ACME LEAD SCREWS I - SDP/SI
IACME LEAD SCREWSCENTERLESS GROUND AND STANDARD ROLLED PHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COM2G THREADFORM MATERIAL:RInch300 Series Stainless Steel01 FEATURES:Low cost alternative to ball screw assembliesIdeal in corrosive environmentsWell suited for vertical motion applicationsT1 SPECIFICATIONS:Lead accuracy: 0.010 inches per footStraightness: 0.010 inches per foot23456INCH COMPONENTCATALOG NUMBERAB11SAScrewSizeCodeLengthin FeetScrewSize 2*3708137084 37055 2.56.61.63.78.86.88Leadin.AvailableLengths71, 25.100.200.125.10091, 3, 611122, 4, 6131415*Left-hand threads available on special order. Fast lead high helix lead screws.REV: 03.27.17 KT109-216
IANTI-BACKLASH ACME NUTS MATERIAL:PHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMAcetal with PTFER TEMPERATURE RANGE:Inch32 F to 180 F01For use with Acme Lead ScrewAB11SA-.T12TH3O.D.4CL5INCH COMPONENTCatalog SN-37121ABAB22SN-37122ABAB22SN-37161ABCatalog ize1/4-161/4-20Numberof 589Max.StaticLoadlbfDragTorqueoz. in.225Use 01314Continued on the next page15 Copyright2018 Stock Drive Products / Sterling Instrument, a Designatronics company. All rights reserved.9-6D82016
IANTI-BACKLASH ACME NUTS MATERIAL:PHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMAcetal with PTFER TEMPERATURE RANGE:Inch32 F to 180 F01For use with Acme Lead ScrewAB11SA-.T12TH3O.D.4CL5INCH COMPONENTCatalog SN-10010ABCatalog mberof . in.100lbf5001507505-81608007-1030015004002000Use inued from the previous page1415 Copyright2018 Stock Drive Products / Sterling Instrument, a Designatronics company. All rights reserved.9-7D82016
ITHREAD MOUNT ACME NUTSPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COM MATERIAL:RBronze SAE 660Inch TEMPERATURE RANGE:0-65 F to 250 F1T SPECIFICATIONS:Friction Coefficient: .2 to .31Lubrication is recommendedFor use with Acme Lead ScrewAB11SA-.23TH45O.D.CL6INCH COMPONENTCatalog AB20BN-10008AB20BN-10010Catalog rof .5001-3/8-16Leadin.Torque toRaise 1 lb.oz. 501.0001.000789101.5001.50011Use -0751415REV: 03.27.17 KT9-916
ITHREAD MOUNT ACME NUTS MATERIAL:PHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMAcetal with PTFER TEMPERATURE RANGE:Inch32 F to 180 F01For use with Acme Lead ScrewAB11SA-.T12TH3O.D.4CL5INCH COMPONENTCatalog AB21SN-37161Catalog ticLoadUse f 505/8-1870350AB250F-0371314Continued on the next page15REV: 03.27.17 KT9-1016
ITHREAD MOUNT ACME NUTS MATERIAL:PHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMAcetal with PTFER TEMPERATURE RANGE:Inch32 F to 180 F01For use with Acme Lead ScrewAB11SA-.T12TH3O.D.4CL5INCH COMPONENTCatalog Catalog 4-101-81-10C.375.500Numberof 001.500910Use withFlange11AB250F-0501213AB250F-075Continued from the previous page1415REV: 03.27.17 KT9-1116
IFLANGE MOUNT ACME NUTS MATERIAL:PHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMTurcite X (Acetal, PTFE & Silicone Filled)R TEMPERATURE RANGE:Inch32 F to 160 F01 FEATURES:LightweightLow costLow frictionSelf-lubricatingUp to 75,000,000 inches of travelT1Left-hand threads available on special order2For use withAcme Lead ScrewAB11SA-.3Ø1.125 B.C.WITHIN .005 T.I.R.Ø.7104.705Ø .695.208Ø .1985.1875 R.3 PLACES6.065.0551.500 REF.71.75.195INCH COMPONENTvCatalog rewSizeNumberof c LoadlbfDynamicLoad**lbf125252505035070Torque toProduce1 lbfoz. .581.141.851.91.801.07* Nut has ribbed body shape within the .710 dimensions above.** Reduce load by 90% for continuous load applications.91011121314Turcite is a registered trademark of Trelleborg Sealing Solutions U.S., Inc.REV: 03.27.17 KT8159-1216
IFLANGE MOUNT ACME NUTS MATERIAL:PHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMAcetal with PTFER TEMPERATURE RANGE:Inch32 F to 180 F01For use with Acme Lead ScrewAB11SA-.ØB.C.1LFØDØE2ØA31/2, 5/8 AND 3/4 SCREWSØB.C.ØELFØDT4.469ØA53/8 AND 7/16 SCREWS6INCH COMPONENTCatalog Catalog 2.AB29FT-75.ScrewSizeNumberof 1.502.00EDia.lbf6075125789175275F.20.20Design Load.25.30B.C.Dia.1.1251.1881.438101112131415REV: 03.27.17 KT9-1316
IMOUNTING FLANGESFOR ACME NUTSPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMR MATERIAL:Aluminum 6062-T6Inch01T123ØC4EA56ØDBINCH COMPONENTCatalog REV: 03.28.17 KT9-1416
