The document discusses the design of various types of screw fasteners. It describes screw threads as helical grooves cut into cylindrical surfaces. Screw joints are commonly used for assembly and have advantages of being convenient to assemble/disassemble, reliable, and inexpensive due to standardization. The main types of screw fasteners are bolts, screws, studs, tapping screws, and set screws. Stresses in screw joints include tension, torsional shear, shear across threads, crushing stress, and bending stress. Screw joints are also subjected to stresses from initial tightening and external loads. Design considerations are discussed for bolted joints under eccentric loading parallel or perpendicular to the bolt axis.
1. Shaft couplings are used to connect shafts that are manufactured separately or to introduce flexibility between shafts. The main types are rigid and flexible couplings.
2. Rigid couplings transmit torque without losses but require perfectly aligned shafts. Flexible couplings allow for misalignment. Common rigid couplings are sleeve, clamp, and flange couplings.
3. Flange couplings use separate cast iron flanges keyed to each shaft end and bolted together. The flanges and bolts are designed to transmit the torque between the shafts. Flexible couplings like bush pin couplings introduce mechanical flexibility.
Mechanical Engineering Standard Design Data BookHiten Bhadja
This document provides a summary of key concepts and equations related to mechanical design data for various components including friction clutches, brakes, belt drives, chain drives, rolling contact bearings, sliding contact bearings, spur gears, helical gears, bevel gears, and worm gears. Key equations are presented for analyzing components like clutches, brakes, gear trains, and bearings. Design considerations related to factors like load capacity, power transmission, material properties, and component life are also discussed.
4 shaft problems on shaft bending moment onlyDr.R. SELVAM
1) The document discusses the design of solid and hollow shafts subjected to torque or bending moments. It provides examples of calculating the diameters of shafts based on the power transmitted, shear stress, bending stress, and other parameters.
2) Formulas are given for calculating the torque capacity and moment of inertia of solid and hollow circular shafts. Examples show how to use the formulas and given values like power, speed, stress limits, and safety factors to determine the necessary shaft diameters.
3) One example calculates the diameter of a railway axle between wheels based on the load on each wheel, distance of the load from the wheel base, gauge of the rails, and not exceeding a bending stress limit. Diagrams
Design of transmission systems question bank - GGGopinath Guru
This document contains questions related to the design of various transmission systems including belt drives, chain drives, gear drives, and rope drives. It provides a question bank with multiple choice and numerical questions on the design, selection and analysis of different types of flexible elements and rigid transmissions used to transmit power between rotating shafts. The questions cover topics such as the selection of V-belts and pulleys, flat belts and pulleys, wire ropes and pulleys, transmission chains and sprockets, as well as the design of gears, including spur gears, helical gears, and gear drives.
STRENGTH OF MATERIALS FOR MECHANICAL ENGINEERS-Unit-III-Torsion Dr.S.SURESH
This document discusses torsion and torsional rigidity in mechanical engineering. It defines torque as a measure of the force that can cause rotation about an axis. When a twisting force or torque is applied to an object, it causes torsion or twisting of the object. This results in shear stresses in the material of the object, such as a shaft. The torsional rigidity or stiffness of a shaft is defined as the product of its shear modulus and polar moment of inertia, which represents the torque required to produce a twist of one radian per unit length. The polar modulus, also called the torsional section modulus, is the ratio of the polar moment of inertia to the radius and is a direct measure of the
This document provides an overview of a seminar on the design of rolling-friction power screws (ballscrews) presented by students at Savitribai Phule Pune University. The seminar covers the history of ballscrews, introduces their classification, circulation, design considerations including preload calculation and stiffness. It discusses advantages like efficiency and smooth operation, disadvantages like cost and critical speed issues. Applications mentioned include automobile steering gears, CNC machines and aircraft landing gear. The conclusion discusses analytical models for friction torques and efficiency in ballscrew systems.
The document discusses different types of brakes and dynamometers. It describes various braking systems including frictional brakes, hydraulic brakes, and mechanical brakes. It also explains different types of dynamometers such as absorption dynamometers and transmission dynamometers. Absorption dynamometers completely absorb the engine's power through friction, while transmission dynamometers transmit power for measurement. Specific braking devices covered include band brakes, shoe brakes, and dynamometers like the Prony brake and rope brake. Formulas are provided for calculating braking torque and power measurements.
This document discusses balancing of rotating members. It begins by defining balancing as a process of restoring an unbalanced rotor to a balanced state by adjusting the rotor's mass distribution about its axis of rotation. It then lists various rotating components that require balancing, such as machine tool spindles, flywheels, impellers, and turbine rotors. The document explains that unbalance is caused by the displacement of a rotor's mass centerline from its axis of rotation. It discusses the benefits of balancing, such as reducing vibration, noise, and bearing wear. Finally, it covers the different types of unbalance - static and dynamic - and describes how to perform static and dynamic balancing procedures.
1. Shaft couplings are used to connect shafts that are manufactured separately or to introduce flexibility between shafts. The main types are rigid and flexible couplings.
2. Rigid couplings transmit torque without losses but require perfectly aligned shafts. Flexible couplings allow for misalignment. Common rigid couplings are sleeve, clamp, and flange couplings.
3. Flange couplings use separate cast iron flanges keyed to each shaft end and bolted together. The flanges and bolts are designed to transmit the torque between the shafts. Flexible couplings like bush pin couplings introduce mechanical flexibility.
Mechanical Engineering Standard Design Data BookHiten Bhadja
This document provides a summary of key concepts and equations related to mechanical design data for various components including friction clutches, brakes, belt drives, chain drives, rolling contact bearings, sliding contact bearings, spur gears, helical gears, bevel gears, and worm gears. Key equations are presented for analyzing components like clutches, brakes, gear trains, and bearings. Design considerations related to factors like load capacity, power transmission, material properties, and component life are also discussed.
4 shaft problems on shaft bending moment onlyDr.R. SELVAM
1) The document discusses the design of solid and hollow shafts subjected to torque or bending moments. It provides examples of calculating the diameters of shafts based on the power transmitted, shear stress, bending stress, and other parameters.
2) Formulas are given for calculating the torque capacity and moment of inertia of solid and hollow circular shafts. Examples show how to use the formulas and given values like power, speed, stress limits, and safety factors to determine the necessary shaft diameters.
