Design of two-stage cylindrical gearbox

Second Build Stage

The purpose of the second stage of configuration is constructive registration of gear wheels, cogwheels, shafts, the case and some other details, and also preparation of necessary data for calculations on durability of shafts.

We will take the following procedure for performing this stage of work.

We design the designs of gears and gears according to the sizes found earlier.

Choice of lubricant grade

Lubrication of gear and worm gears and bearings is used to protect against corrosion, reduce friction coefficient, reduce wear, remove heat and wear products from friction surfaces, reduce noise and vibrations.

The lubrication method for general purpose reducers uses continuous lubrication with liquid oil by a crankcase method (dipping). This method is used for gears at circumferential speeds from 0.3 to 12.5 m/s.

The choice of oil grade depends on the value of the calculated contact stress in the teeth, and the actual circumferential speed of the wheels,. Oil grade is selected according to Table 10.29 - Recommended grades of lubricating oils for gears (GOST 17479-87). Oil grade I-G-S-68 (industrial oil for hydraulic systems with antioxidant, anticorrosive and anti-wear additives, with kinematic viscosity at 40 0 С 61 - 75 mm2/s.

The level of oil in the gearbox housing is controlled by various oil indicators. In this case, we are dealing with the most common iron oil indicator, since it is convenient for inspection; its design is simple and reliable enough.

During operation of gears, oil is gradually contaminated with wear products of gear parts. Over time, it ages, its properties deteriorate. Therefore, the oil poured into the gearbox housing is periodically changed. For this purpose, a drain hole is provided in the housing, which is closed by a plug with a cylindrical thread .

During long-term operation due to heating of oil and air, the pressure inside the housing increases. This leads to oil leaking through seals and joints. To avoid this, the internal cavity of the housing is communicated with the external environment by installation at its upper points of the perfume .