Engineering vehicles, known by the other terms: construction equipment, earth movers, heavy equipment or just plain equipment, are machines, specifically designed to execute civil engineering and construction engineering tasks. The scope of the specialized manufacturing industries covered by the previously mentioned engineering fields is broad, encompassing in no order: construction, logging, mining, waste management, military engineering and agriculture. These machines are most often associated with earthworks (engineering). These engineering vehicle machines, in the most basic form, are compound machines composed of simple machines. These components make up the five equipment systems: implement, traction, structure, power train, control and information . Through the mechanical advantage of a simple machine, the ratio between input force applied and force exerted is multiplied. Currently most equipment use hydraulics as a primary source of transferring power. The use of heavy equipment has a long history. Vitruvius a 1st century B.C. engineer gives detailed descriptions of Roman heavy equipment and Roman cranes in his treatise De Architectura.
Heavy equipment requires specialized tires for various construction applications. While many types of equipment have continuous tracks applicable to more severe service requirements, tires are used where greater speed or mobility is required. An understanding of what equipment will be used for during the life of the tires is required for proper selection. Tire selection can have a significant impact on production and unit cost. There are three types of off-the-road tires, transport for earthmoving machines, work for slow moving earth moving machines, and load and carry for transporting as well as digging. Off-highway tires have six categories of service C compactor, E earthmover, G grader, L loader, LS log-skidder and ML mining and logging. Within these service categories are various tread types designed for use on hard-packed surface, soft surface and rock. Tires are a large expense on any construction project, careful consideration should be given to prevent excessive wear or damage.
* see Heavy equipment operator
The National Association of Heavy Equipment Training Schools provides American national certification for heavy equipment operator
Currently there is not an international association of heavy equipment schools.
For an expense to be classified as an ownership cost it must be incurred regardless of if the equipment is used or not. These costs are as follows:
Depreciation can be calculated several ways, the simplest is the straight-line method. The annual depreciation is constant, reducing the equipment value annually. The following are simple equations paraphrased from the Peurifoy & Schexnayder text:
m = some year in the future|
N = equipment useful life (years)
and Dn = Annual depreciation amount
Book value (BV) in year m
N = 5
purchase price = $350,000
m = 3 years from now
For an expense to be classified as an operating cost it must be incurred through use of the equipment. These costs are as follows:
The biggest distinction from a cost standpoint is if a repair is classified as a major repair or a minor repair. A major repair can change the depreciable equipment value due to an extension in service life while a minor repair is normal maintenance. Major repairs are charged to the equipment and minor repairs are charged to the job. It is advantageous for projects to classify all repairs as major while the equipment department will desire to classify all repairs as "minor" and charge the work to a job.