3) One example calculates the diameter of a railway axle between wheels based on the load on each wheel, distance of the load from the wheel base, gauge of the rails, and not exceeding a bending stress limit. Diagrams
Design of transmission systems question bank - GGGopinath Guru
This document contains questions related to the design of various transmission systems including belt drives, chain drives, gear drives, and rope drives. It provides a question bank with multiple choice and numerical questions on the design, selection and analysis of different types of flexible elements and rigid transmissions used to transmit power between rotating shafts. The questions cover topics such as the selection of V-belts and pulleys, flat belts and pulleys, wire ropes and pulleys, transmission chains and sprockets, as well as the design of gears, including spur gears, helical gears, and gear drives.
STRENGTH OF MATERIALS FOR MECHANICAL ENGINEERS-Unit-III-Torsion Dr.S.SURESH
This document discusses torsion and torsional rigidity in mechanical engineering. It defines torque as a measure of the force that can cause rotation about an axis. When a twisting force or torque is applied to an object, it causes torsion or twisting of the object. This results in shear stresses in the material of the object, such as a shaft. The torsional rigidity or stiffness of a shaft is defined as the product of its shear modulus and polar moment of inertia, which represents the torque required to produce a twist of one radian per unit length. The polar modulus, also called the torsional section modulus, is the ratio of the polar moment of inertia to the radius and is a direct measure of the
This document provides an overview of a seminar on the design of rolling-friction power screws (ballscrews) presented by students at Savitribai Phule Pune University. The seminar covers the history of ballscrews, introduces their classification, circulation, design considerations including preload calculation and stiffness. It discusses advantages like efficiency and smooth operation, disadvantages like cost and critical speed issues. Applications mentioned include automobile steering gears, CNC machines and aircraft landing gear. The conclusion discusses analytical models for friction torques and efficiency in ballscrew systems.
The document discusses different types of brakes and dynamometers. It describes various braking systems including frictional brakes, hydraulic brakes, and mechanical brakes. It also explains different types of dynamometers such as absorption dynamometers and transmission dynamometers. Absorption dynamometers completely absorb the engine's power through friction, while transmission dynamometers transmit power for measurement. Specific braking devices covered include band brakes, shoe brakes, and dynamometers like the Prony brake and rope brake. Formulas are provided for calculating braking torque and power measurements.
This document discusses balancing of rotating members. It begins by defining balancing as a process of restoring an unbalanced rotor to a balanced state by adjusting the rotor's mass distribution about its axis of rotation. It then lists various rotating components that require balancing, such as machine tool spindles, flywheels, impellers, and turbine rotors. The document explains that unbalance is caused by the displacement of a rotor's mass centerline from its axis of rotation. It discusses the benefits of balancing, such as reducing vibration, noise, and bearing wear. Finally, it covers the different types of unbalance - static and dynamic - and describes how to perform static and dynamic balancing procedures.
Unit 2 Design Of Shafts Keys and CouplingsMahesh Shinde
This document provides information about the design of shafts, keys, and couplings. It discusses transmission shafts, stresses induced in shafts, and shaft design based on strength and rigidity. It presents formulas for shaft design using maximum shear stress theory, distortion energy theory, and the ASME code. Several examples are provided to demonstrate how to calculate the diameter of a shaft given the power transmitted, loads on the shaft, material properties, and other parameters using these theories and codes. Assignments involving similar calculations of shaft diameters are presented.
ME010 801 Design of Transmission Elements
(Common with AU010 801)
Teaching scheme Credits: 4
2 hours lecture, 2 hour tutorial and 1 hour drawing per week
Objectives
To provide basic design skill with regard to various transmission elements like clutches, brakes, bearings and
gears.
Module I (20 Hrs)
Clutches - friction clutches- design considerations-multiple disc clutches-cone clutch- centrifugal clutch -
Brakes- Block brake- band brake- band and block brake-internal expanding shoe brake.
Module II (17 Hrs)
Design of bearings - Types - Selection of a bearing type - bearing life - Rolling contact bearings - static
and dynamic load capacity - axial and radial loads - selection of bearings - dynamic equivalent load -
lubrication and lubricants - viscosity - Journal bearings - hydrodynamic theory - design considerations -
heat balance - bearing characteristic number - hydrostatic bearings.
Module III (19 Hrs)
Gears- classification- Gear nomenclature - Tooth profiles - Materials of gears - design of spur, helical,
bevel gears and worm & worm wheel - Law of gearing - virtual or formative number of teeth- gear tooth
failures- Beam strength - Lewis equation- Buckingham’s equation for dynamic load- wear loadendurance strength of tooth- surface durability- heat dissipation - lubrication of gears - Merits and
demerits of each type of gears.
Module IV (16 Hrs)
Design of Internal Combustion Engine parts- Piston, Cylinder, Connecting rod, Flywheel
Design recommendations for Forgings- castings and welded products- rolled sections- turned parts,
screw machined products- Parts produced on milling machines. Design for manufacturing - preparation
of working drawings - working drawings for manufacture of parts with complete specifications including
manufacturing details.
Note: Any one of the following data book is permitted for reference in the final University examination:
1. Machine Design Data hand book by K. Lingaiah, Suma Publishers, Bangalore/ Tata Mc Graw Hill
2. PSG Design Data, DPV Printers, Coimbatore.
Text Books
1. C.S,Sarma, Kamlesh Purohit, Design of Machine Elements Prentice Hall of India Ltd NewDelhi
2. V.B.Bhandari, Design of Machine Elements McGraw Hill Book Company
3. M. F. Spotts, T. E. Shoup, Design of Machine Elements, Pearson Education.
Reference Books
1. J. E. Shigley, Mechanical Engineering Design, McGraw Hill Book Company.
2. Juvinall R.C & Marshek K.M., Fundamentals of Machine Component Design, John Wiley
3. Doughtie V.L., & Vallance A.V., Design of Machine Elements, McGraw Hill Book Company.
4. Siegel, Maleev & Hartman, Mechanical Design of Machines, International Book Company
Design of Flat belt, V belt and chain drivesDr. L K Bhagi
Geometrical relationships, Analysis of belt tensions, Condition for maximum power transmission, Characteristics of belt drives, Selection of flat belt, V- belt, Selection of V belt, Roller chains, Geometrical relationship, Polygonal effect, Power rating of roller chains, Design of chain drive, Introduction to belt drives and belt construction, Introduction to chain drives
This document contains a question bank for the Design of Machine Elements course covering various topics in 5 units. It includes over 180 questions related to steady and variable stresses in machine members, shafts and couplings, joints, energy storing elements, and bearings. The questions cover topics such as stress analysis, materials selection, fits and tolerances, failure theories, stress concentration, fatigue design, and design of common machine components. The document also lists the textbook and references used for the course.
