What are the differences in the performance of graphite copper sleeves at different temperatures?

Graphite copper sleeves generally have high temperature resistance and a wide temperature range. Specifically, graphite copper sleeves can remain stable in high temperature environments and are not easy to deform. The temperature range is usually above 1000℃, and the highest temperature resistance of some high-quality graphite copper sleeves can even reach 1500℃. This feature enables graphite copper sleeves to maintain good working conditions under high temperature conditions. The performance of graphite copper sleeves will vary at different temperatures, which mainly depends on the characteristics of the copper alloy matrix and graphite lubricant.

Low temperature environment (below room temperature)

• At low temperatures, many lubricating oils and greases will become more viscous and may even solidify, resulting in a decrease in lubrication effect. However, the self-lubricating properties of graphite copper sleeves are still effective in this case because graphite lubricants do not rely on liquid lubricants.
• Low temperatures may increase the brittleness of metal materials, but this generally does not have a significant effect on the overall performance of graphite copper sleeves unless the temperature is extremely low.
• In this temperature range, the interaction between the copper alloy matrix and the graphite lubricant provides good lubrication and wear resistance. Graphite copper sleeves can withstand normal working loads, and the friction coefficient and wear rate are at a low level.

Medium temperature environment (close to room temperature to 250~350℃)

• As the temperature increases, the copper alloy matrix may become softer, which may slightly increase friction and wear. However, the lubrication effect of graphite is still effective and can help reduce these problems.
• Increased temperature may improve the lubrication performance of graphite because graphite is easier to transfer and form a lubricating film on the contact surface at high temperatures.
• In this temperature range (250~350℃), the graphite copper sleeve can still maintain sufficient strength and lubrication performance, but the thermal expansion coefficient should be considered, and the fit clearance between the graphite copper sleeve and the shaft should be appropriately increased to prevent the occurrence of locking.

High temperature environment (above 350℃)

• At high temperatures above 350℃, the strength and hardness of the copper alloy matrix will decrease, which may affect the structural integrity and load-bearing capacity of the graphite copper sleeve.
• High temperature may cause the performance of graphite lubricants to deteriorate because graphite begins to oxidize at around 400℃, which may reduce its lubrication effect.
• At extremely high temperatures, graphite copper sleeves may require special design or material selection to ensure their performance and safety.

Due to their excellent temperature resistance and self-lubricating properties, graphite copper sleeves are widely used in various occasions that need to withstand high temperatures and friction and wear. For example, graphite copper sleeves play an important role in pumps, valves, agitators and other equipment in food processing, oil refining, chemical and other industries. In addition, graphite copper sleeves can also provide reliable lubrication and support in occasions that need to withstand heavy loads, high speeds or impact loads.

Zhejiang Mingxu Machinery Manufacturing Co., Ltd. mainly deals in graphite copper sleeves, copper plates, gaskets, guide rails, etc., and supports customization according to drawings. Welcome to inquire: [email protected]