Tooth thickness Dedendum. Addendum. Centre distance Nominal

Similar documents
Gear Engineering Data. Spur Gear Gear Formulas Drive Selection Horsepower and Torque Tables

Gear Tooth Geometry - This is determined primarily by pitch, depth and pressure angle

1.8 Rack shift of the gear

PRECISION GROUND GEARS Spur & Helical Gears

General gear terms and definitions. Trantorque 48 DP. Steel and Brass

1.7 Backlash. Summary of the backlash is play or clearance between one pair of gear. Fig. 17 Backlash

Mechanism Feasibility Design Task

Engineering Information

Fig. 1 Two stage helical gearbox


1/2/2015 2:04 PM. Chapter 13. Gears General. Dr. Mohammad Suliman Abuhaiba, PE

Sheet 1 Variable loading

12/6/2013 9:09 PM. Chapter 13. Gears General. Dr. Mohammad Suliman Abuhaiba, PE

KINGS COLLEGE OF ENGINEERING DEPARTMENT OF MECHANICAL ENGINEERING

Lecture (7) on. Gear Measurement. By Dr. Emad M. Saad. Industrial Engineering Dept. Faculty of Engineering. Fayoum University.

Bevel Gears n A Textbook of Machine Design

Spur gearing, Helical gearing [mm/iso] Pinion Gear ii Project information? i Calculation without errors.

1.6 Features of common gears

Chapter 1 Gear Design

ENGINEERING INFORMA TION

Internal Gears. No. of teeth (60) Module (1) Others (Ring Gear) Type (Internal Gear) Material (S45C)

GEAR CONTENTS POWER TRANSMISSION GEAR TYPES OF GEARS NOMENCLATURE APPLICATIONS OF GEARS VELOCITY RATIO GEAR TRAINS EXAMPLE PROBLEMS AND QUESTIONS

Bevel Gears. Fig.(1) Bevel gears

10.2 Calculation for Bevel gear strength

Program Internal Gear Set Profile Shift Coefficients With Zero Backlash Introduction

Helical Gears. Section Contents

CHENDU COLLEGE OF ENGINEERING & TECHNOLOGY DEPARTMENT OF MECHANICAL ENGINEERING QUESTION BANK

Chapter 8 Kinematics of Gears

Direction of Helix (R) No. of Teeth (20) Module (1) Others (Ground Gear) Type (Helical Gear) Material (SCM440)

(POWER TRANSMISSION Methods)

Chapter 3. Transmission Components

Spiroid High Torque Skew Axis Gearing A TECHNICAL PRIMER F. EVERTZ, M. GANGIREDDY, B. MORK, T. PORTER & A. QUIST

CH#13 Gears-General. Drive and Driven Gears 3/13/2018

EXAMPLES GEARS. page 1

Therefore, it is the general practice to test the tooth contact and backlash with a tester. Figure 19-5 shows the ideal contact for a worm gear mesh.

A comparison of the gear calculation process according to Swedish and American textbooks for higher education

Basic Fundamentals of Gear Drives

ISO INTERNATIONAL STANDARD. Bevel and hypoid gear geometry. Géométrie des engrenages coniques et hypoïdes. First edition

4.2 Method of measurement with Over balls or Rollers

Lecture 13 BEVEL GEARS

Catalog Q Conversion For those wishing to ease themselves into working with metric gears

Instantaneous Centre Method

QUESTION BANK Chapter:-6 Design of IC Engine Components

KH Hypoid Series Precision Range Steel

Customer Application Examples

Gear Measurement. Lecture (7) Mechanical Measurements

T25 T25 T25 T27 T27 T28 T28 T28 T28 T29 T29 T29 T31 T37 T37 T38 T T T48

Metrology Prof. Dr Kanakuppi Sadashivappa Bapuji Institute of Engineering and Technology Davangere. Lecture 25 Introduction of Gears

This table is offered as a guide only and does not take specific applications into account x kw kw = 0,746 x CV Nm = rpm

Chain Drives. Pitch. Basic Types -There are six major types of power-

Introduction to Gear Design

Bevel Gears. Catalog Number of KHK Stock Gears. Bevel Gears M BS G R. Gears. Spur. Helical. Gears. Internal. Gears. Racks. CP Racks.

