Lift Systems: Learning Outcomes & Components PDF

Learning Outcomes Understand the various major components in lift installation. Understand the functions of the major components. Understand the safety functions in lift installation. Testing & Commissioning of lift Installation....

Learning Outcomes Understand the various major components in lift installation. Understand the functions of the major components. Understand the safety functions in lift installation. Testing & Commissioning of lift Installation. 1  Traction lift http://science.howstuffworks.com/elevator3.htm 2 Traction lift 3 Car Cage The car cage is essentially a cage made of fire resistant material supported on a structural frame that is connected to the hoisting ropes through the top member. hcs/Rev Jun04 4 How is the lift car kept stable during its vertical travel? By means of guide shoes that are fixed onto the side member of the structural frame of the car, the lift car is guided in its vertical travel sliding along the guide rails that are fastened to the both sides of the hoistway. 5 Lift Motor room Drive Sheave Brake Motor Gear Box Hoist rope Counter weight Lift Car 6 Lift System  Guide shoes & rail Lift Well Guide Rail Lift Car Guide Shoe 8 Traction machine 9 Electromagnetic Brake operates (i.e. closes) when electricity supply is cut off a fail-safe design. The brake assembly consists of 2 brake shoes lined with pads and is forced onto the brake drum by spiral springs. 10 Drive Sheave Pulley to which the lift machine transmits power to rotate it and hence move the hoist ropes to lift or lower the lift car. The drive sheave are made of steel and usually has at least 4 grooves to allow the hoistropes to sit in firmly. Due to the traction (resulting in friction) required between the sheave and the hoistropes, there could be significant wear and tear on the sheave. 11 Counterweight Function: Provide Traction balance the weight of the car plus a predetermined proportion (40% to 50%) of the maximum car load (contract load), thereby reducing the size of the motor. 40 80 80 Counterweight Cast-iron sections (weights) are often mounted in a steel framework. Hoistway ropes secured to counterweight top frame by screwed eyebolts, which allow rope adjustment. Four spring-loaded guide shoes are fitted to ensure that the counterweight will travel vertically and smoothly in its guides. 13 Car Travelling Cables Function: All electrical connections (power and signal) between the controller in the motor room and the car are made by means of a multi-core hanging flexible cable. hcs/Rev Jun04 14 Final Limit Switches 15 Compensating Ropes & Chains When the car is at the bottom of the well, the load on the motor is increased by the weight of the lifting ropes, which may be appreciable with high rises. Low speed lifts are sometimes fitted with compensating chains instead of ropes. 16 Buffers Spring Buffers – for slow speed lifts. Oil buffers – for higher speed lifts. 17 Hall call buttons, lanterns and floor indicators 18 Safety devices & operation Car Apron – car apron or toe guard is fitted to the bottom of a car lift at the entrance side and below the landing. The apron is provided to prevent a person’s foot from being trapped between the landing and the car during the levelling period. 19  Fireman lift Lift Well Fire Lift Normal lift For use by fireman Required if > 24 m Provided with Fire lift switch Top right corner of fire lift at designated floor Break Glass If switch activated -Fireman controls the lift Fireman -No interference from switch landing call points Designated floor: Floor suitable for direct evacuation, usually First floor 22  Lift Safety Operations EBOPS ARD Emergency genset Emergency Automatic Rescue Battery Operated Device >60 m buildings Power Supply Genset required Battery source in Located in Lift Lift motor room Upon power motor room failure, lift will For rescuing home at Lighting passengers by designated floor. Fan moving car to the Alarm bell nearest landing door and opening Minimum 4 hours the doors No need if building has Emergency Genset  Overspeed Governor http://science.howstuffworks.com/transport/engines-equipment/elevator5.htm 24 EBOPS Atleast 4 Emergency hours Lights Ventilation fan Emergency Battery Operated Power Alarm Bell Supply  ARD Bring the lift to the Open the nearest floor doors Automatic Rescue Device Not compulsory for Buildings with Emergency generator backup Lift Requirement for Handicaps 27  Lift requirement for Handicaps Minimum size of Grab bars at 1200 lift 1200mm W X height of 900 mm 1400mm deep 900 Symbols for Door opening handicapped lifts atleast 900 mm Landing call buttons between 900 to 900 to 1100 mm 1200 from floor Control panel buttons in car 900 to must be between 900 1100 900 to 1200 mm from floor 1400 Wheelchair stairlift or Platform lift Where it is impracticable to provide a lift or a ramp, a wheelchair stairlift or platform lift can be considered as a reasonable alternative for vertical circulation within the building compound. 29 Lift requirement for Handicaps If it is impracticable, Wheelchair stair lift Platform lift  Testing and Commissioning Lift contractor is responsible Test the various components of the lift Preventive Maintenance Inspect the safety related tests Regular maintenance is carried out Check for proper installation of signages Service report copy to be filed Record of repairs Monitor parts replaced Cleanliness  Statutory requirements Safety Officer – To be trained in rescue operation of lift Periodical Maintenance – Not > one month Examination - - Thorough testing every year -Safety equipment testing every year - No load test every year -Load test every 5 years - If defective, lift must be made inoperative Records of notices, certificate of inspection must be maintained Summary 1 Main Components Car cage – guide rail, guide shoe Motor room equipment – controller, traction machine, overspeed governor Brake, fail safe design Hoistway equipments counterweight, guide rail, wire ropes, travelling cable, limit switches compensating ropes and diverting pulley Pit equipments Buffer – Spring (< 1 m/s), Oil (> 1 m/s) Governor tension frame Landing equipments Push button, Floor indicators Safety Devices and Operation Terminal limit switches Final limit switches Buffers Safety gear Car apron Counterweight guard Hoistway gap 33 Summary 2 EBOPS Emergency Battery Operated Power Supply Atleast 4 hours operation Battery to supply power for Lighting Ventilation fan Alarm bell ARD Automatic Rescue device For rescuing passengers trapped in lift By moving car to the nearest landing door and open the lift doors Not required if building has emergency generators Fire Lift Normal lift For use of Firemen during emergency > 24 m Fire lift switch @ desginated floor Once operated - Fireman can control the lift - No interference from landing call points 34 Summary 3 Lift requirements for Handicaps Lift 1200 W X 1400 deep Door atleast 900 mm clear Landing call buttons 900 to 1100 mm from floor Control panel 900 to 1200 mm from floor Grab bars at 900 mm Symbols identifying the lifts If not possible Wheel chair stair lift Platform lift Testing and Commissioning Operational test Safety devices - buffer - limit switches - overspeed governor 35 Summary 4 Preventive Maintenance of Lift As per schedule Service Inspection report by a competent person Record of repairs Monitor parts replacement Cleanliness after repair Statutory requirements Safety Officer – trained in rescue, Fire lift, Escape route Periodical maintenance atleast once a month Periodical Examination 12 months – Thorough examination 12 months – test without load 5 years – test with full rated load 36