Thread Chain (Cycle98) - Siemens SINUMERIK 840D Operating Manual

Parameters
8.4.7

Thread chain (CYCLE98)

Function
With this cycle, you can produce several concatenated cylindrical or tapered threads with a
constant pitch in longitudinal and face machining, all of which can have different thread
pitches.
There may be single or multiple threads. With multiple threads, the individual thread turns
are machined one after the other.
You define a right or left-hand thread by the direction of spindle rotation and the feed
direction.
The infeed is performed automatically with a constant infeed depth or constant cutting cross-
section.
● With a constant infeed depth, the cutting cross-section increases from cut to cut. The
● With a constant cutting cross-section, the cutting pressure remains constant over all
The feedrate override has no effect during traversing blocks with thread. The spindle
override must not be changed during the thread machining.
Milling
Operating Manual, 03/2010, 6FC5398-7CP20-1BA0
Description
DA Thread changeover depth (inc)
First machine all thread turns sequentially to thread changeover
depth DA, then machine all thread turns sequentially to depth 2 ·
DA, etc. until the final depth is reached.
DA = 0: Thread changeover depth is not taken into account, i.e.
finish machining each thread before starting the next thread.
Complete, or
Machining: 
from turn N1

N1 (1...4) start thread N1 = 1...N
only thread NX

NX (1...4) 1 from N threads
finishing allowance is machined in one cut after roughing.
A constant infeed depth can produce better cutting conditions at small thread depths.
roughing cuts and the infeed depth is reduced.
Programming technological functions (cycles)
8.4 Turning - only for G code programs
or
Unit
373