Bevel and hypoid gear geometry

SECTION 4 SPUR GEAR CALCULATIONS

KINEMATICS OF MACHINARY UBMC302 QUESTION BANK UNIT-I BASICS OF MECHANISMS PART-A

CHAPTER 5 PREVENTION OF TOOTH DAMAGE IN HELICAL GEAR BY PROFILE MODIFICATION

Technology of Machine Tools

Unit IV GEARS. Gallery

DUDLEY'S" HANDBOOK OF PRACTICAL GEAR DESIGN AND MANUFACTURE. Stephen P. Radzevich

Spur Gears. Helical Gears. Bevel Gears. Worm Gears

1 135 teeth to rack

The Geometry of Involute Gears

Part VII: Gear Systems: Analysis

Bibliography. [1] Buckingham, Earle: "Analytical Mechanics of Gears", McGraw-Hill, New York, 1949, and republished by Dover, New York, 1963.

we will learn how to conduct force and torque analysis on gears in order to calculate bearing

KISSsoft 03/2017 Tutorial 15

REVIEWED BY CAPITAL PROJECTS MANAGER (DAN REDDY) AUTHORIZED BY CEO DESCRIPTION OF REVISION APPROVAL

Effect of Geometry Factor I & J Factor Multipliers in the performance of Helical Gears

MMS Spiral Miter Gears. SMS Spiral Miter Gears. m1 ~ 8 Page 268. SAM Angular Miter Gears. m1 ~ 4 Page 278. Direction of Spiral ( R )

Determination and improvement of bevel gear efficiency by means of loaded TCA

CHAPTER 3 page 35 PRINCIPLES OF GEAR-TOOTH GENERATION. .1 Angular Velocity Ratio

Introduction. Kinematics and Dynamics of Machines. Involute profile. 7. Gears

AG Worm Wheels Reduction Ratio 10 ~ 60. AGF Worm Wheels. Series. Newly added. m2 ~ 6 Page 358. DG Plastic Worm Wheels. SUW Stainless Steel Worms

UNIT -I. Ans: They are specified by the no. of strands & the no. of wires in each strand.

Power transmission. Components used to transmit power: gears, belt, clutch and brakes. Gear (Stresses) act on the tooth Lewis formula and AGMA

SPROCKET ENGINEERING DATA

DESIGN AND ANALYSIS OF HELICAL GEAR

Code No: R Set No. 1

KISSsoft 03/2013 Tutorial 15

INVOLUTE SPIRAL FACE COUPLINGS AND GEARS: DESIGN APPROACH AND MANUFACTURING TECHNIQUE

Power Transmission Elements II: Gears and Bearings. Lecture 3, Week 4

Design and Assembly Analysis of a Worm-Assembly in a Gear Box

Chapter seven. Gears. Laith Batarseh

Martin Sprocket & Gear, Inc.

ME6601 DESIGN OF TRANSMISSION SYSTEMS

HepcoMotion MHD Heavy Duty Track Roller Guidance System

WEIGHT. Reduction ratio 2:1 3:1 4:1 5:1 6:1 7:1. Max Input Speed

5 Project Planning for Gear Units

FZG Rig-Based Testing of Flank Load-Carrying Capacity Internal Gears

ANALYSIS OF SURFACE CONTACT STRESS FOR A SPUR GEAR OF MATERIAL STEEL 15NI2CR1MO28

SPROCKET ENGINEERING DATA

GEARING. Theory of. Stephen. Kinetics, Geometry, and Synthesis. P. Radzevich. /Ov CRC Press yc*** J Taylor& Francis Croup Boca Raton

What are the functions of gears? What is gear?

Metric Standards Worldwide Japanese Metric Standards In This Text

UNIT -1 TRANSMISSION SYSTEMS USING FLEXIBLE ELEMENTS. 1. What are the factors controlling selection of a transmission drive?

