Kale and Kandhare book

1. TABLE: 1.1
PHYSICAL PROPERTIES OF COMMONLY USED MATERIALS
CP ImC
Kg'm
Ex 10
MPa
Gx 10
MPa
ax 10
nn/mmc
Matcrial
W/m "
K J c
0.45
1800
2710
25.2
ifagncsiun
Aluminium
Brass
Grcy cast Iron
Copper
Lead
Moncl Mctai
Steel C15
Steel C 35
Steel C 60
Pbospbet
Bronze
Nickel steel
4.5
7.25
0.3
35
0.334
0.285
1.69
G60
900-950
1150-1300
1083
327
1325
10
1490
0.27
G.376
0.5.4
0.45
2.67 173 24.0
12.6 4.91 18.7 8210
10.6
16.2
720
10.0
12.3
15.7
0.271
0.26
4.21 46
8
39.0
S
338
13-40
8820
7850
7840
783
0.45 28
26
. 8.
18.3
20.8
6.6
7.9
.32
0.3
0.3
054
G.45
14.0
43 11.1
20.6 to 43 11.1 to
8.9
4.21
1470
910-1040o
20.4 0.3
0.349
40 11.1 0.4
11.1 58 17.3 8160
20.0 7.72 0.291 40 11.1 TIS0 C45 1470
Where,
E Modulus of Elasticity
G Modulus ofRigidity
= Poissons ratio
K Thermal conductivity
=Coeffficicnt oflinearcxpansion
W Specific weight
Cp Spccific hcat
ImMeltingpoint
TABLE: 1.2
APPROXIMATE RELATIONSHIPS BETWEEN STRENGTHS
|Sr.
No
Matcrial S Scb Seb
S
Syt
Sea
Scb
Ses
Sch
Sus
Sut
Sut Sut Suc
Stcci
Cast iron
Non Ferrous Alloys
Sut
0.6-0.7 0.5-0.6 0.8-0.9 0.65 0.55
0.9
0.8
0.65 7.5
0.31
0.4
1.0
0.25-0.3S 0.7-1.0 0.16
where,
Syt = yicld stress in tension
Sut Ullimate tensile stress f matcrial
Scb Endurance limit in
reversed bend:n
Sca
Endurancclimitin aual lwading
Scs Endurancc limit in torsinal loadi
Sus =
Ullimalc strength in shear
Suc =Ullimate streng1h in
cmpressi

2. CHAPTER3
VALUES OF PERFORMANCE PARAMETERS
TABLE:3.
Compression Ratio (R)
Diesel Engine
TypcofEngine
S.No. Petrol Engine
R
ON R
Diesel engine with
open chambers
Swril Chamber
1 66-72 5.5 -7.0 14-17
2. 72-76 7.7-7.5 16-20
diesel cngines
3. 76-85 7.5-8.5 Pre - combustion
16.5-21
chamber dicsel engine
Super chargcd
diescl engine
85-100 8.5 10.5 11-17
Where
R =Compression ratio
ON =
Octanenumberof petrol fucl
TABLE:3.2
INDICA1ED MEAN EFFECTIVE PRESSURES (Pim)
S.No Type Pressure, MPa|
0.60 to1.40o
Four stroke petrol
engine
Four stroke diesel
1.
2 0.70 to 1.1
engine
Four stroke super
charged dieselchgine
3.
up to 2.2
TABLE:3.3
INDICATED THERMAL EFFICIENCY (7thi)
Type ofengine Thermal Efficiency (%
S.No.
1.
Petrol engine
Diesel engine
26
38-50
35
2.
TABLE:3.4
INDICATED SPECIFIC FUEL CONSUMPTiON (ISFCD
S.No.
Typc ofengine ISFC, kg/hr-kw
Pctrol engine
Dicsel cnginc
1.
0.24 0.32
0.17 0.23
2.

