Millwright Level 2 Chain Drives 2025-2026 Guide, Exams of Mechanics

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Millwright Level 2 Chain Drives 2025 - 2026 Guide

Name four types of chain links - ANSWER-Roller Pin Connecting Offset links have two bushings that are press fit into two roller link plates and links have two rollers that spin freely on the bushings - ANSWER-Roller A connecting link has what parts? - ANS WER2 pins press fitted and riveted permanently to a link plate A link plate that can be press or slip fit on the pins Securing device (spring clip, cotter pin, spring pin, cle) Another name for roller link plates - ANSWER Side plates _ links are oversized and have lubricated bushings - ANSWEFR-Rollerless _ links have two link plates which hold the pins and roller links that pivot on the pins - ANSWERPin chain is an assombly of alucrnating roller links and pin links - ANSWER-Standard roller What is tho purpose of a connecting link? - ANSWEF_Joins a roller chain, making it endless What is a slip fit connector? - ANSWEF-Their side plates are secured by pins or clips. Used for efficient chain removal What are press fit connectors? - ANSWEF-Riveted for permanent connections and heavy applications. of clips face direction of travel - ANSWER-Head end and spring _ links are used when it's not possible to have a standard connecting link to have an even number of pitches - ANSWER-Oftset (aka half link) links lengthen chains one pitch at a ume - ANSWER-Onc-pitch offset links are designed for heavy applications. The pin is riveled making a permanent connection. - ANSWER-Two-pitch offset All Roller chain dimensions are related to the pitch in what way? - ANSWEI-They’re all fractional multiples of the pitch What is the pilch in roller chain? - ANSWEF_Distancc belween centres of adjacent joml members What is the chain width in roller chain?- ANSWER-The minimum distance be and it’s 5/8 of the pitch sen link plates What does the letter H signify in roller chain code?- ANSWER-Heavy series What does a hyphenated number following the chain number in roller chain code signify? - ANSWERNumber of strands (100-2 means double strand) A multiple strand chain has a power delivery rating than the number of strands 1) slightly less 2) equal 3) slightly more 4) oxponentially less - ANSWER Slightly less Why do multiple chain drives require accurate alignment? - ANSWER-Keep load evenly distributed over each strand drive chains have twice the pitch than standard chain and are used when speeds are low and have relatively light loads - ANSWEF-Donble pitch (aka extended pilch) _ chain has toothed link plates on pin connectors. They pass over the sprocket like s timing belt - ANSWER-Silent _ chain has no sliding action which creates a smooth and quiet operation. Used on high speed drives - ANSWER-Silen| Silent chain sprockets look like - ANSWER-Gcars Flanged, centre guide plate, side guide plate are examples of sprockets - ANSWER Silent chain What are the 4 sprocket types? - ANSWER-A, B, C, and D Type __ sprockets (aka plain or disk), are mounted on hubs by being bolted or welded to them 1B 2A 3)D 4) C- ANSWER-2) A Type ____ sprockets have a hub on both sides 1D 2A 3)B 4) C- ANSWER-4}C Type ___ sprockets have a hub on a single side DA 2)B 3)C 4)D- ANSWER-2}B Type sprockets are detachable and split in half along the centreline sprockets have odd number tooth count 1) single cut 2) double cut 3) hunting tooth A) standard cut - ANSWER-Hunting tooth sprockets are cut where every other tooth delivers power. 1) single cut 2) double cut 3) hunting tooth 4) standard cut - ANSWER-2) Double cut What is an advantage of even number of teeth on sprockets? - ANSWER-Wear is on every other tooth and can be rotated to provide “a new set of teeth" What is a disadvantage of sprockets with an odd number of teeth? - ANSWER-Wears on all teeth therefore cannot be rotated What is the efficiency of a roller chain drive? - ANSWER-98-99% Name 3 advantages of roller chain drive assemblies - ANS WERNo slippage on overloads or heavy loads Tako up devices not required for tension Shortened quickly Handle high temps Accommodates reversing drives Variety of pitches readily available What is the minimum arc of contact for chain drives? - ANSWER-120 degree wrap (or 1/3 of tooth engagement} What is used in a chain drive system that has too long of a distance between shaft centres? - ANSWER-Jackshaft (aka countershaft) A hardened sprocket is used on a chain drive operating ata speed and loaded drive 1) high speed and heavily 2) slow speed and lightly 3) high speed and lightly A) slow speed and heavily - ANSWER-4) slow speed and heavily Hardened sprockets are used on chain drives that have a operating speed and sprockets have or less 1) slow and 25 teeth 2) slow and 20 Locth 3) high and 23 teeth Aj high and 20 teeth - ANSWER-3) high and 25 teeth Rule of thumb for a driven sprocket ona chain drive is tooth count should not exceed - ANSWER-120 4) close to the larger sprocket - ANSWER3) close to the smaller sprocket. When would guide rails need to be installed on a chain drive? - ANSWER-At running speeds of $0m/min or less When aligning sprockets, they need to he - ANSWER Level to each other What is a feeler bar used for? - ANSWER-To align shafts For chain drive purposes, Piano wire, string, and laser beams are common tools to measure: - ANSWER-Long centre distances How many points of contact are needed when aligning sprockets? 2 4)6- ANSWER-2) 4 What should be checked on a sprocket before installation? - ANSWER-Runout After the first alignment reading of a sprocket set up, what should be done for a second reading to ensure accuracy? - ANSWER-Rotatc the drive 180 degrees How can sprockets be scl up with a shall that has endplay? 1) follow normal procedure 2) cannot be done. Must correct endplay issue 3) have one sprocket slightly off alignment 4) align sprockets in running position. - ANSWER-4) Align sprockets in running position Where should oil be applied on roller chains? - ANSWER-To the Outside and inside plate edges Tn what 3 ways are chains lubricated - ANSWER Manually Semi automatically Automatically How arc chains lubricated mannally and what is the Type 1 - ANSWER-Brush or oil can - Type A How are chains lubricated semi automatically and what is the Type letter? - ANSWEF-Drip cup - Type B How are chains lubricated automatically and what is the Type letter? - ANSWER-Oil baths and streams - Type C When a chain is running close to the tips of sprocket teeth, this indicates: - ANSWER-Chain slrotch What are 2 ways to check for chain stretch? - ANSWER-Push and pull method ( less accurate } Compare to anew chain is same length and size (more accurate) Worn parts Loose chain What can cause a stiffened chain? - ANSWEF-Incorrect lubrication Corrosion and rust What can cause broken chain or sprockels? - ANSWER-Shock Worn chain or sprocket Rust or corrosion * ifa chain starts Lo climb sprocket Ieoth afier 6 months, what could this indicate? 1) on backwards 2) rusted 3) incorrect pitch 4) stretched - ANSWER-4) stretched