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRBall and Acme Screw Drive Mechanisms:This section will introduce most of the more common types of drive mechanisms found in linear motion machinery.Ideally, a drive system should not support any loads, with all the loads being handled by a bearing system. Topics discussedwill include, but not be limited to, the mechanism of actuation, efficiency, accuracy, load transfer, speed, pitch, life cycle,application, and maintenance. Each type of drive system will be accompanied by a diagram and useful equations whenapplicable. Some of the terms used with screws, the most common drive component, are as follows:lead – advance of the nut along the length of the screw per revolution.pitch – distance between corresponding points on adjacent thread forms (pitch lead / # of starts).# of threads – number of teeth found along a unit length of the screw (1 / pitch).# of starts – number of helical grooves cut into the length of the shaft.outer diameter – largest diameter over the threaded section (at top of threads).root diameter – smallest diameter over the threaded section (at base of threads).stub – specific type of ACME thread where the root diameter is larger to provide for a more heavy-duty screw(the threads look “stubby”).critical shaft speed – operating speed of spinning shaft that produces severe vibrations during operation.This is a function of length, diameter, and end supports.maximum compressive load – maximum load that can be axially applied to the screw before buckling or permanentdeformation is experienced. Also referred to as column strength.end bearing supports – the screw must be supported at one or both ends with thrust type bearings. Dependingupon the application, it may also be desirable to provide for a stiffer system by incorporating angularcontact bearings (fixed support).Although shafts, gear trains, belt and pulley, rack and pinion, and chain and sprocket drives are practical in otherapplications, they require special consideration when used in CNC machinery. This is because there is typically backlashassociated with these types of drives, which increases the system error. Thorough technical descriptions of these types ofdrives can be found in the SDP/SI Components Library, www.sdp-si.com.Lead NutLead Screw Lead Screw SystemLead screws are threaded rods that are fittedwith a nut. There are many types of threads used, butthe most prevalent in industry is the ACME lead screw.Because the ACME thread is an industry standardizedthread style, it is easily interchanged with parts fromvarious manufacturers. The basic function of a screwis to convert rotary input motion to linear outputmotion. The nut is constrained from rotating with thescrew, so as the screw is rotated the nut travels backand forth along the length of the shaft. The friction onthe nut is a function of environment, lubrication, load,and duty cycle; therefore, practical life cycle is difficultto quantify.Lead screw/nut drive systems are available in a variety of sizes and tolerances. Contact is primarily sliding,resulting in relatively low efficiency and a wear rate proportional to usage. Advantages include the self-locking capability inback drive mode. Diameter should be at least three times greater than the lead which is good for vertical applications, lowinitial costs, near silent operation, manufacturing ease, and a wide choice of a materials. Disadvantages of ACME screwsinclude lower efficiencies (typically 30-50%, depending on nut preload) which require larger motor drives, and unpredictableservice life. For increased efficiencies see Ball Screws; SDP/SI Series S6513HM.Ball screws are very similar to lead screws withthe exception of a ball bearing train riding between the screwand nut in a recirculating raceway. This raceway is generallylubricated, which allows for predictable service life. Due tothe increased number of mating and moving parts, matchingtolerances becomes more critical. The screw threads haverounded shapes to conform to the shape of the balls. Thefunction, terminology, and formulas are the same as found withlead screws, however the performance of ball screws is farsuperior. The rolling action of the balls versus the sliding actionof the ACME nut provides significant advantages. Advantagesof ball screw drives are increased efficiency (typically up to90 – 95%) which allows required motor torque to be lower,predictable service life, low wear rate and maintenance costs.Disadvantages include: limitedmaterial choice, higher initial?-?cost, and an auxiliary brake is required to prevent back drivingwith vertical applications.Ball NutT123456789101112 BallsBall Screw 1314Ball ReturnBall Screw System159-1516
