Title: Gears – Thermal capacity – Part 2: Thermal load-carrying capacity
Type: ISO Technical Report (TR) – not a full International Standard, but a supporting document providing explanatory or application guidance.
Part 2 provides empirical formulas for no-load losses (churning, windage, seal drag). These losses depend on: iso tr 14179-2 pdf
The report often details how to create a thermal network model. This involves treating the gearbox as a network of thermal resistances and nodes (housing, shafts, bearings, gears, oil, and ambient air) to calculate heat dissipation accurately.
Most gearbox designers obsess over tooth bending stress (ISO 6336) or pitting resistance. But the silent killer of gearboxes isn't stress—it's heat. Every year, millions of dollars are lost to lubricant coking, tooth scuffing, and oil seal failure caused by underestimated thermal loads. Title: Gears – Thermal capacity – Part 2:
Enter ISO TR 14179-2:2007 – the "Technical Report" that is anything but boring. While Part 1 of the standard gives you the thermal balance equations, Part 2 is the secret weapon: a massive library of thermal dissipation data for real-world gearboxes.
Title: Gears — Thermal capacity — Part 2: Thermal load-carrying capacity Status: Technical Report (TR) Publication Date: Originally 2001 (later integrated into ISO 6336-2 in 2006, but the TR remains a key reference for detailed calculations). This involves treating the gearbox as a network
A: No. It is informative. However, EN standards often reference it for declaring thermal ratings.
The document guides the engineer through solving the heat balance equation: $$P_V = Q_air + Q_oil + Q_rad$$ It helps determine the "Thermal Rating" of the gearbox—the horsepower limit at which the gearbox stabilizes at a safe operating temperature.
Let’s walk through a typical use case for the ISO TR 14179-2 pdf.
Scenario: You need to select a gearbox for a conveyor system. Motor power = 45 kW, output speed = 30 RPM, ambient temperature = 40°C, altitude = 1500m.