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Machine Tools
Published in David A. Stephenson, John S. Agapiou, Metal Cutting Theory and Practice, 2018
David A. Stephenson, John S. Agapiou
Most commonly, angular contact bearings are used at both ends of conventional or high-speed spindles. However, under high speed, moderate load conditions such as those typical of drilling, a tandem “O” bearing arrangement with three bearings as locating bearings on the work end and a single row of cylindrical roller bearings as a floating bearing on the drive end may be used. Under high load, average speed conditions such as those typical of milling, a bearing arrangement with two double-row cylindrical roller bearings such as radial bearings and a double direction angular contact thrust ball bearing to support the axial force may also used (Figure 3.58). Since tapered roller bearings can carry much higher loads than ball bearings, they save space because one tapered roller bearing is used at each end of the spindle (Figure 3.59), instead of two or three ball bearings. Standard tapered rolled bearings are normally used for high loads, lower speed applications, while moderate to high speeds (about 50 m/s) are achieved either with modified cage designs to direct the oil to the roller-rib contact area or by providing a secondary lubricant source to the rib.
Final drives and rear axles
Published in M.J. Nunney, Light and Heavy Vehicle Technology, 2007
A similarly mounted single-row, tapered roller bearing has sometimes been used in preference to a ball bearing. The tapered roller bearing comprises an inner ribbed cone, caged tapered rollers and an outer cup. In this case, the thrust loads acting on a wheel in the inward direction are freely transmitted through both half-shafts, via a central spacer, to the bearing on the other side of the axle. The reason for this side-to-side transfer of loading is that, acting alone, the conventional tapered roller bearing is capable of accepting axial thrust loading in one direction only.
Mill Rolls and Their Bearings
Published in William L. Roberts, Cold Rolling of Steel, 2017
The tapered roller bearing is the commonest bearing of this type employed in cold reduction mills, finding almost universal use as work roll bearings in 4-high mills and increasing use as backup roll bearings. In use since 1926,♦ these bearings are significantly more expensive than the sleeve or plain bearings discussed in Section 3-3, but exhibit significantly less friction and may, in many cases, be prepacked with lubricant, thus simplifying the construction of both the bearing and the roll chock.
Analysis of vibration and temperature on the axle box bearing of a high-speed train
Published in Vehicle System Dynamics, 2020
Zhiwei Wang, Yao Cheng, Paul Allen, Zhonghui Yin, Dong Zou, Weihua Zhang
The tapered roller bearing is a key component of high-speed trains and has a noticeable feature of high load capacity against axial and radial loads. However, the double-row tapered roller bearing (TRB) of the axle box is also one of the most vulnerable parts due to the load from the wheel–rail and bogie. Moreover, its dynamic performance directly affects the operational safety of high-speed trains and can even cause train derailment and serious accidents. The temperature and vibration of the axle box bearing can reflect its service state. As the temperature of the axle box bearing increases due to frictional heat at high rotational speed, its dynamic performance is likely to be affected [1] and vice versa [2]. Hence, increased temperature and vibration of the bearing are the critical parameters in axle boxes. Therefore, research into the dynamic and temperature characteristics of axle box bearings in high-speed trains is crucial in their design and optimum performance. In addition, the dynamic performance and temperature characteristics of the axle box bearing are useful for monitoring condition.
Prognostics Models for Railroad Tapered Roller Bearings with Spall Defects on Inner or Outer Rings
Published in Tribology Transactions, 2019
Constantine Tarawneh, Jennifer D. Lima, Nancy De Los Santos, Robert E. Jones
The heavy loads carried by a freight railcar are distributed equally among eight tapered roller bearings that sit at the ends of the wheel–axle assemblies. A typical tapered roller bearing, shown in Fig. 1, has one outer ring (cup) and two inner rings (cones) with rollers transferring the load between the cup and the cones. The bearing outer ring (cup) is supported on one side by the side frame of the truck/bogie. Hence, the load path travels from the railcar side frame to the bearing cup through the bearing adapter and from the cup to the cones through the rollers. The bearing cup is stationary and does not rotate unless it indexes slightly during service operation when the bearing is temporarily unloaded. The latter occurs when the railcar wheels hit a bump in the rail tracks, causing the side frame to briefly lose contact with the bearing adapter. Therefore, under normal bearing service operation, the top hemisphere of the cup is always loaded and is referred to as the loaded zone, whereas, the bottom hemisphere of the cup is referred to as the unloaded zone. The bearing inner rings (cones) are press-fit to the axle and rotate synchronously with the axle and wheels, undergoing cyclical loading and unloading as they rotate through the loaded and unloaded zones (Tarawneh, et al. (1)).
Dynamic analysis and frequency response of cylindrical roller bearing of an airflow root blower
Published in Cogent Engineering, 2022
Themba Mashiyane, Dawood Desai, Lagouge Tartibu
The roller bearings used in machinery come in different types such as cylindrical roller bearing, spherical roller bearing, tapered roller bearing, thrust bearing, etc. An airflow root blowers being one of such machines that operate in a compression range of 1.1–1.2 (Verma, 2014) and are used to discharge compressed air/demineralized water into a mechanical system at a steady flow rate, depending on the system requirement, it uses a cylindrical roller because the bearing has a high load-bearing capacity, and it is capable of operating efficiently under moderate speed and heavy-duty applications (Sehgal et al., 2000; Upadhyay et al., 2013; Sharma et al., 2014, 2015).