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“The Right to Information, The Right to Live” “Step Out From the Old to the New”

IS 810 (1991): Internal Combustion Engines - Engine Valves

[TED 2: Automotive Primemovers]

“!ान $ एक न' भारत का +नम-ण”

Satyanarayan Gangaram Pitroda
“Invent a New India Using Knowledge”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता ह”

है”
ह
Bhartṛhari—Nītiśatakam
“Knowledge is such a treasure which cannot be stolen”
 IS 810 : 1991
( Reaffirmed 2006 )

Indian Standard
INTERNALCOMBUSTIONENGINES-
ENGINEVALVES-SPECIFICATION
( Second Revision )

UDC 621.646.2 : 621.43 : 629-7

BUREAU OF INDIAN STANDARDS

MANAK BHAVAN. ? BAHADUR SHAH ZAFAR MARG
NEW DELHI 110002

October 1991
Automotive Primemovers Sectional Committee, TED 2

FOREWORD

This Indian Standard was adopted by the Bureau of Indian Standards, after the draft finalized by the
Automotive Primemovers Sectional Committee had been approved by the Transport Engineering
Division Council.

This Indian Standard was first published in 1974. In this revision, the scope has been enlarged to cover
all types of engine valves ( other than aircraft engines ) presently being used by the manufacturers and
the users in internal combustion engines. The types of valves included are:

Bimetallic valves, hard faced and surface treated valves.

In the preparation of this revision ~assistance has been derived from JIS E 101 ‘Engine valves for
automobiles’ issued by the Japanese Industrial Standards Committee. ’

For the purpose of deciding whether a particular requirement of this standard is complied with, the
final value observed or calculated expressing the results of a test. shall be rounded off in accordance
with IS 2 : 1960 ‘Rules for rounding off numerical values ( revised)‘. The number of significant places
retained in the rounded off value should be the same as that of the specified value in this standard.
 h&m Standard
INTERNAL COMBUSTION ENGINES -
ENGINE VALVES - SPECIFICATION
/ Second Revision)
1 SCOPE IS No. Title
1.1 This standard specifies the general require- 3703 : 1981 Code of practice for magnetic
ments for inlet and exhaust valves for all particle flaw detection (Jirst
internal combustion engines other than for air- revision )
craft use. 7494 : 1981 Steel for valves for internal com-
1.2 Sodium filled valves, phosphated valves, bustion engines (first revision )
shrouded valves and valves with more than 12969 : 1990 Method of test for quality charac-
100 mm head diameter are not covered by this teristics of valves
standard.
3 TERMINOLOGY
1.3 The methods of test for quality characteris-
tics of engine valves are covered in IS lL969 : For the purpose of this standard the following
1990. definitions shall apply to denote the parts of a
2 REFERENCES valve ( see Fig. 1 ). The term, valve face, is to be
preferred to designate the cone shaped seating
The following Indian Standards are necessary surface of the valve and the term ‘valve seat’ is
adjuncts to this standard. to be preferred to designate the corresponding
IS No. Title mating part when the valve is assembled in the
engine.
1586 : 1968 Methods for Rockwell hardness
test ( B and C scales ) for steel 3.1 crown
( jirst revision ) The extreme upper surface of the valve head.
1608 : 1972 Method for tensile testing of steel
products (first revision ) 3.2 Valve Face
3073 : 1967 Assessment of surface roughness Coned surface of the valve that sits on the
3658 : 1981 Code of practice for liquid pene- corresponding seat surface of the cylinder head
trant flaw detection (Jirst revision ) or cylinder block, as the case may be.

