2. PREPARATION OF EQUIPMENT SCHEDULE
This schedule is prepared before the project is started to establish the
types, quantities and dates on which equipment will be needed, so that it may
be arranged as and when required. This is also prepared with the help of
construction schedule. The aim of this schedule is to derive maximum
advantage of the equipment when at site and remove it from the site when its
job is over this will save money.
4. CLASSIFICATION OF CONSTRUCTION EQUIPMENTS
The construction equipments may be classified as
a) Excavating equipments
Trenching machine, etc.
36. Selection of equipment's
• The various factors to be considered, while selecting the
construction equipment are as follows:
• Standard Type of Equipment's:
• The contractor should confine their purchase to standard
equipment unless a project definitely justifies the purchase of special
• Replacement of Parts: Prior to purchasing equipment's, the
buyer should determine where spare parts are obtained.
• If the parts are not obtainable quickly, it may be wise to
purchase other equipment, for which the parts are quickly
available, even though the latter seems less desirable.
38. Selection of Equipments
• Operating Costs:
• The most efficient and therefore the most economical
equipment is one whose operating cost is the minimum.
This is a full proof measure for selection of the equipment.
• Utilization of Equipment's:
• The maximum utilization of the existing machine should
be done to reduce the cost of production of various items of
39. Selection of Equipments
• Availability of Equipment: Sometimes the
selection of equipment has to be made from the
available equipment held with the
manufacturers or dealers.
• Source of Equipment: Contractor and other
users of construction equipment frequently are
concerned with a decision as to whether to
purchase or rent (Lease) equipment's.
40. Selection of Equipments
• Country of Origin:
• As far as possible, indigenous equipment's should be used. This
encourages the industry of the country and saves foreign
exchange. When imports have to be resorted to, they should
be preferable restricted to soft currency area.
• Operating Facility:
• The equipment's chosen for project should be such that the
trained operators for the machine are available.
• Suitability of Equipment for Future:
• While selecting an equipment, the useful life of the
equipment should be compared with the duration of the
project. If the life of the equipment is longer, it should be
possible to use the equipment for other projects.
41. Classification of equipment's
• Depending upon their availability, commercial
sizes and specifications, the equipment's can be
classified into following types:
• (i) Standard Equipment's
• (ii) Special Equipment's
42. Classification of equipment's
• Standard Equipment's:
The standard equipments are commonly manufactured
and are easily available to the prospective purchasers.
• They can be used for variety of construction operations
without any difficulty and they are available in standard
commercial sizes. The initial investment is less as
compared to a special equipment.
• The delivery of standard equipment's is very quick, as it is
readily available in the market.
• The repair parts for standard equipment can be obtained
more quickly in short period.
45. Classification of equipment's
• Special Equipments:
• The special equipments are those which are
manufactured for a specific project or which does not
have readily accessible spare parts.
•The selection of special equipment's should be made
carefully after proper financial analysis.
•The initial investment in case of special equipment
is very high and there is risk of change in design, it
cannot, be used economically on the other project.
47. Special Equipments
•A special order is to be given to the manufacturer of
special equipment's and a special price is to be given
and therefore the delivery of special equipments can
be obtained after long period.
•Examples of special equipment include tunnel-
boring machines, large hauling units and very large
shovels, such as a 70 to 80 cubic metre shovel used to
49. Factors affecting Cost of Owning operating Equipment:
▪ Cost of the equipment delivered to the owner
▪ Demand of the equipment at the end of its useful life
▪ Number of hours it is used per year
▪ Number of years it is used
▪ Severity of conditions under which it is used
▪ State of maintenance and repairs
50. ▪ DepreciationCost
▪ InvestmentCost (Average investment = )
• Maintenance and repair Cost
• Operation Cost (Repair charges, Depreciation on tyres and tubes, Labour
Charges, Fuel Charges, Operators and maintenance crew charges,
• Down time Cost
• Obsolescence Cost
• Replacement Costs
Costs to be considered for owning and operating
• Depreciation can be defined as the loss or decrease in the
value of the property due to the use, life, wear and tear,
decay and obsolescence.
• As the equipment which is purchased today will not work
for ever. This may be due to wear and tear of the equipment
or obsolescence of technology.
