Theme 12 - Lift engineering

Question 1

OH&S Act def of lift:

Answer 1

Permanent installation
Installed in shaft
Runs on fixed guide
Serves landings
Conveyance of people/ goods

Question 2

Uses for lift shaft/ motor room

Answer 2

Lift equipment/ equipment directly associated with lift

Question 3

Most common lift categories

Answer 3

Traction (rope/ belt; AC/ DC drives)
Hydraulic (limited to few floors)

Other special lifts:
Chain
Water
Steam
Rack & pinion

Question 4

Machine room above (MRA) lift

Answer 4

Lift controls & machine are installed in room that is separated from lift shaft

Question 5

Machine room less (MRL)

Answer 5

Majority of lift controls & machine is installed in upper space within shaft

Latest improvements allow lift for buildings up to 30 floors.
Speed restriction from manufacture to manufacture.

Question 6

Types of machines used:

Answer 6

Geared roped traction
Gearless roped traction
Geared belt drive

Question 7

Geared AC motor traction lift

Answer 7

lift car is raised & lowered by steel cables driven by geared reduction unit.

Midrise/ mid speed

Commercial buildings 9 floors/-
Residential buildings 18 floors/-

Question 8

Gearless AC motor traction lift

Answer 8

lift car is raised & lowered by steel hoist cables driven directly by large-frame AC motor.

High rise/ high sped >1.75 m/s

Commercial buildings 9+ floors
Residential buildings 18+ floors

Question 9

Geared DC motor traction lift

Answer 9

lift car is raised & lowered by hoist cables driven directly by smaller-frame DC motor

Low/ mid rise buildings
Speed <= 1,75 m/s

Commercial buildings under 9 floors
Residential buildings up to 18 floors

Question 10

Gearless DC motor traction lift

Answer 10

lift car is raised & lowered by hoist cables driven directly by large-frame DC motor

High rise/ high speed > 2,5 m/s

Commercial buildings over 9 floors
Residential buildings over18 floors

Question 11

Gearless AC motor belt traction lift

Answer 11

lift car raised & lowered by specially designed belts driven directly by small-frame AC motor

Low & mid rise/ speeds up to 1,75m/s

Question 12

Steel rope vs belt

Answer 12

Steel rope = no limitation in application

Belts = limitation applicable
*speed
*height of building
*load capacity

Question 13

Hydraulic lifts requirements

Answer 13

• Transportation of passengers/ goods
• buildings 5 floor/-
• slow speed operation of <= 1 m/s
• low/ intermittent usage
• space restriction apply

Question 14

Hydraulic lift

Answer 14

lift car raised & lowered by hydraulic ram, driven by piston mounted inside a cylinder pumped with fluid (hydraulic oil)

Low rise/ special applications