Article 4- Escalator Parts & Definitions

Introduction of Escalator Parts and Definitions 

In this article, we intend to introduce the escalator parts and definitions which are useful and practical. 

1. Authorized Person

The authorized person is a Professional, trained individual with approval to reach restricted areas of escalators and moving walks (machinery spaces, separated machine rooms) and to work there with the purpose of assessment, testing, and support.

2. Competent Person

A competent person is an individual with the required technical knowledge, skills, qualification, and experience to perform a specific job or task.

3. Capacity

The capacity is the maximum traffic flow of passengers transferred at optimal conditions per hour by escalators or moving walks.

4. Angle of Inclination

The angle of inclination is the angle at which the inclined section of the escalator and moving walk meets with the horizon.

5. Elevation Height 

The elevation height is defined as the level difference between two finished floor surfaces.

6. Horizontal Length

The Horizontal Length is measured based on the elevation height of the escalator and moving walk. After choosing the appropriate angle, in accordance with the formula for each angle, the horizontal length will be determined. It is equal to the horizontal distance between two construction beams, located on the lower and upper floors.

7. Nominal Speed

The nominal speed is the speed of the moving steps and pallets without load which must be equal to or less than the authorized speed.

8. Supporting Structure (Truss)

The truss is a chassis composed of different steel profiles on which all the machinery is installed. The truss is divided into three parts “upper section, middle section, and Lower section”. 

9. Truss Soffit

The Truss soffit is a steel plate installed on the underside of the truss. 

10. Truss Support Angle

The truss support angle is an angle steel profile which allows the escalator to rest on the construction beam of the building.

11. Middle Support 

For the escalators with high elevation height and long horizontal length, middle support(s) should be considered to prevent deflection in the inclined section of the escalator or moving walk.

12. Track System

The track system guides the step wheels and step chains in a circular movement inside the truss of the escalator. The track system is divided into three parts: “Upper track, Inclined track, and Lower track”.

13. Transition Radius

Transition Radius is the curvature radius of the upper and lower parts of the track system.

14. Machinery

Machinery involves all the parts, components, equipment, etc. which cause the device operation.

15. Machinery Spaces

Machinery spaces are internal or external spaces of the truss where parts or all the components are installed.

16. Step or Pallet

The step or pallet is a part on which the passengers stand. A step has horizontal and vertical plates, like stairs used in escalators, but a pallet has only a horizontal plate which is laid beside each other and used in moving walks.

17. Step/Pallet Width

The width of the step or pallet on which the passengers stand and must be in compliance with the standard.

18. Step Demarcation Cleat

Step demarcations are yellow strips on the edge of the step tread surface which are painted or made of plastic and are designed to show the passengers the safe area to step on.

19.  Step Trailing Roller

Step trailing rollers are two rollers installed under the step located on the tracks.

20. Step Guide Roller 

The step guide roller is a device to adjust the distance between the steps and the skirt panel.

21. Horizontal Steps 

For the passengers’ safety, there must be a number of horizontal steps in both landings so that the passengers can keep their balance before the steps start the inclined movement.

22. Comb

The comb is a toothed part installed at both landings and meshed with the grooves of the step tread surface.

23. Comb Plate

The comb plate is a platform on both landings on which the combs are installed.

24. Comb Illumination

Comb illumination is lighting installed on the skirt panels to lighten the comb area on both landings so that the passengers can have more safety while entering and exiting.

25. Floor Plate

The floor plate is a platform surface located on both landings which are installed next to the comb plate; it also acts as the machine room cover.

26. Handrail

The handrail is a moving rubber belt, located on the balustrade for the passengers to hold and keep their balance on the escalator or moving walk. 

27. Handrail Frame Guide

The handrail frame guide is a profile on which the handrail is fixed and guides it in a straight line in the direction of movement.

28. Handrail Entrance

 The handrail entrance is a part through which the handrail passes to enter and exit the internal space.

29. Handrail Inlet Guard

The handrail inlet guard is a part made of rubber fitted at the entry point of the handrail entrance through which the handrail passes.

30. Handrail Return Guide

The handrail return guide is a part made of hard plastic located before the handrail frame guide in the internal space. It guides the handrail into the handrail frame guide and vice versa.

31. Handrail Guide Roller 

The handrail guide roller is a roller that causes sliding as well as smoothing the movement of the handrail into the internal space.

32. Handrail Pressure Belt

The handrail pressure belt is a set of rollers located under the friction wheel and the handrail passes through them. The handrail pressure belt presses the handrail to the friction wheel and causes the turning of the handrail.

33. Handrail Tension Device

The handrail tension device is a set of rollers over which the handrail passes and can tighten or untighten it.

34. Balustrade Illumination

Balustrade illumination is an option which is positioned beneath the handrail and gives the escalator or moving walk balustrade a more stylish look.

35. Balustrade

The balustrade is a safeguard on both sides of the escalator which provides safety for the passengers as well as supporting the handrail. 

36. Upper Balustrade Decking

Specifically, in solid balustrades, we have upper decking, divided into inner & outer deckings, on which the handrail fame is installed.