5 shaft shafts subjected to combined twisting moment and bending momentDr.R. SELVAM
1. The document discusses the design of shafts that are subjected to both twisting moments and bending moments.
2. It describes two theories for analyzing combined stresses: maximum shear stress theory for ductile materials like steel, and maximum normal stress theory for brittle materials like cast iron.
3. It provides an example of determining the diameter of a shaft made of 45 C 8 steel that is subjected to a bending moment of 3000 N-m and torque of 10,000 N-m, with a safety factor of 6.
This document discusses belt, rope, and chain drives used to transmit power between rotating shafts. It describes factors that affect the amount of power transmitted by belts, such as velocity, tension, and arc of contact. It also outlines conditions for proper belt use, types of belt drives based on power level, and sources of belt slippage. Additionally, it provides details on chain drives, including types of chains, construction, geometry considerations for sprockets and chain length, and recommended angle of contact.
The document discusses stresses in flywheel components and design considerations. It describes:
1. A flywheel consists of a rim to concentrate mass, a hub to attach to a shaft, and arms to support the rim.
2. Stresses induced in the rim include tensile stress from centrifugal force, tensile bending stress from arm restraint, and shrinkage stresses from uneven cooling.
3. The tensile stress in the rim from centrifugal force is calculated similarly to a thin cylinder under pressure. Stresses in the arms include tensile stress from centrifugal force and bending stress from transmitting torque.
Springs are elastic machine elements that deflect under load and return to their original shape when the load is removed. This document discusses the design of helical compression springs. It defines spring terminology such as mean diameter, spring index, solid length, and pitch. It presents the load-stress and load-deflection equations for spring design. It also discusses stresses in springs, series and parallel spring connections, surge, and the design procedure for helical springs. As an example, it solves a problem involving the design of concentric springs for an aircraft engine valve.
Spring is an elastic body whose function is to distort when loaded and to recover its original shape when the load is removed.
APPLICATION OF SPRINGS
To apply forces as in brakes, clutches and spring loaded valves.
To store energy as in watches, toys.
To measure forces as in spring balance and engine indicators.
To cushion, absorb or control energy due to either shock or vibration as in car.The material of the spring should have
high fatigue strength,
high ductility,
high resilience and
creep resistant.
It largely depends upon the size and service.
The strength of the wires varies with size, smaller size wires have greater strength and less ductility, due to the greater degree of cold working.
Severe service means rapid continuous loading where the ratio of minimum to maximum load (or stress) is one-half or less, as in automotive valve springs.
Average service includes the same stress range as in severe service but with only intermittent operation, as in engine governor springs and automobile suspension springs.
Light service includes springs subjected to loads that are static or very infrequently varied, as in safety valve springs.
The springs are mostly made from oil-tempered carbon steel wires containing 0.60 to 0.70 per cent carbon and 0.60 to 1.0 per cent manganese.
Springs are elastic bodies that store mechanical energy when compressed, stretched, or twisted by an external force. Common materials used for springs include various types of steel, copper alloys, and titanium. Springs can be arranged in series or parallel configurations, and the total spring constant of combined systems can be calculated. Different types of springs include helical, leaf, and disc springs, which are used for various purposes like absorbing shock, storing energy, and maintaining contact forces. Helical springs specifically can be tensional, compression, torsion, or spiral types.
Lecture 13 torsion in solid and hollow shafts 1Deepak Agarwal
The document discusses stresses in beams and shafts subjected to torsion. It covers torsional deformation of circular shafts, shear stresses and strains from torques, polar moment of inertia, torsional rigidity, and stresses in shafts under combined bending and torsion loads. Key formulas are presented relating torque to shear stress, polar modulus, bending stress, and principal stresses under combined loading. Applications to solid and hollow circular shafts and bars subjected to forces, bending moments, shear forces, and torques are described.
The document discusses gears and their classification. It defines various gear types including spur gears, helical gears, bevel gears, worm gears, and rack gears. It covers gear terminology such as pressure angle and describes how parameters like pressure angle and center distance affect gear performance and interference. Methods to avoid interference include increasing center distance, tooth modification, and changing the number of teeth. Backlash is also defined as the clearance between mating gear teeth.
Design and Analysis of Flange CouplingIJERA Editor
The approach utilizes standard design equations of these couplings and links them together in computer software to determine the design parameters of the couplings. In general, most flange coupling is available in transformation system and automobile industries. A flange coupling usually applies to a coupling having two cast iron flanges. To achieve a require goal, a design of bolted unprotected flange coupling is modeled in to a cad package named Solid works. Furthered the finite element analysis module is created in ANSYS Workbench by using ANSYS Static Structural module which has a predefined process to obtain optimum results.
spring, types, working and advantages and disadvantages.sannanshafiq
Springs are elastic bodies that distort under load and recover their original shape when unloaded. The major types of springs are helical, conical, torsion, laminated/leaf, and disc springs. Springs work based on Hooke's law, where the force is directly proportional to displacement from the original position. Springs have advantages of being easy to manufacture, available in a wide range, and reliable with predictable performance. However, springs can buckle if deflection exceeds a critical value, and damaged springs are difficult to replace or repair.
Unit 6- Governers , Dynamics of machines of VTU Syllabus prepared by Hareesha N Gowda, Asst. Prof, Dayananda Sagar College of Engg, Blore. Please write to hareeshang@gmail.com for suggestions and criticisms.
This document presents information on a bushed pin type flexible coupling. It begins with an overview of couplings and their purpose in connecting shafts to transfer motion. It then discusses different types of couplings, including rigid and flexible couplings. The main focus is on the design of a bushed pin type flange coupling, including the dimensions and considerations for designing the hub, key, flange, and bolts. Advantages of this type of coupling include being torsionally stiff with good vibration damping, while limitations include sensitivity to chemicals and difficulty in balancing. References used in the presentation are also listed.
This document discusses various types of joints, levers, and beams. It provides details on the design and stress analysis of knuckle joints, hand levers, foot levers, safety valve levers, curved beams with circular cross-sections, and components under eccentric loading. Design considerations include determining shaft diameters, boss dimensions, bending stresses, shear stresses, and torque. Stress analysis methods such as determining the neutral axis location and using superposition of stresses are also outlined.
Unit 5 Design of Threaded and Welded JointsMahesh Shinde
1) The document discusses different types of threaded and welded joints. It describes various threaded fasteners like bolts, studs, screws and their characteristics.
2) For threaded joints subjected to eccentric loads, it explains how to calculate the primary and secondary shear forces on each bolt. This involves finding the center of gravity of the bolt system and determining the forces based on the load direction.
3) Sample problems are included to demonstrate how to select the bolt size based on the maximum resultant shear force and required factor of safety. Calculations are shown for eccentrically loaded bolted joints with the load in the plane of bolts.
