5.1.1 Use of Steel Chains in High Temperatures
When heat-treated chains are run in temperatures higher than their tempering limits, the following problems may occur:
- Increased wear due to decreased hardness.
- Improper lubrication due to lubricant deterioration or carbonization.
- Stiff joints and increased wear due to oxide scale formation.
- Decrease in strength.
To prevent lubricant deterioration at high temperatures, use a special lubricant. Table 5.1 shows the transmission capability of power transmission roller chains with high-temperature lubricant. Check the manufacturer's catalog for additional information.
When chains are used in temperatures above 250°C, pay special attention to the composition and heat-treatment of the chain. The most popular type of chain for high temperature is SS specification, which is made of 304 stainless steel, and has a maximum working temperature of 650°C at low speeds. However, to maintain an adequate safety margin at a high temperature like this, we suggest you use NS-specification chain. NS chain is made of 316 stainless steel, which contains molybdenum and less carbon. NS specification has worked at low speed in environments up to 700°C.
If your operation runs at temperatures higher than 400°C, consult the manufacturer before making your chain selection. Production methods and materials may be specially adapted for your application.
|Up to 150°C||MAX|
|150°C to 200°C||MAX × 3/4|
|200°C to 250°C||MAX × 1/2|
|Over 250°C||Out of Use|
1MAX = Maximum allowable load as shown in the manufacture's catalog