Types of shaft keys pdf

The basic dimensions width and length remain the same jijr all types. Keys and keyways pdf, archived from the original pdf on 20100319, retrieved 20100319. Pipe and pipe fittings, materials and applications, pipe joints, screwed joints, welded connections, cementing, flange joints, spigot. The resulting friction is used to provide resistance to axial motion. A comparison between militzer and this method where the surface pressure is even, gives about 80 % higher value for. 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 types and their design bright hub engineering. In other words, a square key is equally strong in shearing and crushing. Allowable shear stress for the material of the shaft. Jun 12, 2016 there isnt one specific alloy for all shaft keys. They are rigid sleeve or muff couplingsthis is the basic type of coupling. 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.

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. In this article you will learn about different types of keys in database. Figure 1 shows the parts of a keyed joint and its assembly. Set screws often accompany parallel keys to lock the mating parts into place.

Rectangular keys, sometimes called flat keys, are generalpurpose components for shafts between 1. Transmission shafts can be found in a manual transmission gearbox. 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. Square keys are used for smaller shafts and rectangular faced keys are used for shaft diameters over 6. 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. The hub is slightly larger than the shaft and key to allow it to slide over the shaft during assembly. The key requires a circular type of keyway in the shaft. The key will have a provision in both the shaft and the machine element which needed to be connected. The sunk keys are provided half in the keyway of the shaft and half in the keyway of hub or boss of the pulley. Shaft and hub keyway and key sizes micromachineshop. Shafts a shaft is an element used to transmit power and torque, and it can support reverse bending fatigue. Most standards fail to discuss the important issue of key material, as well as their shape and installation. These keys are temporary fastening elements and are subject to the crushing and the shearing stress.

May 18, 2018 the key requires a circular type of keyway in the shaft. Therefore, it is used for comparatively light loads. The rounded ends make it easy to slide gears, hubs, and other components into place. Understand basic types of universal joints and how and when theymay be. Recognize and understand principles of miscellaneous shaft attachment. Rigid couplings are mainly used in areas where the two shafts are coaxial to each other. In a basic manual transmission design, the transmission gears are attached to the counter shaft permanently, spinning along with it. Machine shafts are the integral part of the machine itself. Recognize and understand principles of miscellaneous shaft. In mechanical engineering, a key is a machine element used to connect a rotating machine. The rectangular key is most common in either very small or very large shafts. 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. A simple shear stress calculation will demonstrate why these particular dimensions were chosen.

There are several types of shaft keys, each with their own particular role and application. Jan 19, 2018 mechanical shaft keys are used for transferring torque in automotive powertransmission systems. Our all stainless steel hubs are available in bore diameters ranging from 564 to 114. These types of keys are generally attached to the driving member e. 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. Tapered keys designed to be inserted from the end of the shaft after the hub is in position. Chapter 11 drive lines, differentials, drive axles, and power. Keys and keyways 51 introduction university of babylon. Shaft keys that reduce manufacturing costs and machine downtime. Understand basic types of universal joints and how and when theymay be used.

Shaft keys are important machine components designed to transmit torque and rotative force. Friction will help transmit torque and provide resistance to axial motion of the hub relative to. The difference between a shaft and an axle is that the shaft rotates to transmit power, and that it is subjected to fatigue. 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. A woodruff key is a form of sunk key where the key shape is that of a truncated disc, as shown in the figure. Shaft keys revisited dimensions of shaft keys, standardized many years ago, are commonly considered to be the main concern in applying these devices. Keyways are still the most common of all joints between shaft and hub. Keys connecting shafts to pulley hubs are commonly used to achieve reliable. Straight keys, with a square or rectangular cross section, are the most common type of key. Key dimensions were standardized about 150 years ago.

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. In frontwheeldrive cars, the input and counter shafts are actually the same thing. Keys cotters and joints shafts splined shafts keys keyways. 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.

Woodruff keys are semicircular, fitting partly into ab circular segment keyway with the remainder fitting into a longitudinal slot keyway in the mating part. Mechanical shaft keys are used for transferring torque in automotive powertransmission systems. Parallel keys zthe key seats in the shaft and the hub so that exactly. Couplings and keys objectives recognize different types of keys and their standard sizes. The tubular design makes the drive shaft strong and light. Objectives after studying this unit, you should be able to identify keys and their application, calculate forces on keys, and design keys. It is usually used for shafts less than about 60 mm diameter and the keyway is cut in the shaft using a milling cutter. It is a taper key which fits in a keyway in the hub and is flat on the shaft. The different styles and types of shaft couplings are summarized below.

Berg has a wide selection of hub sizes and styles to select from. W d 4 clarification needed h 2d 3 clarification needed. How to survive alone in the wilderness for 1 week eastern woodlands duration. 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. When installed, these keys fill oval keyways completely, reducing stress on the key and shaft. The gearbox does this through a complex arrangement of gears and shafts. Standard contains tables of recommended key sizes versus shaft.

A key is a data item that exclusively identifies a record. Understand basic types of universal joints and how and when they may be used. In other words, key is a set of column s that is used to uniquely identify the record in a table. The drive shaft, also called a propeller shaft, is commonly a hollow steel tube with yokes welded on the end. 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. 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. The pictures shows the stress pattern in a shaft with a keyway under pure torque. The diagram shows the importance of having a big and smooth radius at the bottom of the keyway, this is.

This cuts the length of each shaft to avoid drive line vibration. It is also stated that a minimum key length should be 25 % larger than the shaft diameter. It is always inserted parallel to the axis of the shaft. Chapter 11 drive lines, differentials, drive axles, and. What are the different types of keys in machine design. Recognize many types of couplings and their advantages and disadvantages. The counter shaft lies parallel to the main shaft and is driven by the input shaft through a pinion gear. Keys are used as temporary fastenings and are subjected to considerable crushing and shearing stresses. There are many types of couplings that fall under the rigid couplings category. Chapter 6 design of keys, splines and pins key terms. Understand principles of splines and analyze appropriate loads.

Friction will help transmit torque and provide resistance to axial motion of the hub relative to the shaft. Keys aroused as temporary fastenings and are subjected to considerable crushing and shearing stresses. This consists of a pipe whose bore is finished to the required tolerance based on the shaft size. It can be used with the tapered shaft because it aligns itself in the seat. 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 circular segment can be cut directly by plunge cutting with a circular. 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. The taper will impart a compressive contact pressure between the hub and the shaft. Insidepenton com electronic design adobe pdf logo tiny. Scope covers the dimensions and tolerances for parallel keys and keyways. 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. The diameter of shaft for flywheel is obtained from the maximum torque transmitted. Shaft keys that reduce manufacturing costs and machine.