China
Africa
Explore chapters and articles related to this topic
What Is This Thing Called Lean Manufacturing?
Published in Bob Sproull, Theory of Constraints, Lean, and Six Sigma Improvement Methodology, 2019
The next step in the process is referred to as interior turning and, again, there are two interior turning machines labeled B1 and B2, one on each side. In the third step, there were two possible choices for drilling, C1 and C2. After the pinion was automatically inspected for cracks (with one, common automated gage), it then progressed to one of two hobbing machines, D1 and D2. The parts were then collected in storage bins and sent as large batches to an outside vendor for heat treatment. Upon return from heat treatment, the pinions then proceeded to hard hobbing, E1 and E2, and then on through the remainder of the process as indicated in Figure 2.5. Hobbing is a machining process used for gear cutting, cutting splines, and cutting sprockets on a hobbing machine, which is a special type of milling machine. The teeth or splines are progressively cut into the workpiece by a series of cuts made by a cutting tool called a hob. Compared with other gear forming processes, it is relatively inexpensive but still quite accurate, thus it is used for a broad range of products.
Generic Gear Shapes
Published in Stephen P. Radzevich, Theory of Gearing, 2018
The following three important conclusions can be drawn from this discussion: The total number of feasible generic gear surfaces is not infinite but a finite number. This means that it is possible to count and investigate all possible designs of gears machined on conventional gear generators.Gears with any of the generic gear shapes are convenient for machining, as only rotations and translations are required to reproduce the required motion of the gear-cutting tool in relation to the work gear.An appropriate area of application can be found for all the gears briefly discussed in this section of the monograph.
Gear-Design Trends
Published in Stephen P. Radzevich, Dudley's Handbook of Practical Gear Design and Manufacture, 2016
Gear cutting is done mostly by conventional hobbing or shaping machines. Some gears are shave and then heat-treated, while others are heat-treated after cutting and then ground. In this field of work, the volume of production is much lower and the size of parts is much larger than in the vehicle-gear field. Both these conditions make it harder to keep heat-treat distortion well under control that the teeth may be finished before hardening.
Nonedible vegetable oil-based cutting fluids for machining processes – a review
Published in Materials and Manufacturing Processes, 2020
Rahul Katna, M. Suhaib, Narayan Agrawal
Straight oils are petroleum or mineral oils without water.[94] They are also called as neat oils. These are used as-is or “straight” without adding any water or being diluted. These are formulated from mineral oils or vegetable oils by mixing them with different additives as performance enhancers and find application where more lubrication is required than cooling. Among the other types of cutting fluids, these provide the highest cushioning effect. However, these have drawbacks like poor thermal stability and heat transfer capacity, high flammability, high cost, and low efficiency at high cutting speeds.[95,96] Additives are added to improve machining efficiency at extreme loads, to reduce foaming and mist formation. These are used in threading, broaching, drilling, gear cutting, etc.[70] Contact with water causes rancidity and makes them susceptible to microbial attack. These drawbacks limit the application of straight oils in high-speed machining operations. It was seen that mixing water with oil can offer a significant improvement in machining performance in comparison to using straight oils alone. Thus soluble oils were formulated.
User experience evaluation model for sustainable manufacturing
Published in International Journal of Computer Integrated Manufacturing, 2018
Margherita Peruzzini, Marcello Pellicciari
In terms of knowledge formalisation, this research is inspired from the approach proposed by Germani, Mandolini and Cicconi (2011), according to which manufacturing technologies are divided into classes (e.g. chip-forming machining, injection moulding, stamping, die-casting and painting) and in turn into categories (e.g. machining is subdivided into milling, turning, grinding, gear cutting, broaching and slotting). Each category is characterised by a set of typical operations, which are expressed by mathematical formulas using those geometrical parameters characterising the specific operation (e.g. length, width, depth and roughness). A similar procedure is performed for assembly because the assembly modalities (e.g. sequence of assembly, position of the operator, devices to be used and difficulties in handling) can be linked by mathematical formulas to the product’s geometric features. Information is taken from both single part and assembly 3D models according to the specific manufacturing feature to be determined. Finally, manufacturing and assembly operations are mapped with a specific set of geometric and non-geometric elements defined as a set of manufacturing and assembly features. In this way, the 3D product model can be represented as a collection of manufacturing features that can be exploited to anticipate the manufacturing processes. Knowing the manufacturing process in advance allows applying cost models, LCA models and UX models during the design stages to estimate the impacts of product features on cost, environmental impact and UX impact, respectively.
Study on the quality and tooth root load carrying capacity of the high contact ratio asymmetrical gear tooth machined using WCEDM process
Published in Materials and Manufacturing Processes, 2020
Rama Thirumurugan, Clement Christy Deepak C
Gupta and Jain[18] reported the comparative performance study of spur gear cutting processes such as gear hobbing and WCEDM process and established that WCEDM process, when compared to conventional gear hobbing process, is a superior, economical, and viable alternative for manufacturing the high-quality miniature gears. They recommended low voltage and pulse-on time, avoiding the high pulse-off time, maximum values of wire feed rate and cutting speed to get the high quality miniature gears.[19] Ali et al.[20] compared the performance of conventional WCEDM and Micro WCEDM processes in cutting the miniaturized spur gear and found the that smaller diameter wire and low energy discharge process parameters are required to get the good surface finish.