Elevators and Escalators

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Good reference material on Lifts and Escalators for students of Architecture.Prof.S.G.Bhate.

Transcript of Elevators and Escalators

ELEVATORS AND ESCALATORS

OF THE DECISIONS THAT MUST BE MADE by the designer of a multistory

building, probably none is more important than the selection of the vertical

transportation equipment-that is, the passenger, service and

freight elevators and the escalators. Not only these items represent a major

building expense being in the case of a 25-story office building as much as

10% of the construction cost, but the quality of elevator service is also an

important factor in a tenants choice of space in competing buildings.

MOVEMENT PATTERN

VERTICAL– ELEVATORS – LIFTS

INCLINED – ESCALATORS – MOVINGSTAIRS

HORIZONTAL– CONVEYORS -- WALKWAYS

HYDRAULIC TRACTION

ESCALATORS

MULTI LEVEL

ECSALATORS

HYDRAULIC

TRACTION

COMPONENTS OF GEARED ELEVATOR INSTALLATION

COMPOSITE HOIST MOTOR AND SHEAVE ASSEMBLY

PASSENGER ELEVATORS

ONE MUST DIFFERENTIATE BETWEEN

1) RESIDENTIAL HIGH RISE

2) ELEVATORS IN NORMAL OFFICE BUILDINGS

3) ELEVATORS IN SMALL OFFICE BUILDINGS AND

4) ELEVATORS IN TALL OFFICE BUILDINGS

THE ELEVATOR PLANNERS JOB IS TO

1) DETERMINE REQUIRED CAPACITY

2) CALCULATE THE NUMBER OF ELEVATORS NECESSARY

3) DEMANDS ON ELEVATORS TO BE CLEARLY DEFINED

BUILDING PARAMATERS

BASIC PARAMETERS FOR ELEVATOR TRAFFIC CALCULATIONS

1) FOR OFFICE BUILDINGS--- THE PLANNED OFFICE SPACE

2) FOR HOTELS --- THE NUMBER OF HOTEL ROOMS

3) FOR RESIDENTIAL BUILDINGS--- THE NUMBER AND SIZE OF APARTMENTS

OFFICE SPACE OR THE NUMBER OF HOTEL ROOMS OR APARTMENTS MUST BE DETERMINED FOR EACH FLOOR

THE NUMBER AND HEIGHT OF INDIVIDUAL FLOORS MUST BE KNOWN

USABLE FLOOR SPACE

NUMBER OF PASSENGERS

THE POPULATION OF EACH STORY IS DETERMINED BY THE USABLE FLOOR

SPACE . THE FOLLOWING VALUES CAN BE CONSIDERED

--- OFFICE BUILDING WITH ONE USER

8-10 SQMT NET AREA / PERSON

--- OFFICE BUILDING WITH MULTIPLE USER

10-12 SQMT NET AREA / PERSON

--- RESIDENTIAL BUILDINGS AND HOTELS

1.5-1.9 PEOPLE / ROOM

OR WITH SLIGHT DEVIATION

--- RESIDENTIAL BUILDING

13 SQMT / PERSON

--- HOTEL

1,5-1.7 PEOPLE / DOUBLE ROOM,

1 PERSON / SINGLE ROOM

--- RESIDENTIAL BUILDING

DEPENDING ON APARTMENT SIZE- 2,3 OR 5 PEOPLE/ APARTMENT

REQUIRED HANDLING CAPACITY

THE TOTAL PROBABLE MEAN OCCUPANCY FOR EACH FLOOR IS USED TO

DETERMINE THE NECESSARY CONYENCE CAPACITY OF EACH ELEVATOR

GROUP DURING IN- RUSH PERIOD

THE TRAFFIC MODEL CALCULATIONS ARE BASED ON THIS PERIOD BECAUSE

DEMANDS ON THESE TIMES CAN BE STANDARDIZED AND COMPARED

ELEVATOR PARAMETERS

FIVE MINUTE HANDLING CAPACITY

THE No.OF PEOPLE TRANSPORTED IN FIVE MINUTES

FOLLOWING ARE THE STANDARD TRAFFIC %

OFFICE BUILDINGS WITH SEVERAL USERS---11-15%

OFFICE BUILDINGS WITH ONE USER---17%

WITH HIGH PRESTIGE--- 17-25%

AVERAGE WAITING TIME

OFFICE BUILDING WITH PRESTIGE---20-25 SEC.

