Percentage saving in weight of hollow shaft vs solid shaft. Jun 07, 2018 difference between hollow shaft and solid shaft is one of the important comparisons in design of machine elements. Maximum shear stress of 80 mpa is applied on the shaft. If the hollow shaft of aluminum is used, slide two steel inserts into the ends where the. May 25, 2018 in this video i give step by step procedure how we compare solid shaft and hollow shaft in terms of weight, strength and rigidity.
The fraunhofer iwu has become a leader in the production of rotary parts by forming. I recall being told once that hollow rodsshafts tend to resist torsion more than solid rodsshafts. The drilling crew can take samples through the hollow stem, or use it for setting a. Hollow circular shaft with outer diameter d 2 and wall thickness of 10% d 2. The shear stress developed in a hollow shaft is lesser than that developed in a stable shaft for a similar utilized torque and same exterior diameter. The shfcr1 series is a highperformance, zero tooth backlash gearhead that integrates a cross roller output bearing and features a hollow input shaft.
Test procedure for solid and hollow ductile shafts. I vaguely understood the ideas expressed in the answers there still trying to wrap my head around the second moment of. Crosssections of noncircular nonaxisymmetric shafts are distorted when subjected to torsion. If speed feedback is a crucial factor, a hollow shaft encoder is the best choice. The only feature left with the solid shaft is its diameter you dont need to mention outer diameter, if its a solid shaft. A hollow shaft has greater strength and stiffness than a. Hollowshaft construction is available in frame sizes 2 and larger whereas solidshaft construction is available in 182 and larger. Shaft subjected to bending moment only linkedin slideshare.
Comparative study of hollow and solid shaft for the application in. Besides standard versions, eltra offers to its customers the. Solid and hollow shaft when the shaft is subjected to combined twisting moment ad bending moment then the shaft must be designed on the basic of two moments simultaneously. Crosssections for hollow and solid circular shafts remain plain and undistorted because a circular shaft is axisymmetric. A solid shaft in bending or tensile or compressive forces will always be significantly stronger for the same material, dimensions and loading. Shafts hollow shafts misumi misumi south east asia. Comparison between solid and hollow shafts, in this tutorial you will learn about comparison between solid and hollow shafts.
Our motors are high efficiency, high starting torque, quiet running, with low vibration and low temperature rise. Hollow shaft construction is available in frame sizes 2 and larger whereas solid shaft construction is available in 182 and larger. Both hollowshaft and solidshaft motors are described in this instruction book. In general, this analysis allow us to determine the social, technological, economic. Hollow shafts do not transfer more power but the power to weight ratio of hollow shafts is more as compared to a solid shaft. Hollow shaft is having a through hole which is concentric with the external diameter of the shaft. The design of the main shaft of a small wind turbine capstone.
While, a solid shaft doesnt contain any through concentric hole inside it. Novotechnik hollow shaft angle sensors offer high quality construction, precision and accept various shaft sizes and configurations. Me 457 experimental solid mechanics lab torsion test. Hollow shaft solid shaft speed changers and reducers miki. A hollow shaft has greater strength and stiffness than a solid shaft of equal weight. What is the minimum diameter, d, of the solid shaft. If the area of cross section of both the hollow and the solid shaft is same along with power transmission in solid and hollow shaftread more. Eltra has developed a broad catalog of incremental encoders here classified according to the type of mechanical mounting solid vs blindthough hollow shaft and the type of sensing technology optical vs magnetic, with a wide range of resolution, flange and electronic outputs available to meet the specific applications needs. Measure the diameter of the test specimen using the caliper take an average of 5 measurements. Hollow shafting is stronger as a cantilevered application than a simply supported each hollow shaft. Which shaft design will be more weight efficient and why.
Vertical hollow shaft motors are designed primarily for deep well turbine pump applications. They use hollowshaft speed reducers and do not require transmission components such as couplings, chains, or sprockets, so virtually nothing rotating is exposed to the outside, and high safety is assured without use of a safety cover. Hollow shafts are having a more polar moment of inertia, thus they can transmit more torque compared to solid shafts. The shaft extension on these motors normally has an annular ringshaped keyway to carry the thrust of the pump and a radial keyway to transmit torque.
