Fanuc America Corporation is expanding the availability of its arbitrary speed threading function, making it available for the 0i-TD and 0i Mate-TD CNCs it supplies for new turning machines. The function was previously introduced for the Fanuc Series 30i-B and 30i-A CNCs.
Arbitrary speed threading allows operators to adjust the spindle speed during thread cutting to control chatter. Also, it establishes quick rethreading functionality, and the ability to repair existing threads. According to Fanuc, these capabilities make arbitrary speed threading a valuable option for pipe and fitting thread maintenance in oil-and-gas industry machining.
The CNC developer added that arbitrary speed threading allows machine operators to adjust the spindle speed during a threading cycle to eliminate vibration and chatter. This is a valuable feature during thread repair because chatter is more likely to occur with the small amounts of material typically being removed.
Without arbitrary speed threading, the spindle speed override is inhibited during threading, to prevent damaging the part, as a change in thread lead would occur.
With arbitrary speed threading, the cutting tool remains coordinated with the spindle speed at all times during threading to produce the programmed lead.
Also, arbitrary speed threading provides machine operators with an ability to pick up and repair an existing thread, making it fast to set up, easy to use and quick to reproduce original threads. The process of repairing threads can be simplified further for operators by using Fanuc’s Manual Guide i conversational programming. Even with no G-code understanding,
The operator needs no understanding of G-code programming: graphical screens offer a straightforward approach to generating a suitable thread-repair program.
Arbitrary speed threading can be used with constant lead threading, threading cycle and multiple threading cycles. In addition to repetitive machining, the same thread shape can be machined even if the spindle speed is changed between roughing and finishing passes. (Cs contour control is required for this function.)
Arbitrary speed threading automates the rethreading process that used to be a manual process requiring a very high level of programming skill. This is seen increasing productivity for the oil-and-gas industry, wherein threading large-diameter or long workpieces and pipe rethreading or repair is common.