CROWN VALVE FACE COTTER OR COLLET GROOVE

REFERENCE DIA TAPPET FACE

r 7
STEM DIA
r- I
HEAD
DIA

GAUGE
DIA

GROOVE WID’IH

13
LAND OR MARGIN
4
HEAD 4 STEM
4 I ?

/J~DERCUT STEM ENa

FIG. 1 TERMINOLOGY

1
IS81O:l~l .

3.3 Head 4.2 Classification of Engine Valves

That part of the valve from the crown through 42.1 The engine valves are classified as shown
the valve face. below according to type of construction, surface
treatment of-tappet seat end and stem.
3.4 Throat or Neck
Type of Tappet Seat Surface
That part of the valve connecting the valve Construction End Treatment
head to valve stem.
Single piece Untreated Untreated Untreated
3.5 Stem hardened hard faced hard
The cylindrical part of the valve including the button induction chrome-
valve guide sliding portion. welded hardened plated
and stem
3.6 Stem Underout hardened soft
hard faced nitrided
In addition to the thread or neck, a reduced
portion as shown in the Fig. 1 may be used to Two piece Untreated Untreated Untreated
connect the valve head to the stem. This reduc- ( bi- hardened hard faced hard
tion in size is with reference to the stem metallic ) chrome-
diameter. plated
stem
3.7 Cotter ( Collet ) Groove or Grooves
That part of the valve meant forthe insertion of 5 MATERIAL
cotter ( collet ). 5.1 Uniess otherwise specified steels for valves
shall conform to IS 7494 : 1981.
3.8 Stem End
That portion of the valve stem between the 5.1.1 Recommended materials for valves, hard-
groove and tappet face. facing alloys for valves and heat treatment
particulars are given in A-l, A-2 and A-3 respec:
3.9 Reduced Stem End tively.
That portion of the stem near the tappet face 5.2 Tensile Strength
which is reduced below the stem diameter.
The valves shall have a minimum tensile
3.10 Tappet Face strength of 80 kgf/mma when made from a
martensitic steel and 70 kgf/mma when made
The extreme end of the stem that comes in from an austenitic alloy, when tested as
connect with the tappet, the rocker arm or the per IS 1608 : 1972. A bimetallic valve shall
valve cap as the case may be. have minimum tensile strength of 70 kgf/mms
3.11 Land or Margin ( see IS 12969 : 1990 ).

That part of the valve between the crown and 5.3 Heat Treatment
the valve face. Valves made from martensitic steels or austeni-
tic alloys shall be used either in the fully heat
3.12 Gauge Diameter treatment condition or in the forged and stress-
An imaginary geometrical contact diameter relieved condition subject to the minimum
between the valve face and seat. tensile strength specified in 5.2. The heat treat-
ment particulars for the alloys are given in A-3.
3.13 Reference Diameter Valves made out of martensitic steels when
hardened and tempered shall have a general
A nominal value, designated to enable measure- hardness of 25 to 35 HRC, when tested as
ment of head thickness against a fixed reference. per IS 1586 : 1968.
4 TYPES OF VALVES 5.3.1 Any other range of hardness may be
agreed upon between the purchaser and the
4.1 The two main types of valves are: supplier.
a) Single piece valve; and 6 MANUFACTURE OF VALVE FORGINGS
b) Two-piece or bimetallic construction. 6.1 The valve forgings shall be manufactured
either by the upsetting process or by extrusion.
‘There can be additional features by way of
surface treatment and hard facing as well as 6.2 The grain flow shall be continuous and
local hardening. shall generally follow the throat contour.