Design of steel structure as per is 800(2007)ahsanrabbani
It does not offer resistance against rotation and also termed as a hinged or pinned connections.
It transfers only axial or shear forces and it is not designed for moment
It is generally connected by single bolt/rivet and therefore full rotation is allowed
Unit 2 Design Of Shafts Keys and CouplingsMahesh Shinde
This document provides information about the design of shafts, keys, and couplings. It discusses transmission shafts, stresses induced in shafts, and shaft design based on strength and rigidity. It presents formulas for shaft design using maximum shear stress theory, distortion energy theory, and the ASME code. Several examples are provided to demonstrate how to calculate the diameter of a shaft given the power transmitted, loads on the shaft, material properties, and other parameters using these theories and codes. Assignments involving similar calculations of shaft diameters are presented.
ME010 801 Design of Transmission Elements
(Common with AU010 801)
Teaching scheme Credits: 4
2 hours lecture, 2 hour tutorial and 1 hour drawing per week
Objectives
To provide basic design skill with regard to various transmission elements like clutches, brakes, bearings and
gears.
Module I (20 Hrs)
Clutches - friction clutches- design considerations-multiple disc clutches-cone clutch- centrifugal clutch -
Brakes- Block brake- band brake- band and block brake-internal expanding shoe brake.
Module II (17 Hrs)
Design of bearings - Types - Selection of a bearing type - bearing life - Rolling contact bearings - static
and dynamic load capacity - axial and radial loads - selection of bearings - dynamic equivalent load -
lubrication and lubricants - viscosity - Journal bearings - hydrodynamic theory - design considerations -
heat balance - bearing characteristic number - hydrostatic bearings.
Module III (19 Hrs)
Gears- classification- Gear nomenclature - Tooth profiles - Materials of gears - design of spur, helical,
bevel gears and worm & worm wheel - Law of gearing - virtual or formative number of teeth- gear tooth
failures- Beam strength - Lewis equation- Buckingham’s equation for dynamic load- wear loadendurance strength of tooth- surface durability- heat dissipation - lubrication of gears - Merits and
demerits of each type of gears.
Module IV (16 Hrs)
Design of Internal Combustion Engine parts- Piston, Cylinder, Connecting rod, Flywheel
Design recommendations for Forgings- castings and welded products- rolled sections- turned parts,
screw machined products- Parts produced on milling machines. Design for manufacturing - preparation
of working drawings - working drawings for manufacture of parts with complete specifications including
manufacturing details.
Note: Any one of the following data book is permitted for reference in the final University examination:
1. Machine Design Data hand book by K. Lingaiah, Suma Publishers, Bangalore/ Tata Mc Graw Hill
2. PSG Design Data, DPV Printers, Coimbatore.
Text Books
1. C.S,Sarma, Kamlesh Purohit, Design of Machine Elements Prentice Hall of India Ltd NewDelhi
2. V.B.Bhandari, Design of Machine Elements McGraw Hill Book Company
3. M. F. Spotts, T. E. Shoup, Design of Machine Elements, Pearson Education.
Reference Books
1. J. E. Shigley, Mechanical Engineering Design, McGraw Hill Book Company.
2. Juvinall R.C & Marshek K.M., Fundamentals of Machine Component Design, John Wiley
3. Doughtie V.L., & Vallance A.V., Design of Machine Elements, McGraw Hill Book Company.
4. Siegel, Maleev & Hartman, Mechanical Design of Machines, International Book Company
Design of Flat belt, V belt and chain drivesDr. L K Bhagi
Geometrical relationships, Analysis of belt tensions, Condition for maximum power transmission, Characteristics of belt drives, Selection of flat belt, V- belt, Selection of V belt, Roller chains, Geometrical relationship, Polygonal effect, Power rating of roller chains, Design of chain drive, Introduction to belt drives and belt construction, Introduction to chain drives
This document contains a question bank for the Design of Machine Elements course covering various topics in 5 units. It includes over 180 questions related to steady and variable stresses in machine members, shafts and couplings, joints, energy storing elements, and bearings. The questions cover topics such as stress analysis, materials selection, fits and tolerances, failure theories, stress concentration, fatigue design, and design of common machine components. The document also lists the textbook and references used for the course.
5 shaft shafts subjected to combined twisting moment and bending momentDr.R. SELVAM
1. The document discusses the design of shafts that are subjected to both twisting moments and bending moments.
2. It describes two theories for analyzing combined stresses: maximum shear stress theory for ductile materials like steel, and maximum normal stress theory for brittle materials like cast iron.
3. It provides an example of determining the diameter of a shaft made of 45 C 8 steel that is subjected to a bending moment of 3000 N-m and torque of 10,000 N-m, with a safety factor of 6.
This document discusses belt, rope, and chain drives used to transmit power between rotating shafts. It describes factors that affect the amount of power transmitted by belts, such as velocity, tension, and arc of contact. It also outlines conditions for proper belt use, types of belt drives based on power level, and sources of belt slippage. Additionally, it provides details on chain drives, including types of chains, construction, geometry considerations for sprockets and chain length, and recommended angle of contact.
The document discusses stresses in flywheel components and design considerations. It describes:
1. A flywheel consists of a rim to concentrate mass, a hub to attach to a shaft, and arms to support the rim.
2. Stresses induced in the rim include tensile stress from centrifugal force, tensile bending stress from arm restraint, and shrinkage stresses from uneven cooling.
3. The tensile stress in the rim from centrifugal force is calculated similarly to a thin cylinder under pressure. Stresses in the arms include tensile stress from centrifugal force and bending stress from transmitting torque.
Springs are elastic machine elements that deflect under load and return to their original shape when the load is removed. This document discusses the design of helical compression springs. It defines spring terminology such as mean diameter, spring index, solid length, and pitch. It presents the load-stress and load-deflection equations for spring design. It also discusses stresses in springs, series and parallel spring connections, surge, and the design procedure for helical springs. As an example, it solves a problem involving the design of concentric springs for an aircraft engine valve.
Spring is an elastic body whose function is to distort when loaded and to recover its original shape when the load is removed.
APPLICATION OF SPRINGS
To apply forces as in brakes, clutches and spring loaded valves.
To store energy as in watches, toys.
To measure forces as in spring balance and engine indicators.
To cushion, absorb or control energy due to either shock or vibration as in car.The material of the spring should have
high fatigue strength,
high ductility,
high resilience and
creep resistant.
It largely depends upon the size and service.
The strength of the wires varies with size, smaller size wires have greater strength and less ductility, due to the greater degree of cold working.
