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INNOVATIVE TECHNOLOGY
                                                           Increasing the

 WWX400 - INDEXABLE MILLING CUTTERS

 Mitsubishi Materials has added a versatile indexable      productivity of drilling
 insert milling cutter to its extensive range of high      of the helicopter
 performance tools. The new WWX400 is a series of
 true 90º corner milling cutters for face, shoulder and
 copying applications. Featuring economical double-        propellers made from
 sided trigon inserts with 6 cutting edges, WWX400 has
 been designed to meet all the needs of the modern         high-strength laminated
 metal cutting industry.                                   polymer composites

 Precision and reliability
 The innovative and accurate geometry of the insert      High-strength  laminated  polymer
 pocket, together with precise locating of the inserts   composites (HLPC) reinforced with titanium
 on the tool body, ensures that a true 90º wall can
 be machined on components. In most cases, this   are used in the design of the rotor blades
    and tail rotor blades of helicopters. The butt parts of the blades, intended for attachment to
 eliminates the need for secondary finishing operations,
 thereby saving valuable production time and costs.   the  engine  rotor,  are  made  by  spiral  winding of  glass-carbon  hybrid  fabric,  which is a  tape
 WWX400 cutters can perform at high feed rates to   consisting of alternating layers of 0.01 ... 0.15 mm thick carbon tow and glass rod. The layers
 ensure usability and efficiency across a wide choice   Furthermore, a high maximum depth of cut of up to   are impregnated with an epoxy molten binder.
 of applications. The body features four contact faces   8.2mm enables efficient shoulder milling capabilities.      To increase the strength of the butt part
 inside the insert pocket, plus the use of a large screw,   In order to meet component surface finish expectations,   of the blade, it is reinforced with multilayer
 that provides high insert clamping strength and stability   the bottom of all inserts feature a large radius geometry   packages consisting of titanium foil 0.1 mm
 without compromising accuracy. This means it can be   that acts like a traditional wiper.  thick and a unidirectional fiberglass prepreg
 used for semi-roughing as well finishing operations.           (Fig. 1).  The  thickness  of  such  a  winding,
 To further enhance usability and dependability, each   Three different chipbreakers are available, the L, M   which has a D-shaped section, is 50 mm, the
 body has internal through coolant channels that exit   and R breakers for light, medium and rough machining   width of the free space a is 20 mm. In the
 to supply high pressure cutting fluid directly at each   respectively. These can be matched with an extensive   parts  from  the  HLPC obtained  in this way,
 insert.  selection of 8 different coated and uncoated carbide   the holes necessary for fixing the blades are
 grades, providing choices that ensure the ideal                processed. Typical defects when drilling holes

 Innovative and economical inserts  combination can be chosen to effectively machine a   in  parts  made  of  HLPC  are  delamination  of
 The unique carbide inserts feature 6 usable cutting   wide range of materials.  the outer winding from fabric at the inlet and
 edges that offer lower costs and excellent process             outlet of the drill (Fig. 2) and delamination
 reliability thanks to a negative seating geometry but    Sizes  Fig. 1. Winding design: 1 - reinforcement package; 2 - free   of  the  reinforcement  package  (Fig.  3).  The
    space.
 provide a positive sharp cutting action. This generates   The WWX400 arbor type face mill cutters are available   appearance  of  such  delaminations  leads  to
 low cutting forces and together with an increase in   from Ø50 - Ø250 in coarse, fine and extra fine pitch   a decrease in the structural strength of the
 insert thickness compared to conventional types, also   geometries. Shank types from Ø50 - Ø80 can also be   HLPC blades.
 provides excellent resistance to breakage.   specially ordered.












     Fig.2. Delamination at the drill entry.
            One of the ways to increase the productivity
    of flawless drilling of holes in HLPC parts is to
    increase the rigidity of the composite layers. For
    this,  the  free  space  of  the  blanks  (see  Fig.  1)
    was filled with fillers (Fig. 4): a) bars made of
 90° WALL MACHINING  aluminum alloy D16T; b) a hard compound used
 UP TO 8.2 MM   MULTIPLE INSERT   for milling monolithic work pieces made of heat-  Fig.3. Layering h of the amplification package.
 DEPTH OF CUT  CLAMPING FACES   resistant alloys.
 FOR ACCURACY AND
 RELIABILITY     The holes were machined with a drill made of high-speed steel R6M5 with a diameter of
 LOW CUTTING FORCES  10 mm to a depth of 20 mm at speeds V = 15 ... 60 m / min and feed rates of 0.2 ... 1.6 mm
    / rev.
            The dimensions of the delamination h were measured in the reinforcement package (Fig.
    5) and in the outer winding of the HLPC (Fig. 6). The magnitude of delamination Δ in the outer
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