Thermal Analysis of Helical and Spiral Gear Train

ScienceDirect A NEW EXPERIMENTAL APPROACH TO TEST OPEN GEARS FOR WINCH DRUMS

4 Project Planning for Gear Units

Heavy-Duty Rod Ends - Male with integral spherical plain bearing

PRODUCTS AND SERVICES 2017

Transcription:

FORMULAS SPUR GEARS TO FIND:- PCD ØD MODULE No. of TEETH CP ADDENDUM DEDENDUM MODULE No. of TEETH x MOD (mm) (No. of TEETH + ) x MOD (mm) 5.4 MODULE CP π (mm) PCD MODULE (mm) MODULE x π (mm) MODULE (mm) 1.4 x MOD 1.5 x MOD (0.5-1 MOD) (1.5-8 MOD) IMPERIAL No. of TEETH (ins) No. of TEETH + (ins) π CP 5.4 PCD x π (ins) 1 (ins) 1.4 (-4 ) 1.5 (-6 ) CORRECTED TEETH FOR 8-17 TEETH ON REQUEST OR WHERE LISTED Corrected PCD Corrected ØD 7. 48 (No. of Teeth + 1) x MOD [(No. of Teeth + 1) / ] (No. of Teeth + 3) x MOD [(No. of Teeth + 3) / ] Our SPUR GEARS are made to give 0.07-0.3* Approx. backlash at standard centres. Housing centres should be nominal +0.00 +0.05mm. PCD (A) + PCD (B) FROM NOMINAL CENTRES mm 0.005 0.0 0.015 0.0 0.05 0.0 0.035 0.0 0.045 0.050 * Depends on pitch INCREASE IN BACKLASH mm 0.0037 0.0074 0.0111 0.0148 0.0185 0.01 0.059 0.095 0.038 0.0370 Whole depth Addendum + Dedendum Tooth thickness Dedendum Addendum Centre distance Nominal +0.00 +0.05 Outside Diameter Whole depth PCD A PCD B CP Root clearance

FORMULAS HELICAL GEARS TO FIND:- MODULE IMPERIAL P.C.D. ØD (NORMAL) MODULE No. of TEETH CP (NORMAL) ADDENDUM Lead No. of TEETH x MOD (mm) COS. HELIX )< PCD + ( x MOD) (mm) 5.4 MODULE CP (mm) π PCD x COS. )< (mm) MODULE MODULE x π (mm) MODULE PCD x π TAN )< Made to give 0.07-0.3mm* approx. backlash at standard centres. Housing centres should be nominal +0.00 - +0.05mm. No. of TEETH (ins) x COS. HELIX )< PCD. + π CP 5.4 ( x COS. )< ) x PCD π (ins) 1 (ins) Where HELIX )< HELIX Angle CROSSED AXIS * dependent on pitch LEFT hand runs with LEFT hand. RIGHT hand runs with RIGHT hand. DRIVER DRIVER DRIVER DRIVER DRIVEN DRIVEN DRIVEN DRIVEN PARALLEL AXIS LEFT hand runs with RIGHT hand. DRIVER General Direction of Force DRIVEN 7. 49

LOAD CALCULATIONS SPUR & HELICAL SPUR GEARS, BSI 436 : 19 ALLOWABLE TANGENTIAL LOAD, P.A. Xb factor for strength WEAR Xc factor for wear Xc Z Sc F Y Strength factor lbs. K Z Zone factor Sc* Material rating (surface stress) Sb* Material rating (bending stress) STRENGTH K Pitch factor 0.8 power Xb Y Sb F lbs. F Face width (inches) 5.4 MOD 1N 0.48 lbs Allowable tangential teeth load lbs Torque lbs ins x pcd The lowest of the four values for pinion and wheel gives the gear rating. The normal rating for gears is based on 1 hours/day. HELICAL GEARS, BSI 436 : 19 Xb Xc Y Z Sc* Sb* K F α ALLOWABLE TANGENTIAL LOAD OF HELIX ANGLE, P.A. Factor for Strength Factor for Wear Strength Factor Zone Factor Material Rating (surface stress) Material Rating (bending stress) Pitch Factor 0.8 Power Face Width (inches) Helix Angle 5.4 MOD WEAR * Please refer to Material Strength page for values. 7. 50 Xc Z* Sc F K STRENGTH Xb Y* Sb F 1.33 Cos 17 45 1.6 0.75 Sec 17 45 0.86 Cos Cosine Sec Secant Torque lbs ins x.113 Torque Nm 1kg 1 lb 1N x.48.46 Torque Nm Torque lbs Ins.113 lbs. lbs. *for other helix angles multiply Z by 0.75 sec α *for other helix angles multiply Y by 1.33 cos α

