ENGINEERING CLASS SPROCKETS - Precision Roller …

1 216 ENGINEERING CLASSSPROCKETSSPROCKETSPECIFICATIONSSPRO CKET TABLESThe sprocket Tables in this cat-alog have been designed foreasy reading. Listed is a partialinterchange, numbers of teeth,type construction, pitch diame-ters and maximum bores. Stan-dard Hub Data for both Solidand Splits are found withintheir corresponding type or types listed as available for a sprocket of aAny type other than listed types in sprocket Tables thatparticular number of teeth in the sprocket meet the limitations of size and/or work six types are listed:Consult B/W ENGINEERING Service If Spoked Arm isSprocket TypePlate CenterHunting Toothlisted in sprocket Data Table, Plate Center can beSpoked ArmSegmental Rimfurnished at additional SaverWide FlangeSplit ConstructionNot StandardAll split sprocketsType listed as available for a sprocket of a particularAny type other than listed in sprocket Table for a partic-number of teeth in the sprocket Tables.

2 One of theseular sprocket of a specific number of Typefour types:ABCC OffsetKeyseatingStandard keyway as specified in table Standard1) Extra KeyseatKeyways and Setscrews (page 219)2) Keyseating in definite location3) Keyseating in line or in pairsSetscrewsOne pair furnishedMore than one pairUp to and including the standard bore sizes that are1) Oversize boresBoringlisted in the sprocket tables. Tolerances are maintained2) Core-to-boreas per the Table of Standard Bore Facing HubsOne side if keywayedMachine facing hubs to exact dimensionsBoth sides if plain LengthsLength as listed in sprocket Hub Tables1) Longer than standard length will be provided atadditional Pin HubsNot StandardAll shear pin hubsBronze BushingsNot StandardAll bronze bushingsAllied-Locke Industries.

3 Reach for the star of 12/17/2001 09:54 AM Page 216217 ENGINEERING CLASSSPROCKETSSPROCKETFEATURESPLATE CENTERSPROCKETSS prockets are furnished in twobasic types .. Plate centerand Spoked Arm. Plate centersare generally used on smallersprockets whose size prohibitsthe use of spoked arms and ondrives and conveyors which aresubjected to frequent shockloads. They are also used whenthe maximum allowable chainpull is greater than that whichSpoked Arm SPROCKETS can ARMSPROCKETSS poked arms are found onlarge diameter SPROCKETS . Theyare used to reduce weight andfacilitate SAVERSPROCKETSC hain Saver SPROCKETS giveadded life to chain because ofthe special flange constructionon the rim. The chain side barsrest on the flange as chainwraps around the sprocket ,keeping the chain on the truepitch line and distributing wearover a greater contact Industries.

4 Chain - SPROCKETS - 12/17/2001 09:54 AM Page 217218 ENGINEERING CLASSSPROCKETSSPROCKETFEATURESHUNTING TOOTHSPROCKETSH unting Tooth SPROCKETS lastlonger than ordinary sprocketsand operate on this principle:Hunting Tooth SPROCKETS havean odd number of teeth and arehalf the pitch of the , every time the sprocketmakes a revolution, the chainlinks engage a new set of teeth,forward of the previously en-gaged set. Each tooth makescontact with the chain only halfas many times as it would on aregular sprocket , thus doublingthe life of the RIMSPROCKETSS egmental Rim SPROCKETS aredesigned to eliminate costlyshut down time during installa-tion and adjustment. They con-sist of a removable segmentedrim and a solid or split bodywhich are bolted obtain extra wear from thistype sprocket , after consider-able use, the rim sections maybe simply reversed, so that thechain makes contact with theopposite sides of the or entire SPROCKETS maybe replaced without removingshaft or bearings, making thistype of sprocket very desirableeconomically because of thesavings in labor and TOOTHCHAIN SAVERSPROCKETSThis type of sprocket combinesthe special features of the twopreceding types, providing ad-ditional life to both the chainand the FLANGESPROCKETST hese SPROCKETS are used inmany industries such as thelumber and paper industries assprockets for the delivery endof conveyors.

5 The wide flangeor side extension acts as aguard and helps keep materialfrom being wasted as it comesoff the end of the Industries .. the company that 12/17/2001 09:55 AM Page 218219 ENGINEERING CLASSSPROCKETSSPROCKETFEATURESSPLIT CONSTRUCTIONBoth Spoked Arm and Plate Center SPROCKETS areavailable with split construction. Split construc-tion is often specified for installations when it isdesirable or advantageous to mount or removethe sprocket from the shaft without disturbing ei-ther the shaft or the bearings. The method nowused in mounting a split wheel to the shaft givesincreased effectiveness in wheels are cast in one piece, machined, andsplit so that when bolted together the sprocketforms a solid construction. Split wheels are fur-nished with hubs on one side, hubs offset, or Chubs.