To prove this we have to compare the shaft bending stress developed for the same applied bending moment to the hollow shaft and solid shaft. Harmonic gearing with integrated cross roller bearing. Direct drive and hollow shaft motors harmonic drive. Torsional rigidity is defined as the torque required to produce a twist of one radian per unit length of. The electromechanical device in the optical rotary encoder is designed to register changes in relation to a reference position and detects angle, distance travelled, speed. The electromechanical device in the optical rotary encoder is designed to register changes in relation to a reference position and detects angle, distance travelled, speed, acceleration or direction of rotation. We will use the beam bending equation here for the calculation of bending moment stress. This type coupling is more common on shallow pumps and tanks than on deepwell applications. If you see the shear stress diagram of a shaft on application of torque it would. Shaft deformations when subjected to torsion, every cross section of a circular shaft remains plane and undistorted. A hollow shaft made of nodular cast iron is used to transmit torque within an automatic transmission. But if we have radial space constraint then solid shaft is preferred since, in this case solid shaft has more power transfer capacity than hollow shaft. Incremental encoder incremental encoder with solid shaft or.
There are two kinds of shafts that a vertical pump motor typically has. Very similar to most direct driven horizontal motors. Incremental encoder incremental encoder with solid shaft. Once the bore hole reaches the desired depth, the hollow stem acts as a temporary casing, keeping the sides of the bore hole from caving in. Before we start this case, have a look at these manipulations. A hollow shaft encoder mount is one of the lowestoverhead, loweststress options. Since both are the same materials and all im trying to do is duplicate the amount of torque and stresses that the solid shaft is able to handle what formulas andor thumbrules would you consider best for using, thanks. Before looking into the difference, let us know what is a shaft. In general, a hollow shaft is stronger than a solid shaft for the same specific weight. As shown in the figure, shear stress in a shaft subjected to torsion varies linearly from zero at the center to the maximum at the boundary. In this case maximum stresses induced in the shaft is determined by the theory of simple bending. Some shafts, for example true temper sensicore, have a straw like insert inside for vibration absorbent purposes.
Rdrive vertical hollow shaft motors, other mounts and. A shaft for torque transmission like crank shafts, drive shafts it is always better to choose a solid shaft because it has higher torsional stiffness. Shafts hollow shafts misumi features this shaft facilitates customers to arrange wiring, because the wire can be pierced into the inside of the shaft and contributes to weight saving of equipment, because the shaft is hollow. Slide the shaft into the troptometer and tighten down the two fastening screws to the shaft. Incremental rotary encoders our products incremental rotary encoders are used in virtually all branches of industry for the acquisition of measured data for rotary movements.
Kdu the kdu series are direct drive motors which achieve 10 arcsec positioning accuracy as well as 0. The bending stress fs developed in a solid shaft is given by. Incremental rotary encoders are used in virtually all branches of industry for the acquisition of measured data for rotary movements. Here are the key difference between hollow shaft and solid shaft. The geometric dimensions of the notched shaft are shown in figure 4. Gear tooth forming by means of gear tooth rolling and the manufacturing of the hollow shafts by means of spin extrusion are two technologies that have been engineered and can be employed to optimise production engineering process in terms of resource efficiency. The standard is a solid shaft which is comparable to most other motor shafts and couple to the pumps shaft with a keyed coupling. A hollow rod that weighs the same as a solid rod will be much wider so the force will be spread over a much larger area. Large hollow shaft design allows cables, shafts or lasers to pass through the axis of rotation. The shaft of this screw conveyor had a weak spot with a hole at one location, caused by scouring. I need to determine the dimensions of the hollow shaft if the maximum stress is to be the same as for the solid shaft. What is the difference between a hollow shaft and a solid.
Also evaluate the torque considering the hollow shaft of 100 mm inner diameter. The stress distribution in the case of the solid shaft is zero at the center and maximum at the outer. Both hollow shaft and solid shaft motors are described in this instruction book. Difference between hollow shaft and solid shaft mechopedia. A solid shaft in bending or tensile or compressive forces will always be significantly stronger for the same material,dimensions and loading. Dec 23, 2016 shaft subjected to bending moment only 1. The capability to weight ratio in hollow shaft is greater than the solid shaft. Power transmission in solid and hollow shaft exergic. Figures 46 show typical hollowshaft high thrust motors and figures 7. Hollow shaft gearboxes and gearheads engineering360. Rwm models these are hollow shaft geared motors for motor outputs of 0.