SPEED FACTORS SPUR & HELICAL Xc FOR WEAR Rpm.5 13 6 0 500 0 0 0 00 00 5000 7000 00 1 4 6 8 1 18 4..14 1. 1.57 1.43 1.18 1.0 0.935 0.85 0.7 0.700 0.6 0.635 0.6 0.5 0.450 0.415 0.3 0.3 0.5. 1. 1.44 1.5 1.13 0.9 0.8 0.735 0.650 0.5 0.550 0.5 0.500 0.4 0.415 0.355 0.35 0.5 0.70 0. 1.65 1.44 1.14 0.97 0.90 0.73 0.64 0.585 0.5 0.4 0.4 0.45 0.0 0.3 0.35 0. 0. 0. 0.15 0.190 Xb FOR STRENGTH Rpm.6 14 50 0 500 0 0 0 00 00 5000 7000 00 RUNNING TIME (hours per day) 1.45 1.5 1.0 0.87 0.79 0.64 0.57 0.515 0.4 0.0 0.3 0.370 0.350 0.335 0.90 0.50 0.5 0. 0.190 0.165 1.31 1.15 0.90 0.79 0.7 0.58 0.5 0.470 0.415 0.3 0.350 0.3 0.3 0.5 0. 0.5 0.7 0.190 0.170 0.15 1.16 1.00 0.78 0.68 0.63 0.51 0.45 0.4 0.3 0.3 0.5 0.90 0.70 0. 0. 0.195 0.1 0.165 0.150 0.1 1.00 0.86 0.67 0. 0.54 0.43 0.39 0.350 0.3 0.70 0. 0.50 0. 0. 0. 0.170 0.155 0.145 0.1 0.115 1 3 6 1 4 1.06 1.00 0.90 0. 0.70 0.65 0.6 0.0 0.55 0.435 0.4 0.415 0.4 0.385 0.35 0.85 0. 0. 0.15 0.19 RUNNING TIME (hours per day) 0.9 0.86 0.76 0.69 0.61 0.56 0.53 0.5 0.45 0.0 0.3 0.370 0.345 0.3 0.85 0.45 0.5 0.8 0.185 0.165 0.8 0.77 0.69 0.63 0.55 0.51 0.48 0.4 0.5 0.3 0.345 0.3 0.3 0.95 0.55 0. 0. 0.185 0.165 0.148 0.73 0.70 0.63 0.57 0.48 0.46 0.43 0.4 0.3 0.3 0.3 0.0 0.85 0.70 0. 0. 0.18 0.168 0.150 0.135 0.90 0.78 0.6 0.54 0.48 0. 0.35 0.3 0. 0.50 0. 0. 0. 0. 0.1 0.155 0.145 0.13 0.118 0.5 0.67 0.64 0.57 0.5 0.45 0.4 0.39 0.375 0.3 0.95 0.85 0.75 0.55 0.45 0. 0.1 0.165 0.15 0.138 0.1 7. 51

