Gear Bearing Research Project PDF

Republic of the Philipphines BULACAN STATE UNIVERSITY City of Malolos, Bulacan COLLEGE OF INDUSTRIAL TECHNOLOGY DRAFTING TECHNOLOGY DEPARTMENT Gear Bearing “A...

Republic of the Philipphines BULACAN STATE UNIVERSITY City of Malolos, Bulacan COLLEGE OF INDUSTRIAL TECHNOLOGY DRAFTING TECHNOLOGY DEPARTMENT Gear Bearing “A RESEARCH PROJECT FOR KINETICS AND DYNAMICS OF MACHINERY” SUBMITTED BY: SUBMITTED TO: Reyes, Reech Jay O. Ms. Marjorie O. Pagdanganan Beriso, Angelica G. BIT DT 3G-G2 Kinetics and Dynamics of Machineries  2 Introduction A bearing, is a mechanical element in motion that supports and decreases friction, it is a highly engineered component made with high precision that actively help a machinery to move in extremely high speed with ease and efficiency to carry remarkable loads. Bearings are often used to allow one part to rotate or move smoothly relative to another part. If something twists, turns or moves, it probably has a bearing in it. Bearings offers high precision, reliability and durability, as well as the ability to rotate at high speeds with minimal noise and vibration. The bearing consists of an outer ring, an inner ring, rolling elements (balls), a cage, seals or shields, and a lubricant. The outer ring is stationary and the inner ring is rotating. Balls are typically made of steel or ceramic. The cage maintains equal spacing between balls. In order for the surfaces to provide efficient axial meshing, the teeth must either be beveled or made with engagement. This avoids misalignment, sticking, and reduces sliding friction in the bearing. Bearings are classified into three types: ball bearings, roller bearings, and plain bearings. These three types of bearings have its own designated uses and features that makes a gear move fast and smooth. Kinetics and Dynamics of Machineries  3 Characteristics of Bearings Load – Ball bearings have a lower load capacity per size compared to other rolling- element bearings because the contact area between the balls and races is smaller. However, they can withstand high radial and dynamic loads, but are less resistant to axial and static loads. The load capacity is proportional to the bearing's outer diameter multiplied by its width. Speed - Specific bearing types and arrangements usually offer speed ratings which include both the reference speed (based on thermal conditions) and the limiting speed (based on mechanical limits). However, using complex cage executions, high- precision bearings, and advanced types of methods and lubrication, it is possible to operate a bearing at speeds greater than its reference speed or even the limiting speed. Torque And Noise - Torque in a bearing is the rotational force required for turning the bearing, and noise level is the sound produced during its operation. Inclination Of Inner/Outer Rings - Inclination develops between the outer and inner rings of a bearing when there is inadequate precision of the shaft and housing, mounting problems, or shaft deflection. However, the internal clearance of the bearing will allow for a certain amount of inclination. Rigidity- When loads are applied to bearings, there is elastic deformation in the contact areas between the rolling elements and the raceways. The extent of this deformation varies based on the bearing’s dimensions, type, and the applied load. Bearings with larger dimensions tend to exhibit greater rigidity. Kinetics and Dynamics of Machineries  4 Mounting and Dismounting – A single-row deep groove ball bearings are non-separable, it’s important to consider periodic inspections and replacements when designing the shaft and housing. Axial Positions and Directions - Bearings equipped with a flange and a locating snap ring are more efficient for orienting in the axial direction. Classifications of Bearings Ball bearings come in various designs to suit different applications and requirements. There are three main classifications of ball bearings. Radial Bearings – are ball bearings designed to support radial loads, which are loads acting perpendicular to the shaft. They are commonly used in applications where the main load is radial, such as in most standard rotating machinery. Angular Contact Ball Bearings - are designed to support both radial and axial loads. They are particularly suitable for applications where the load is not purely radial or axial but a combination of both. Thrust Ball Bearings - are designed to support axial (thrust) loads, which are loads acting along the axis of the shaft. They are used in applications where the primary load is axial and there is a need to withstand axial forces. These classifications represent