Gullco KBM-28 - Manual (Page 27)

23
BEVELLING FLAME CUT STEEL PLATES
Flame cut steel plates may be work hardened and have slag on the edges. Flame cut mild steel
can be bevelled with the KBM
®
-28, but all slag should first be removed from the edge to be
bevelled. Flame cut high tensile steel, however, may be difficult to bevel with the KBM
®
-28. This
material is subject to hardening by rapid cooling after flame cutting. Check to see if the material is
capable of being machined before attempting to bevel it with the KBM
®
-28.
BEVELLING OF TOUGHER MATERIALS
Because materials such as stainless steel and high grade steels tend to be tougher and generally
posses a higher tensile strength than mild steels, it is more difficult to bevel these materials with the
KBM
®
-28 machine.
The amount of metal to be removed in one pass by the KBM
®
-28, is adjusted by the Slide Base
mechanism (as previously described in the manual), to give a bevel cut setting suited to the tensile
strength of the material. The maximum recommended bevel widths for various tensile strengths at
various degrees of bevel angles are shown in the table located earlier in this manual, under a
section entitled "Bevelling Capacity".
The following are recommendations for bevelling high tensile plate;
1. Bevelling tougher materials should always be performed on the conservative side in terms of
smaller bevel cuts and increased number of passes.
2. Always use a sharp cutter. The need for re-grinding/replacing cutters depends on the
amount of use and work involved, however, it is always advisable to closely monitor the
cutter, as worn cutters may produce detrimental factors such as loss of performance due to
feeding problems, poor quality and consistency of bevel as well as the possibility that the
cutter might break before it can be re-ground.
3. When a heavy work load is involved, time and operating costs can be reduced by using two
or more KBM
®
-28 machines, each adjusted to provide a different bevel depth for multi pass
bevelling, allowing the operator/operators to use one machine for each pass without having
to make adjustments to the machine in-between.
It is generally agreed throughout the steel fabrication industry that machining bevels on tough,
heavy, steel plates such as stainless steel, is both difficult and costly, as is plasma cutting, which
requires additional hand grinding. If properly planned and carefully performed, bevelling tough plate
with the Gullco KBM
®
-28 Portable Plate Edge Bevelling machine remains the most economical
method in terms of total cost.