2
 Is 810 : 1991

7 DIMENSIONS AND TOLERANCES 9 TAPPET FACE HARDNESS

7.1 Stem Diameter 9.1 For such of those valves that are locally
The following preferred nominal stem diameters hardened at the tappet end the minimum tappet
in mm for valves are recommended: face -hardness shall be 48 HRC. However, for
the steel X80Cr20Si2Ni1, the minimum hardness
5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0. 8.5, 9.0, 9.5, 10, applicable shall be 46 HRC. The depth of hard-
11, 12, 13, 14. ness shall generally be between 1 to 3 mm and
NOTE - Valves with higher stem diameters can be in the hardened zone shall not extend into the
steps of 1 mm or more to meet any specific require- cotter/collet groove. The depth of hardness
ments. shall be assessed as the total case depth shown
7.2 Valves dimensions shall be as indicated in by macroetching.
Fig. 2. The tolerances on these indicated dimen-
sions shall be in accordance with Table 1. 9.1.1 However, other specific minimum hardness
Table 2 indicates the permissible tolerance for values, other depth patterns, such as hardening
stem -diameter dimensions. through and beyond the groove region, specifi-
cations of effective case depth in place of total
7.3 Surface Finish case depth shall be mutually agreed to between
7.3.1 The surface finish shall be measured as per the purchaser and the supplier.
IS 3073 : 1967 and the maximum value shall be
as per Table 3.
IO HARDENED VALVE FACE
7.4 Geometrical Tolerances
Valve shall be induction or flame hardened at
7.4.1 The geometrical tolerances on measure- the valve face as shown in -Fig. 6 when so
ments of characteristics shall be as given desired to increase the wear resistance. The
in Table 4. depth of hardening shall cover completely the
7.5 For purposes of guidance, tolerance for valve face and shall not extend more than 2 mm
certain other areas of the valve are indicated on the valve neck region adjoining the valve
in Fig. 4 ( see Fig. 3 ). face. The recommended minimum hardness for
8 LOCKING ARRANGEMENT induction hardened valve face is 45 HRC.
Induction hardening of valve is applicable only
Figure 5 gives the general valve locking arrange- to the martensitic grades of steels listed
ments ( cotter/collet groove shapes ). in A-l.

to.10 +0*05
-0.15 -0.15

r
6 d,

All dimensions in millimetres.

FIG. 2 DIMENSIONS - MAJOR

3
IS 810 : 1991

Table 1 Dimensional Tderanees for Vahes Table 3 Surface Fin&h (M Crowd Regioas
( Clause 7.2 and Fig. 3 ) ( Clause 7.3.1 )

Dimension Symbol Tolerance Surface Finish p Ra, Max

mm
Stem 0‘5
(1) (2) (3) Valve face 0’8
Head diameter Dt f 0’10
Tappet face 0’6
Gauge diameter DP f 0’00
Reference diameter 03 f 0 00 11 HARDFACING OF VALVE FACE
Stem diameter dt Refer Table 2
The hardfacing and induction hardening of
Underout diameter da c I- 0 10
valve face shall be as shown in Fig. 6. The
t - 0’15
corrosion and wear resistance of the valve face
Cotter ( collet 1 groove ds shall be increased and the service life of valves
diameter { _+ “0.7:
in general and exhaust valves in pariicular shall
Head thickness Tl + 0’25 be extended when a suitably machined groove at
Face height T2 f 0’20 the valve face is hardfaced with an alloy that is
Reference thickxess T3 f 0’25 superior to the valve material as shown in Fig. 6.
Overall length L * 0’25 The deposit shall be made by oxyacetylene or
Length from crown to La f 0’20 by any other approved method of welding
groove position (see A-2).
Co;;r&yollet ) groove L8 f + 0‘15 12 SURFACE TREATMENT FOR VALVES
<1 - 0’05

Valve face angle f + 30’ 12.1 The valve shall be given one of the follow-
< - 0’ ing two surface treatments, to improve the anti-
1
1)Not applicable in the case of round and tapered seizure properties of the valve stem in particular
grooves. and the corrosion resistance of the valve in
general. The testing procedures are outlined
in IS 12969 : 1990.
Table 2 Dimensions for Stem Diameters
( Clause 7.2 ) 12.1.1 Hard Chromium Plating
Figure 7 shows the details of the stem region
Stem Diameter Tolerances protected by hard chromium platjng along with
mm mm
the suggested minimum plating thickness. When
3-6 - 0’01.5
specified, the hard chromium plating shall be
> 6-10 - 0’020 carried out in a~plating bath by any one of the
>lO-18 - 0’025 standard electrochemical methods. The plating
NOTE - Tolerance for stem diameter 18 mm and thickness shall be 0.003 mm minimum. Higher
above shall be as agreed to between the purchaser plating thickness values shall be as agreed to
and the supplier. between the purchaser and the supplier.