37. Lower Balustrade Decking

Specifically, in the slim balustrade, we have lower decking, divided into inner & outer deckings.

38. Anti-Colliding Device

At the floor intersections or criss-cross escalator arrangement where there is a risk of passenger entrapment, an Anti-Colliding Device must be installed.

39. Anti-Sliding Device

 On the distance between two parallel escalators where there is a risk of passengers sliding, the anti-sliding device must be installed.

40. Access Restriction Device

In the spaces between two parallel escalators or when the escalator is installed beside a wall and the lower outer decking width is more than 125 millimeters, an access restriction device must be installed to prevent passengers from entering this restricted area.

41. Anti-Climbing

To ensure prevention of stepping on the lower outer decking and climbing from outside of the balustrade an anti-climbing device(s) must be installed.

42. Skirt Panel

The skirt panel is a vertical panel of the balustrade located on both sides of the steps with a specifically authorized distance from them on the entire route.

43. Skirt Brush

­The skirt brush is located on the skirt panel on both sides to prevent any objects from being trapped in the gap between the skirt and step.

44. Skirt Illumination

Skirt illumination can be installed on the skirt panel to create an attractive appearance. 

45. Direction Indicator

Direction indicator shows the direction of travel; especially in case the escalators are in standby mode.

46. Control Panel

Each escalator/moving walk has two control panels. The main control panel including the operating system is located at the upper machine room and the other one is located at the lower machine room.

47. Photoelectric Sensor

The Photoelectric Sensor has the task of detecting passenger entry into the escalator to change the escalator operational mode from standby to normal.

48. Drive Motor

The drive motor converts electrical energy into mechanical energy and creates the motive force.

49. Flywheel (Hand-Winding Device)

The flywheel is a disk installed above the motor to drive the motor manually in emergency cases. In some kinds of motor drives, the flywheel is designed with a heavy weight to provide a smoother start.

50. Gearbox

The gearbox is a device composed of gears and gear trains, used to give speed and torque conversions, from the drive motor to the main drive shaft by a chain.

51. Main Drive Shaft

The main drive shaft is the main mechanical movement system of an escalator or moving walk located in the drive station. It is composed of seven main parts including the main drive sprocket, drive wheel, main axis, main axis sprocket, turn table, bearings, and the support plate.

52. Handrail Drive Shaft

The handrail drive shaft is the handrail movement system located in the drive station. It is composed of four main parts including friction wheel, handrail drive axis, handrail drive axis sprocket, bearing unit.

53. Friction Wheel

The friction wheel is a large wheel that has a rubber edge located inside the handrail and causes its turning.

54. Brake Load

The Brake load equals the weight of the steps/pallets (considering the load of passengers standing on them), which the brake system must stop.

55. Emergency Stop Button

The red buttons are installed on both landings of the escalator to stop the device in times of emergencies.

56. Auxiliary Brake

Some escalators must be equipped with an additional brake based on their specification. The auxiliary brake stops the escalator in case the escalator speed exceeds the nominal speed or an unintentional reversal happens.

57. Main Drive Chain

The drive chain is a chain that transmits the motive force from the gearbox shaft to the escalator's main drive shaft. 

58. Handrail Drive Chain

The drive chain is a chain that transmits the motive force from the main drive shaft axis to the handrail drive shaft.

59. Step Chain

The step chain is composed of two sets of chains including rollers at regular intervals. These chains are linked together by several axels on which the escalator steps are mounted.

60. Newel Chain

The newel chain is a chain with several small bearings under the handrail that are located at the curved ends of the balustrade to cause a smoother movement of the handrail at newel ends.

61. Ceiling Opening Length

In order to install an escalator in a building, a ceiling opening must be considered on the upper floor with the appropriate length and width.

62. Wellway (Pit)

In order to install an escalator, a pit must be considered on the lower floor with an appropriate length, width, and depth.

63. Utilization

Escalators are divided into two categories of “Commercial” and “Infrastructure” based on their usage.

64. Installation Environment

Escalators are divided into three categories of “Indoor”, “Semi-outdoor” and “Fully-outdoor” based on their installation environment.

65. Safety System

The safety system is an arrangement of safety circuits and monitoring devices used to ensure the safety of escalator operation. 

66. Safety Devices

The safety devices are safety contacts and fail-safe circuits which perform safety functions in the escalator safety system.

67. Fail-Safe Circuit

The Fail-safe circuits are designed to define failure mode behavior in electrical and electronic systems.

68. Direction of Movement

 The direction where the escalator or moving walk is moving in.

69. Driving Station

 The point of the escalator or moving walk at the upper machine room where the steps start their movement.

70. Return Station

The point of the escalator or moving walk at the lower machine room where the steps are returning to be available for use.

71. Upper Landing

The point of the escalator or moving walk at the “Truss Upper Section” where the people enter or exit the escalator.

72. Lower Landing

The point of the escalator or moving walk at the “Truss Lower Section” where the people enter or exit the escalator.

73. Suspension Points

 The points in the ceiling of the installation area provided for lifting the escalator or moving walk.