Elevators and Escalators
December 5, 2016 | Author: shrikant | Category: N/A
Short Description
Good reference material on Lifts and Escalators for students of Architecture. Prof.S.G.Bhate....
Description
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 USABLE FLOOR SPACE 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
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)
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