a metalcutting machine for cutting threads in nuts by means of special elongated machine taps. Nut-thread cutters are generally of the single- and multiple-spindle type, operating in a nonautomatic, semiautomatic, or automatic cycle. Nut-thread cutters are also manufactured in special versions, for example, for threading spark plug nuts. Nut-thread cutters with a nonautomatic operating cycle usually have one spindle. The machined nuts are threaded onto the tap. After filling up an entire rod, the tap is removed manually and the nuts are released. Such machines are used to thread nuts ranging from 1.5 to 20 mm in diameter. Nut-cutting machines that operate with semiautomatic or automatic cycles are manufactured with two, four, six, and eight spindles. Machine capacities range from 525 to 3,000 nuts per hour, depending on the diameter of the thread to be cut (from 16 to 36 mm). The taps installed on these nut-thread cutters have a 150 mm working part.
V. V. DANILEVSKII