ZONE FACTORS SPUR & HELICAL SPUR GEARS, P.A. Z No. of NUMBER OF TEETH ON PINION Teeth in Gear 0 150 50 6 15 1 1 15 6 50 150 0 Rack 7. 5 1.09 1. 1.84.48 3.09 3.50 4.7 4.95 5. 7.00 8.00 1.08 1.38 1.79.39.94 3.3 3.95 4.58 5.11 6.14 6.88 8.3 1.08 1.36 1.75.3.85 3.16 3.79 4. 4.81 5.6 6.34 7.44 8.3 1.07 1.34 1.69..64.90 3.50 3.84 4.1 5.00 5.51 6.34 6.88 8.00 9.70 1.07 1.3 1.64.1.53.76 3.7 3.65 3.89 4.57 5.00 5.6 6.14 7.00 8. 1.06 1.8 1.58.00.36.54.93 3.8 3.57 3.89 4.1 4.81 5.11 5. 6.50 1.05 1.6 1.53 1.89.3..76 3.00 3.8 3.65 3.84 4. 4.58 4.95 5.50 1.05 1.5 1.48 1.75.06..53.76.93 3.7 3.50 3.79 3.95 4.7 4.65 1.04 1.4 1.43 1.68 1.88 1.98...54.76.90 3.16 3.3 3.50 3.70 1.03 1. 1.41 1.63 1. 1.88.06.3.36.53.64.85.94 3.09 3. HELICAL GEARS FOR HELIX ANGLE, P.A. 1.0 1.19 1.34 1.53 1.63 1.68 1.75 1.89.00.1..3.39.48.55 0.97 1. 1.1 1.34 1.41 1.43 1.48 1.53 1.58 1.64 1.69 1.75 1.79 1.84 1.90 For other helix angles, multiply zone factor by 0.75 x Sec helix angle. 0.9 1.01 1. 1.19 1. 1.4 1.5 1.6 1.8 1.3 1.34 1.36 1.38 1. 1.47 0.85 0.9 0.97 1.0 1.03 1.04 1.05 1.05 1.06 1.07 1.07 1.08 1.08 1.09 1.1 NOTE 0.75 x Sec 17 45 0.86 No. of NUMBER OF TEETH ON PINION Teeth in Gear Rack 0 150 50 6 15 1 1 15 6 50 150 0 Rack.03.35. 3.43 4.7 4.89 6.11 7.47 8.4.88 1.95.6.70 3.35 4. 4.69 5. 6.74 7.38 8.89.67 1.88.19.61 3.4 3.90 4.47 5.48 6. 6.83 7.94 9.6 11. 1.85.16.55 3.18 3. 4.7 5.18 6.00 6.50 7.50 8..00 11. 1.76.06.44 3.00 3.58 3.95 4.7 5.41 5.83 6.70 7.35 8.4 9.17.55 1.74 1.99.36.90 3.4 3.76 4.44 4.94 5.35 6.15 6.71 7.50 8.00 9.11.9 1.64 1.89.5.70 3.14 3.46 3.98 4.47 4.76 5.4 5.88 6.50 6.88 7.48 8.50 1.58 1.81.16.56.96 3. 3.70 4.18 4.39 4.94 5.36 5.9 6. 6.67 7.34 1.50 1.71.01.39.74.93 3.34 3.70 3.93 4.4 4.67 5.07 5.33 5.68 6.00 1.45 1.61 1.83.16.44.61.9 3. 3.38 3.74 3.94 4.4 4.37 4.63 4.91 1. 1.55 1.74.03.9.44.7.94 3.1 3.41 3. 3.84 3.96 4.14 4.36 1.9 1.44 1.61 1.8.0.17.38.55.66.87.97 3.17 3.5 3.35 3.44 1.18 1.8 1.43 1. 1.73 1.83.00.14..36.43.5.68.69.81 1.09 1.17 1.9 1.43 1.54 1. 1.7 1.81 1.87 1.98.05.14.19.6.36 1.00 1.09 1.18 1.7 1.38 1.45 1.5 1.58 1.64 1.75 1.78 1.84 1.88 1.94 Z

STRENGTH FACTORS SPUR & HELICAL HELICAL GEARS WITH HELIX ANGLE, P.A. AND P.A. SPUR GEARS For other helix angles, multiply zone strength by 1.33 x Cos helix angle. NOTE: 1.33 x Cos 17 45 1.6 No. of NO. OF TEETH ON MATING GEAR OR PINION Teeth in Gear Rack 0 150 50 6 15 1 1 15 6 50 150 0 Rack.0.658.714.770.813.838.876.900.913.98.931.9.98.94.585.639.697.750.790.813.854.87.883.896.897.893.889.88.869.5.6.687.738.776.796.837.858.865.875.875.870.867.861.850.579.65.681.731.768.788.84.848.856.863.864.858.855.850.839.575.618.670.7.753.77.3.8.833.839.8.835.833.88.8 The zone factor (Z) is a factor dependent on the total contact between mating teeth and the radii of curvature of the tooth surfaces. Internal Gears - The zone factor for internal gears shall be equal to that for the same combination of external teeth multiplied by:- ( R + 1 ) 0.8 Power RRatio R 1.573.614.664.713.74.759.788.6.815.81.8.8.818.814.8 The Strength Factor (Y) is a factor dependent on the number of teeth in contact, the cantilever strength of an individual tooth, and the distribution of load over the face of the tooth. Internal Gears - The strength factor for the pinion gearing with an internal gear shall be the same as that for a pinion of the same number of teeth gearing with a rack. The strength factor for the internal gear shall be the same as that of a rack gearing with a pinion having the same number of teeth as the actual pinion, multiplied by:- (1 + 3) T where T is the number of teeth in the internal gear..568.5.653.698.75.738.761.776.783.791.793.7.793.791.789 Idler Gears The idler gears in which the teeth make contact on one side with the driving gears and on the other with the driven gears, should be calculated on the.566.0.646.686.699.716.736.75.758.765.767.770.771.77.767.563.597.638.677.671.677.693.705.716.78.734.7.743.747.755.561.593.631.65.633.63.64.644.654.673.683.697.703.713.78.558.591.66.64.67.611.7.6.6.645.661.676.681.695.714.554.585.617.66.614..574.58.590..613.68.638.654.684.548.573.598.5.595.58.555.544.549.56.571.584.591.7.64.54.56.5.579.57.5.535.517.53.533.541.55.561.576.6 Y.533.550.563.56.551.543.518.490.500.511.518.533.537.550.58 normal basis for wear, but the speed co-efficient used in calculating the load capacity for strength must be half the normal value. Multiple Contact - If a gear makes contact on the same set of flanks with more than one other gear, the equivalent running time per day is to be taken as the sum of those applying to the separate mating gears. GEAR LUBRICATION Given the variety of gear types, service requirements, environmental influences and service temperature ranges, the choice of lubricant is an important factor for the service reliability and service life of the machine concerned. The following are recommended, on the basis of DIN 51 509 (Selection of Lubricants for Gears):- 1. At peripheral velocities up to v m/s: High-consistency adhesive lubricants are used on large open gears.. At peripheral velocities up to v 4 m/s: Here, splash-lubrication using a soft gear-grease is customary into which the gear wheel dips 3. At peripheral velocities up to v 15 m/s: Here it is oil splash-lubrication which predominates 4. At peripheral velocities above v 15 m/s: In this range, oil spray lubrication is required in most cases. 7. 53

