Materials and Construction of Elevator Ropes and Belts, Exams of Forensics

Download Materials and Construction of Elevator Ropes and Belts and more Exams Forensics in PDF only on Docsity! Elevator 245-250 Exam 93 Questions with Verified Solutions for 2024. What is meant by suspension regarding elevator equipment? - ANS A means of connecting the cars and counterweights with the hoisting machines. What are the means of suspension that are used in the elevator industry? . - ANS Ropes or belts are the most common materials used for suspension What materials are used in the construction of governor ropes and car ropes? - ANS Iron, monel, bronze, fiber or steel What is meant by the term lang lay? - ANS When the wires of the strand form an angle with the axis of the rope What is meant by rope lay? - ANS The direction that the strands are coiled around the core material What is the most common finish on ropes? - ANS Bright or uncoated What are the components of a wire rope? - ANS Wires, that form the strand, Strands that lay around the core, and core material What materials is used in the construction of belts for suspension? - ANS Stranded aramid fiber, carbon fiber and non-circular elastomeric coated steel belts NECSBS What is the core of a rope made from? - ANS Either fiber or wire When would iron grade steel be most likely be used? - ANS When working on older equipment How many different types of steel are used in the construction of ropes? - ANS 6 different types of steels can be used Traction Steel (TS); Plow Steel (PS), mild plow steel (MPS)Improved plow steel (IPS, Extra Improved Plow Steel (EIPS) Extra Extra Improved Plow Steel (EEIPS) What is special about Warrington ropes? - ANS The inside wires of the strands are the same diameter. While the wire that make up the outer strand edge alternate between the sizes used What are the benefits of using lang lay ropes? - ANS They have a greater resistance to abrasions and greater flexibility that regular ropes What is significant about Seale ropes? - ANS The strand is made up of 1 large wire surrounded by 9 small wires which are surrounded by 9 large wires What are disadvantages of using lang lay ropes? - ANS Harder to handle; more likely to untwist, kink easier and easier to crushing What is a drawback to using Warrington ropes? - ANS They aren't wearing resistant What do 6 x 19 regarding ropes mean? - ANS The first number represents the number of strands that make up the rope. The second number is the number of wires per strand What is a benefit of using preformed ropes? - ANS Broken wires are less appt to stick out from the surface What are preformed ropes? - ANS Ropes that have the strands formed to helical shape during manufacturing process to make the final product. When should a tiller rope be used? - ANS To manually change the direction in old controllers. What is meant by pre stretched ropes? - ANS That the ropes are stretched during the manufacturing process Why are ropes pre stretched? - ANS To reduce the amount of construction, stretch (Stretching that occurs after the ropes are installed When should tiller ropes be used for hoisting? - ANS Never What must be installed on shackles after they are finally in place? - ANS An anti-rotation device How much of the dead end of the rope should be left after feeding the rope into the shackle? - ANS At least 6-9 inches above the socket Who many retaining clips should be installed above the shackle after the rope is installed? - ANS At least 2 the 1st should be placed 4 times the diameter of the rope the 2nd 8 times the diameter of the rope What is the rate of construction stretch for pre-stretched ropes? 50% less than none pre-stretched ropes - ANS Which end of a wedge shackle should the live end of a rope be placed? - ANS Towards the rod end of the shackle What should all shackles have on the rod end of the shackle? - ANS Be double nutted and have a cotter key for each shackle What is elastic stretch? - ANS When a rope stretches due to the load placed on the ropes; once the load is removed the rope returns to the original size What is the benefit to ordering pre-stretched rope for roping operations? - ANS Pre- stretched rope has significantly less construction stretch How much rope should be at the dead end past the end of the socket? - ANS At least 6- 9 inches if using belts ensure that it is a manageable size What should be used in a situation when babbitt or wedge clamps can't be used? - ANS Thermosetting resin sockets What must be done to ensure safety when using old ropes to pull new ropes during re- roping? - ANS Because of the increased hazard safety is paramount so holdback or separating devices must be used What is the only method authorized when using belts to re-rope a car? - ANS The wedge clamps Once the new ropes reach the counterweight frame what should be done? - ANS The married sections of the old rope must be separated from the new rope What tools are used to cut ropes/ belts? - ANS Bolt cutters or hydraulic cutters What is the 3rd purpose of lubricating ropes? - ANS To guard against corrosion What is the best method for applying lubrication to ropes? - ANS By a felt pad wick type lubricator What is an indicator that belts need to be replaced? - ANS If the elastomeric coating is so worn that the steel cord is exposed During the inspection of elevator in service a damaged rope is discovered what must be done? - ANS All the ropes must be replaced Where do most codes require rope data to be shown? - ANS The Crosshead of the elevator What should be done before starting any roping operation at the designated landing? - ANS The building needs to be protected so place Masonite/ plywood around the door frame, and building floors What are key factors that should be explained to customers before starting any roping operations? - ANS The amount of space needed for storage: the amount of space needed around the openings where the work will be performed Where are the shackles attached on a 2:1 roping? - ANS To a dead-end hitch plate that are secured at the top of the hoist way Where are the shackles attached on a 1:1 roping? - ANS To the counterweight frame and to the crosshead on the car top What must be done if you anticipate using any type of welding during roping operations? - ANS A fire permit may be required; fire extinguishers and fire watch; and protect systems from heat and smoke During the inspection of elevator that has not yet been turned over to the customer a damaged rope is discovered what must be done? - ANS Only the damaged rope must be replaced Which ropes are more likely to have internal failures? - ANS Governor/ compensating ropes due to the lighter loads and the smaller drive sheaves According to code what is required on governors? - ANS The governor rope tag must be attached to the governor rope fastening What is the 2nd purpose of lubricating ropes? - ANS To prevent friction and locking between the wires and strands within the rope What is 1st purpose of lubricating ropes? - ANS To protect the rope core from deteriorating Where should the car be located to inspect a traction machine with 1:1 roping? - ANS At the top of the hoist way to allow the ropes to be examined from the car top on the counterweight side Where do need to be to inspect a drum machine? - ANS In the overhead machine space How far should the car be moved between each stop when you're inspecting the ropes? - ANS 2-3 feet and examine each rope at each stop What should be done to inspect an excessively dirt or overlubricated ropes? - ANS The rope must be cleaned/ remove the excess lubrication Where are the shackles attached on 2:1 roping? - ANS To dead end hitch plates at the top of the hoist way What is the measurement of a lay on a rope? - ANS 6 ½ times the diameter of the rope When is it possible to replace only one set of ropes when damage is detected? - ANS If the damage was detected prior to the elevator being placed in service. Otherwise, if damage is detected the entire set must be replaced What are crown breaks? - ANS The number of broke wires per lay (the length of a rope which on spiral completes 1 turn) What does the term rouging mean with regards to roping? - ANS A lack of lubrication between rope components (individual wires, strands, hemp) What can be an indication of damage on a preformed rope? - ANS Breaks in the valleys of the rope Can rouging be corrected by field lubrication? - ANS No How do you test the diameter of a rope? - ANS With a rope diameter gauge Where are the shackles attached on 1:1 roping? - ANS To the crosshead on the cartop and the counterweight frame