FIG. 3 GBOMBTRYAND SURFACB ROUGHNESS

4
 IS 810 : 1991

Table 4 Geometrical Tolerances, mm 12.1.2 Soft Nitriding

( Clause 7.4.1 ) When specified the soft nitriding shall be carried
out either by gas nitriding or liquid nitriding, to
Face runout 0’03 for head diameter a minimum total case depth of O+OlOmm and a
up to 50 mm minimum hardness of 500 HV at 200 g load.
0’04 for head diameter of
50 mm and above but 13 BUTTON WELDED NORHARDFACED
below 75 mm11 TAPPET FACE
Stem circularity 0’01
13.1 Austenitic valves in general and martensi-
Stem straightness 0’01 tic valves in a few cases shall be constructed in
Stem cylindricity Half the stem diameter one of the following two wavs to provide
tolerance subject to a increased hardness and wear resistance at the
minimum of 0’010
tappet end.
-Groove runout 0‘10
Tappet face runout 0’03 13.1.1 The valve shall have a welded button of
Crown face runout 0’20 a hardenable wear resistant ( martensitic ) steel
which shall have a thickness in the range of
l)The face runout for valves with head diameter 2 to 3 mm. .This region shall subsequently be
75 mm and above shall be mutually agreed to between
the purchaser and the supplier.
hardened to a minimum tappet face hardness
of 48 HRC.
f0.20

DETAIL X

AI1 dimensions in millimetres.

FIG. 4 DIMENSIONS : OTHER AREAS: MINOR

Al1 dimensions in millimetres.

FIG. 5 LOCKING ARRANGEMENT ( COLLET/COTTER GROOVE )

5
 a) b) e) d)
All dimensions in millimetres.
FIG. 6 HARDFACINGANDINDUCTIONHARDBNINGOF VALVE FACE

CF FAOEO AREA 3 CHROMIUM PLATEO OR _ 1: NON CF

FLASHED AREA (CF) REGION

7 Bd,

_ _
?
!
. -

- 0.006
- o*ooo
CF 3 CHROMIUM PLAl:EO OR FLASH 04 !

FIG. 7 CHROMIUMPLATING

13.1.2 Hardfacing of the tappet face shall con- an external gap width and depth of 0.2 mm
sist of depositing by oxy-acetylene flame or by maximum are permitted. Longitudinal seams
any other approved welding methods, approxi- typical of continuously cast raw material is
mately 1 to 2 mm layer of a wear resistant permitted over the stem region of the valve but
material. A few typical hardfacing alloys, along shall not extend into the undercut or groove
with values of minimum hardness obtainable regions. The depth of these seams shall be less
after hardfacing, are indicated in A-2. Other than 0.5 mm and the root shall not be a
alloys, not indicated in A-2 shall be used subject V-notch.
to agreement between the purchaser and .the
15 TESTS
supplier.
15.1 Macro Etch Examination
14 SURFACE IMPERFECTIONS
151.1 Valves shall be subjected to a grain flow
14.1 The valve shall be free of tool marks or detection test by hot etching in hydrochloric
any other cut marks that are likely to interfere acid, cold etching in Marble’s Reagent, or by
with the functioning of the valve. However, any other approved method of macro etching.
certain minor blemishes due to forging, machin- The etching shall be done so as not to cause
ing or handling shall be permitted subject to excessive pittings and corrosion of the sample.
agreement between the purchaser and the sup- The grain flow shall be continuous and shall
plier. Typical minor forging flaws are those in generally follow the throat contour.
the crown and throat ( neck ) regions and shall
not be deeper than 0.5 mm and the root shall 15.2 Crack Detection Test
not be a V-notch. Hardness check marks taken 15.2.1 Valves when tested for crack detection
onRockwell ‘A’ scale or Vickers are acceptable. by the magnetic crack detection, the colour,
Circumferential indications either in visual dye penetrant, the fluoroscopic dye penetrant
inspection or in crack detection are not accept- or by any other approved method as agreed to‘
able except at the button welded interface where between the purchaser and the supplier, shall,