broad categories, and there are numerous variations and specialized designs within each category to meet specific application needs. Choosing the Kinetics and Dynamics of Machineries  5 right type of ball bearing depends on factors such as the type of load, speed, precision requirements, and environmental conditions in which the bearing will operate. Bearing Application Bearings are employed in a wide range of applications, including aircraft control and airframe, aerospace, agriculture, automotive, ball screw support, instrument or miniature, medical or dental, military, pump, spindle or high precise, and sporting and consumer goods. Bearings designed for aircraft control and aerospace applications are engineered specifically for these demanding environments. They can be made from a ball, roller, or needle roller and are designed to withstand the harsh conditions found in aircraft engines and helicopters. These bearings are also suitable for use in agricultural equipment and environments, as well as in the automotive industry. Bearings specifically designed for ball screw and lead screw applications are also available. The majority of ball screw support bearings are angular contact bearings with a steep contact angle, such as 60°, and come in duplex, triplex, and quadruple configurations. Bearings with separate thrust and radial roller bearings in a single unit are another option. Kinetics and Dynamics of Machineries  6 Cartridge designs with a casing, seals, and bearings are also available. Instrument and tiny bearings are small deep groove or angular contact bearings. They are utilized in dental drills and computer disk drives since they require very little bearings. Bearings are also specially designed for medical or dental equipment, as well as for military applications in accordance with U.S. Government standards. Bearings designed for the conditions found in pumps, including high loads, poor or degraded lubrication, and high operating temperatures, are also available. Bearings for sporting and consumer goods include those used in inline skates, skateboards, and fishing reels. Design Features A ball bearing is a type of bearing that consists of two main rings: the inner ring on the rotating shaft and the outer ring in a stationary component. The balls are rolling elements made of steel or ceramic, designed to reduce friction and distribute load evenly. The cage or retainer holds and separates the balls, maintaining equal spacing for smooth operation. Seals or shields protect the internal components from contaminants and prevent lubrication. The internal clearance affects the bearing's ability to accommodate thermal expansion, manufacturing tolerances, and misalignment. The contact angle between the balls and raceways determines the bearing's ability to handle axial and radial loads. Preload may be applied to enhance stiffness in high-precision applications. The materials used influence strength, durability, and corrosion resistance. Kinetics and Dynamics of Machineries  7 Parts of Ball Bearing Figure 1: Parts of Ball Bearing© Outer Ring - The outer ring is the stationary part of the bearing and is usually mounted into a housing. Inner Ring - The inner ring is the rotating part of the bearing and is mounted onto a shaft. Rolling Element “Balls” - These are the rolling elements that reduce friction between the inner and outer races. They are typically made of steel or ceramic. Cage - The cage holds and separates the balls, preventing them from coming into direct contact with each other. It also helps maintain equal spacing between the balls. Seals/Shields - Ball bearings may have seals or shields to protect the internal components from contaminants and prevent lubricant leakage. Seals provide better protection but may increase friction compared to shields. Kinetics and Dynamics of Machineries  8 Lubricant - Bearings are often filled with lubricating grease or oil to reduce friction and wear between the moving parts. The primary function of a ball bearing is to reduce friction and facilitate smooth rotation between two moving parts. Ball bearings are a type of rolling-element bearing, and they achieve this by using balls as rolling elements placed between the inner and outer races. Types of Bearings Bearings are designed for specific applications and conditions. They include deep groove ball bearings, angular contact ball bearings, and thrust ball bearings. Roller bearings include cylindrical, tapered, spherical, needle roller, and tapped roller bearings. Plain bearings include sleeve, flanged, and thrust washers. Specialized bearings include radial ball bearings with angular contact, which combine radial and