OTHER BUILDINGS---25-30 SEC.

RESIDENTIAL AND HOTELS---40-100 SEC

CAB CAPACITY

THE NECESSARY FLOOR AREA IS CALCULATED USING THE No. OF PASSENGERS TO BE TRANSPORTED EACH RUN TO ACHIEVE THE DESIGNATED HANDLING CAPACITY WITH GOOD AVERAGE WAITING TIMES.

A NET FLOOR AREA OF AT LEAST 0.22 SQMT/ PER. IS DESIRABLE

TIME LOST AT STOP

THE TIME LOST AT STOP IS THE TIME DIFFERENCE BETWEEN A TRIP

FROM FLOOR A TO FLOOR B WITHOUT INTERVENING STOPS AND A

TRIP FROM B TO A WITH ONE INTERVENING STOP, PLUS A DEFINED

DOOR OPENING

SPEED

ELEVATOR SPEED IN HIGH- RISES IS DEPENDENT ON HOISTING HEIGHT AND CHOSEN ON THE BASIS OF TRAFFIC CALCULATIONS.

FAST ELEVATORS REQUIRE COMPLEX EQUIPMENT FOR THE DRIVE

MECHANISM, CARS, AND COUNTER WEIGHT DESIGN, BUFFER AND

TENSION SHEAVE IN THE SHAFT PIT; THEY NEED COSTLY MEASURES

TO ENSURE STRUCTURE AND AIR BORNE NOISE INSULATION AND

THEY HAVE A VERY HIGH ELECTRICITY CONSUMPTION

HIGH RISE ELEVATOR GROUPS

ELEVATOR GROUPINGS

ELEVATOR ZONING

ESCALATOR DIMENSIONS

ESCALATOR DIMENSIONS

ESCALATOR GROUPINGS

CRISS CROSS ARRANGEMENT

PARALLEL ARRANGEMENT

PRINCIPAL COMPONENTS OF THE ELEVATOR

The car

is a cage of some fire resistant material supported on a structural frame

The cables (ropes)

are connected to the cross-head (top beam of the elevator} and carry the weight of the car and its live load are made of groups of steel wires

The counterweight

is made up of cut steel plates stacked in a frame attached to the opposite ends of the cables to which the car is fastened.

The elevator machine

turns the sheave and lifts or lowers the car. It consists of a heavy structural frame on which are mounted the sheave and driving motor

The shaft or hoist way

is the vertical passageway for the car and counterweights

Advantages of Hydraulic types of elevators.

1. From the point of view of architecture and construction the major inherent

advantage of hydraulic units is the absence of an overhead machine

room, a penthouse, and traction equipment.

2. The elevator load is carried by the ground and not the structure. By

contrast, traction units place a large structural load on the pent house

and machine room floors and on overhead steel as well.

3. The hoist way is smaller due to the absence of a counter weight and its

guide rails.

4. Cars can be lowered manually by the operation of oil valves. This is

particularly useful and important in the event of control equipment failure

or power failure.

5. There is essentially no limit to the load that can be lifted.

Disadvantages of Hydraulic types of elevators.

1. The Major inherent disadvantage of the hydraulic elevator is its operating

expense. Because it is not counter weighted, it requires a relatively large

motor to drive the oil pump, and all the energy is lost in heat.

2. They are limited to low-rise, low-speed applications.

3. Ride quality is inferior to that of a good traction unit, although it is entirely

acceptable to residential, mercantile, and industrial applications.

4. Because oil viscosity changes with temperature, the ambient temperature

of the space containing the pump and the oil storage tank must be

controlled to maintain ride quality and performance. The high inrush

current taken by the pump each time it starts, which is every time the

elevator travels upwards, require a stiff power supply to avoid problems of

light flicker and other undesirable line voltage fluctuations.

5. Noise from the pump and motor plus piping noise can be disturbing. This

problem can be ameliorated by moving the pump mechanism (up to 50 ft

from the elevator shaft)