PDX_31_Specialties / Conveying Systems Flashcards
ANSI/ASME code A17.1
Safety code for elevators, dumbwaiters, escalators, and moving walks
American industrialist who invented the safety device that prevents elevators from following is the hoisting cable fails
Elias Otis
NFPA
Fire safety and electoral standards for life safety
National elevator industry Inc. (NEII)
Standard layouts and suggested minimums for accessibility
1.6 x building height + 350 =
Elevator speed
Stairs may be as narrow as__but when loads are over 50 people, they must be__wide:
36 inches minimum,
44 inches minimum, 50ppl +
Max stair rise, min stair run:
7” max rise, 11” min run
Nosings have a maximum rounded edge of
Half-inch
Hey drill diameter between__and at least__away from wall:
Diameter 1-1/4” – 2”
Min 1-1/2” clr from wall
Ramp slope, Max rise, Max run, landing dimensions
Minimum 1:12
Max rise of 30”
Max run 30’
60” landing
Minimum ladder width
18 inches wide minimum
– Used for lowrise or less than five story buildings, about 50’0”.
– Speed varies between 25 – hundred and 50 ft./m
– Carrie about 10 tons
– Freight
– Cylinder extends as far into the ground as it is tall (So they don’t require penthouse Machine room or heavily braced roof over shaft.
Hydraulic elevator
Uses a telescoping plunger set into the shaft next to the cab. Lift is provided by applying force to the upper member of the car frame.
Holeless hydraulic
– Commercial/industrial greater than five stories/50’0”
– Up to 1800 ft./m
– Up to five times
Electric (traction ) elevator
Counterweights in electric elevator weigh:
The weight of an empty car + 40% of live load capacity
Electric elevators use gears when
High-speed installation
New motor and break on one shaft which drives a second main shaft
Electric elevator double wrap:
Cables Passover the sheaves twice, get worn out faster, used for high-speed elevators where more traction is required
When the rope is wrapped around achieve on the counterweight and connected to the top of the shaft the rope moves twice as fast as the car, but requires less wait to be lifted.
1:2 roping
Freight elevator speeds range from:
50 ft./m to 200 ft./m
Mounted on shaft and operated by the control mechanism. Self applying so the car will stop in the event of a power failure.
Main break
Measures and limits the elevator speed by means of the control panel. It will actually the safety rail clamp if the elevator tries to exceed its proper rate of travel.
governor
Grip the sides of the rails if there is an emergency
Safety rail clamps
Located on the bottom to stop the car if it over travels at low speed… Won’t do much to stop a car traveling at a higher speed
Car buffers/bumpers
Prevent the elevator from operating in less the horse toy door is closed and locked
Interlocks
Doors have spring-loaded lip that retracts open if it encounters a person/object when attempting to close
Safety edged
Similar to save the edges, but senses the presence of a person near the door and can stop the closing motion.
Proximity dictators
Common door arrangement which allows faster passenger loading in unloading
Single speed center opening
Two door leaves, one which telescopes past the other as they move
Two speed side opening
Four door leaves, to telescope pass the others as they move
Two speed center opening
Elevator door width
Minimum opening with is 3’6”, but 4’0” is better because it allows two people to leave or enter at the same time.
Best located directly above the hoistway to provide adequate space for motor, sheave, break, controller board, speed governor, floor selector mechanism, and motor genitor.
Machine room
Machine room should have these dimensions:
As wide as the hoistway and 12’ – 16’ deeper.
Min ceiling height 7’6” – 10’0”+
Best system for new, high-quality installations of any speed elevator:
Variable voltage, variable frequency AC
Motor control system
Platform can be 9 ft.² maximum and carry 500 pounds
Dumbwaiter
Used to move large numbers of people quickly, efficiently, safely, and I don’t low-cost of operation:
Escalators
4000–8000 people per hour
Typical inclination of escalator:
Typical width of escalator and escalator treads:
30°
32” or 48” wide
w/ tread widths 24” or 40”
Not considered a legal exit or ADA route
Escalator
Escalator industry standard speed
100 ft./m industry standard,
120 ft./m for transportation and sports facilities
Up and down escalators “side-by-side or separated by distance quote, seen often and metro stations and multilevel motion picture theaters
Parallel configuration
Minimize the structural space required by “stacking” escalators that go in one direction, frequently used in department stores or shopping centers:
Crisscross configuration
Moving sidewalks can have a short incline up to __, and have typical operation speeds of __.
Short incline up to 15°.
Speed of 140–180 ft./m
Should never be more than___cars in one elevator bank or___cars in one line.
Eight cars in one bank, or four cars in one line.
Maximum number of cars serving the same portion of the building in a single hoistway, per the IBC
3 cars in same hoistway
Typical elevator strategy in very tall building:
– Divide the total number of required elevators into banks that serve different zones. (Shafts take up a lot of space especially on lower floors)
– Sky lobby concept: high-speed elevators from lobby to sky lobby, transfer two elevators serving specific upper floors.
– Stacked or double deck elevators: doubles shaft capacity, reducing area required for elevator and decreases local stops
Maximum number of passengers that can be handled in a given. Typically based on a five-minute peak
Handling capacity
Measured and weighed the number of people a car can carry
Capacity
Average time between departure of cars from lobby
Interval
Average time required for an elevator car to make a round trip
Road trip time
Average time spent by passenger from the moment they arrive in the lobby to leaving the car on the upper level
Travel time
Average waiting time for an elevator, varies with building type
Interval
Blue six pointed star with the rod of Asclepius in the center, used to represent emergency medical services
Star of life
Total # ppl in 5 min period
/ handling capacity of one car
of elevators required
Small buildings, single call button each floor, single button for each floor inside car. Pastor has the exclusive use of the car until the trip is complete:
Single automatic
Most common type of system for light to moderate service. Elevator remembers and answers call in opposite direction. One trip is complete, the cab returns to lobby.
Selective collective operation
Large buildings, system controls all elevators with programmable microprocessor to respond to calls in the most efficient way.
Group automatic operation
Elevator emergency operation:
Power failure: one car can operate at a time, other stop, allowing unloading. Fire: return to lobby without stopping, switch to manual mode by FD
If building is over for stories and has at least one elevator, which must be able to hold a 24” x 84” open stretcher
Star of life
Minimum ada dimensions of the center opening car
80” x 54”with 42” door min
60” x 60” with 36” door min
Minimum ADA dimensions for elevator car with side door:
68” x 54”
54” x 80”
Both 36 inch door min