axial contact features. Mounted bearings are pre-assembled into housings, simplifying installation. These bearings are commonly used in various industries, such as automotive transmissions and industrial machinery. Each type of bearing has its advantages and limitations, and the choice depends on factors such as load type, magnitude, speed, precision requirements, and environmental conditions. Ball Bearing Mechanical components used to reduce friction between rotating parts. They consist of steel balls or ceramic spheres that roll between two races, typically an inner and Kinetics and Dynamics of Machineries  9 an outer race, to facilitate smooth and efficient movement. The balls are contained within a cage or retainer that maintains their spacing and prevents them from contacting each other. This design allows for low friction and enables the transfer of radial and axial loads. Ball bearings are widely used in various applications, including machinery, automotive systems, electric motors, and rotating equipment, where they provide reliable support and reduce frictional losses. Here are some of the most common types of ball bearings used in various applications. a. Deep Groove Ball Bearings: These are the most widely used type of ball bearings. They have a deep groove design, allowing them to support both radial and axial loads in multiple directions. b. Angular Contact Ball Bearings: These bearings are designed to handle combined radial and axial loads. They have raceways in the inner and outer rings that are inclined at an angle, allowing them to support axial loads in one direction. c. Thrust Ball Bearings: Thrust ball bearings are designed to handle axial loads in a single direction. They have a flat surface on the housing washer and a grooved surface on the shaft washer to facilitate proper alignment. d. Self-Aligning Ball Bearings: These bearings have the ability to self-align, compensating for misalignment between the shaft and housing. They have two rows of balls and are commonly used in applications with shaft deflection or misalignment. Kinetics and Dynamics of Machineries  10 e. Miniature and Instrument Ball Bearings: These are small-sized ball bearings typically used in precision instruments, small motors, and other applications with limited space. They are available in various sizes and configurations. f. Cylindrical Roller Thrust Bearings: While not strictly "ball" bearings, cylindrical roller thrust bearings utilize cylindrical rollers instead of balls. They are designed to handle high axial loads and have improved load-carrying capacity compared to thrust ball bearings. g. Four-Point Contact Ball Bearings: These bearings have a unique design with four points of contact between the balls and raceways. They can support both radial and axial loads and are commonly used in applications like crane swivels and excavators. h. Duplex Ball Bearings: Duplex bearings consist of two single-row angular contact ball bearings paired back-to-back or face-to-face. They are used to handle higher axial loads and provide increased stiffness and precision. Roller Bearings Are mechanical components used to reduce friction between moving parts. They consist of cylindrical or tapered rollers that roll between two races, an inner and an outer race, to support radial and axial loads. Roller bearings distribute the load over a larger surface area compared to ball bearings, allowing them to handle heavier loads and provide increased load capacity. The rollers are held in place by a cage or retainer, which maintains proper spacing and prevents the rollers from contacting each other. Roller bearings are commonly Kinetics and Dynamics of Machineries  11 used in various applications, including industrial machinery, automotive systems, construction equipment, and more, where they provide smooth and reliable motion while minimizing friction and wear. a. Cylindrical Roller Bearings: These bearings have cylindrical rollers that are slightly longer than their diameter. They can handle heavy radial loads and some axial loads. They are available in various designs, such as single row, double row, and full complement configurations. b. Tapered Roller Bearings: Tapered roller bearings consist of tapered rollers and inner and outer races with tapered surfaces. They can support both radial and axial loads and are commonly used in applications where significant axial forces are present, such as in automotive wheel hubs and gearboxes. c. Spherical Roller Bearings: Spherical roller bearings have barrel-shaped rollers that are guided by inner and outer ring raceways with a common sphered surface. They are self-aligning and can accommodate