You can question Gemini Enterprise about design standards or existing product specifications, drawing on integrated enterprise data.
Example prompt
In the chat box, enter a prompt such as the following:
What is the acceptable tolerance for the diameter of [COMPONENT]?
Example output
In response to this prompt, Gemini Enterprise produces output similar to the following:
The acceptable tolerance for a 25 mm steel drive shaft depends entirely on its application and the type of "fit" required with its mating components, such as bearings or gears. There is no single universal tolerance. Instead, engineers use a standardized system, ISO 286, to define these tolerances.
This system specifies different "fits," which are categorized into three main types:
- Clearance Fits: The shaft is always smaller than the hole, allowing for rotation or sliding.
- Transition Fits: There can be either a small clearance or a slight interference, used for precise location where disassembly might be needed.
- Interference Fits: The shaft is intentionally larger than the hole, creating a solid, press-fit assembly that transmits torque.
Factors That Determine the Right Tolerance
Several key factors must be considered to select the appropriate tolerance for a drive shaft:
- Mating Components: The primary factor is what the shaft connects to. For instance, the fit for a ball bearing will be different from that for a gear or a pulley.
- Operating Conditions: High speeds, heavy loads, and significant temperature variations all demand tighter and more specific tolerances to prevent failure.
- Rotational Component: As a general rule, the part that rotates (usually the shaft) requires a tighter, interference fit with its mating component to prevent slipping or "creep."
- Material: The material of both the shaft and the housing is important. For example, an aluminum housing expands more with heat than a steel one and may require a tighter initial fit.
Common ISO Tolerances for a 25 mm Shaft
For a nominal 25 mm diameter shaft, here are some common ISO tolerance "classes" and their corresponding dimensions. These classes are designated by a letter (which sets the tolerance position relative to the nominal size) and a number (which indicates the tolerance magnitude).
Fit Type ISO Class Upper Limit (mm) Lower Limit (mm) Application Examples Clearance (Loose) h11 25.000 24.870 Used where high accuracy is not needed, suitable for large temperature variations. Clearance (Running) g6 24.993 24.980 For sliding parts and guiding shafts that need to move and turn freely with high accuracy. Clearance (Sliding) ...