What are Final Drive Parts and How They Work on an Excavator

Introduction

Excavator final drive, travel motor and gears parts are the main items of excavator operation. Excavator final drive is used to output power to track so that excavator can move. Travel motor drives final drive to rotate, and gear parts realize the transmission of power. Operators or repairmen of excavator, constructors who engage in construction, or earth-moving industry need to know these parts.

What are Excavator Final Drives?

Excavator final drive is the last part of the entire excavator power transmission chain. Usually, they are the last part of an excavator track-drive system; that is to say, the function of a final drive is to reduce the output shaft of the engine from high speed, low torque to low speed, high torque so as to drive the excavator itself as a heavy load.

Since the final drive is usually knocked and damaged by external forces on-site, they have to be covered in a sturdy case for their own safety.

As far as we know, excavators used on actual construction sites should work properly without failure when it comes time to move them; therefore, a working final drive will certainly help your excavator travel across all kinds of terrains perfectly fine.

According to the size and model of different excavators, the design of an excavator’s final drive can vary according to the situation. Of course, this refers to large excavators mostly. Small excavators would likely only come with very simple designs in their final drives.

In any case, regular inspections of an excavator’s final drive are extremely important. Checking the oil level and condition within the final drive housing is something you’ll want to do quite often too because otherwise, things like worn out, damaged parts might appear before your eyes.

How do Travel Motors Work?

Travel motors are used to transform the hydraulic energy into mechanical energy to drive the final gear. Travel motors work according to the law of fluid pressure: when they contain some liquid oil, these fluids push inside pistons or gears to rotate and then pass this turning action to the end engine that finally rotates the excavator tracks.

During traveling, you can adjust the flow quantity and pressure of the travel motor; accordingly, different speeds and torques will occur for your machine’s travel. Thus, it increases excavator productivity while working on light duty digging or heavy duty pushing and pulling in any construction site.

At times, certain malfunctions occur due to many problems related to track machines’ parts like pumps, controls, valves, etc. It is vital to ensure proper movement and operation of an excavator by using quality travel motors and maintaining them correctly, especially regarding its travel motor parts, so no faults hamper the excavator’s movements.

What are Gear Parts in Excavators?

Gear parts of excavators, such as spur gear parts, helical gear parts and planetary gear parts, play an important role in the whole process of power transmission.

Simple-spur-gear part is a kind of general parts with less load capacity; this kind of wheel only transmits driving force at two meshed gears. Compared with ordinary gears transmitting force by friction without sloping angle between two meshing teeth, the helical gear part has the characteristics of smoothness and silence. Besides, planet wheels are often used in the final drive and travel motor sets of excavator equipment, and planetary gear sets can achieve wide range speed change in small space.

In summary, generally speaking, these kinds of parts will be selected from some alloy steel products according to actual conditions, so that it not only meets the requirements for strength but also bears great stress under working environment with great torque.

Usually, in practical application, excavators need higher precision machining when processing different forms and sizes to ensure the module meshes properly, which means there is no impact or resistance among them. These kinds of gear components may face very serious situation if they are damaged in various ways, for example, chips, break segment, etc.

What are the Common Problems of Final Drives?

Among excavator common faults, oil leakage is quite common for final drive. After so many years’ usage, we cannot prevent from damaging the seals of final drive house. So you will find leaking from hydraulic cylinder on working fluid reservoir.

In the beginning it seems nothing. But if not dealt with properly, it would cause lots of disadvantages because oil leaks are no longer lubricating and cooling internal parts. What’s more, such problems also made us feel terrible in using equipment due to dirty environment caused by it. The leaked hydraulic liquid can damage other machines placed nearby when doing works.

Wearing noises sometimes happen because some key parts in final drives get less tightness after running them too long. The gear has worn out; the bearing becomes loose over time. When gears do not work well, they tend to make lots of sounds while moving. We can determine what is wrong based on its own characteristics: uneven speed, unsmooth movement, etc. That is something really dangerous happening, as our final drive could stop working soon without timely repairing.

And also, overheated condition. Just like car engine, final drive of excavator always runs in an extreme hot atmosphere even if we did not do anything in it. High operating temperature may come from two aspects: lacking working liquid or machine being loaded beyond capacity. Of course, this fact will bring additional burden to whole system – more energy needed here, faster burning up elsewhere. When things go this way, then broken-up component is waiting ahead!

How to Maintain Travel Motors and Gear Parts?

You also need to maintain the running motor and gears every day to extend their service life. Check how much hydraulic oil has been added to the running motor. Try to keep it in a certain scope, without any impurities. The filter should be replaced according to the time interval specified by the manufacturer to avoid pollution with dirt and sand.

And as for gear parts: if they are greased well (with good lubricants), and there is plenty of grease on them, then nothing will happen to them. Of course, visually you can notice some signs of wear, cracks in teeth, and pieces chipped off. Then you’ll have to replace damaged gear parts after installing them, while proper adjustment of their positions isn’t a bad idea either.

Have you ever worked in this field and come across excavator final drives, traveling motors, or other gears? I would like to hear your opinion in the comments! Share this text with your friends if you think it’s useful.

FAQ

What does a final drive do on an excavator?
A final drive takes power from the engine and turns it into force. This force helps the excavator move, turn, and climb over rough ground.

How to make sure if a final drive is failing?
People may hear strange noises or see oil leaks. The excavator might move slower or lose power. Metal bits on the drain plug also show wear inside the drive.

How often should someone check the final drive oil?
Operators should check the oil every 100 hours of use. Clean oil keeps the gears safe. Dirty or low oil can cause damage.

Can I replace a final drive at home?
Most people need special tools and skills to replace a final drive. Usually the trained technician can do the job safely and correctly.