Types of shaft keys pdf

Recognize and understand principles of miscellaneous shaft. Chapter 11 drive lines, differentials, drive axles, and. The diagram shows the importance of having a big and smooth radius at the bottom of the keyway, this is. These keys are temporary fastening elements and are subject to the crushing and the shearing stress. Shafts, splined shafts, keys, keyways, types of keys, light and heavy duty keys, comparision between keys and cotters, cotter joints and knuckle joints. Video lecture on definition of shaft and its explanation from design of shafts, keys and couplings chapter of design of machine for mechanical engineering students. Keys and keyways pdf, archived from the original pdf on 20100319, retrieved 20100319. Type c keys with both ends round hole for one retaining screw for sizes 8 x7 and upwards and for key lengths above the stepped line in table 4 1.

A simple shear stress calculation will demonstrate why these particular dimensions were chosen. The drive shaft, also called a propeller shaft, is commonly a hollow steel tube with yokes welded on the end. In other words, a square key is equally strong in shearing and crushing. The taper will impart a compressive contact pressure between the hub and the shaft. The pictures shows the stress pattern in a shaft with a keyway under pure torque. A comparison between militzer and this method where the surface pressure is even, gives about 80 % higher value for. Therefore, it is used for comparatively light loads. Shaft keys are important machine components designed to transmit torque and rotative force. Berg has a wide selection of hub sizes and styles to select from. These types of keys are generally attached to the driving member e. Understand basic types of universal joints and how and when theymay be used.

Pipe and pipe fittings, materials and applications, pipe joints, screwed joints, welded connections, cementing, flange joints, spigot. It is used to fetch or retrieve records datarows from data table according to the conditionrequirement. Sunk keys the sunk keys are provided half in the keyway of the shaft and half in the keyway of the hub or boss of the pulley. It is a taper key which fits in a keyway in the hub and is flat on the shaft. Keys and keyways 51 introduction university of babylon. Recognize and understand principles of miscellaneous shaft attachment. A adapter sleeve components b ball joints balls bars bearings belts bushings bushings, taper bushings c calipers chain chain guides clamping plates conveyor rollers motorized corrosion protection couplings d e elements f fork joints g gear rack gears grease fittings grips h handles hexagon bars hydraulic i j k keyless locking rings keys knobs l. Shafts a shaft is an element used to transmit power and torque, and it can support reverse bending fatigue. Understand principles of splines and analyze appropriate loads. Square keys are used for smaller shafts and rectangular faced keys are used for shaft diameters over 6.

The different styles and types of shaft couplings are summarized below. Mechanical shaft keys are used for transferring torque in automotive powertransmission systems there are many shaft keys for costeffective and efficient power transmission, which includes square keys, parallel keys, rectangular keys, woodruff keys, taper and gribhead keys, and feather keys. Keys connecting shafts to pulley hubs are commonly used to achieve reliable. Machine shafts are the integral part of the machine itself. Keys are used as temporary fastenings and are subjected to considerable crushing and shearing stresses. The tubular design makes the drive shaft strong and light. The counter shaft lies parallel to the main shaft and is driven by the input shaft through a pinion gear. A key is a data item that exclusively identifies a record.

There is a special p keyway designed to accept any of the 7 keys and a special key blank designed to be accepted into all 7 keyways, 35101 l which is made of stainless steel and requires a special machine to cut. Couplings and keys objectives recognize different types of keys and their standard sizes. The key will have a provision in both the shaft and the machine element which needed to be connected. Shaft keys types and their design bright hub engineering. 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. When installed, these keys fill oval keyways completely, reducing stress on the key and shaft. Metric standard parallel keyway and key sizes shaft diameter mm keyway mm key mm from to width w depth h width w depth t 6 8 2 1. There are many shaft keys for costeffective and efficient power transmission, which includes square keys, parallel keys, rectangular keys, woodruff k. Chapter 6 design of keys, splines and pins key terms.

Figure 1 shows the parts of a keyed joint and its assembly. Half part of its nominal thickness is sunk in the shaft key way and the remaining half portion fits in the keyway inside the hub or boss of the mating piece. For making the joint, grooves or keyways are cut on the surface of the shaft and in the hub of the part to be mounted. Friction will help transmit torque and provide resistance to axial motion of the hub relative to the shaft. May 18, 2018 the key requires a circular type of keyway in the shaft.

Shaft keys that reduce manufacturing costs and machine downtime. The purpose of a transmission gearbox is to transfer the high output of an automobiles engine to the wheels, and in the process reduce it to a compatible speed. There are several types of shaft keys, each with their own particular role and application. The basic dimensions width and length remain the same jijr all types. Jun 12, 2016 there isnt one specific alloy for all shaft keys.