FORMULAS BEVEL GEARS TO FIND:- PINION WHEEL PCD PITCH ANGLE (for 90 shaft angle) PITCH ANGLE (for shaft angle <90 ) PITCH ANGLE (for shaft angle > 90 ) n d or n x mod (ins) (mm) n No. of teeth. -1 n Y tan (deg) N -1 sin Σ Y tan N [( + cos Σ n ) ] [ ] Σ SHAFT ANGLE -1 sin (1 Σ) Y tan N cos (1 Σ) n N D or N x mod (ins) (mm) N No. of teeth. Γ 90 Y (deg) Γ Σ Y Γ Σ Y D CONE DISTANCE Ao See Pinion * see note sin Γ * A pitch angle (Σ) greater than 90 indicates an internal gear. Please contact Technical to determine if the gear can be cut. FORMULAS - WORMS & WHEELS TO FIND:- MODULE IMPERIAL ØD TANGENT OF THE LEAD ANGLE CENTRE DISTANCE TO FIND:- MODULE IMPERIAL THROAT Ø (No. of TEETH + ) x MOD (mm) No. of TEETH + (inches) TIP Ø P.C.D. REDUCTION RATIO ( x MODULE) + PCDmm MODULE x No. of STARTS PCD PCD (Worm) + PCD (Wheel) in mm (No. of TEETH + 3) x MOD (mm) No. of TEETH x MOD (mm) No. of TEETH in WHEEL No. of STARTS in WORM PCD (WORM) + PCD (WHEEL) CENTRE DISTANCE + PCD CP x No. of STARTS PCD x π PCD (Worm) + PCD (Wheel) No. of TEETH + 3 (inches) No. of TEETH (inches) Our WORMS and WORMWHEELS are made to give 0.08-0.15mm backlash at standard centres. Housing centres should be nominal +0.00 +0.05mm. 7. 54

LOAD CALCULATIONS BEVELS BEVEL GEARS, BSI 545 : 1949 Xc Z Sc* Sb* K F Xb Y C P Based on 1 hour day. Cone Distance C ALLOWABLE TANGENTIAL LOAD AT PITCH RADIUS factor for wear Zone factor (see chart) Material rating (surface stress) Material rating (bending stress) Pitch factor 0.8 power Face width (inches) for strength Strength factor Cone distance (inches) PCD" of Gear x Sin Pitch Angle of Gear Allowable tangential load at PCR Torque lbs ins x PCD Pitch Angle of Gear 90 Pitch Angle of Pinion Pitch Angle of Pinion tan 1 No. of Teeth Pinion No. of Teeth Gear WEAR Xc Sc Z F C - F x K x 1.33 1.1 x C STRENGTH Xb Sb Y F C - F x P ( 1.1 x C) lbs ( ) lbs. lbs. The lowest of the four values for pinion and wheel gives the gear rating. The normal rating for gears is based on 1 hours/day. hrs per day Approx. 0 0.5 1 3 6 1 4 Total hours life 0 0 5000 00 0 50 Wear multiply by 3.0.91.38 1.66 1.35 1.0 0.79 Strength multiply by.0 1.89 1.55 1.7 1.14 1.0 0.9 Gear torque allowable Tangential Load x PCD Allowable Tangential Load Gear Torque x PCD * Please refer to Material Strength page for values. 7. 55

