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Fitting using hand skills
Published in David Salmon, Penny Powdrill, Mechanical Engineering Level 2 NVQ, 2012
If nuts are tightened too tight, the shank of a nut or bolt can be permanently stretched and weakened. For many applications it is important to tighten the bolt as tight as possible without causing any weakening. The maximum tightness allowed depends on a number of factors, principally the material and size of the stud/shank. The tightness of a bolt is measured in units of torque called Newton/metres. A torque wrench measures the amount of torque being applied to a bolt. Most torque wrenches use sockets, and are set by turning a screw on the handle to set the required torque. When the correct torque is applied, the torque wrench ‘clicks’.
Principles of Energy Conversion
Published in Hamid A. Toliyat, Gerald B. Kliman, Handbook of Electric Motors, 2018
Hamid A. Toliyat, Gerald B. Kliman
It is important that the proper foot bolt size and type be used to secure the motor to the foundation. The correct bolt torque for the type bolt being used should be applied with a torque wrench and checked after 24 hours of operation, after 3 months, and every 6 months thereafter. Table 11.23 gives the recommended torque for various thread sizes.
Testers and Tools
Published in Laurence J. Street, Introduction to Biomedical Engineering Technology, 2016
“Wrenches” includes everything from small open-end spanners to adjustable “Crescent” wrenches to metric and standard socket sets of every size (Figure 10.33). Some applications specify that fasteners be tightened to particular torque values and this requires an accurate torque wrench handle.
Interference screws 3D printed with polymer-based biocomposites (HA/PLA/PCL)
Published in Materials and Manufacturing Processes, 2023
J. Jamari, D.F. Fitriyana, P. S. Ramadhan, S. Nugroho, R. Ismail, A.P Bayuseno
A torque wrench was also used to perform the interference screw insertion tests. Under orthopedic surgery-like conditions, these screws are physically embedded through the holes and clamped once they are protected. A torque wrench was used to read the tightening torque values during the experiment. The following parameters are primarily measured during the intervention: a) Threshold Torque (TT) - the torque at which the screw begins to tighten in the bone; and b) Peak Failure Torque (PFT) - the torque at which the screw assembly starts to fail. Moreover, the torque test was used in the study to calculate TT value and PFT value in accordance with ASTM F2502 standards.[28] These two values can be derived from a torque curve, as shown in Fig. 4. The testing standard’s selected parameters could be used to evaluate bioabsorbable screws used in internal fixation implants. Accordingly, manufacturers of bioabsorbable screws must ensure that full healing occurs before the bioabsorbable screws degrade completely. Additionally, the fracture shape was also analyzed to determine whether the biocomposite under consideration in the study is ductile or brittle.
Bolt clamping force versus torque relation (F-T relation) during tightening and untightening the nut having slight pitch difference
Published in Mechanics Based Design of Structures and Machines, 2023
Xi Liu, Biao Wang, Nao-Aki Noda, Yoshikazu Sano, Yuto Inui, Kosuke Tateishi, Yasushi Takase
Figure 7 illustrates the boundary conditions for experiment. The bolt head is fixed and the nut is screwed onto the bolt manually by torque wrench until the nut is in contact with the clamped body; then, the nut is tightened through the device. Figure 8 illustrates the experimental device based on JIS B 1084 standard. During tightening, the tightening torque T, the clamping force F and the nut rotation angle θ are recorded. The molybdenum disulfide grease spray is used on the thread surface as lubricating oil; then, friction coefficient in thread surface μs and the friction coefficient in bearing surface μw are also measured by using the device during the nut tightening. During the nut untightening, the torque is measured manually by using a torque wrench and reading the clamping force recorded on the device at the same time.
Online monitoring for error detection in vat photopolymerization
Published in International Journal of Computer Integrated Manufacturing, 2023
Flavia Dalia Frumosu, Macarena Méndez Ribó, Shuo Shan, Yang Zhang, Murat Kulahci
The bottom-up MP VPP set-up used in this study (Figure 1), is an in-house built machine composed of three main building blocks: light source, drum-vat and the linear stage. Each one of these building blocks is accountable for the final quality of the built part. The light source comes from a DLP® projector (LUXBEAM® Rapid System – LRS-4 KA), which sequentially projects the cross sections of a geometry at a wavelength of 385 nm. The focus plane is located at the bottom of the vat.The drum-vat houses the photopolymer material. This set-up uses an antiadhesive fluorinated ethylene propylene (FEP) flexible membrane. The membrane, together with a drum-mechanism vat design, enables a self-peeling mechanism which significantly reduces the adhesive forces during the lifting campaign (Pedersen et al. 2016). The membrane tension is fixed with a torque wrench to ensure that the tension is distributed equally, in this case, a torque of 0.3 Nm was used.The linear stage oversees the vertical motion and it holds the build platform where the layers of the geometry are attached to it (Mu et al. 2017).