Dec 17, 2011 solid shaft models couple to the pump shaft at the lower end of the motor. Hollow shaft is not always better compare to a solid shaft. Hollow shafts are much better to take torsional loads compared to solid shafts. Pumps with vertical hollow shaft actuators are used at wastewater discharge and water supply facilities, as well as in pulp and paper production, well drilling, agriculture, and mining. Why is a hollow tube more stable than a solid tube. It generally has circular crosssection and can be solid or hollow. The diameter of the hollow shaft is more than the solid shaft and require more space. Mar 09, 2017 comparison between solid and hollow shafts, in this tutorial you will learn about comparison between solid and hollow shafts. I also need to know what the percentage saving in weight of the hollow shaft compared with the solid one. This design offers simplicity because a hollow shaft encoder is compact, adjustable, and versatile. The shaft was repaired by welding around the weak spot with the hole.
So hollow shaft is better than solid shaft in terms of the cost. Com 2031 american ave hayward, california 94545 telephone. When there is no space constraint, then for same mass, hollow shaft is better than solid shaft. Shafts are supported on the bearings and transmit torque with the help of gears, belts and pulleys etc. The only feature left with the solid shaft is its diameter you dont n. Comparison of hollow and solid shaft by strength youtube. Shaft and coupling basic interview question and answers strength of material som notes free pdf download coupling design requirement, types, design of sleeve coupling what is drive shaft, driveshaft, driving shaft, propeller shaft hollow shaft vs solid shaft which is better. Shafts are generally subjected to bending moment, torsion and axial force or a. A hollow shaft vertical motor works a bit differently. Diameter of a solid shaft can calculated by the formula. To reduce the cost, the manufacturers prefer the hollow shaft rather than the solid shaft.
Shaft is a common machine element which is used to transmit rotary motion or torque. Any rotating member which is transmitting torque is called shaft. Difference between hollow shaft and solid shaft is one of the important comparisons in design of machine elements. Figures 46 show typical hollow shaft high thrust motors and figures 79 show typical solid shaft high. For a shaft transmitting power po at a rotational speed n, the transmitted torque t can be found from t nm 9550 po kw n rpm or. Hollow shaft harmonic gearhead shcr1 series from conic systems. Shaft subjected to bending moment only when the shaft is subjected to pure bending load, the principle stresses induced in the shaft are tension and compression.
Bending strength in this case is proportional to the moment of inertia which for a constant mass is higher if the mass is distributed further away from the center. Rwm models these are hollowshaft geared motors for motor outputs of 0. Aurora motors provide long and troublefree service under challenging conditions with minimum maintenance requirements. Solid is stronger in the simply supported on both ends application. Horizontal motors, or parallel drives, are preferred in generalpurpose applications where external thrust affecting the bearing is either zero or close to the. Calculate the torque that can be applied on the shaft for the given shear stress. Sep 08, 2011 lecture torsion in solid and hollow shafts 1 1. This kind of drilling is like solid stem, except the claw bit is attached to a hollow stem, instead of a solid one. Determine the maximum shearing stress in the hollow shaft subjected to torsion, shown in fig. On the third floor of the building, while carrying out this welding job on the hollow shaft, two men were lining the hopper of the screw conveyor with rubber sheets. The shaft has a machined surface finish and an ultimate tensile strength of 552 mpa.
The strength of a shaft implies the maximum torque it can transmit. They use hollow shaft speed reducers and do not require transmission components such as couplings, chains, or sprockets, so virtually nothing rotating is exposed to the outside, and high safety is assured without use of a safety cover. Polar moment of inertia of a circular hollow shaft can be expressed as. It depends on torsional rigidity of the shaft since it renders the stiffness to the shaft. Shaft 1045 carbon hollow steel shaft thrust bearing upper 2tp 286tp regreasable angular contact with polyrex em grease 324tp 5810p oil lubricated angular contact or spherical with site glass up to 300% guide bearing lower 2tp 286tp grease prepacked, double shielded rolling bearings. Blind or through hollow shaft o12 mm 105000 pulses per. Incremental encoders, solid and hollow shaft, with hall effect.