misalignment, making them suitable for applications with shaft deflection or misalignment. d. Needle Roller Bearings: Needle roller bearings have long, thin rollers that have a high length-to-diameter ratio. They are used in applications with limited space and can handle high radial loads while having a small cross-sectional profile. e. Tapered Roller Thrust Bearings: These bearings consist of tapered rollers and two thrust washers. They can handle heavy axial loads in a single direction and have high axial stiffness. Kinetics and Dynamics of Machineries  12 f. Cylindrical Roller Thrust Bearings: Cylindrical roller thrust bearings utilize cylindrical rollers and are designed to handle high axial loads. They have relatively low radial load capacity. g. Spherical Roller Thrust Bearings: Spherical roller thrust bearings have barrel- shaped rollers and can accommodate high axial loads. They are self-aligning and can handle misalignment. h. Crossed Roller Bearings: Crossed roller bearings have cylindrical rollers arranged in a crisscross pattern. They can handle both radial and axial loads simultaneously and are often used in precision positioning applications. Materials Figure 2: 3D Drawing of Ball Bearing | Illustrated by Angelica Beriso A variety of specialized materials and plating options can be employed for ball bearings, including stainless steel, plastic, ceramic balls, ceramic races, and various platings. Ball bearings are typically constructed from through-hardened materials with a minimum Rockwell hardness of 58 RC. Although 440C stainless steel and SAE 52100 steel are the most common materials used for raceway and ball designs, these alloys are not suitable for Kinetics and Dynamics of Machineries  13 operating or friction temperatures exceeding 350° F. Molybdenum steels, on the other hand, exhibit exceptional temperature tolerance, even at temperatures surpassing 1000° F. Figure 3: Base Materials | Engineering360 © Operating Specification Ball bearings are crucial for selecting the right one for a specific application. These specifications include load capacity, speed limit, precision and tolerance, temperature range, lubrication requirements, mounting and fit, alignment, sealing and shielding, vibration and noise levels, corrosion resistance, maintenance requirements, and operating life. The bearing's capacity to handle specific loads, speed limit, precision and tolerance, and temperature range must be considered. Proper lubrication is essential for the performance and longevity of the bearing. Proper alignment of shafts and housing is crucial to prevent excessive loads and premature wear. Seals or shields may be necessary in environments with high vibration and noise levels. Maintenance requirements should align with the application's demands. Manufacturing Procedure The fabrication of a gear bearing generally necessitates processes such as precise Kinetics and Dynamics of Machineries  14 machining, thermal treatment, and assembly. Raw components are machined to produce the gear and bearing components, followed by thermal treatment to enhance hardness and durability. Precision is paramount to guarantee proper gear meshing. Finally, the gears and bearings are assembled to form the final product. Specific details may differ based on the gear bearing's type and design. Potential Causes of Bearing Failures Lubrication Failure Cause: Inadequate lubrication, use of inappropriate lubricants, or extreme temperatures that damage the lubricant. Solution: Use a proper type and amount of lubricant, avoid grease loss, and relubricate at the appropriate intervals. Contamination Cause: Caused by foreign substances making their way into cleaning solutions or bearing lubricants. Including dirt, dust, abrasive grit, steel chips from dirty hands or tools and tainted workspaces. Solution: Filter the lubricant and clean work spaces, tools, fixtures, and hands to minimize the possibility of contamination. Improper Mounting Cause: Lack of proper instruction, knowledge, and training in installing a mount. Kinetics and Dynamics of Machineries  15 Solution: Follow proper mounting instructions to understand the difference of proper and improper mounting. Misalignment Cause: Bent shafts, out-of-square shaft shoulders, out-of-square spacers, out-of-square clamping nuts and inappropriate installation due to loose fittings. Solution: Inspect shafts and housings for shoulder and bearing seat runout, and use precision-grade locknuts. False Brinelling Cause: Rapid movements of balls in the raceway while the idle equipment wears the lubrication, lack of rotation in the bearing due to fresh lubricant not returning to the spot Solution: Remove or absorb the external vibration that’s causing the ball to move, always use lubricants with anti-wear additives. Corrosion Cause: Moisture, acid, low quality or broken-down grease, improper wrappings and condensation from frequent temperature changes. Solution: Use proper bearing materials, divert corrosive fluids, choose integrally sealed bearings and consider external seals for hostile environments. Electrical Damage (Fluting) Cause: Continuous passage of direct or alternating current, even with low currents. Solution: Avoid electrical currents flowing through the bearing using insulated bearings. Kinetics and Dynamics of Machineries  16 Fatigue (Spalling) Cause: Overloading, excessive preload, tight ring fits, and usage of bearing beyond calculated fatigue life. Solution: Consider redesign bearings with more calculated fatigue life. Overheating Cause: Excessive operating temperatures and improper lubrication. Solution: Thermal or overload controls, supplemental cooling and adequate heat paths. Excessive Loads Cause: Far amount of loads are put in the bearing. Solution: Use a bearing with greater load capacity. Improper Storage and Handling Cause: Opening and tearing wrappings prematurely, storing bearing in high temperatures, and exposing bearing to dampness and dust. Solution: Store bearing in room temperature or dry are, cover bearings, keep them clean, and take bearings to the installation site before unwrapping. Fit Cause: Tight fit, loose fit, and excessive loading of the rolling element when interference fits exceed the radial clearance at operating temperatures. Solution: Choose proper clearance and refer to the manufacturer’s installation guide Kinetics and Dynamics of Machineries  17 Technical Terms Bearing - mechanical element in motion that supports and decreases friction. Rolling Elements – typically steel or ceramic, are used to reduce friction between inner and outer races of a bearing. Cage - effectively separates and holds the balls, preventing direct contact and maintaining equal spacing in a bearing. Seals / Shield – Protects bearing from contamination and also use for lubricant retention. Load – is the work capacity of a bearing. Rigidity – one of the characteristics of a bearing which means toughness. Lubrication – application of a lubricant, such as oil or grease, to reduce friction and wear between the moving parts of the bearing. Mounting – A housing essential to guarantee the bearing performs at its best, with the least amount of friction, correct alignment, and maximum efficiency. Torque or Noise – refers to the rotational force required for turning, while noise level refers to the sound produced during its operation. Fatigue – Overloading or excessive load on a bearing. Kinetics and Dynamics of Machineries  18 References: https://en.wikipedia.org/wiki/Ball_bearing https://www.emersonbearing.com/products/roller-bearings/ https://www.skf.com/group/products/rolling-bearings/principles-of-rolling-bearing- selection/general-bearing-knowledge/bearing-basics https://www.nskamericas.com/en/tech-center/bearing-basics/ https://www.skf.com/group/products/rolling-bearings/bearing-designation-system https://www.skf.com/group/products/plain-bearings/spherical-plain-bearings-rod- ends/principles/designs-features https://www.reliableplant.com/Read/30255/reasons-bearings-fail https://www.ezo-brg.co.jp/english/product/document-detail02.html https://tameson.com/pages/ball-bearing https://www.youtube.com/watch?v=UhMz44y_EwY https://www.youtube.com/watch?v=ZTsqt2zKz-8 https://insights.globalspec.com/article/1288/ball-bearings-specifications-and-selection- criteria-for-engineers Kinetics and Dynamics of Machineries  19 Reflections Angelica G. Beriso (3G-G2) Our research has transcended the technical aspects of bearings, revealing their profound impact on our daily lives. They enable the smooth operation of countless machines, enhancing our comfort, productivity, and safety. By understanding bearings, we gain a deeper appreciation for the intricate engineering that underpins our modern world. Reech Jay O. Reyes (3G-G2) Our research has taught me a lot about gear bearings. It gives me vast knowledge how interesting it can be because of its details and functions. As one of the researchers for this certain topic, I can now say that a gear bearing plays a very big part in all machineries, it is one of the most essential part a machine should have for it to function more efficiently. With this research project that we conduct, I can assure that with the use of bearings in all machine the world will advance and grow more with the help of industrial machineries. Kinetics and Dynamics of Machineries