The standard provides tables and graphs for thermal resistance (Rth) based on:
From Table 3 in ISO TR 14179-2 (heat dissipation for a cast iron housing of 0.8 m² surface area):
Not every engineer needs to perform the calculations manually. Many gear sizing software packages (like KISSsoft, MITCalc, or Romax) integrate ISO TR 14179-2. However, you still need to know the input parameters:
| Parameter | Description | Why it matters | | :--- | :--- | :--- | | Ambient temperature | Temperature around gearbox | Lower ambient = more thermal capacity | | Altitude | Above sea level | Reduced air density reduces cooling | | Type of lubrication | Splash, forced, or oil-mist | Affects churning losses | | Housing design | Cast iron vs. aluminum | Aluminum dissipates heat better | | Service factor | Duty cycle (continuous vs. intermittent) | Intermittent duty allows peak overload | iso tr 14179-2 pdf
The PDF contains detailed annexes with correction factors for unusual conditions (e.g., dusty environments, high humidity).
ISO/TR 14179-2 is a highly technical, essential resource for advanced gearbox design. It moves beyond simple efficiency estimates and provides a physics-based model for thermal management. While the data has largely been migrated into the main ISO 6336 series, the TR version remains a valuable standalone reference for understanding the why behind thermal ratings.
Rating: 8/10 (Essential for specialists, but casual users may find the math dense and the content slightly redundant with the current ISO 6336-2). The standard provides tables and graphs for thermal
ISO TR 14179-2 is a Technical Report titled: "Gears – Thermal capacity – Part 2: Thermal load-carrying capacity."
It is the companion document to ISO TR 14179-1, which deals with thermal capacity based on oil temperature. While Part 1 provides the basic calculation model, Part 2 specifies the thermal load-carrying capacity of gear units operating under specific conditions.
A: Contact ISO or your national standards body. Some allow student discounts (typically 20-30% off). Never download from torrent sites – the 2001 draft is obsolete. ISO/TR 14179-2 is a highly technical, essential resource
This is the core value proposition of the document. It outlines two main scenarios:
A: No. This report is for steel gear drives with continuous lubrication. Plastic gears have entirely different thermal properties.