I K GUJRAL PUNJAB TECHNICAL UNIVERSITY Construction Machinery & Works Managements Guided by:- Ar. Fuzail Jawaid
Bulldozer Prepared by:- Anand kumar 1633851
WHAT IS BULLDOZER Machines designed preliminary for cutting & pushing material relatively short distance . Consist of a tractor with a front mounted blade controlled by hydraulic cylinders use for different cut for different depth & leveling as per condition of land. A bulldozer is a crawler ( continuous tracked tractor) equipped with a substantial metal plate ( known as a blade ) used to push large quantities of soil, sand, rubble, or other such material during construction or conversion work and typically equipped at the rear with a claw-like device ( known as a ripper ) to loosen densely compacted materials. Anand 1633851-civil
The term “bulldozer” is often used to mean any heavy equipment (sometimes a loader and sometimes an excavator ), but precisely, the term refers only to a tractor fitted with a dozer blade . Primary Tools of a BULLDOZER are :- Blade Ripper Bulldozer Blade ripper Anand 1633851-civil
Parts of bulldozer Anand 1633851-civil
Line diagram ripper
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PURPOSE OF BULLDOZER Clear site of work Leveling of land Prepare roads on hilly areas as well as hard ground Excavate the material and haul in between 100 meters distance. Spreading earth Backfilling trenches Maintaining haul roads Anand 1633851-civil
Bulldozer Sketch
CLASSIFICATION OF BULLDOZERS: ** It may either cable controlled or hydraulic controlled. Depending upon mountings bulldozers classified as C rawler tractor mounted bulldozers Wheel tractor mounted bulldozers Depending on nature of blade: Front casting dozer Angle dozer * In case of front casting dozer blade is fixed perpendicular to the direction of travel. * In case if Angle dozer the blade is fixed at an angle with the direction of travel Anand 1633851-civil
CRAWLER MOUNTED BULLDOZERS
WHEEL TRACTOR MOUNTED BULLDOZERS
COMPARISON : In case of front casting dozer it moves earth in the forward direction . In case of Angle dozer it moves earth one side in the forward direction . Due to this different types of blades it can converted in two types. Anand 1633851-civil
FRONT CASTING DOZER
ANGLE DOZER
BLADES OF DOZER The bulldozer blade is a heavy metal plate on the front of the tractor , used to push objects, and shove sand, soil and debris. Made from mold boards which having concave profile . Blades are connected with dozer with the help of push arms and tilt cylinders or a C frame. Based on different type of work application the size of blade is varies . Ripper The ripper is the long claw-like device on the back of the bulldozer . Rippers can come as a single (single shank/giant ripper ) or in groups of two or more (multi shank rippers ). Ripping lets the ground surface rock be broken into small rubble easy to handle and transport, which can then be removed so grading can take place. Anand 1633851-civil
TYPES OF DOZER BLADES
SIZE OF BULLDOZER Size of bulldozer indicated by the dimensions of blade. Each blade has a capacity of hauling a particular type of earth & knowing the number of turns a bulldozer can be estimated. Each model of bulldozer has an operating range for blade size and adjustment. Larger machines have greater operating ranges than smaller machines. A larger machine can pitch and tilt deeper than a smaller machine typically. For heavy civil work , bulldozer blade widths can range from 80 to 220 and operating weights can range from about 7 tons to over 120 tons. Maximum digging depth ranges from about 1.50 to 2.50 Anand 1633851-civil
OUTPUT OF BULLDOZER O utput of bulldozers depends upon its operating condition. Output of all the earth moving machinery depends on given factors. FACTORS AFFECT OUTPUT OF MACHINERY a. Efficiency of operator b. Nature of soil c. Topography of area d. Type of equipment e. Weather Anand 1633851-civil
Bulldozer Productivity m3 / hour : Excavating only & haul in pile by dozer 75 HP (Horse Power), 15 meters haul, sand & gravel 43.5 m3 / hour Excavating only & haul in pile by dozer 75 HP (Horse Power), 15 meters haul, common earth 38.4 m3 / hour Excavating only & haul in pile by dozer 75 HP (Horse Power), 15 meters haul, clay earth 27 m3 / hour Multiply the dozer 75 HP productivity by 2.3 for dozer 200 HP Multiply the dozer 75 HP productivity by 13.44 for dozer 700 HP Anand 1633851-civil
Bulldozers are often used in road building, construction , mining, forestry, land clearing, infrastructure development, and any other projects requiring highly mobile, powerful, and stable earth-moving equipment. The bottom edge of the blade can be sharpened , e.g. to cut tree stumps. EARTHMOVING ( moving large amounts of earth and soil, used backhoe to lift everything and put it down somewhere else, sometimes as digging machines.) ROADBUILDING ( as a primary tool used in the building of roads) CONSTRUCTION ( Large construction projects require extensive preliminary site work, and much of this is done by bulldozers) DEMOLITION ( act of destroying and removing old and derelict properties usually involves the use of a bulldozer) U ses.. Anand 1633851-civil
F actors that affect the Selection of C onstruction Equipment's :- Economic factors: such as the cost of owning the equipment , fuel costs and operation. Besides consideration over resale value is also very important . Factors specific to companies : depending on the need of company for further uses like having many projects to do within that duration then they will provide the equipment's at heavy price/rates. But if there is a short term job work then they can provide it on rent. Factors specific to the jobsite : depending on sites topography. Factors specific to the equipment : The bigger the equipment, the more the investment and other considerations (its repair and maintenance) Project timeline considerations: if there's a limited time available for completion of project then company may avail advanced construction equipment's. Labour considerations: If there is a shortage of manpower at the jobsite, then the companies may opt for highly automated machines. Safety considerations: Any construction site is the locus of multiple high-risk activities. There are obvious safety concern s associated with workers operating on the ground Anand 1633851-civil
Bulldozers are large and heavy vehicles making them a good choice for demolition and clearing sites. Caterpillar tracks give bulldozers a distinct advantage allowing them to be surprisingly maneuverable for their extreme weight. The tracks are also quite wide which helps to distribute their heavy weight preventing them from sinking in sandy or muddy ground . Bulldozers are renowned for holding their ground which gives them phenomenal strength for pushing and dragging obstructions in their path . Some models of tanks can even tow up to 70 tons of weight and are used for moving written off vehicles and military purposes as well as in construction and demolition projects. Anand 1633851-civil
Repair and Maintenance Cost Repair and maintenance cost is incurred as the construction equipment is subjected to wear and tear due to the operations it performs . The repair and maintenance cost varies from one year to another over the service life of the equipment, however it increases with age of the equipment. The minor repairs can be carried out at the job site where the equipment is operating, however the major repairs can be carried out in the facilities set up by the equipment owner or in the workshop of authorized dealers for the equipment. The annual repair and maintenance cost can be calculated as a percentage of the annual depreciation cost of the equipment. The hourly repair and maintenance cost can be calculated by dividing the annual cost by the number of operating hours per year. The repair and maintenance cost includes.. T he cost of replacement parts, L abor charges and The cost of setting up and operating facilities to carry out major repair and maintenance operations .
Points to be watched when Supervising Works Loads – Fully heaped blade Engine Speed – Full rpm / full capacity Travel – 1 to 8 km/ hr , haul distance- 60 to 90m etc. Spreading – Time being wasted? Mechanical – All adjustment to power unit maintained General – Right machine for job? Right operator? Right procedure? Machine proper maintained? Anand 1633851-civil