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PROFESSIONAL ADVICE                                                                      PROFESSIONAL ADVICE

 on the surface of the sleeve is proportional to the time t of the heat source with a power of q   axis of the sleeve (see Fig. 2).
 (W / m2) to this section, to this site.     Traditionally,  the  workpiece
    Depending on the ratio of the length and stroke of the hone, three heating schemes for   is cooled  by  supplying coolant  to   overlapping
 the workpiece are possible (see Fig. 1):  the  processing zone.  To  cool the   matching
 1) the processing areas in the extreme positions of the hone do not overlap, and a ‘‘gap‘‘is   outer  surface  of  the  sleeve in the   gap
 obtained between the extreme positions of the distributed source (2), see Fig. 1a;  cuff,  deep  grooves  are  performed
 2) the processing areas in the extreme   so that  the  coolant entering  the
 positions of the hone overlap (see Fig.   Table 1. Processing modes and heat input into the   cavity can  also wash  the  outer  wall
 1b),  the  distributed  source  forms  a   workpiece.  of the sleeve. Meanwhile, the cooling
 ‘‘overlap‘‘ (zone 3);     rate  can  be  increased by  supplying
 3) the source  in extreme  positions is   Honing Type №  Рок, Н рб, кPа W, m/с Р, кWe Q, kWe  coolant  through  the  cuff.  To  do
 ‘‘in  contact‘‘,  i.e. the overlap  zone  (3)   Polishing  1  1536  400  0,67  1,0  0,62  this, it is enough  to compress  the
 degenerates to a point.  2  1920  500  0,83  1,6  0,99  cuff  with  through  holes  in  the  wall
    The  graphs  in  fig.  1  reflect  the   3  2304  600  1,00  2,3  1,48  using coolant. The simulation of the
 speed  of  the  extreme  points of  the   heating  and  cooling process,  the
 distributed source  in  a  given  scale,   Clean  4  2304  600  0,83  1,9  1,19  calculation  of  the  temperature  field
 corresponding to the left (dashed line)   5  3072  800  1,00  3,1  1,97  of the liner were performed using the   Fig. 2. Change in heat flux density along the axis of the sleeve
 and right (solid line) end of the hone.   6  3840  1000  1,17  4,5  2,91  Flo application of the SolidWorks package. The FloWorks SolidWorks application uses the finite
 In Fig. 1, the origin coincides with the   volume method to solve the problems of fluid dynamics and heat transfer. The sleeve heat
 middle section  of  the  sleeve,  and  the   Preliminary 7  3840  1000  1,00  3,8  2,46  transfer model takes into account the following physical effects: the movement of fluid in the
 X axis,  oriented  along  the  axis  of  the   Draft  8  5760  1500  1,17  6,7  4,37  channels formed by the sleeve wall and the rubber sleeve holding the sleeve (see Fig. 3),
 sleeve, reflects the linear size reduced   semi-clean  9  7680  2000  1,33  10,2  6,66  convective heat transfer of the sleeve with the liquid washing its outer surface, heat transfer
 to scale, S is the hone course, A is the   between the sleeve and the sleeve, and radiation heat transfer. When constructing the design
 hone overrun, LГ and LХ are the length   scheme, the opportunity to reduce the dimension of the model due to the symmetry of the
 of  the  sleeve  and  the  length  of   solution was used. The calculation results (see Fig. 3) are the streamlines and the velocity
 the hone, respectively.  fields of the fluid moving in the channels of the cooling jacket, the temperature fields of the
    The duration of  the  heat   fluid and solids. Figure 3a shows the velocity field of the fluid (3) moving in the channels of the
 source on the site dF is determined   cooling jacket, which is formed by the wall of the sleeve (1) and the cuff (2). The calculation
 by the  heating pattern  of  the   was performed inside the computational area (4) with symmetric boundary conditions. Figure
 workpiece  and  the  X coordinate   3b shows the temperature field of the liner in the axial section of the computational domain for
 of the site, because the average   the overlapping heating circuit.
 velocity and active length of the      The nature of the thermal deformations
 source  LA,  passing over  the  site   of  the  liner obtained for  the  overlapping
 dF, depend on the latter.  scheme and processing mode No. 9 from table
    From  figure  1a  we  can   Fig. 1. The location of the heat source.  b  1  for  different  cooling  options  is  shown  in
 conclude  that  for  each  scheme   1 - sleeve, 2 - hon.  Figure 4. The calculation was performed using
 the equality is true:  a - the heat source in extreme positions does not form a zone of overlap,  the  SolidWorks  Simulation  application  that
 b - in extreme positions, the heat source forms an overlap zone 3.
    implements finite element calculations.
            Deformations  are  obtained  as  a  result
    of  finite  element  modeling  based  on  the
    specialized  Simulation  application of  the
    SolidWorks  package.  The  main  results  of  the
    calculations performed  for  processing modes
    No. 2 and No. 9 from table 1 for a traditional
    cooling circuit (TCC) and with cooling through a
 or  cuff are shown in table 2. The heating patterns
    in table 2 are indicated:
            ● circuit with a gap - R,
            ● scheme with matching - C,
    An exception is the overlap zone of the second circuit, in which the source heat is present      ● scheme with overlapping - P.
 all the time.     The  obtained  values  of  temperatures
    Calculating the source action time as the ratio of LA to the average hone speed V in an   and  geometry  errors are  in good agreement
 arbitrary portion of the sleeve [x0; xφ]:  with the  results of  [1,  2,  3,  4]  and  GOST  R   Fig. 3. The results of the simulation.
    53809-2010.  Thus,  semi-finishing  processing                  a - movement of the coolant in the cooling channels, b -
    leads to heating of the workpiece to 87 ° C,                                          temperature field of the sleeve.
    and polishing to 37 ° C.
            An  analysis  of  the  results  shows  that
 it is possible to plot the distribution of the thermal power of a quasi-stationary source along the   large values of the temperature of the sleeve


 32  Stanochniy park                                                                            Stanochniy park       33
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