VF-W series

1 HEADQUARTERSB onfiglioli Riduttori Giovanni XXIII, 7/A40012 Lippo di Calderara di RenoBologna (Italy)tel: +39 051 647 3111fax: +39 051 647 have a relentless commitment to excellence, innovation and sustainability. Our team creates, distributes and services world-class power transmission and drive solutions to keep the world in seriesWormgears1 SUMMARYC hapterPageDescription1 GENERAL and units of to the ATEX Explosive European harmonised ATEX Levels of protection for the various categories of Definition of groups (EN 1127-1) Declaration of , installation and the type of Selection Selecting a gear unit with IEC motor Selecting a speed reducer with solid input Post-selection Operating conditions for ATEX-specified Service factor92 WORM GEAR UNITS FOR POTENTIALLY EXPLOSIVE of ATEX-specified and mounting VF W overhung Radial Thrust rating Motors not to IEC of Plug-in output VF-interchangeable foot kits KA, s Manufacturing instructions40 RevisionsRefer to page 42 for the catalogue revision index.

2 Visit to search for catalogues with up-to-date GENERAL SYMBOLS AND UNITS OF MEASUREAn[N]Theadmissible thrust loadrepresents the force which can be applied axiallyto the gear unit s shaft, along with the rated radial factoris a coefficient representing the severity of the duty for theoperating factortakes into account the influence of the ambienttemperature in calculating the computational torque. This factor is relevant forworm gear ratiois expressed as the relationship of the input shaft speed to theoutput shaft defined as follows:Jc[Kgm2]Moment of inertia of the driven [Kgm2]Moment of inertia of the [Kgm2]Moment of inertia of the gear loadacceleration factoris used to calculate the service factor, and isdefined as follows:KR-Thetransmission factoris a computational parameter, proportional to thetension generated by an external transmission keyed to the gear unit [Nm]Netoutput torqueMn2[Nm]Therated torqueat the output catalogue value is calculated for a service factor fS= [Nm]The application srequired should always be less than or equal to the gear unit s rated torque [Nm] Computational torque.

3 This is a virtual parameter used to select the gear unit,by means of the equation:n[min-1]Shaft [kW]Rated powerat the input shaft, calculated for a service factor fS= [N]Theadmissible radial loadshould always be more than or equal to thecomputational radial load. The point value is given in the catalogue for eachunit s gear frame size and transmission ratio, and refers to the shaft s factoris defined as follows:ta[ C] Ambient [min]Theoperating timeis the total duration of the work cycle [min]Therest timeis the interval of no work between two starts per hour. d-Thedynamic efficiencyis expressed as the ratio between the powermeasured at the output shaft and that applied to the input shaft:[]1 This value refers to the input shaft.[]2 This value refers to the output cause slight injury to [kW]The application srequired [N]Thecomputational radial loadis generated by an external transmission and,for the input and output shafts respectively, can be calculated from the INTRODUCTION TO THE ATEX EXPLOSIVE ATMOSPHEREU nder the provisions of Directive 2014/34/EU, an explosive atmosphere is defined as a mixture:a.

4 Of flammable substances, in the form of gases, vapours, mists or dusts;b. withair;c. under atmospheric conditions;d. in which, after ignition, the combustion spreads to the entire unburned mixture (it has to be noted that sometimes, mainly with dust, not always the whole quantity of the combustible material is consumed by the combustion).An atmosphere which may potentially be transformed into an explosive atmosphere due to operatingand/or ambient conditions is defined as apotentially explosive atmosphere. The products governedby Directive 2014/34/EUare intended for use only in a potentially explosive atmosphere defined inthis EUROPEAN HARMONISED ATEX STANDARDSD irective ATEX 2014/34/EUstipulates the minimum safety requirements for products intended foruse in explosion risk areas within the member countries of the European Union.

5 The directive alsoassigns such equipment tocategories, which are defined by the directive itself. The following table describes thezonesinto which the user of a plant, in which an explosiveatmosphere may occur, is required to divide the equipment application continuously or for long periodsPermanent121 Likely to occur in normal operation occasionallyPotential222 Not likely to occur in normal operation but if it does occurwill persist for short period onlyMinimalZonesFormation frequency of a potentiallyexplosive atmosphereType ofdangerGaseousatmosphereGDustyatmospher eDBONFIGLIOLI RIDUTTORI gear units selectedin this catalogue are suitable for installation inzones 1, 21, 2 and22, as highlightedin grey in the above from 20 april 2016the ATEX directives2014/34/EU come into force throughout the entire EuropeanUnion, and replace existing conflicting national and European laws on explosive atmospheres and theprevious directives 94/9/EC.

