Description
This paper will discuss the value of the twist test as a process control tool and as a test to determine copper rod surface quality. The changes in twist test equipment, procedures and the evaluation of test results over the last 20 years at Magma Copper Company will be discussed. The discussion will include the evolution of the twist test starting with the 10 turn forward and 10 turn reverse test, improved testing equipment, and several variations to the standard 10 X 10 twist test such as the 3-die twist test and the 35 turn twist test on break down wire.