No. 4, 1998 - Tribology in Industry

UDK 52i.821.015.62
S. SEKT]LIC
Tribological proces s es
ira The Cutting Zone
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The paper presents the conternporary views ort tibological
that'
phettometta
the physical
in the
nature
metal
of
cutting
thi pheriomt',ro
processes. Besides
iyro*, iitntijpii,ti,u'i, production is pointed out.
Kqwords: Tibologt,curfiilg tool cuttittg
1. GEI{ERAL
Tiibrjlogy has enormous importance in production processes,
especially in metal machining. In this p."r"nto_
tion we shali primarily deal with triilological processes
that are accompanying metal cutting.
'iiibolcgical processes in cutting conditions are charac_
terized by contact surfaces, streis and temperature field
distributions, as well as fast appearance of new surf.aces,
rvhat all makes these concJitions specific.
In rlepth knowledge of tribological processes in general,
and especiaily in the cutting p.o."rr, enables achievenent
of optimum solutions both in technical end econo_
mical sense. Here ii primarily reterred to introduction of
the r:ewpr'cesses, but also the special materials, b'th for
tools and machined pieces (e.g. hardly machined mate_
rials that are causing problems duringtheir machining).
By arraly5l5 of machining costs for one operation U6,we
can state that they consist of Iabor costs R, costs rerated
to tool amortizatioir A and machine costs M, i.e.,
f,,'hef e:
Uo=R+A+M+SHp
^f,
tv! -
,R = tt.k7.tk
cu'P
F-4.100.60
A=A1+.4r+A,
t
A,=lt'k,.t..4
1 I tT
t
Ar= kr.tr.-l
Fro.t. tlr Siti,a St. Sekulit, rtipt, eng.
!;.ri
ti Lil s far I t : t ! us t n a l,S1,s t i t ns
i:'trt:rllty of Techtzical Sciences Univenity of Novi Sart
.L
"=''\r;
,cntr
17.-= "" -"'.'='
r io+1 T
5r,, _ e_$!r.c;rtt.!t
60
lo= tr+ ta+ tp+ tor+ t;
lo
lo= t;i;
Uo=E'B+t,
B = tpr trr* lpr* l,=66nry.
E = tt.k. .--"
1F .11.100.60
G = kr.tr-:i
to- t
/ c)
kr.N,
71= I 4.'.i.-.---1.
kt'N,
l, -':'-u- |
(. r)
ctt !
where:
k1; k2; kj are the gross salaries of the productive worker;
sharpener, expert worker (brigadier), respecti_
vely in din/min;
/k - comntanding time,
C,y - machine price;
p - amortization rate;
F - annual time fund;
ry - efficiency ratio;
A6 A5 A j - costs of replacement, sharpening and
amortization, respectively;
/, - main machine time;
/o- time for tool replacement per machined piece;
lr - auxiliary time;
to, = foJz - preparation/finishing time per machined
piece;
'inbelsgt,
irt iitdusity, Volume 20, No. 4,lg9g.
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