Thread Chain - Cycle98 - Siemens SINUMERIK 840D sl Operating Manual

Programming a cycle
4.5 Rotate
4.5.7

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.
Approach/retraction
1. Approach of the starting point determined in the cycle at the beginning of the run-in path
2. Infeed for roughing according to the defined infeed type.
3. Thread cutting is repeated according to the programmed number of roughing cuts.
4. The finishing allowance is removed in the following step with G33.
5. This cut is repeated according to the number of noncuts.
6. The whole sequence of motions is repeated for each further thread.
Procedure for thread chain
200
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.
for the first thread with G0
1. Select the part program to be edited in the "Program manager"
operating area.
2. Press the "Open" softkey or the "INPUT" key to edit the part program
in the editor.
Operating Manual, 01/2008, 6FC5398-7AP10-0BA0
HMI sl Turning