Severe service means rapid continuous loading where the ratio of minimum to maximum load (or stress) is one-half or less, as in automotive valve springs.
Average service includes the same stress range as in severe service but with only intermittent operation, as in engine governor springs and automobile suspension springs.
Light service includes springs subjected to loads that are static or very infrequently varied, as in safety valve springs.
The springs are mostly made from oil-tempered carbon steel wires containing 0.60 to 0.70 per cent carbon and 0.60 to 1.0 per cent manganese.
Springs are elastic bodies that store mechanical energy when compressed, stretched, or twisted by an external force. Common materials used for springs include various types of steel, copper alloys, and titanium. Springs can be arranged in series or parallel configurations, and the total spring constant of combined systems can be calculated. Different types of springs include helical, leaf, and disc springs, which are used for various purposes like absorbing shock, storing energy, and maintaining contact forces. Helical springs specifically can be tensional, compression, torsion, or spiral types.
Lecture 13 torsion in solid and hollow shafts 1Deepak Agarwal
The document discusses stresses in beams and shafts subjected to torsion. It covers torsional deformation of circular shafts, shear stresses and strains from torques, polar moment of inertia, torsional rigidity, and stresses in shafts under combined bending and torsion loads. Key formulas are presented relating torque to shear stress, polar modulus, bending stress, and principal stresses under combined loading. Applications to solid and hollow circular shafts and bars subjected to forces, bending moments, shear forces, and torques are described.
The document discusses gears and their classification. It defines various gear types including spur gears, helical gears, bevel gears, worm gears, and rack gears. It covers gear terminology such as pressure angle and describes how parameters like pressure angle and center distance affect gear performance and interference. Methods to avoid interference include increasing center distance, tooth modification, and changing the number of teeth. Backlash is also defined as the clearance between mating gear teeth.
Design and Analysis of Flange CouplingIJERA Editor
The approach utilizes standard design equations of these couplings and links them together in computer software to determine the design parameters of the couplings. In general, most flange coupling is available in transformation system and automobile industries. A flange coupling usually applies to a coupling having two cast iron flanges. To achieve a require goal, a design of bolted unprotected flange coupling is modeled in to a cad package named Solid works. Furthered the finite element analysis module is created in ANSYS Workbench by using ANSYS Static Structural module which has a predefined process to obtain optimum results.
spring, types, working and advantages and disadvantages.sannanshafiq
Springs are elastic bodies that distort under load and recover their original shape when unloaded. The major types of springs are helical, conical, torsion, laminated/leaf, and disc springs. Springs work based on Hooke's law, where the force is directly proportional to displacement from the original position. Springs have advantages of being easy to manufacture, available in a wide range, and reliable with predictable performance. However, springs can buckle if deflection exceeds a critical value, and damaged springs are difficult to replace or repair.
Unit 6- Governers , Dynamics of machines of VTU Syllabus prepared by Hareesha N Gowda, Asst. Prof, Dayananda Sagar College of Engg, Blore. Please write to hareeshang@gmail.com for suggestions and criticisms.
This document presents information on a bushed pin type flexible coupling. It begins with an overview of couplings and their purpose in connecting shafts to transfer motion. It then discusses different types of couplings, including rigid and flexible couplings. The main focus is on the design of a bushed pin type flange coupling, including the dimensions and considerations for designing the hub, key, flange, and bolts. Advantages of this type of coupling include being torsionally stiff with good vibration damping, while limitations include sensitivity to chemicals and difficulty in balancing. References used in the presentation are also listed.
This document discusses various types of joints, levers, and beams. It provides details on the design and stress analysis of knuckle joints, hand levers, foot levers, safety valve levers, curved beams with circular cross-sections, and components under eccentric loading. Design considerations include determining shaft diameters, boss dimensions, bending stresses, shear stresses, and torque. Stress analysis methods such as determining the neutral axis location and using superposition of stresses are also outlined.
Unit 5 Design of Threaded and Welded JointsMahesh Shinde
1) The document discusses different types of threaded and welded joints. It describes various threaded fasteners like bolts, studs, screws and their characteristics.
2) For threaded joints subjected to eccentric loads, it explains how to calculate the primary and secondary shear forces on each bolt. This involves finding the center of gravity of the bolt system and determining the forces based on the load direction.
3) Sample problems are included to demonstrate how to select the bolt size based on the maximum resultant shear force and required factor of safety. Calculations are shown for eccentrically loaded bolted joints with the load in the plane of bolts.
Design of steel structure as per is 800(2007)ahsanrabbani
It does not offer resistance against rotation and also termed as a hinged or pinned connections.
It transfers only axial or shear forces and it is not designed for moment
It is generally connected by single bolt/rivet and therefore full rotation is allowed
Threaded fasteners such as bolts and nuts are used to join machine parts. They allow parts to be dismantled without damage. Threaded joints provide clamping force through wedge action of threads. They are reliable, have small dimensions, and can be positioned vertically, horizontally, or inclined. However, they require holes which cause stress concentrations and can loosen under vibration. Bolts have heads and threaded shanks, while nuts have internal threads. Washers distribute load and prevent marring. Bolts are subjected to both tension and shear stresses, and standard nuts have a height of 0.8 times the bolt diameter to prevent shear failure. Eccentric loads on bolts cause additional stresses.
The document discusses the design of power screws. Power screws convert rotary motion into linear motion and are used in applications like lathes, screw jacks, presses, and vices. There are several types of thread profiles used in power screws including square, acme, trapezoidal, and buttress threads. Square threads provide maximum efficiency but are weaker. Acme threads are stronger and allow for split nuts. The document provides formulas to calculate the torque required to raise or lower a load using a power screw based on factors like thread angle, friction angle, and load weight. It also discusses design considerations for parts of a screw jack like the screw, nut, nut collar, screw head, and handle.
A kinematic pair with one degree of freedom called a screw joint is utilised in mechanisms. In screw joints, single-axis translation is accomplished by using the lead screw's threads as the translation medium. The majority of linear actuator types and some kinds of cartesian robots employ this kind of joint.
The document discusses various topics related to screwed joints and fastenings including:
1. The advantages and disadvantages of screwed joints.
2. Important terms used in screw threads such as major diameter, pitch, and crest.
3. Different types of screw threads including British Standard, American, and metric threads.
4. Factors to consider when locating screwed joints such as reducing bending stresses.
5. Common types of screw fastenings like through bolts, studs, and set screws.
Threaded fasteners such as bolts and screws join components together through the transformation of rotational motion into linear motion. There are various thread standards that specify attributes like diameter, pitch, class of fit, and thread type. Early threaded fasteners lacked standardization but efforts in the 18th-19th centuries established conventions for sizes. Modern standards include metric and unified external and internal thread systems.