• It is dependent on its original condition, quality of
maintenance & mode of use.
• Usually a % of depreciation per annum is allowed, which
gradually increases with time.
• Present value of property= Initial cost - Total amount of
52. Types of depreciation
a) Physical depreciation
1.Wear and tear from operation
2.Action of time and other elements
b) Functional depreciation
1.Inadequacy or suppression
53. Methods of Calculating Depreciation:
1. Straight Line method
2. Constant Percentage method
3. Sinking Fund method
4. Quantity Survey Method
54. Straight Line method
Assumption: Property loses its value by the same amount every year.
Therefore, Annual Depreciation= Annual Decrease in property value
where, D= Annual Depreciation
C= Original Cost
Depreciation of property after m years:
S= Scrap Value
n , m= life in years
Therefore, Book value after m years:
55. Constant Percentage method
Assumption: Property will lose its value by a constant percentage of its value at
the beginning of every year.
Where, p= % rate of annual Depreciation
S= Scrap value C= Original cost
n= life in years
If any age of property is m years, the value of property after m years:
56. Sinking Fund method
▪ Assumption: Depreciation of the property = the annual sinking fund +
interest on the sinking fund for that year.
▪ If i is the rate of interest, the annual sinking fund installment(p) to
accumulate 1 Rs in m years:
If i is the rate of interest, and 1 Rs is deposited every year, total sinking
fund accumulated at the end of n years:
▪ Rate of depreciation in n years:
57. Investment cost
Investment (or interest) cost represents the annual cost
(converted into an hourly cost) of capital invested in a machine. if
borrowed funds are utilized for purchasing a piece of equipment,
the investment cost is simply the interest charged on these funds. if
it is purchased with company assets, an interest rate that is equal to
the rate of return on company investment should be charged.
Maintenance and repair costs
The cost for maintenance and repairs include the expenditures for
replacement parts and the labor required to keep the equipment in
good working condition.
The manufacturers of construction equipment provide information
showing recommended costs for maintenance and repairs for the
equipment they manufacture. The annual cost of maintenance and
repairs is often expressed as a percentage of purchase prices or as a
percentage of the straight-line depreciation costs.
Operating cost is incurred only when the equipment is operated. The
operating cost of the equipment is influenced by various parameters
namely number of operating hours, location of job site, operating
conditions, category of equipment etc. The operating cost consists of
a) Repair and maintenance cost,
b) Fuel cost,
c) Cost of lubricating oil, filter and grease,
d) Tire cost
e) Equipment operator wages,
f) Cost of replacing high-wear items and
g) Cost of mobilization, demobilization and assembly.
Down time cost
It is a time that a machine is not working ,because it is undergoing
repairs or adjustments.
It may be defined as the loss in the value of an equipment due to
improvement in designs of equipments.
Every year the cost of equipment is increasing. In view of these
factors, they are to be included in ownership cost which will allow
the unit of equipment to generate sufficient capital during its
economical life to ensure its replacement at the end of the
61. Economic life of Construction Equipment's
Equipment should be replaced under following circumstances:
4. Normal Deterioration
63. RIM PULL
The rim pull of tractor at any speed in the force between the tyres of the
driving wheels of the tractor and the surface on which the tractor travels is
called rim pull. It can be calculated by the following relation.
375 x efficiency x h.p. of tractor
1. F.P.S. system, Rim pull Lb
Speed in miles per hour
2. M.K.S. system, Rim pull = Kg
275 x efficiency * metric h.p.
Speed in km p.h.
64. The pull exerted on the trailing load = Rim pull - rolling resistance - grade
resistance - trailing load. Thus the pull depends upon the traction of the surface
of travel and the weight of the tractor.
In case of a crawler tractor, the equivalent pull rating is equal to the
drawbar pull. This is the net hauling force which a crawler tractor can exert
on a trailing load.
Drawbar h-p can be calculated from drawbar pull and speed as follows
For f. p. s. units drawbar =
Where p is the drawbar pull in lbs. and, v = speed in feet per minute
p x v
It is defined as the maximum slope expressed as a percent, up to which a Wheel
type prime mover or a crawler may move at a uniform speed. It may be
determined for a loaded or empty vehicle. Thus the Gradability of a tractor
Only will be greater than for a tractor that is pulling a loaded vehicle.