BEVEL GEARS ZONE FACTORS Z 7. 56 maximum ratio 4:1 Gleason No. of NUMBER OF TEETH IN MATING GEAR Teeth in Gear 15 16 19 4 5 6 3 45 48 7 15 16 19 4 5 6 3 45 48 7 1. 1.850.050..45.50.55.350.3.450.500.0 1.850 1.950.35...65.65.455.500.650.700.7.050.35.0.355.0.0.650.750.755 3.000 3.000 3. 3.150...355.450.7.7.750.770.775 3. 3.0 3.350 3.0.45..0.7.850.900.950 3. 3.50 3.0 3.650 3.750 3..50.65.0.7.900.900 3.050 3.50 3.0 3.750 3.750 3. 3.950 STRENGTH FACTORS Y.55.65.650.750.950 3.050 3. 3.0 3.450 3. 3.850 4.000 4..350.455.750.770 3. 3.50 3.0 3.650 3.700 4. 4. 4.500 4.700.3.500.755.755 3.50 3.0 3.450 3.700 3.700 4. 4.0 4.700 4.850.450.650 3.000 3. 3.0 3.750 3. 4. 4. 5.000 5. 5. 5.950.500.700 3.000 3.0 3.650 3.750 3.850 4. 4.0 5. 5.0 5.900 6..0.7 3. 3.350 3.750 3. 4.000 4.500 4.700 5. 5.900 6.0 7.000 No. of NUMBER OF TEETH IN MATING GEAR Teeth in Gear 15 15.65.585.570.5.0.6.65.6.65.6.650.670.705.7.715.7.7.705.7.765.770.765.7 SPEED FACTORS Xc FOR WEAR.7.745.795.85.8.790.750.8.8.8.855 Rpm Xc Rpm Xc Rpm Xc Rpm Xc 1 4 6 8 1.00 0.88 0.77 0.70 0.67.635.550.485.4.45 0 0 0.375.3.3.85.75 0 00 00 0 00 SPEED FACTORS Xb FOR STRENGTH Rpm Xc Rpm Xc Rpm Xc Rpm Xc 1 4 6 8.66.64.6.59.58.570.55.4.4.45 0 0 0.375.3.3.85.75 0 00 00 0 00 3.150 3.0 3. 3.950 4. 4.700 4.850 5.950 6. 7.000 7.700..1.165.1.15..1.165.1.15

LOAD CALCULATIONS WORMS & WHEELS BSI 71 : 1937 TORQUE CAPACITY (based on 1 hour day) Xc factor for wear (see chart) 0.18 Constant value Sc Material rating - surface stress (see tables) Sb Material rating - bending stress (see tables) efw Effective face width of wheel Xb factor for strength 1.8 Constant value M Addendum in inches D Wheel PCD Lr Length at root of wheel teeth in inches Cosα Cosine of lead angle of worm WEAR 0.18 Sc Xc efw D 1.8 lbs. Ins. STRENGTH 1.8Sb Xb Lr M D Cosα L r e fw lbs. ins. Rubbing Feet/Minute Worm pcd x π x RPM 1 efw x Addendum ( Worm O/D Addendum ) x secant lead angle Lr x θ x Worm O/D Cosθ ( x 0.01745 PCD of Worm ) O/D of Worm Note : The lowest of the four values for Worm and Wheel gives the gear rating. Angle θ Cos -1 θ Wear Strength 1/6 1/4 1/ 1 3 4 6 8 18 4 0.50 0.38 0.54 0.4 0.56 RUNNING TIME (hours per day) Xc and Xb to be divided by factors below for different hrs/day 0.47 0.59 0.55 0.64 0.6 0.68 0.68 0.7 0.78 0.79 0.87 0.87 0.94 0.94 1.15 1.15 1.4 1.4 7. 57