This document describes different types of cotter and knuckle joints used to connect rods transmitting axial motion. Cotter joints use a wedge-shaped cotter to rigidly connect two rods without rotation. Sleeve and cotter joints use an enlarged sleeve over rod ends. Socket and spigot cotter joints have slots wider than the cotter to pull rods tightly together. Gib and cotter joints add a gib to prevent strap spreading. Knuckle joints connect misaligned rods allowing small angular motion. Applications include steam engines, pumps, valves and elevators. The document also provides design considerations and failure modes for socket and spigot cotter joints.
1) Connections are an important part of steel structures as they allow different structural elements to act together as a single unit by transferring forces between members. Common types of connections include riveted, bolted, welded, and pinned connections.
2) Bolted connections use bolts with heads and threaded ends to connect structural elements. Steel washers are often included to distribute clamping pressure and prevent bearing on connected pieces.
3) Design of bolted connections considers factors like bolt grade, type of joint, edge and end distances, pitch, and capacity in shear, tension, and bearing to ensure the connection can safely transfer loads between members. Failure can occur in bolts or connected elements due to various limit
The document discusses the design of machine elements. It covers factors governing design, general design procedures, stresses in bolts, nuts and keys, and design of cylinder cover bolts. Key points covered include:
1) The factors governing machine element design include strength, cost, reliability, shape, size, friction, corrosion and more.
2) General design procedures include identifying needs, analyzing forces, selecting materials, determining sizes, and producing detailed drawings.
3) Stresses in bolted connections from initial tightening, external loads, and combined loads are analyzed. Formulas to calculate bolt sizes based on allowable stresses are presented.
4) The design of cylinder cover bolts involves calculating the pitch
The document discusses different aspects of screw thread metrology. It describes the key elements of a screw thread such as major diameter, minor diameter, pitch diameter, pitch, lead, crest, root, depth of thread, flank, and angle of thread. It then discusses different forms of screw threads including British Standard Whitworth, British Association, American National Standard, Unified Standard, square, Acme, knuckle, and buttress threads. The final sections cover various methods for measuring elements of a screw thread such as major diameter, minor diameter, pitch diameter, pitch, and thread angle using instruments like micrometers, thread micrometers, pitch measuring machines, and tool makers microscopes.
The document discusses various types of shafts and shaft couplings. It provides information on shaft materials, sizing, layout and design considerations. Regarding couplings, it describes rigid couplings like sleeve, flange and marine couplings. It also discusses flexible bush pin couplings. Key points covered include shaft material selection, stress analysis for sizing, deflection requirements, coupling design for strength, rigidity and alignment between connected shafts. Common shaft and coupling types, their designs and applications are explained.
Unit 4 Design of Power Screw and Screw JackMahesh Shinde
The document discusses power screws, including their terminology, types of threads, torque analysis, and efficiency. It defines key terms like nominal diameter, pitch, lead, and lead angle. It describes common types of threads like square, ACME, and buttress threads. It discusses torque required to raise and lower loads, including expressions for self-locking and overhauling screws. The document also covers screw efficiency and collar friction torque, providing expressions to calculate overall efficiency. An example calculation is given to find maximum load lifted, efficiency, and overall efficiency of a screw jack.
The document discusses different types of fasteners used to join machine parts, including screwed fasteners, riveted joints, and keys. It describes various threaded components like bolts, nuts, and studs. It discusses different thread profiles like metric, square, and ACME threads. It also covers rivet types, dimensions of riveted joints, and types of keys used in pin joints.
Couplings are used to connect two rotating shafts and transmit torque from one to the other. There are two main types of couplings: rigid couplings for perfectly aligned shafts, and flexible couplings for shafts with misalignment which absorb shocks and vibrations. Common rigid couplings include sleeve, flange, and split-muff couplings which connect shafts through a sleeve or bolted flanges. Flexible bush pin couplings connect shafts through pins with rubber bushes to absorb shocks and compensate for misalignment.
This document discusses mechanical fasteners. It defines fasteners as mechanical elements that hold two or more machine or structural parts together. Fasteners are classified as detachable or non-detachable. Threaded and non-threaded fasteners are types of detachable fasteners. Common threaded fasteners include bolts, screws, and nuts. The document provides details on threaded fastener terminology, types of threads, thread manufacturing, and considerations for selecting an appropriate fastener.
This document summarizes key aspects of screw thread design and manufacturing. It defines screw threads as helical ridges on cylinders used for bolts, nuts, and tapped holes. Thread forms have crests, roots, and flanks that make up the thread profile. Pitch is the distance between threads, measured parallel to the axis. Thread tolerances and allowances determine the fit between external and internal threads. Threads can be cut or rolled, with rolling producing stronger threads by compressing material into the roots. Proper thread design ensures bolts break in tension before threads strip.
This document discusses riveted joints and provides information on:
1. Types of riveted joints include lap joints and butt joints. A lap joint has one plate overlapping the other, while a butt joint has plates aligned and touching with a cover plate riveted on one or both sides.
2. Important terms for riveted joints include pitch (distance between rivet centers), transverse pitch, diagonal pitch, and margin (distance from rivet hole to plate edge).
3. Dimensions for riveted joints include rivet diameter, hole diameter 1.5 times rivet diameter, longitudinal pitch 3 times rivet diameter, and transverse/zigzag pitch as a ratio of longitudinal pitch.
Tools & Techniques for Commissioning and Maintaining PV Systems W-Animations ...Transcat
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Sri Guru Hargobind Ji - Bandi Chor Guru.pdfBalvir Singh
Sri Guru Hargobind Ji (19 June 1595 - 3 March 1644) is revered as the Sixth Nanak.
• On 25 May 1606 Guru Arjan nominated his son Sri Hargobind Ji as his successor. Shortly
afterwards, Guru Arjan was arrested, tortured and killed by order of the Mogul Emperor
Jahangir.
• Guru Hargobind's succession ceremony took place on 24 June 1606. He was barely
eleven years old when he became 6th Guru.
• As ordered by Guru Arjan Dev Ji, he put on two swords, one indicated his spiritual
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• He had a long tenure as Guru, lasting 37 years, 9 months and 3 days
Better Builder Magazine brings together premium product manufactures and leading builders to create better differentiated homes and buildings that use less energy, save water and reduce our impact on the environment. The magazine is published four times a year.
