion steering.
Thankfully, the fundamentals aren’t hard to understand at all: it’s about turning rotational motion into linear. When you turn the tyre, this turns a steering column, which rotates the attached steering shaft and a worm gear known as the pinion. This gear sits on the ‘rack’, a length of metal with a series of teeth cut involved with it. So as the pinion rotates, the rack moves either left or right, based on your steering input.
Power steering adds a device to one side of the rack with a hydraulically actuated piston inside. A rotary valve directs hydraulic liquid to either the right or left part of the piston – depending on the steering direction – which applies strain on the piston and reducing your time and effort had a need to move the rack.
The rack-and-pinion gearset does a couple of things:
It converts the rotational motion of the steering wheel in to the linear motion needed to turn the wheels.
It provides a gear reduction, making it easier to turn the wheels.
On most cars, it takes three to four complete revolutions of the tyre to help make the wheels turn from lock to lock (from far left to far right).