Siemens SINUMERIK 840D sl Function Manual page 1433

Hide thumbs Also See for SINUMERIK 840D sl:

Table of Contents

Calculation of intersection

When the intersections in blocks with variable compensation value are calculated, the

intersection of the offset curves (tool paths) is always calculated based on the assumption that

the compensation value is constant.

If the block with the variable compensation value is the first of the two blocks to be examined

in the direction of travel, then the compensation value at the block end is used for the

calculation; the compensation value at the block start is used otherwise.

Figure 18-33 Intersection calculation with variable compensation value

Restrictions

If during machining on the inside of the circle the compensation radius becomes geater than

the programmed circle radius, then the machining is rejected with the following alarm:

Alarm 10758 "Curvature radius with variable compensation value too small"

Maintain stability of closed contour

If a radius of two circles is increased slightly, a third block may be necessary in order to maintain

the stability of the closed contour. This is the case if two adjacent blocks, which represent two

possible intersection points for a closed contour, are skipped due to the compensation.

A stable closed contour can be achieved by choosing the first intersection point instead of the

SD42496 $SC_CUTCOM_CLSD_CONT ≠ 0 (response of TRC for closed contour).

In that case, the second intersection point is always reached, even if the block is skipped. A

third block is then not required.

Basic Functions

Function Manual, 01/2015, 6FC5397-0BP40-5BA2

18.5 Tool radius compensation 2D (TRC)

W1: Tool offset

Sinumerik 828d Sinumerik 840de sl