19SAFETYINTHEUSEOFABRASIVEWHEELSThisguidebookispreparedbytheOccupationalSafetyandHealthBranchLabourDepartmentThiseditionApril2008ThisguidebookisissuedfreeofchargeandcanbeobtainedfromtheofficesoftheOccupationalSafetyandHealthBranchoftheLabourDepartment.ItcanalsobedownloadedfromwebsiteoftheLabourDepartmentathttp://www.labour.gov.hk/eng/public/content2_8d.htm.Forenquiriesaboutaddressesandtelephonenumbersoftheoffices,pleasevisitthewebsiteoftheDepartmentathttp://www.labour.gov.hk/eng/tele/osh.htmorcall25592297.Thisguidebookmaybefreelyreproducedexceptforadvertising,endorsementorcommercialpurposes.Pleaseacknowledgethesourceas“SafetyintheUseofAbrasiveWheels”publishedbytheLabourDepartment.1SAFETYINTHEUSEOFABRASIVEWHEELSSAFETYINTHEUSEOFABRASIVEWHEELS2SAFETYINTHEUSEOFABRASIVEWHEELSCONTENTSPageINTRODUCTION............................................................................3SELECTIONOFWHEELS.................................................................3OPERATINGSPEED........................................................................4MARKINGSYSTEMFORABRASIVEWHEELS.................................5MOUNTING...................................................................................5MOUNTINGOFDEPRESSED-CENTREWHEELS..............................6GUARDS........................................................................................7WORK-RESTS..................................................................................7PROTECTIONOFEYES..................................................................7TRUINGANDDRESSING...............................................................8SAFETYANDTHEOPERATOR........................................................8ENQUIRIESANDCOMPLAINTS.....................................................9SKETCHESANDTABLES/FORMS...............................................103SAFETYINTHEUSEOFABRASIVEWHEELSIntroductionAbrasivewheelsareextensivelyusedinindustriesforvariouspurposes.Theuseofabrasivewheelsinanunsafewayoftencausesaccidentsleadingtopersonalinjuriesand/ordamagetoproperties.Themaindangersare—(1)burstingofwheelsastheresultof:(i)defectivewheel(ii)overspeeding(iii)faultymounting(iv)misuse(2)contactwiththewheel;and(3)injurytotheeyesfromflyingparticles.Thepurposeofthisguidebookistoadvisereadersontheprecautionsforthepreventionofaccidentsintheuseofabrasivewheels.Itdoesnotincludetechnicalaspectsofgrindingoroperationaltechniques.SelectionofWheels*Consultthemanufacturerforthepropertypeofwheelstosuitaparticularjob.Generally,softwheelsaremoresuitableforhardmaterialsandhardwheelsforsoftmaterials.*Donotusedefectivewheels.Checkforsoundnessofwheelsbya‘ringtest’.(SuspendthewheelverticallyandtaptheareasasshowninFig.1withalightnon-metallictool,suchasawoodenscrewdriverhandle.Itshouldring.Donotusethewheelifitsoundscracked.)*Wheelsshouldbekeptdryandnotexposedtoextremetemperatures.Ifnotinuse,theyshouldbestoredproperlyinsuitableracksasinFig.2.4SAFETYINTHEUSEOFABRASIVEWHEELSOperatingSpeed*Checkthatthespindlespeedofamachinedoesnotexceedthemaximumpermissiblespeedofthewheelasspecifiedbythemanufacturer.Thespindlespeedandthemaximumpermissiblespeedofthewheelshouldbemarkedinrevolutionsperminute(rpm).Butincasethewheelismarkedtogivetheperipheralspeedinfeetperminute(ft/min)orinmetrespersecond(m/sec),thefollowingformulacanbeusedforconversionintorpm:∆...