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRT12Helpful Formulas:When determining the amount of input torque required to produce an amount of output linear force, there are manyfactors to consider. The following equations provide a practical approach in making force and torque calculations.Force Calculations:F T FA F E F Fwhere: F T Total ForceF A Acceleration ForceF E External ForceF F Friction Force3WaFA ––– ––– lb.g124where: W total weight to accelerate (lb.)a linear acceleration (in./sec2)g acceleration from gravity (ft./sec2)5678910(1)(2)External Force (FE) may be due to gravity in vertical applications, or may be from external work requirements(feeding material, stretching material, etc.)Friction Force (FF) required to overcome all of the friction in the load bearing system (with a low friction bearingsystem, this can be negligible)The Total Force must be below the compressive (thrust) rating of the screw chosen. A modest factor of safetyshould be added to the total force so that unexpected dynamic loads are safely handled by the screw system.Torque Calculations:LT FT –––2 πe(3)where: FT Total Force (lbs)L Lead (inches)e efficiency (no units, use 0.9 for Ball screws assemblies.)Total Force 100 lbsLead 0.20 inchesEfficiency 0.9 (Ball screw)(3)111213141516100 lbs 0.20 inchesT �– 3.54 lb.-inches2π(0.9)Total Force 25 lbsLead 0.10 inchesEfficiency 49%(3)25 lbs 0.10 inchesT �–– 0.81 lb.-inches2π(.49)The Torque required should be well below the torque rating of the motor chosen. A modest factor of safety should be addedto the torque required so that unexpected dynamic loads are safely handled by the driving system.9-16
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMSelecting and Sizing Screw Drive Systems:RWhen choosing a particular screw for a given application, there are several factors to be considered. Required rpm,critical speed and maximum compressive strength are the most important design features that determine screw designparameters, and can be calculated according to the following equations. Since thread style design is irrelevant in thesecalculations, the same equations and charts can be used for both lead screws and ball screws. Bearing configuration mustbe considered when using these equations. The following diagrams represent the typical bearing end support arrangements.T1A. Fixed-FreeB. Simple-SimpleC. Fixed-SimpleD. Fixed-Fixedlinear velocity (in./min.)rpm �–––lead (in./rev.)Maximum Speed:2(4)3Maximum Load:dC F (4.76 x 10 6) –––L2Swhere:CS critical speed (rpm)d root diameter of screw (inches)L length between supports (inches)F end support factor (see diagram)case A.: 0.36case B.: 1.00case C.: 1.47case D.: 2.23(5)d4P F (14.03 x 10 6) –––L2where:(6)P maximum load (lbs) (critical load)d root diameter of screw (inches)L maximum distance between nut and loadcarrying bearingF end support factor (see diagram)case A.: 0.25case B.: 1.00case C.: 2.00case D.: 4.00The formulas above can be represented graphically by the charts on following pages. These charts have beencompiled for screws made of stainless steel. Speeds, loads, diameters, bearing arrangements, and products are referenced.It must be realized that a screw may be able to rotate at very high rpm’s, but the nut may have more strict limitations. Forthis reason, we have truncated the ball screw rpm diagrams to a top end of 4000 rpm and provided each type screw withtheir own charts. Please note that the ball screw charts are only represented for screws of 16 mm and 25 mm diameters.456789101112131415?-?9-1716
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRTravel Rate vs. LengthFor Standard ACME Lead 60004Travel Rate in 3642INCHESBOTH ENDS SUPPORTEDREFB10203040506070INCHESONE END FIXEDOTHER END SUPPORTEDREFC12243648617385INCHESBOTH ENDS FIXEDREFD153045607590105INCHES12ONE END FIXEDOTHER END 42516110080Length9-18
