Page 18 - MMI_MarApr 2021 (high-singles)
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Tooling for honing is selected based on application requirements. Source: Sunnen
Honing can questions about it. Here are five heavy equipment, agricultur- 2 What unfavorable bore
correct of the most common: al machinery, and aerospace
errors flight and landing gear control conditions can honing
caused by 1 What applications systems, are typically honed. remedy?
previous This provides tight clearanc- Quite a number, including bore
machining commonly call for honing? es between the valve body diameter size, bellmouth, wav-
processes Engine cylinders and cylinder and spool to reduce the sealing iness, taper, rainbow, barrel
because it sleeves require honing for prop- area required. Honing also cre- shape, reamer chatter, boring
does not er piston ring sealing. Diesel ates the proper surface finish for marks and out-of-round holes.
require engine fuel system components the oil seals, which, combined The improved shape of the bore
chucking or are often honed because hon- with reduced clearances, pre- after honing almost always re-
alignment ing enables tighter control of vents oil leaks. sults in mating components
and is the clearance between the bore Honing also improves the bore operating more quietly and effi-
indifferent and its mating part. The result- diameter size and surface finish ciently. Honing can correct er-
to bore ing higher fuel system pressure of gun barrels prior to the rifling rors caused by previous machin-
length. means more fuel is atomized and operation. This ensures uniform ing processes because it does not
less unspent fuel is used, result- rifling for a better shot. The pro- require chucking or alignment
ing in improved fuel efficiency cess is also useful for gears, small and is indifferent to bore length.
and engine performance as well engines, brake drums, compres- Other machining processes, such
as lower carbon emissions. sors, oil and gas flow meter tub- as grinding and boring, might
Cartridge valves, used in hy- ing, and many other applications. fracture the metal’s subsurface to
draulic applications such as a depth of 0.002 inch. In addition,
tool wear can cause work-hard-
ening of the bore surface during
machining. Honing is a gentler
process, generating very little
heat so as not to distort the bore.
Source: Sunnen 3 What types of
Like other machining operations, honing lends itself to robotic automation for high-volume surface finishes can
applications. honing achieve?
Surface finish, texture and ap-
pearance can be precisely con-
trolled. The angle of the cross-
hatch pattern can be adjusted by
varying the spindle speed and
stroke speed of the honing tool.
Some applications call for a steep
crosshatch angle in the bore,
while others require a shallow
18 | March-April 2021 Modern Manufacturing India
