lift
TRANSCRIPT
LIFT
lift• For multi- storeyed buildings the installation of lifts is a
must to avoid fatigue in climbing up the stairs and for quick vertical circulation between different floors.
• The provision of lifts in a building is a highly specialised job.
• A vertical hat with openings at the floor level is provided.
• The shaft is located at a suitable place e.g. by the side of the stair or within the open well of a stiar.
• The shaft extends below the ground floor to accomodate the spring buffers for low speed lifts and hydraulic buffers high speed lifts.
• Usually a machine room (control room) is located at the top of the left shaft for housing equipment and accessories.
• It can be at the bottom by the side of the shaft.
• The size of the machine room is normally 4 m x 3 m x 2.5 m.
• Floors or machine room should be designed to carry a load or not less than 500 Kg/m
• Previously collapsible doors were provided both for the lift car (cage) and for the opening in the shaft at the floor level.
• Now a days flush doors of sliding type are provided.
Types of lift
1) Hydraulic lift
2) Electric lift
3) Passenger lift
4) Goods lift
Components of lift
1) Control room
2) guides
3) lift car
4) counter weight
5) control panel
6) lift pit
7) Buffer
8) Hoist way
9) hoist rope
Space Requirements
Passanger lift
DESIGN CONSIDERATIONS FOR LIFT
• Two important aspects in lift design are
a. Quantity of service
b. Quality of service
a. Quantity of service
• “Quantity of service” means passenger handling capacity of lift.
• During peak hours, the number of passengers which a lift can handle in 5 minutes time is taken as passenger handling capacity (H).
• It is expressed as percentage of total number of persons living in the building.
Class of occupancy H (percent)
Residential building
Office for single purpose
Office for multiple purpose
5
15 – 25
10 - 15
b. Quality of service
• The waiting time for lift by passengers on different floors is expressed as quality of service.
Quality of service(WAITING INTERVAL)
RATING
20-25 Seconds
30-35 Seconds
35-40 Seconds
40-45 Seconds
over 45 Seconds
Excellent
Good
Fair
Poor
unsatisfactory
Handling capacity
H= 300 x Q x 100
T x P
Where,
H = Handling capacity for 5 minute
Q = average number of passengers carried in car
T = waiting interval (sec.)
P = total population to be handled
Waiting interval
T = Rf
N
where,
T = Waiting interval (sec.)
Rf = Round trip time
N = No. of lifts
Occupant load :
Occupant load = gross area (m2)
person
Sr. No.
occupancy Occupant load gross area in m2 / person
1.
2.
3.
4.
5.
6.
7.
Residential
Educational
Institutional
Assembly hall with seats
Business and industrial
Storage
hazardous
12.5
4
15
0.6
10
30
10