3. TABLE 3.5
MECHANICAL EFFICIENCY (n m)
Mechanical Efficicncy()
S.No. Tye of engine
70-90
Two/four
strokepetral engine
70-82
2. Four stroke diesel enginc
70-85
. Twostrokedicselengine
TABLE 3.6
RORE DIAMETER
Standard cylinder
bore, D,mm.
S.No. Type of engine Borc liam:ter
inmn
Pclrol engine for car -1000 30, 32, 36, 38, 40,42, 45,
Petrol enginefor bucks
Tractor diesel cnginc
50, 52, 56,58,60,63,68,70,75
80, 85, 90, 95, 100,105, 110,
1i5, 120,125,130, 140, 145
150, 160, 170, 180,190,200,210
2. 70-114
.
70-150
Automobile dieselengin 80-130
TABLE3.7
STROKE TO BORE RATIO (SD)
S.No. Type ofengine SD
1. Pctrol cngine 0.7 1.0
2. Diesel engine
0.9-1.2
3.
Tractor diesclengincs 1.1-1.3
TABLE 3.8
MEAN PISTON SPEED (Vpm)
S.No. Typc ol engine Mean Piston specd M/sec|
Pclrol cngine for car
Pctrol engine forbluck
Aulomobile dicsel engin¢
Tractor dicsel cnginc
12-15
9-12
2.
3.
6.5 - 12
5.5-105

4. TABLE:3.9
ENGINE PERFORMANCE RELATIONS
SNo. DESCRIPTION RELATIONS
Mcchanical Efñiciency, 7m ,% 7mPx100
1.
where P - brake power in KW
Pi-IndictedpowerinKW
PiPim LANIne XIoS
Pim actual meanindicatedelfective pressure, N/m*
(Ref. table 3.2 )
L StrokcLength, m
A Bore arca,m
Ni N/2, four stroke
- N, Two strukc
N Spced,RPS
ncno. olcylin:lers.
PimPimtX f 8
where
2. Actual Indicated Mean
cffective Pressure, Pim, N/m
f diagamfactor
=
0.94 to 0.98, for petrol engine
=
0.92 to0.95,for dicscl engine
Pimt-Thcoreticalindicatcd.
mean cffective pressurec,N/m
a)forpctrolcngine:
P(R)I1-R-]+Ps[1]-
Pimt
(-1) (R-1)
where
r adiabalicindex = 14
R Compressionratio (ReferT:3.1)
P1=Suctionpressure,N/m
P3- Maxaimumgaspressure,N/m =Pmax
b) ForDieselengine
P2= R'P1
Where,
P2 MaxGas pressure=Pmax
Pcutoffratio
PR(1-R)+ R'(p-1)]
T-1
Piont (R-1)
Indicated specific fuel ISFC= BSFC
m
consumption, ISFC, kg/hr-kW where,
BSFC Brake specific fvel consumption, kg/hr-kw
7m-Mecbanical cfficiency.

5. CHAPTER:4
DESIGN OF ENGINE PARTS
TABLE 4.1
RISTON DESIGN
Sr. No DESCRIPTION
Piston Materials
DETAILS | RELTiON
1.
Iype Allowable stress,Sd,MPa
Cast Iron 35-40
Alloy steel
Aluminium
160-100
50-90
Crown thickness, te, in mm Pmax 1/2
a) Max Pressure criteia: where;
D Diameter of piston, mm,
Pmax Maximum Gas pressure, MPa
Sa Allowablestress, MP
b) Thermal stress criteria 9D x 10
16
C14T
wiere,
te crown thickncss, cm
Ci Heal conduction factor KJ/cm-hr-°C
-
0.56, for CI,steel
- 1.986,for Aluminium.
AT Temperature difference between the
centre and edge of pison head
220° Cfor CI &steelS
75°Cfor Aluminimum
9-HHcar urilowingthrough crown,KJ/hr-c
= KxBSFCxCyxPg/A.Dc_
K fraction of heat evolved reaching to crown surface
=0.05-0.1
Pa- Brake pqwer,KW(ReferT:3.4,3.9)
BSFC BrakeSpecificfucl consumption Kg/hr-KW
Cv-Calorific valueoffuel, KJkg
-40500-.32000 kJ/kg, Petrolfuel
- 42000 4000 kJkg, Diesel fuel
A AreaofPiston,cm
neno.ofcylinders
le 0.032 D+1.5, mm.
hX iSFC
c)Empitical Relatioa:

6. TABLE:4.2
DESIGN OF PISTON RINGS
ST.NO. DESCRIPTION RELATIONS
Radial thickness of piston ring, tr ,mm
D
. t
a) BearingPressure criteria
where,
Pw Radial wallpressure,
-0.0245-0.042,N/mm
Sa-PermissibleStres,
-
84-112,N/mm,forCI
tr(0.04-0.045) D,for compression ring
-
(0.038-0.043) D, for oil control ring.
b) Empirical Relation
n 0.4/D
where,
2. Numbers of Piston rings, n
D Bore diameter, mm
n 34, for automoticengines
5-7, for stationary compression
ignition engines.
3. Axial thickncss ofPistonring,tam, mm a) Minimum axial thickness,tam
tam D/10.0
b) Empirical relation
l-(0.6to1.0)t
4 Stress in piston ring section when 1.6x Exlr
Sc
D-t+
slipped over piston, Sc, MPa where,
Kr- Ring gap when ring is being slipped
on thepiston,mm
E - Modulus of.Elasticity (Refer T: 1.2)
Sc 180MPa. x Io
5. Gap between the free ring ends, G1, mm G1 (3.5-4)!r
Gap between the ring ends when
the ringis in the cylinder, G2, mm
6. G2 (0.002-0.004)D
7. Thickness between ring grooves i.c. land, tv,mm (0.75-1.0) ta

7. TABLE:
4.7
STUD/BOLT
DESIGN
Sr.
No
DESCRIPTTON
RELATIONS
Fme+Fre
for
a&
Steel
eylinder
xFm
+Fp
Pih,
for
Aluminium
cylindei.
Fma
g/ns
n
No.
of
studs.
o.615t+4
FTotal
gas
force,N
Pma
A
Pman
Mn
gan
preasure,
N/mm
A-
Arcn
of
top
aurfaro
of
cylinder,mm
AJAp
1.7-
2.2,
for
iottom
valved.
.
1
1.3,
for
verhoad
valves.
Total
load
on
stud
F
,N
Maximum
Gas
force,
Fma,N
Preonding
forco
of
siudbol
Fpl.N
Ap
Aren
nf
piston,N/mm
F-Prcloading
(orue
of
aludboltN
LPLm(1-x)-
Pmas
m-Studbolt
tightening
coeflicient.
without
Gasket,
with
Gasket.
1.5
to
2.0.
S,
x
coeff.of
main
load
of
threaded
joint
0.15-0.25
Fih
(
a
A
Ta
lh-da
4TaL(k»+)
Thermal
load,
Fih
N
where
a
and
a
cooffs.
of
linear
espansion
of
head
and
stud
material
(ReferT:12)
A
Th&AT=increase
in
bead
&
stud
temp.
ATh-4Ts-
(70-80)
°C,forwatercooled
enginca
-
cylinder
head
height,mm
L-
length
of
stud
in
cyinder
bdad
and
gasket,t
-
la+
thickness
of
gasket,mm
Ka
and
Ka
-
coefficients
of
therml
load
in
stud
&
head,mm/N
Ka
la/EpAa.
K
BAAa
wbere,
E
&Be
Moduls
of
easticiy
of
head
and
studmaterial,
MPa
(Refer
T:12)
Ag
core
cross-sertional
area
of
stud,mm
A-Cross
-scctional
area
of
cylinder
head
per
stud,
mm.
Design
tress
in
etud
material,
SaMPa
Sa-
design
atressin
studbot
material,
MPa
(ReferT:4.8A)
Ac
Core
cross-scctional
arca
of
stud/bolt,mm
de
Core
dia
of
bolt/stud
(Refer
T:4.9)