6
 IS 810 : 19Yl

be found free from cracks ( see 1s 3 703 : 1980 16 MARKING

and IS 3658 : 1981 ).
16.1 Each valve shall be legibly and indelibly
marked, part number, batch number and source
15.3 Microstructure Test of manufacture. The markings shall be such
that they do not interfere with the function of
15.3.1 Valves shall be subjected to a microstruc- the valve.
ture test by an approved method of specimen
preparation and the structure so observed shall 16.2 Valves shall not be deeply stamped on the
correspond to the type of steel or alloy used crown for identification and the method of
and the heat-treatment carried out on the valve. marking shall be as agreed upon between the
The three types of heat treatment conditions purchaser and the supplier.
for valve material are: 17 PRESERVATIVE TREATMENT
a) Hardened and tempered structure for the Each valve shall be coated with a suitable rust
martensitic steels, preventive oil or medium which is easy to
remove when required for subsequent assembly.
b) As-rolled and annealed structure, or 18 PACKING
c) Solution treated structure for the austeni- Valves shall be packed suitably as per the best
tic alloys. prevalent trade practice.
 ANNEX A
( %lauses5.1.1 and 10.1 )
RECOMMENDATIONS FOR VAi,VES HARDFACING AND TEMPERATURE FOR HEAT TREATMENT

A-l MATERIALS FOR INLET AND EXHAUST VALVES

Sl Material Type C Si Ni Cr MO W V Na S P
No. Max Max
1. 4OCr4 M 0’35-0’45 0’10-0’35 0’60-0’90 - 0’90-1’20 - - - - 0’04 0’04
2. 40NiOCr4Mo3 M 0’35-0’45 0’10-0’35 0’40-0’70 1.25-l ‘75 0’9-1’3 0’2-0’35 - - - 0’035 0’04
3. X50Cr9Si2 M 0’45-0’55 1 ‘O-2.0 0’6 Max 0’6 Max 7’5-9’5 - - - - 0’035 0’04
4. X45Cr9Si3 M 0’40-0’50 2’75-3’75 0’80 Max 0’50 Max 7’50-9’50 - - - - 0’035 0’04
5. X40CrllSiZMol M 0’35-0’45 1’8-2’5 0’6 Max 10‘0-12’0 0’7-1’3 - - - 0’035 0’04
6. X80Cr20Si2Nil M 0’75-0’85 1’75-2’50 0’80 Max 1’00-1’70 19’0-21’0 - - - - 0’035 0’04
7. X45019Ni9Si3Wl A 0’4-0’5 2’0-3’0 0.8-l ‘5 8’0-10’0 17’0-20’0 - 0’8-1’2 - - 0’035 0’05
8. X20Cr21Ni12N A 0’15-0’25 0.75-l ‘25 1’5 Max l”.5-12.5 20’0-22’0 - - - 0’15-0’30 0‘035 0’05
9. X70Cr21Mn6Ni2N A 0’65-0’75 0’45-0’85 5’5-7’0 1‘4-1’9 20’0-22’0 - - - 0’180’28 6’035 0’05
10. X55Cr21Mn8Ni2N A 0’50-0’60 1’0 Max 7’0-9’5 1’5-2’75 20’0-22’0 - - - 0’20-0’40 0’035 0’05
11. X53Cr22Mn9Ni4N A 0’480’58 0’25 Max 8’0-10’0 3’25-4’50 20’0-23’0 - - - 0’38-0’50 0’035 0’05
12. X30Cr20NillMo2P A 0’25-0’35 1’0 Max 1’2 Max 10’0-12’0 19’0-21’0 1’8-2’5 - B. O’Ol- - 0’035 0’18-0’25
13. X33Cr23Ni8Mn3N A 0’28-0’38 0.5-l ‘0 1’5-3’5 7’0-9’0 22’0-24’0 - - - 0’25-0’40 0’035 0’05
14. Nickel Alloy SOA A 0’10 Max 1’0 Max 1’0 Max Base 18’0-21’0 Ti 1 ‘O-2.70 Al 1 ‘O-1‘80 d’03 0’045
Fe 3’0 Max Co 2’0 Max
15. Nickel Alloy 751 A 0’10 Max 1-o Mnx 1’0 Max 70’0 Min 14’0-17.0 Ti 2’0-2’6 Fe 5’0-9’0 0’03 0’045
Al 0’9-1’5 Nb+Fa 0’7/1’2

NOTES
1 Alloys 9, 10 and 11 may have sulphur upto 0’09 percent for free machining.
2 The letter ‘M’ has been used to denote Martensitic steels and the letter ‘A’ to denote Austenitic steels/alloys.
 IS 810 : 1991

A-2 MATERIALS FOR VALVE ,HARDFACING

(Clauses 11 and 13.1.2 )

Alloy C Si lpin Ni Cr Co W Fe Deposit Typica?