Straight keys, with a square or rectangular cross section, are the most common type of key. A woodruff key is a form of sunk key where the key shape is that of a truncated disc, as shown in the figure. Rectangular keys, sometimes called flat keys, are generalpurpose components for shafts between 1. Woodruff keys are semicircular, fitting partly into ab circular segment keyway with the remainder fitting into a longitudinal slot keyway in the mating part. This cuts the length of each shaft to avoid drive line vibration. What are the different types of keys in machine design. It is usually used for shafts less than about 60 mm diameter and the keyway is cut in the shaft using a milling cutter. Rather, there is a set of material property requirements and a range of steel alloys and heat treatment combinations that would meet those requirements. Shaft and hub keyway and key sizes micromachineshop. The resulting friction is used to provide resistance to axial motion. Jan 19, 2018 mechanical shaft keys are used for transferring torque in automotive powertransmission systems. Beam couplings the beam coupling consists of single or multiple helical cuts in the coupling body which typically can accommodate parallel misalignments up to 0. Keyways are still the most common of all joints between shaft and hub. Key dimensions were standardized about 150 years ago.

The rounded ends make it easy to slide gears, hubs, and other components into place. Mar 01, 2016 video lecture on definition of shaft and its explanation from design of shafts, keys and couplings chapter of design of machine for mechanical engineering students. The rectangular key is most common in either very small or very large shafts. A key is a piece of mild steel inserted between the shaft and hub or boss of the pulley to connect these together in order to prevent relative motion between them. This pa note will explain the uses of keys and keyways in pulleys and bushings, and present current industry standards for key and keyway component sizing. Transmission shafts are used to transmit power between the source and the machine absorbing power. The gearbox does this through a complex arrangement of gears and shafts. Allowable shear stress for the material of the shaft. It is also stated that a minimum key length should be 25 % larger than the shaft diameter. Set screws often accompany parallel keys to lock the mating parts into place.

The sunk keys are provided half in the keyway of the shaft and half in the keyway of hub or boss of the pulley. There are 7 different keyways c,ce,e,ef,f,fg and g. Keys are machine elements used to prevent relative rotational movement between a shaft and the parts mounted on it, such as pulleys, gears, wheels, couplings, etc. Scope covers the dimensions and tolerances for parallel keys and keyways. Shaft and hub keyway and key sizes keys connecting shafts to pulley hubs are commonly used to achieve reliable noslip power transmission in belt drive systems. Shaft keys are available in a variety of types and include parallel keys, square keys, flat keys, rectangular. Chapter 11 drive lines, differentials, drive axles, and power. Understand basic types of universal joints and how and when they may be used. W d 4 clarification needed h 2d 3 clarification needed. Understand basic types of universal joints and how and when theymay be. The circular segment can be cut directly by plunge cutting with a circular. Basic concept a key is a fastening inserted into the keyway of two mating parts, it is used to transmit torque from a shaft to a hub or vice versa.

There are many types of couplings that fall under the rigid couplings category. This consists of a pipe whose bore is finished to the required tolerance based on the shaft size. Most standards fail to discuss the important issue of key material, as well as their shape and installation. They are rigid sleeve or muff couplingsthis is the basic type of coupling. Keys aroused as temporary fastenings and are subjected to considerable crushing and shearing stresses. The diameter of shaft for flywheel is obtained from the maximum torque transmitted. The key requires a circular type of keyway in the shaft. In frontwheeldrive cars, the input and counter shafts are actually the same thing. Transmission shafts can be found in a manual transmission gearbox. Type c keys with both ends round hole for one retaining screw for sizes 8 x7 and. Shaft keys, shaft key design, rectangular keys, square keys, woodruff keys, gib keys, taper keys. It can be used with the tapered shaft because it aligns itself in the seat.

The larger depth of keyway prevents the tendency of the key to slip over the shaft, but it weakens the shaft more than that by the use of straight keys. In other words, key is a set of column s that is used to uniquely identify the record in a table. In mechanical engineering, a key is a machine element used to connect a rotating machine. A wide variety of types of shaft key options are available to you, such as gear, spline, and eccentric. Mechanical shaft keys are used for transferring torque in automotive powertransmission systems. How to survive alone in the wilderness for 1 week eastern woodlands duration. Tapered keys designed to be inserted from the end of the shaft after the hub is in position.

Our all stainless steel hubs are available in bore diameters ranging from 564 to 114. It is always inserted parallel to the axis of the shaft. In this article you will learn about different types of keys in database. Most shafts have circular cross sections, either solid or tubular. Friction will help transmit torque and provide resistance to axial motion of the hub relative to. Parallel keys zthe key seats in the shaft and the hub so that exactly. Rigid couplings are mainly used in areas where the two shafts are coaxial to each other. Objectives after studying this unit, you should be able to identify keys and their application, calculate forces on keys, and design keys.

Insidepenton com electronic design adobe pdf logo tiny. Shaft keys that reduce manufacturing costs and machine. Standard contains tables of recommended key sizes versus shaft. In a basic manual transmission design, the transmission gears are attached to the counter shaft permanently, spinning along with it. Recognize many types of couplings and their advantages and disadvantages. Keys cotters and joints shafts splined shafts keys keyways. In order to find the length of the key to transmit full power of the shaft, the. A sunk key is a key in which half of the thickness of key fits into the keyway in the shaft and half in the keyway of the hub. Shaft keys revisited dimensions of shaft keys, standardized many years ago, are commonly considered to be the main concern in applying these devices. The difference between a shaft and an axle is that the shaft rotates to transmit power, and that it is subjected to fatigue.