Gradability nay be specified for any desired gear. The Gradability for a loaded
or an empty vehicle is different.
k = Gradability %
G - Total gear reduction for particular gear selected.
T = Rated engine torque, kg. cm.
R = Rolling radius, the radius of the loaded driving wheels in cm
N = Rolling resistance, kg/ton W = Gross weight of complete unit, kg.
Gradability can be given by =
Advantages of two wheel type tractor
1. Higher tractive force is available.
2. Increased maneuverability
67. INSPECTION AND TESTING OF EQUIPMENT
To keep the machines in proper working condition, periodical inspection
of machines is necessary. Periodical inspection is helpful in avoiding major
defects in machines, reducing maintenance and repairs costs and reduces
Accidents. Usually big construction companies have their own workshop for
the repair and maintenance of machines. The workshop decides the dates for
inspection of various equipments engaged on a project, and the machines are
sent on workshop on decided dates for inspection.
Usually all machines are inspected after every three months Inspection
is done by skilled technical team. Worn-out parts of machine are replace.
Engine performance and machine output is also checked during inspection.
After each inspection the machine is graded, and the causes of low grading are
68. MAINTENANCE AND REPAIR
Repair and maintenance of machines is necessary to get effective output
of machines and successful progress of the project. To prevent breakdown of a
machine regular periodical inspection and maintenance should be carried out.
If machines are maintained daily or weekly and inspected by workshop team
after every three months, then such machines will hardly breakdown. To avoid
accidents, machines should be handled carefully. This type of maintenance
which keeps the machine in safe working condition is called preventive
69. REQUIREMENTS OF PREVENTIVE MAINTENANCE:
The driver should possess necessary skills.
The machine should have sufficient workshop cover.
There should be satisfactory arrangement for speedy worn-out parts.
Daily maintenance like machine washing, cleaning, nut-bolt tightening
etc. should be done.
Weekly maintenance like machine washing, cleaning, oil level checking,
tyre pressure checking, distilled water level of battery should be done.
Three monthly inspection by the workshop team should be done. The
machine grading is done and its efficiency is compared with the
70. TYPES OF MAINTENANCE
The main types of maintenance are
A. Daily maintenance
B. Weekly maintenance
C. Monthly maintenance
D. Quarterly maintenance
71. A. Daily maintenance :
Washing of a machine
Removing dust and dirt
Tightening nut & bolt
Daily maintenance of a machine is carried out after its usual working hours.
B. Weekly maintenance
Washing a machine cleaning a machine
Tire pressure checking
72. MACHINE REPAIRING
In big construction projects, two type of workshop are provided.
A. Base workshop
B. Field workshop
The main functions of base workshop are
o To make arrangement for the purchase of new machine.
o Repair of B.L.R. (Beyond Local Repair)
o Dispose off B.E.R. (Beyond Economical Repair) machine
73. Field Workshop:
It provides repair cover to all the machine of a project. Field workshop is a
mobile workshop. When any machine comes under breakdown, the field
workshop team reaches the site for repair.
The base workshop should have the following sections:
1.Machine and fitting shop
3.Blacksmith, welders, structural shop
7.Erection, assembly, track shop
9.Receipt and issue
74. SAFETY WITH MACHINES
The following precautions should be taken to avoid accidents due to machines
1. A machine should be inspected before starting. Fuel, oil, hydraulic level
must be checked.
2. A machine should be cleaned regularly. Windows and foot pedal should be
3. Fire extinguishers, first - aid box should be kept with machines.
4. The machine should not run at over speed and it should not be over loaded.
5. The possible causes of accidents and their remedial measures should be
thought of in advance.
6. The front glass of machine should be kept clean.
75. 7. The communication system to be used while operating machine should be
learn in advance. Hand communication is preferred.
8. Before starting machine, it’s all controls should be checked as per
9. Warning tags near main start switch and other controls should be checked.
10. The machine should be properly ventilated. Proper arrangement shall be
made for the protection against smoke.
11. Machine tools shall be kept in a machine tool box.