H;arcess Application

CoCr Alloy 2’0-3’0 0’4-2’0 1.0 Max 3’0 Max 26’0-33’0 Base 11’0-14’0 3’0 Max 48 Min Tappet end
Type 1
CoCr Alloy 1 ‘O-l ‘7 0’4-2’0 1’0 Max 3’0 Max 26’0-33.0 Base 7’0-9’5 3’0 Max 45 Min Tappet end
Type 12 and valve
face
CoCr Alloy 0’9-1’4 0’4-2’0 1’0 M’ax 3’0 Max 26’0-33’0 Base 3’0-6’0 3’0 Max 38 Min Valve face
Type 6
CoNiCr Alloy 1’5-2’0 0’9-1’3 0’3 Max 21’0-23’0 24’0-27’0 Base 11’5-13’0 0’85-1’35 38 Min valve face
Type 32
Nickel Alloy 0’3-0’7 2’5-5’0 3’0 Max 58’0-63’0 14’0-18’0 - - Balance 20 Min Valve face
60
FeCrNiMo 2’0-2’5 0’8-1’3 - 10’0-12’0 22’0-26’0 - MO Base 35 Min Valve face
Alloy 5’0-6’0
Fe Cr Alloy 2’5-2’7 - - - 25’5-28’5 - - Base 50 Min Tappet face

NOTE - The hardness figures given refer to the as cast hardness and the hardfacing alloys are not heat-treatable.

A-3 HEAT TREATMENT TEMPERATURES FOR VALVE MATERIALS

( Clause 5.3 )

Sl material Temperature, SC!

No. r---_---_---------- A------------,__-_
Harden TemperlSR Solution AGE/SR* ’
Treat
1. 40Cr4 860-890 550-700 - -
2. 40Ni6Cr4Mo3 820-850 500-660 - -
3. X50Cr9Si2 1 000-l 050 650-750 - -
4. X45Cr9Si3 1 020-l 070 720-820 - -
5. X40Crll Si2Mol 980-l 080 700-800 , - -_
6. X80Cr20Si2Nil 1 050-I 080 700-800 - -
7. X45Crl9Ni9Si3Wl - - 980-I 080 -
8. X20Cr21Ni12N - - 1 100-l 200 700-800’
9. X70Cr21 Mn6Ni2N - - 1 100-l 200 730-780
10. X55Cr21Mn8Ni2N - - 1 100-l 200 730-780
11. X53Cr22Mn9Ni4N - - 1 100-I 200 730-800
12. X30Cr20Nill Mo2P - - 1 120-l I50 730-760
13. X33Cr23Ni8Mn3N - - 1 100-l 180 760-790
14. Nickel Alloy 80 A - - 1 020-l 100 700-750
15. Nickel Alloy 751 - - 1 020-l 100 700-800
~___
*NOTE - Ageing is optional.

9
Standard Mark
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Standards Act, 2986 and the Rules and Regulations made thereunder. The Standard Mark on
products covered by an Indian Standard conveys the assurance that they have been
produced to comply with the requirements of that standard under a well defined system of
inspection, testing and quality control which is devised and supervised by BIS and operated
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formity to that standard as a further safeguard. Details of conditions under which a licence
for the use of the Standard Mark may be granted to manufactures or producers may be
obtained from the Bureau ~of Indian Standards.
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harmonious development of the activities of standardization, marking and quality certification of goods
and attending to connected matters in the country.

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Revision of Indian Standards

Indian Standards are reviewed periodically and revised, when necessary and amendments, if any, are
issued from time to time. Users of Indian Standards should ascertain that they are in possession of the
latest amendments or edition. Comments on this Indian Standard may be sent to BIS giving the
following reference:

Dot : No. TED 2 ( 5155 )

Amendments Issued Since Publication

Amend No. Date of Issue Text Affected

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