6 It should be emphasised that, for the first time, the directives also governmechanical, hydraulic and pneumatic equipment, and not only electrical equipment as has been the caseso regard to the Machinery Directive 2006/42/ECit should be noted that directive 2014/34/EUis a setof extremely specific requirements dedicated to the dangers deriving from potentially explosiveatmospheres, whereas the Machinery Directive contains only very general explosion safetyrequirements (Annex I).Consequently, as regards protection against explosion in potentially explosive atmospheres, Directive2014/34/EUtakes precedence over the Machinery Directive. The requirements of theMachinery Directive apply to all other risks regarding LEVELS OF PROTECTION FOR THE VARIOUS CATEGORIES OF EQUIPMENTThe various categories of equipment must be able to operate in conformity with the Manufacturer soperational specifications, at certain defined levels of independent means of protection orsafety capable of operating even when twoindependent faults occurThe equipment remains powered andoperational even in the presence of anexplosive atmosphereVeryhigh1 Two independent means of protection orsafety capable of operating even when twoindependent faults occurThe equipment remains powered andoperational in zones 0, 1, 2 (G) and/or zones20, 21, 22 (D)

7 HighM2 Protection suitable for normal operation andheavy duty conditionsPower to the equipment is shut off in thepresence of a potentially explosiveatmosphereHigh2 Protection suitable for normal operation andfrequent faults or equipment in whichmalfunction is equipment remains powered andoperational in zones 1, 2 (G) and/or zones 21,22 (D)Normal3 Protection suitable for normal operationThe equipment remains powered andoperational in zones 2 (G) and/or 22 (D)ProtectionlevelCategoryType of protectionOperating DEFINITION OF GROUPS (EN 1127-1)Group IApplies to equipment intended for use underground in parts of mines and those partsof surface installations of such mines, liable to be endangered by firedamp and/or IIApplies to equipment intended for use in other places liable to be endangered byexplosive RIDUTTORI products may not therefore be installed in mines, classified inGroup IandinGroup II, category summarise, the classification of equipment into groups, categories and zones is illustrated in thetable below, whereby the availability of BONFIGLIOLI RIDUTTORI products is highlighted in (1)GDGDGDZone020121222 Type ofprotectiongearunitc, kc, kc, kc, kType of protectionmotord, eIP6X + (A)IP5X o IP6X + temp.

8 MaxGroupImines,firedampIIotherpotentiall y explosive areas (gas, dust)(1)G= gasD= dustThis cataloguedescribesBONFIGLIOLIRIDUTTORI gearunits, intended for use in potentiallyexplosiveatmospheres, with limitation to categories 2 and products describedherein conform to the minimum safety requirements of European Directive94/9/EC, which ispart of the directives known as ATEX (ATmosph resEXplosibles).23 GDGD121222c,kc,kc,kc,kd,eIP6X+ (A)IP5 XoIP6X+ (gas,dust) DECLARATION OF CONFORMITYThe Declaration of Conformity, is the document which attests to the conformity of the product toDirective 2014/34/EU. The validity of the Declaration is bound to observance of the instructions givenin the User, Installation and Service Manual for safe use of the product throughout its service can be downloaded from where the manual is available in PDF format in anumber of instructions regarding ambient conditions are of particular importance inasmuch as failure toobserve them during operation of the product renders the certificate null and case of doubt regarding the validity of the certificate of conformity, contact the BONFIGLIOLIRIDUTTORI technical USE, INSTALLATION AND MAINTENANCEThe instructions for safe storage, handling and use of the product are given in the unit s User,Installation and Service can be downloaded the manual is available in PDFformat in a number of document must be kept in a suitable place.

9 In the vicinity of the installed gear unit, as areference for all persons authorised to work with or on the product throughout its service Manufacturer reserves the right to modify, supplement or improve the Manual, in the interests ofthe SELECTING THE TYPE OF SELECTION PROCEDURE:Determine the application service factor fSin relation to the type of load (K factor), number of starts perhour Zrand hours of operation per determine the power required at the motor shaft:The efficiency value d can be determined as follows (approximately):Worm gear unit efficiency - n1=1400 The selection procedure now depends on the type of gear unit, as follows:a. gear unit equipped with IEC motor fittingb. gear unit equipped with solid input as SELECTING A GEAR UNIT WITH IEC MOTOR FITTINGa. Determine service factorfsas formerly with reference to the rating charts, identify the gear unit which, for the required speed n2, provides a rated power Pn1such that:c.

10 Select an electric motor rated:d. Finally, check that the motor/gear unit combination generates a safety factor equal to or greater than the service factor for the application in question, in other A SPEED REDUCER WITH SOLID INPUT SHAFT- Calculate the value of the computational torque:ftp= 1 Type of loadAmbient temperature [ C]20 30 40 K1uniform shock shock gear units C, A, F, SWorm gear units VF, W- for the speed n2closest to that required, select the gear unit with a rated torque Mn2equal to orgreater than the computational torque Mc2, in other CHECKSOnce the gear unit or the gear unit with IEC motor fittinghas been selected, we recommend checkin the selection as follows: zMomentary peak torqueThe momentary peak torque is of the order of 200% of the rated torque Mn2. Check that thepoint value of the peak torque satisfies this condition and equip the installation with a torquelimiter if loadThe catalogue gives the values of the maximum admissible radial load for both the input shaft Rn1 and the output shaft Rn2.