Hypoid bevel gears

API GL-4. Lubricants intended for axles with spiral bevel gears operating under moderate to severe conditions of speed and load or axles with hypoid gears operating under moderate speeds and loads. These oils may be used in selected manual transmissions and transaxle applications, where API MT-1 lubricants are unsuitable. 

Hypoid gears Similar in general form to bevel gears, hypoid gears operate on nonintersecting axes (Fig. 5.25). 

Types of gears are spur, helical, bevel (straight, spiral, zerol, and hypoid), and worm, each of which is discussed in the following sections. Table 57.1 summarizes the characteristics of each gear. 

Gears are associated with nearly every human activity in the modem world. They come in all sizes, shapes, and materials. They go by such names as spur, helical, bevel, hypoid, worm, skew, internal, external, epicycUc, and so on. 

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