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Circular pocket milling (cycle 5) – HEIDENHAIN iTNC 530 (340 420) User Manual

Page 301

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HEIDENHAIN iTNC 530

273

8.4 Cy

cles f

o

r Milling P

o

c

k

ets, St

uds and Slots

CIRCULAR POCKET MILLING (Cycle 5)

1

The tool penetrates the workpiece at the starting position (pocket
center) and advances to the first plunging depth.

2

The tool subsequently follows a spiral path at the feed rate F - see
figure at right. For calculating the stepover factor k, see Cycle 4
POCKET MILLING.see “POCKET MILLING (Cycle 4),” page 267

3

This process is repeated until the depth is reached.

4

At the end of the cycle, the TNC retracts the tool to the starting
position.

U

U

U

U

Set-up clearance

1

(incremental value): Distance

between tool tip (at starting position) and workpiece
surface

U

U

U

U

Milling depth

2

: Distance between workpiece

surface and bottom of pocket

U

U

U

U

Plunging depth

3

(incremental value): Infeed per cut

The TNC will go to depth in one movement if:

n

the plunging depth is equal to the depth

n

the plunging depth is greater than the depth

X

Y

X

Z

11

12

13

Before programming, note the following:

This cycle requires a center-cut end mill (ISO 1641), or pilot
drilling at the pocket center.

Pre-position over the pocket center with radius
compensation R0.

Program a positioning block for the starting point in the tool
axis (set-up clearance above the workpiece surface).

The algebraic sign for the cycle parameter DEPTH
determines the working direction. If you program DEPTH =
0, the cycle will not be executed.