Telescopic crane

Post on 12-Jul-2015

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• These are truck cranes that have a self contained telescoping boom.

• Telescoping boom contains a number of tubes fitted one inside other.

• Can travel on public highways.• Once the crane is leveled at the new worksite it is ready to

work without setup delays. • If job require crane utilization for few hours to a couple of

days, telescopic crane should be given first consideration because of it’s ease of movement.

Introduction

Manufactures

• Porclain • JCB• Escorts• ACC• Hitachi• Rolex• Hyundai• Apex• Ace

Work CycleLoading

Elevating

SteeringDriving

Unloading

Working Principle

A B

L L

• To lift the load A, force B should be applied at equal distance on the other end.

(B>A)

AB’

L l

Concept in cranes• In cranes, the force A is the load to be lifted.

• Force B is the force applied i.e. counterweight.

(counterweight also contains fixed pulley block on which the cable is wrapped)

• The pulley system delivers a force to the load that is equal to the applied force multiplied by

the length of cable (boom) between the load lifted and counterweight.

• This is known as Mechanical advantage.

• So we can say that, load lifting capacity of any crane depends on the length of the boom.

Specifications Extension boom

Fixed boom

Cable

Counterweight

Hook

hydraulic

Cabin

Outrigger

Dimensions

Machinery

Operation cycle timing

• Boom Raising : 27 sec.

• Boom Lowering : 20 sec.

• Telescopic In : 8 sec.

• Telescopic Out : 14 sec.

• Hoist Line Speed : 52 m/min.

• Steering : 7 sec.

EconomyBefore using or buying an equipment owner should answer two question??

1- how much does it cost to operate the machine on a project ?

2- what is the optimum economic life and the optimum manner to secure a machine ?

The reason to purchase an equipment maybe to generate profit .

• Upon deciding there are two costs associated the construction equipment

• ownership cost

• Operation cost

• Generally know as O&O costs

• Suppose $90/hr and a production of 300 tons/hr so production cost would be $90/h/300 tons /hr

Problem

14

Telescopic crane costs 325000 USD service life is 15 years Per hour ownership cost = 2.471 USD each year it should work= 2500 hours Yearly ownership= 2166.32 USD

Rental Duration Rates Hours Rental Rate $/hr Operating hours Break even 2166.32 point

Operating hour break even point6500/hr

Monthly 6500 216 30 72 -

Weekly 2500 83 30 72 216

Daily 695 23 30 72 216

Rental options Monthly: 6500 USD Weekly: 2500 USD Daily : 695 USD

Ownership cost• Purchase expense

• salvage value

• tax saving from depreciation

• Major repairs and overhauls

• property taxes

• insurance

• Storage and miscellaneous

Operating cost

• Fuel

• Lubricant, filters and grease

• Repairs

• Tires

• Replacement of high-wear items

Thank you