PowerPoint Presentation: 5/1/2013 1 EARTH MOVING EQUIPMENTS CONSTRUCTION & WORKING OF POWER SHOVEL: 5/1/2013 2 CONSTRUCTION & WORKING OF POWER SHOVEL POWER SHOVELS: 5/1/2013 3 POWER SHOVELS Power Shovels are used primarily to excavate earth and load it into trucks or tractor pulled wagons or onto or onto conveyor belts. They are capable of excavating all classes of earth, except solid rock, without prior loosening, like in quarries, mines in any road projects etc. Power shovels are considered as basic tool for excavating the materials and loading. They may be mounted on crawler tracks, in which case they are referred to as crawler mounted shovels. Such shovels have very low travel speeds. However, they may be mounted an rubber-tired wheels. Single-engine self-propelled units are powered and operated from excavator cab. The non-self-propelled units mounted on the rear of tracks, which are referred to as truck-mounted, have separate engines for operating them. POWER SHOVELS: 5/1/2013 4 POWER SHOVELS The basic parts of a power shovel include the mounting, cab, boom, dipper stick and bucket or dipper and under carriage unit. Power unit Under carriage unit Hoist and loading assembly: It is used for hoisting the dipper and loading the material into predetermined place. It essentially consists of rigid boom and dipper stick which is strongly built to withstand impact loading while excavation. To operate shovel in favorable condition i.e. economically, it will be necessary to reduce the depth of penetration of dipper face. POWER SHOVELS: 5/1/2013 5 POWER SHOVELS The general operation of a hydraulically controlled shovel differ from those of a cable-controlled shovel primarily in that the operator forces are produced by pistons instead of by cables. Hence, it is clear that the applications of power shovel are 1) To excavate the soils of all types except rocks without prior loosening. 2) To collect and dump the material. 3) To load the excavated material into dump trucks, conveyer belts etc. SCRAPERS: 5/1/2013 6 SCRAPERS SCRAPERS: 5/1/2013 7 SCRAPERS Scrapers are the result of a compromise between the best loading and the best hauling machines. Scrapers are used to scrap the ground, load it simultaneously, then transport it over a distance, dump at the desired place and then spread or layered. The ability of these machines to deposit their loads in uniformly thick layer will facilitate the succeeding spreading operation On the return trips to borrow pits the cutting blades of scrapers may be lowered enough to remove high spots, thereby assisting in maintaining the haul roads. Thus, scrapers are designed to dig, load, haul, dump and spread. Therefore sometimes it is called “ Carryall. SCRAPERS: 5/1/2013 8 SCRAPERS It essentially consists of a large scoop provided with cutting edge. The scoop is in the form of bucket on hollow container, which is known as bowl or body. The scoop can excavate, transport and dump the material wherever required. The cutting edge of scoop does the excavate work and the excavated material goes on collecting in howl from the front gate. The material is transported to the site of dumping and is taken out from the tailgate of the bowl. Then facilitate the succeeding spreading operations to required and uniform thick layer. Types of Scrapers: 5/1/2013 9 Types of Scrapers Scrapers may be broadly classified into two main categories 1) Crawler — tractor scraper 2) Wheel — tractor scraper. a) Single — engine b) Twin — engine c) Two — bowl tandem d) Elevating Scrapers. DUMPERS: 5/1/2013 10 DUMPERS DUMPERS: 5/1/2013 11 DUMPERS Dumper is also known as Dump truck. The motor vehicle which is specially designed & constructed for carrying the heavy loads under various operations conditions can be called as Dumpers. These are meant for carrying rocks, coal, minerals, aggregate and other materials in construction works. Dumper may be ON road Vehicle or OFF road vehicle. ON road Dumpers generally used in normal roads such as in road construction, while OFF road means, vehicle is used apart from good words, i.e. in terrains like in dam construction mines etc. DUMPERS: 5/1/2013 12 DUMPERS The constructional features of Dumper is similar to that heady duty truck, except a high strength container or trolley is mounted at back side of the Cabin and Hydraulic assisted load raising and lowering facility is provided for dumping material in the trolley. Some dumpers may have 2 hydraulic cylinders and the size of rear wheel and number of rear axles may vary with load carrying capacity and mode of operations. DUMPERS: 5/1/2013 13 DUMPERS Suspension at front is of rigid elliptical type and at rear heavy duty leaf springs are provided to absorb high impact loading under severe operating conditions. Container for dumper is specially constructed to withstand ill handlings. Heavy duty air cleaner, filter, share proof mountings of all instruments, dust proof electrical systems and cushion mountings for radiator may present in some dump trucks. Dumpers play important vole in dam construction, road making, mining etc. for carrying materials and dumping at required place quickly and conveniently. PowerPoint Presentation: 5/1/2013 14 Any Questions?