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRCRITICAL SPEEDTPURPOSEThis graph was designed to simplify the selection of the proper lead screw so as to avoid lengths and speeds which willresult in vibration of the assembly (critical speed). The factors which can be controlled after a particular maximum lengthis determined are: method of bearing support and choice of lead screw diameter.1USE OF THE GRAPH21.2.3.4.5.Choose preferred bearing support means, based on design considerations.On the proper bearing support horizontal line (A, B, C or D) choose length of lead screw.Draw vertical line at the lead screw length, determined at (2.), and draw a horizontal line at the travel rate.All screw diameters to the right and above the intersection point in (3.) are suitable for this application.Screw sizes are coded as follows:34Diameter (in).5StartsThreads / in.6Maximum Length (in.) Adjusted for Bearing Support"Y" DimensionYXXAYBXYCXY7D89101112131415?-?9-1916
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRCompression Load vs. LengthFor Standard Ball Screws and ACME Lead sion Load lbs3000562000100080075101600740082009100300ONE END FIXEDOTHER END 015202530INCHES10BOTH ENDS SUPPORTEDREFB102030405060INCHES11ONE END FIXEDOTHER END SUPPORTEDREFC142842577185INCHESBOTH ENDS FIXEDREFD20406080100120INCHES12Length131415169-20
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRCOLUMN LOADSTPURPOSEThis graph was designed to simplify the selection of the proper lead screw so as to avoid buckling when subjected to theaxial loading by means of the nut. The factors which can be controlled after a particular maximum length is determined are:method of bearing support and choice of lead screw diameter.1USE OF THE GRAPH21.2.3.4.5.Choose preferred bearing support means, based on design considerations.On the proper bearing support horizontal line (A, B, C or D) choose length of lead screw.Draw vertical line at the lead screw length, determined at (2.), and draw a horizontal line at the compression loadthe unit is exerting on the screw.All screw diameters to the right and above the intersection point in (3.) are suitable for this application.Screw sizes are coded as follows:34Diameter (in.)5StartsThreads / in.6Maximum Length (in.) Adjusted for Bearing Support"X" DimensionYXXAYBXYCXY7D89101112131415?-?9-2116
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRCRITICAL SPEED & LOADLOAD AND SPEED LIMITS ON 16 mm BALL SCREWST1CRITICAL SPEED23SpeedrpmBEARING SUPPORT TYPES4FF – Fixed, FixedLength mm56FO – Fixed, OpenCRITICAL LOAD789FS – Fixed, SimpleLoadkg10SS – Simple, Simple1112Length mm131415169-22
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRCRITICAL SPEED & LOADLOAD AND SPEED LIMITS ON 25 mm BALL SCREWST1CRITICAL SPEED2Speedrpm3BEARING SUPPORT TYPES4FF – Fixed, FixedLength mm56FO – Fixed, OpenCRITICAL LOAD78FS – Fixed, SimpleLoadkg9SS – Simple, Simple101112Length mm131415?-?9-2316
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRBALL & ACME LEAD SCREW ASSEMBLYLIFE EXPECTANCYT16 mm LIFE EXPECTANCYSPECIFICATIONS13Life (Rev’s)245L [C 0065001260025008800x 10 6Ca dynamic load rating (N) [for acme nuts, see design loadcolumn on catalog pages].25 mm LIFE EXPECTANCYFm average axial load (N).Example: For 10 mm pitch screw, 16 mm dia., Ca 4200 Ncarrying an average axial load, Fm 200 N (45 lbs) the expected life is:8L 934200 x 10 6 9.261 x 10 9 revolutions.200Life (Rev’s)At an average of 1000 rpm this will result in:9.261 x 10 9 revolutions1000 rpmx1 hour60 minutes 154,000 hoursof expected operational life. Note that the nature of the motion (jerky,smooth, etc.) will affect the life expectancy.1112Axial Load N131415161616162516251625L life expectancy expressed in number of revolutions7102.545510102020Axial Load (N)Dynamic (Ca)StaticFmAxial Load N6PitchScrewDia.9-24
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRLead Screw Formulas and Sample Calculations:TLinear Speed (ipm)steps / second1Linear Speed –––––––––––––––– x 60 x –––steps / revolutionpwhere:p lead screw pitch in threads per inch1Axial Force (lb)2πForce –––– x T x p x eff.16where:T torque (oz. in.)p lead screw pitch in threads per incheff. efficiency expressed as a decimal: 90% 0.9023Note: Ball screws are generally 85% to 95% efficient. Acme lead screw efficiency is generally 35% to 45%, but can be ashigh as 85%.A. Calculating the torque required to accelerate a mass moving horizontally and driven by a ball bearing lead screw andnut. The total torque the motor must provide includes the torque required