6 Rim lugs are employed when the diameterof the wheel makes them necessary. Since wheelsare cast in one piece and then split, it is neces-sary to give bore size required if ordered in core-to-bore special TYPESS prockets are supplied in various hub types ..each one designed for a specific need. The follow-ing defines and illustrates each of the basic A When a sprocket is described as type A, this in-dicates that there really is no hub which is part ofthe sprocket wheel. The wheel must be mountedon a flange or hub or other holding B This indicates that the sprocket has a hub extend-ing on one side only from the wheel. This type ofhub is generally found on small and intermediatesize C These hubs are centrally located, extending anequal distance on both sides of the wheel.

7 Thistype of hub is the most common type and is gen-erally found on large diameter C OFFSETType C Offset hubs are the same as type C mentioned above, but are slightly off , KEYS ANDSETSCREWSA single keyseat and one pair of set-screws arefurnished as standard on all SPROCKETS unless oth-erwise specified. Keys are not furnished as stan-dard and must be ordered. When keyway andsetscrew sizes are not specified, they are suppliedin accordance with the table of dimensionsheaded STANDARD KEYWAYS AND SET-SCREWS. Standard tolerances for straight andtapered keyways are: width . , depth . Setscrews are placed over key at 90 to the key unless otherwise specified. Taperedkeyways are supplied only when specified. Non-standard keyway sizes are KEYWAYS AND SETSCREWSD iameterDiameterKeyseatof setof ShaftWidthDepthscrew1 2-9 161 81 161 45 8-7 83 163 321 415 16-7 81 41 85 1615 16-13 85 165 325 1617 16-13 43 83 163 8113 16-21 41 21 41 225 16-23 45 85 165 8213 16-31 43 43 83 435 16-33 47 87 163 4313 16-41 211 23 449 16-51 211 45 83 459 16-61 211 23 4169 16-71 213 47 8179 16-815 1623 419-1015 1621 27 81 Allied-Locke Industries.

8 Reach for the star of 12/17/2001 09:55 AM Page 219220 ENGINEERING CLASSSPROCKETSSPROCKETFEATURESPHYSICAL PROPERTIESWe produce a special chemistry of gray iron thatenhances the ability of the iron to form a hard chilled layer on the rim of the sprocket . Allsprockets are a typical CLASS 30 gray iron. This ap-plies to all areas of the sprocket that are notchilled such as the hub and web sprocket wear surfaces have a minimumbrinell hardness of 400 in the rim areas which in-cludes the entire tooth profile. This chilled hard-ness depth ranges from 3 16 -1 2 . This comparesto a typical brinell hardness of 200 in unchilled unique method of manufacture allows us toproduce a sprocket with high hardness in thetooth area for long wear life while retaining a rela-tively soft and machineable hub BoringSprockets are bored to the sizes listed in the sprocket Data Tables.

9 Ourfactory holds all bores to the standard tolerances listed below. Boreslarger than listed can always be for boring SPROCKETS :1 Diameter and underNominal plus .001 Over 1 to 2 Nominal plus .002 Over 2 to 3 Nominal plus .003 Over 3 to 4 Nominal plus .004 4 and overNominal plus .005 PLAIN BORES prockets are supplied with plain bores when keyways and setscrewsare not to be furnished. SPROCKETS with plain bores should always bespecified when ordering. When only bore is given, SPROCKETS are auto-matically keywayed and set screws are ordering SPROCKETS not standard stock, it is always desirable tospecify what SPROCKETS will be bored to, so that proper size hub andcores can be FACING HUBSHubs will be faced to exact dimensions upon request, and at an addi-tional charge.

10 This refers to exact length of bore. SPROCKETS are nor-mally furnished faced one side only. Set screws are placed on the unfin-ished side of the hub since the unfinished side operates on the openside of the THAN STANDARD HUBSS tandard hub lengths are those specified in the Hub Data Tables. Iflonger hubs are required, they are available at additional PIN HUBSS hear Pin Hubs are used as a safety device to protect machinery fromoverload. The shear pin hub is keyed to the shaft and connected to theloose wheel by a pin which will transmit only the normal power require-ments plus a predetermined overload without shearing. The selection ofa shear pin rated at slightly more than twice the torque requirements isusually the proper size to use.