Sachpazis_Consolidation Settlement Calculation Program-The Python Code and th...Dr.Costas Sachpazis
Consolidation Settlement Calculation Program-The Python Code
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Impartiality as per ISO /IEC 17025:2017 StandardMuhammadJazib15
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We have designed & manufacture the Lubi Valves LBF series type of Butterfly Valves for General Utility Water applications as well as for HVAC applications.
3. Introduction
• A screw thread is formed by cutting a
continuous helical groove on cylindrical
surface.
• A continuous single helical groove is known as
single threaded or single start.
• If second groove is cut into the space between
the groove of first then it is double threaded or
double start.
• Screw joint are formed by bolt and nut used
for joining machine parts or for fastening,
adjustment, assembly, inspection, replacement.
4. • Advantages –
1) These are convenient to assemble and
disassemble.
2) Highly reliable in operation.
3) Screw joint are adopted in various operating
conditions.
4) Screws are relatively cheap to produce due to
standardization.
Disadvantages –
The main disadvantage of this joint is the
stress concentration in the thread portion and
strength is less than welded or riveted joint.
5. Types of Screw fastening
Types of Screw
Fastening
1. Bolts
(i) Through Bolt
(ii) Tap Bolts
2. Cap Screw
3. Stud
4. Machine Screw
5. Set Screw
6. Types of Screw Fastening
• Bolts - They are basically threaded fasteners
normally used with nuts.
• Screws - They engage either with a preformed or
a self made internal threads.
• Studs -They are externally threaded headless
fasteners. One end usually meets a tapped
component and the other with a standard nut.
• Tapping screws -These are one piece fasteners
which cut or form a mating thread when driven
into a preformed hole. These allow rapid
installation since nuts are not used.
• Set Screws -These are semi permanent fasteners
which hold collars, pulleys, gears etc on a shaft.
Different heads and point styles are available.
7. • Examples where screw joints are preferred
over welded joint.
1) Assembly of crank shaft and connecting rod.
2) In braking system of an automobile because
screw joints are convenient to assemble and
disassemble and relatively cheap to produce
due to standardization.
8. Advantages of V thread
1) V threads offers greater frictional resistance
of motion than square thread and are thus
better suited for fastening purpose.
2) These are stronger than square thread.
3) These are cheaper because of easy to cut by
die or on machine.
4) These are used to tighten the parts together in
bolts, nuts, stud and nut, tap bolts etc. because
they prevent the nut from slacking back due
to high frictional resistance.
9. Disadvantages
1) V threads are not suitable for power
transmission.
2) They have a component of force which acts
perpendicular to the axis causing bursting
action on the nut and increasing friction.
13. 1. Major diameter (do)-
• It is the largest diameter of an external or
internal screw thread.
• The screw is specified by this diameter. It is also
known as outside or nominal diameter.
2. Minor diameter (dc)-
• It is the smallest diameter of an external or
internal screw thread.
• It is also known as core or root diameter.
14. 3. Pitch diameter (dp) –
• It is the diameter of an imaginary cylinder, on a
cylindrical screw thread, the surface of which
would pass through the thread at such points as to
make equal the width of the thread and the width
of the spaces between the threads.
• It is also called an effective diameter.
4. Pitch (p) -
• It is the distance from a point on one thread to the
corresponding point on the next.
• This is measured in an axial direction between
corresponding points in the same axial plane.
15. 5. Lead -
• It is the distance between two corresponding
points on the same helix.
• It may also be defined as the distance which a
screw thread advances axially in one rotation of
the nut.
• Lead is equal to the pitch in case of single start
threads, it is twice the pitch in double start, thrice
the pitch in triple start and so on.
6. Crest - It is the top surface of the thread.
16. 7. Root - It is the bottom surface created by the two
adjacent flanks of the thread.
8. Depth of thread - It is the perpendicular
distance between the crest and root.
9. Flank - It is the surface joining the crest and
root.
10. Angle of thread - It is the angle included by
the flanks of the thread.
11. Slope - It is half the pitch of the thread.
17. Stresses in screw fastenings
• It is necessary to determine the
stresses in screw fastening due to
both static and dynamic loading in
order to determine their dimensions.
In order to design for static loading
both initial tightening and external
loadings need be known.
18. A) Initial tightening load
When a nut is tightened over a screw following
stresses are induced:
(a) Tensile stresses due to stretching of the bolt
(b) Torsional shear stress due to frictional
resistance at the threads.
(c) Shear stress across threads
(d) Compressive or crushing stress on the threads
(e) Bending stress if the surfaces under the bolt
head or nut are not perfectly normal to the bolt
axis.
19. a) Tensile Stress –
Since none of the above mentioned stresses
can be accurately determined bolts are usually
designed on the basis of direct tensile stress
with a large factor of safety.
bolts
in
tension
Initial
P
d
diameter
Core
d
screw
of
pitch
or
diameter
Mean
d
Where
d
d
d
A
P
i
o
c
c
o
i
t
84
.
0
)
2
(
4
2840
2
20. b) Torsional shear stress -
Due to twisting moment, the bolt is subjected to
torsional shear stress.
torque
Twisting
T
inertia
of
moment
Polar
I
Where
d
T
d
T
d
d
T
r
I
T
l
G
r
I
T
P
c
s
c
c
c
s
P
s
s
P
3
3
3
16
16
2
32
22. d) Crushing stress on threads
The compression or crushing stress between the
thread of screw nut is given by
n
d
d
P
c
o
cr
c
)
( 2
2
23. e) Bending Stress
Let, X – difference in height between the extreme
corner of the nut or head.
E – Modulus of elasticity
l – length of shank of the bolt
The bending stress induced in the shank of the bolt is
given by
l
XE
b
2
24. 2. Stresses due to external forces
a) Tensile stress –
c
o
c
t
c
c
t
d
d
n
d
P
then
bolts
of
number
the
is
n
if
out
found
is
d
d
P
84
.
0
4
4
2
2
25. b) Shear Stress in bolt –
n
d
P
o
s
2
4
c) Combine tension and shear stress
]
4
[
2
1
]
4
[
2
1
)
(
2
2
max
2
2
max
t
t
t
t
stress
shear
Maximum
sress
tensile
principal
Maximum
26. 3. Stress due to combine forces
• The resultant load on the bolt is
bolt
of
elsicity
the
to
parts
connected
of
elasticity
of
Ratio
a
bolts
the
on
load
Extrnal
P
bolts
of
tightening
to
due
tension
Initial
P
a
a
k
Where
kP
P
P
P
a
a
P
P
i
i
i
2
2
2
)
1
(
)
1
(
28. Bolts with Uniform strength
• When a bolt is subjected to shock load. the In such
cases the bolt is designed to absorb impact load and
to resist the torque to prevent breakage of thread.