to:a.b.c.d.accelerate the weightaccelerate the lead screwaccelerate the motor rotorovercome the frictional forcewMOTOR456To calculate the rotational equivalent of weight w:721 x (–––)1I(eq) w x –––p22πwhere:w weight (lb.)p pitch (threads per inch)I(eq) equivalent polar inertia (lb. in.2)89to calculate lead screw inertia (steel screw)4I (screw) D x length x .02810Example:Weight 1000 lb.Velocity 0.15 feet per secondTime to Reach Velocity 0.1 secondsBall Screw Diameter 1.5 inchesBall Screw Length 48 inchesBall Screw Pitch 5 threads per inchMotor Rotor Inertia 2.5 lb in.2Friction Force to Slide Weight 6 oz.111211I (eq) w x –––x .025 1000 x ––– x .025 1.0 lb. in.2p22513I (screw) D 4 x length x .028 5.06 x 48 x .028 6.8 lb in.2I (rotor) 2.5 lb. –––––––––––––––I (total) 10.3 lb. in.21415Velocity is 0.15 feet per second, which is equal to 1800 steps per second (motor steps in 1.8 increments).?-?9-2516
IRTBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMTorque to accelerate system:π x 1.8 '118003.1416 x 1.81T 2 x IO x ––– x –––––––– x ––– 2 x 10.3 x ––––– x –––––––––––– x ––– 484 oz. in.t180240.118024Torque to overcome friction:F .393 x T x p x eff.123456––––F16T ––––––––––––– ––––––––––––– 0.22 oz. in.393 x p x eff.393 x 5 x 0.90where:F frictional force (lb.)T torque (oz. in.)p lead screw pitch (threads per inch)Total torque required 0.22 oz. in. 484.00 oz. in. 484.22 oz. in.After determining the required motor size, it is recommended to add a 20% factor of safety so that unexpected dynamicloads are easily handled by the motor.Sizing Servo Motors:Two separate torque figures are needed when selecting a DC motor — a peak torque, being the sum of acceleration andfriction torques, and a continuous torque, which is the friction component only. The torque produced by the motor is given by:T Kτ I678where K is the motor torque constant (e.g., Nm/amp) and I is the drive current (amp). The choice of motor and drive mustsatisfy the following conditions:1. The product of K τ and peak drive current must give the required peak torque.2. The product of K τ and continuous drive current must produce sufficient continuous torque.3. The maximum allowable motor current must be greater than the peak drive current.4. At maximum speed and peak current, the voltage developed across the motor must be less than 80% of thedrive supply voltage.The voltage across the motor is given by: E KE R I9where KE is the motor voltage constant, the speed, R the winding resistance (ohms) and I the peak current (amperes).The speed units should be the same in each case; i.e., if the voltage constant is in volts per radian per second, then should also be in radians per second.10To make the most efficient use of the drive, the chosen solution should utilize most of the peak drive current and most ofthe available voltage. Motor manufacturers usually offer alternative windings, and care should be taken to select the mostappropriate.111213141516Example:Leadscrew Length: 80 in.Leadscrew Diameter: 1.5 in.Leadscrew Pitch: 2.54 in.Table Weight: 1000 lb.Linear Table Speed Required: 472 inches/min.Acceleration Time: 120 msD4LInertia of Leadscrew: J ––––– 11.25 lb. in.236WInertia of Table: J –––––– 3.88 lb. in.240 p 2Total inertia 15.13 lb. in.2Maximum Speed 472"/min. 1200 rpm (equivalent to 4000 full steps/sec)9-26Linear Table Driven by DC Motor
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMAcceleration Torque:RJ T ––––– 660 oz. in. (4.65 N m)764tThis takes no account of motor inertia, so a suitable motor will be capable of producing around 1000 oz in. torque.Again, as with stepper selection, it is recommended to add a 20% factor of safety so that unexpected dynamic loads areeasily handled by the motor.Bending Formulas for Extruded Profiles:The deflection of a beam depends on how it is supported, the magnitude of the load it carries, the distribution of the loadand the distance from the supports. Two examples will be considered — the simple beam and the cantilevered beam.T123The deflection of a simple beam with the load concentrated at the center is given by the following equation:Py 4Pl 348 EIl5The deflection of a cantilevered beam with the load concentrated at the free end is given by the following equation:y 6PPl 33 EIlwhere:yPlxEI 7beam deflection at the loading point, cmconcentrated