SPEED FACTORS WORMS & WHEELS Xc FOR WEAR RPM of RUBBING SPEED (ft/min) Worm & Wheel 1 4 0 0 0 500 0 0 500.19.1.6.7.3.4.48.58.65.71.8.17.185.4.5.3.38.46.55.6.7.8.165.18.3.4.8.36.43.51.56.61.71.145.155.195.1.45.3.37.45.50.54.65.13.1.175.19.3.8.34..45.48.57.118.13.16.175...31.36.41.44.54.099.7.135.15.17..6.31.34.37.45.090.097.15.135.155..3.8.3.34.4.078.085.6.115.135.17..4.7.9.36 Xb FOR STRENGTH RPM Factor RPM Factor RPM Factor RPM Factor 0.5 90 0.4 500 0.3 00 0. 15 0.5 0.415 0 0.0 3500 0.190 0.5 150 0.384 700 0.90 00 0.1 0.500 0.365 0. 4500 0.175 0.4 50 0.350 900 0.70 5000 0.170 50 0.4 0 0.3 0 0. 00 0.1 0.450 350 0.335 1500 0. 7000 0.150 70 0.4 0 0.3 0 0.5 0 0.1 0.4 450 0.3 500 0. 9000 0.135 7. 58

BENDING AND SURFACE STRESS FACTORS WORMS & WHEELS Wheel WHEEL Materials Phosphor Bronze Sand Cast A Phosphor Bronze Chill Cast Phosphor Bronze Centrifugally Cast B Cast Iron (Gray) Worm C D E WORM Materials 0.4% Carbon Steel Normalised 0.55% Carbon Steel Normalised Low-carbon CasehardeningSteel 3.5% Nickel Casehardening Steel 5% Nickel Casehardening Steel 3.5% Nickel Chromium Casehardening Steel High Nickel-chrom Casehardening Steel Bending Stress Factor Sb Pounds per Sq. In. 7,000 8,500,000 6,000 Find surface stress factor Sc for wheel, under worm material classification letter A B C D E 900* 0* * 0* 0* 0 0 0 700 900 1 0 * HPC standard wheels use sand cast PB *For standard hardened worms use Sc value for wheels Bending Stress Factor Sb Pounds per Sq. In.,000,000 7,000,000 47,000 47,000 47,000 Find surface stress factor Sc for wheel, under worm material classification letter NOTE: Section E - hardened, ground and polished. HPC Standard Worms Unhardened - Sc Sb 17,000 Hardened - Sc 00 Sb 7,000 * Maximum permissible rubbing speeds, 500 feet per minute. Should not be used except for hand operated gearing. 0 A B C D E 0 00 6500 7000 7000 0 900 1 00 00 00 00 00 750 0 0 0 0 7. 59

EFFICIENCY WORMS & WHEELS Excluding bearing and oil churning losses. Values are based on PB Wheels and case hardened and ground and polished worms lubricated by mineral oil. The efficiency may be improved after the running in period. NOTE: As HPC standard worms are not hardened ground and polished lower efficiency values can be expected. TAN )< Efficiency (%) [ TAN (θ + )< ) ] X θ TAN -1 f )< Lead Angle f Coefficient of friction INPUT TORQUE Output Torque x Ratio Efficiency OUTPUT TORQUE Input Torque x Ratio x Efficiency Coefficients of Friction for Worm Gearing Rubbing Ft. per min. Coefficients of Friction Rubbing Ft. per min. Coefficients of Friction Rubbing Ft. per min. Coefficients of Friction Rubbing Ft. per min. Coefficients of Friction 50 70 90 1 1 1 1 150 1 170 0.073 0.070 0.066 0.06 0.0 0.058 0.056 0.054 0.05 0.051 0.050 0.049 0.048 0.047 0.046 1 190 5 50 75 0 35 350 375 0 45 450 475 500 0.045 0.044 0.043 0.041 0.0 0.038 0.036 0.035 0.034 0.033 0.033 0.03 0.031 0.0 0.0 550 0 650 700 750 850 900 950 0 1 1 1500 0.08 0.07 0.06 0.06 0.05 0.04 0.03 0.03 0.0 0.0 0.01 0.0 0.019 0.019 0.018 1700 1 1900 0 500 700 900 00 0.0175 0.0170 0.0165 0.0165 0.01 0.01 0.0155 0.0150 0.0150 0.0150 0.0145 0.0145 0.01 0.01 0.01 7.