Elongated Hole - Longhole - Siemens SINUMERIK 840D sl Operating Manual

Programming a cycle
4.7 Milling
Parameter
UXY
Positioning
1) Parameter description refers to plane G17; plane selection G18 or G19 possible in selection field
(MD 52005: $MCS_DISP_PLANE_MILL)!
4.7.9

Elongated hole - LONGHOLE

Function
Use the "Elongated hole" cycle to machine elongated holes arranged on a circle. The
longitudinal axis of the elongated hole is aligned radially.
In contrast to the groove, the width of the elongated hole is determined by the tool diameter.
Internally in the cycle, an optimum traversing path of the tool is determined, ruling out
unnecessary idle passes. If several depth infeeds are required to machine an elongated
hole, the infeed is carried out alternately at the end points. The path to be traversed in the
plane along the longitudinal axis of the elongated hole changes its direction after each
infeed. The cycle searches for the shortest path when changing to the next elongated hole.
NOTICE
The cycle requires a milling cutter with a "face tooth cutting over center" (DIN 844).
Approach/retraction
1. Using G0, the starting position for the cycle is approached. In both axes of the current
2. Each elongated hole is milled in a reciprocating motion. The machining in the plane is
3. Retraction to the retraction plane using G0 and approach to the next elongated hole on
4. After the last elongated hole has been machined, the tool at the position reached last in
244
Description
Plane finishing allowance - (only for ∇, ∇∇∇, ∇ + ∇∇∇ and ∇∇∇ edge)
Positioning motion between the grooves:
Straight line:
•
Next position is approached linearly at rapid traverse.
Circular:
•
Next position is approached at the programmed feedrate FP along a circular
path.
plane, the closest end point of the first elongated hole to be machined is approached at
the level of the retraction plane in the tool axis and then lowered to the reference point
shifted by the amount of the safety clearance.
performed using G1 and the programmed feedrate. At each reversal point, the infeed to
the next machining depth calculated internally in the cycle is performed with G1 and the
feedrate, until the final depth is reached.
the shortest path.
the machining plane is moved with G0 to the retraction plane, and the cycle terminated.
Operating Manual, 01/2008, 6FC5398-7AP10-0BA0
Unit
mm
HMI sl Turning