loads, kgflength of beam, cmdistance from support to any section, cmmodulus of elasticity, kg/cm2moment of inertia, cm489Example 1:Structural Profile 40 x 80 is used as a simple beam with 100 cm between supports. If this beam carries a 100 kg load concentrated at the center of the beam, how much will the beam bend?10The modulus of elasticity of the aluminum alloy used for all the extrusions listed as example is 702,949 kg/cm. The momentof inertia for this beam is given which describes this beam. Since this beam is not symmetrical, two moments of inertia aregiven. Select the value corresponding to the way in which the beam will be used. For this example, we assume that the loadis applied along the y-axis. The moment of inertia is 21.17 cm4.11Substituting these values and the values from the example into the equation for the deflection of a simple beam, we obtain:100 kg (100 cm)3y 0.14 cm48 (702949 kg/cm2) (21.17 cm4)1213Example 2:Structural Profile 40 x 80 is supported at one end and a concentrated load is applied to the free end, 100 cm from the fixedend. Calculate the bending at the free end.Substituting these values and the value for the modulus of elasticity and moment of inertia above, we obtain:100 kg (100 cm)3y 2.24 cm3 (702949 kg/cm2) (21.17 cm4)?-?9-27141516
IBALL & ACME LEAD SCREW TECHNICAL INFORMATIONPHONE: 516.328.3300 FAX: 516.326.8827 WWW.SDP-SI.COMRTBall and Acme Screw Application WorksheetName:Phone:Company Name:Fax:1Address 1:2City:Address 2:State:Zip code:Brief Description of Application:345678Email:Max. Load:Max: Speed:Max. Accel:Travel:Complete Cycle Time:Orientation:Accuracy Needed:(please circle)91011Anti-Backlash Nut Required: YES or NOIntegral Flange Nut Required: YES or NOFinished End Required: YES or NOSupply drawing (Note: Finished ends for OEM quantities onlyi.e, 25 or higher)End Bearing Required: YES or NOBase Mount of Flange Mount of End Bearings:12131415169-28please use this for any notes or diagrams
MATERIAL: Turcite X (Acetal, PTFE & Silicone Filled) TEMPERATURE RANGE: 32 F to 160 F FEATURES: Lightweight Low cost Low friction Self-lubricating Up to 75,000,000 inches of travel Left-hand threads available on special order For use with Acme Lead Screw AB11SA-. FLANGE MOUNT ACME NUTS
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Acme Packet 1100 Acme Packet 3900 Acme Packet 4600 front bezel hides the fan assemblies without restricting airflow through the system. Acme Acme Packet 6100 Acme Packet 6300 Packet 6300 Acme Packet 6350 The rear of Acme Packet 6300 least one slot reserved for an NIU.
1- start acme screw from Tr 18 4 to Tr 100 16 1- start acme screw from Tr 18 4 to Tr 160 16 2-starts acme screw from Tr 18 8 (P4) to Tr 100 32 (P16) 2-starts acme screw from Tr 18 8 (P4) to Tr 160 32 (P16) Screw jacks MA Series Model A with travelling screw: 3- or 4-starts acme screws available
2 SDP Educator Diagnostic for Delaware Department of Education THE STRATEGIC DATA PROJECT (SDP) MISSION AND VISION Since 2008, SDP has partnered with 75 school districts, charter school networks, state agencies, and nonprofit organizations to . Part of the Center for Education Policy Research at Harvard University, SDP was formed on two .
Acme Packet 1100 and 3900 Security Policy Page 1 of 32 1. Introduction 1.1 Overview This document is the Security Policy for the Acme Packet 1100 [1] and Acme Packet 3900 [2] appliances manufactured by Oracle Communications. Acme Packet 1100 [1] and Acme Packet 3
ACME Acme Screw Threads, General Purpose B1.5 ACME-C Acme Screw Threads, Centralizing B1.5 STUB ACME Stub Acme Screw Threads B1.8 BUTT Buttress Inch Screw Threads 7 /45 B1.9 ANSI / AMO Microscope Objective Thread B1.12 AWWA Underground Service Line Valves and Fittings C800-84 DIN German Specifications .
4. All Acme nut thread remnants were positioned on the Acme screw in a measured range that corresponds with the Acme nut at the takeoff trim position of the aircraft8. 5. Some Acme nut thread remnants were found on the Acme nut screw in a measured range that corresponds with the Acme nut at the 0.37º aircraft nose down trim position9. 6. There .
Texts of Wow Rosh Hashana II 5780 - Congregation Shearith Israel, Atlanta Georgia Wow ׳ג ׳א:׳א תישארב (א) ׃ץרֶָֽאָּהָּ תאֵֵ֥וְּ םִימִַׁ֖שַָּה תאֵֵ֥ םיקִִ֑לֹאֱ ארָָּ֣ Îָּ תישִִׁ֖ארֵ Îְּ(ב) חַורְָּ֣ו ם
