A spare part, spare, service part, repair part, or replacement part, is an interchangeable part that is kept in an inventory and used for the repair or replacement of failed units. Spare parts are an important feature of logistics engineering and supply chain management, often comprising dedicated spare parts management systems.
In logistics, spare parts can be broadly classified into two groups, repairables and consumables. Economically, there is a tradeoff between the cost of ordering a replacement part and the cost of repairing a failed part. When the cost of repair becomes a significant percentage of the cost of replacement, it becomes economically favorable to simply order a replacement part. In such cases, the part is said to be "beyond economic repair" (BER), and the percentage associated with this threshold is known as the BER rate. Analysis of economic tradeoffs is formally evaluated using Level of Repair Analysis (LORA).
Capital spares are spare parts which, although acknowledged to have a long life or a small chance of failure, would cause a long shutdown of equipment because it would take a long time to get a replacement for them.
Because of its self hardening properties, manganese steel has been used in the mining industry for many years – cement mixers, rock crushers, crawler treads for tractors, elevator and shovel buckets – as well as in the rail industry (switches and crossings) and other high impact environments.