• In ordinary bolts, the effect of load concentration
on the weakest part of the bolt i.e. The c/s area of
the root of the thread.
• The stress in the threaded part will be more as
compared to the shank hence the maximum portion
of energy will be absorbed at the region of the
threaded part which may fracture the threaded
portion.
29.
30. • If the diameter of shank of the bolt is turned to
the core diameter of the thread, then the shank
of the bolt will undergo a higher stress. This
means that shank will absorb large portion of
energy thus relieving the material at the
threaded portion.
• The bolt in this way become stronger and
lighter and it increases the impact load
carrying capacity. This gives us bolts of
uniform strength.
31. • Another method, an axial hole is drilled
through the head of the bolt as far as threaded
portion, such area of the shank become equal
to the root area of the thread.
thread
of
diameter
core
d
thread
of
diameter
outer
d
hole
of
diameter
D
where
d
d
D
d
d
D
c
o
c
o
c
o
,
)
(
)
(
4
4
2
2
2
2
2
32. Design of bolted joint subjected to
Eccentric Loading
• There are many application of the bolted joints
which are subjected to eccentric loading such as
machine foundation bolt, wall brackets, pillar
crane, etc.
1) Parallel to the axis of bolts.
2) Perpendicular to the axis of bolts.
3) In the plane containing the bolts.
34. a) Each bolt is subjected to direct tensile load.
b) Due to load W the bracket tends to rotate
about edge A-A
Let w – load in a bolt per unit distance due to
turning effect of the bracket
bolts
of
Number
n
bracket
on
acting
load
W
load
tensile
Direct
W
n
W
W
td
td
35. • W1 & W2 – load on bolt at a distance L1 & L2
from tilting edge.
Load on each bolt at distance L1
W1 = w L1
Similarly, load on each bolt at distance L2
W2 = w L2
The moment of load W1 about tilting edge
2
1
1
1
1
1
1 wL
L
wL
L
W
M
36. • Similarly, the moment of load W2 about tilting
edge
)
2
(
,
tan
)
1
(
]
[
2 2
2
2
1
2
1
2
2
2
2
2
2
2
WL
M
edge
tilting
about
L
ce
dis
a
at
W
load
the
of
moment
The
wL
wL
M
M
M
edge
tilting
about
load
of
moment
Total
wL
L
wL
L
W
M
Equating equation (1) and (2)
40. 2. The eccentric load (W) will try to tilt the bracket
in clockwise direction about the tilting edge B-B.
Therefore maximum tensile load will be act on bolt
at position 3 and 4 which are at a greater distance
from the tilting edge.
Let, w = load in the bolt per unit distance due to
turning effect of the bracket.
Wt= Tensile load each bolt at a distance L1 from the
tilting edge B-B.
42. • Similarly Wt will be the tensile load each bolt at
a distance L2 from the tilting edge B-B.
)
5
(
]
[
2
2
2
)
4
(
2
,
.
2
2
2
1
2
2
2
1
2
1
2
2
2
2
2
2
2
2
2
2
2
2
L
L
w
M
L
w
L
w
M
M
M
M
is
edge
tilting
about
moment
Total
L
w
M
hence
L
dist
a
at
are
bolts
two
the
As
L
w
L
W
M
edge
tilting
about
W
load
the
of
Moment
L
w
W
t
t
t
47. • In this case, the bolts are subjected to two types
of load –
1. The Direct shear load (Wsd) –
Wsd = (W/n) ----- (a)
2. The secondary shear load (Ws2)
a) This secondary load is perpendicular to line
joining the centre of the bolt.
b) This secondary load is perpendicular to the
radial distance.
50. • Sum of turning moment due to eccentric load and
internal resisting moment of the bolt must be
zero.
calculated
is
W
b
equation
From
b
l
l
l
l
l
W
l
l
l
W
l
l
l
W
l
l
l
W
l
W
l
W
l
W
l
W
l
W
e
W
1
2
4
2
3
2
2
2
1
1
1
4
1
4
1
3
1
3
1
2
1
2
1
1
1
4
4
3
3
2
2
1
1
'
'
)
(
]
[
)
(
)
(
)
(
54. Welded Joints
• Welding is a process of joining
two similar metal by heating
with or without application of
pressure and filler materials.
• Welded joint can be used an
alternatively to riveted joint.
55. Advantages
1) The welded structure are usually lighter than
riveted structure because in welding, gussets and
other connecting component are not used.
2) Weld joint provide maximum efficiency which is
not possible by riveted joint.
3) Alteration and addition can be easily made in the
exiting structure.
4) It is smooth in appearance therefore looks
pleasing.
5) In welded connection, the tension member are
not weakened as in case of riveted joint.
56. 6) A weld joint has greater strength often a
welded joint has the strength of the parent
metal itself.
7) Circular shape member are difficult to rivet
but they can easily welded.
8) The welding provide very rigid joints
9) Welding is possible at any point, any place.
10) Welding required less time than the riveting.
57. Disadvantages
1) Due to uneven heating and cooling during
fabrication, the members get distorted or
addition stresses may developed.
2) Highly skilled worker and supervision is
required.
3) Due to uneven contraction and expansion in
the frame, there is possibilities of cracks.
4) The inspection of weld is difficult than
riveted joint.
58. Types of welded joint
1) Lap Joint:
The Lap Joint is obtained by over lapping the
plates and then welding the edge of plates.
a) Single transverse
b) Double transverse
c) Parallel fillet joints.
59.
60. 2) Butt Joints:
The butt joint is obtained by welding the ends
and edge of the two plates which approximately
in the same plane.
The Butt Joint may
1. Square butt joint,
2. Single V-butt joint
3. Single U-butt joint,
4. Double V-butt joint, and
5. Double U-butt joint.
65. • In order to determine the strength of the fillet joint, it is
assumed that the section of fillet is a right angled
triangle ABC with hypotenuse AC making equal angles
with other two sides AB and BC.
• The enlarged view of the fillet is shown in Fig. 10.7.
• The length of each side is known as leg or size of the
weld and the perpendicular distance of the hypotenuse
from the intersection of legs (i.e. BD) is known as
throat thickness.
• The minimum area of the weld is obtained at the
throat BD, which is given by the product of the throat
thickness and length of weld.
72. • In combination of parallel and transverse fillet
weld, the weld is subjected to tensile stress and
shear stress due to axial force.
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73. • Note –
1. Stress concentration factor for transverse
fillet weld Under dynamic (fatigue)
loading = 1.5
2. Stress concentration factor for parallel
fillet weld Under dynamic (fatigue)
loading = 2.7