ASTM A748/A748M-87(1998)

Standard Specification for Statically Cast Chilled White Iron-Gray Iron Dual Metal Rolls for Pressure Vessel Use

SCOPE
1.1 This specification covers statically cast dual metal rolls with the outer layer of the roll body being chilled white iron of different chemical composition than the core and journals of the roll which is gray cast iron. The castings are suitable for pressure containing parts, the design strength of which is based on the gray iron portion of the cylinder. The castings are suitable for service at temperatures up to 450°F [232°C].
1.2 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independent of the other. Combining values from the two systems may result in nonconformance with the specification.

General Information

• Status: Historical
• Publication Date: 09-Oct-1998
• Technical Committee: A04 - Iron Castings
• Drafting Committee: A04.01 - Grey and White Iron Castings

Relations

• Replaced By: ASTM A748/A748M-87(2003) - Standard Specification for Statically Cast Chilled White Iron-Gray Iron Dual Metal Rolls for Pressure Vessel Use
• Effective Date: 10-May-2003

Standards Content (Sample)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: A 748/A748M – 87 (Reapproved 1998)
Standard Specification for
Statically Cast Chilled White Iron-Gray Iron Dual Metal Rolls
for Pressure Vessel Use
This standard is issued under the fixed designation A 748/A748M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.1 ASTM designation and year of issue,
3.1.2 Dimensions of dual rolls,
1.1 This specification covers statically cast dual metal rolls
3.1.3 Class of gray iron in the roll core (see 4.2),
with the outer layer of the roll body being chilled white iron of
3.1.4 Inspection requirements, if different (see 10.1),
different chemical composition than the core and journals of
3.1.5 Certification, if required (see 11.1), and
the roll which is gray cast iron. The castings are suitable for
3.1.6 Special position of marking information, if required
pressure containing parts, the design strength of which is based
(see 12.1).
on the gray iron portion of the cylinder. The castings are
3.2 Any additional requirements not covered in this speci-
suitable for service at temperatures up to 450°F [232°C].
fication are subject to agreement between the manufacturer and
1.2 The values stated in either inch-pound units or SI units
purchaser.
are to be regarded separately as standard. Within the text, the
SI units are shown in brackets. The values stated in each
4. Materials and Manufacture
system are not exact equivalents; therefore, each system must
4.1 The melting procedure shall be optional with the
be used independent of the other. Combining values from the
foundry.
two systems may result in nonconformance with the specifi-
4.2 The chilled white iron exterior of the roll body shall be
cation.
made to a minimum hardness of 60 Scleroscope “C”. The gray
1.3 The following safety hazards statement pertains only to
iron portion of the roll shall conform to the applicable class of
the test method portion, Section 9, of this specification: This
Specifications A 278 and A 278M, as determined by design
standard does not purport to address all of the safety problems,
requirements. The scope of this specification shall include Nos.
if any, associated with its use. It is the responsibility of the user
20, 25, 30, and 35 of Specification A 278 [Nos. 150, 175, 200,
of this standard to establish appropriate safety and health
and 250 of Specification A 278M].
practices and determine the applicability of regulatory limita-
4.3 The casting process shall be controlled to produce a
tions prior to use.
metallurgical bond between the chilled white iron exterior and
2. Referenced Documents gray iron interior of the roll body.
2.1 ASTM Standards:
5. Test Requirements
A 278 Specification for Gray Iron Castings for Pressure-
2 5.1 Tensile Requirements—Tensile bars removed from a
Containing Parts for Temperatures Up to 650°F
prolongation at one end of the roll journal, in accordance with
A 278M Specification for Gray Iron Castings for Pressure-
2 Specifications A 278 and A 278M, shall have a tensile strength
Containing Parts for Temperatures Up to 345°C [Metric]
not less than 80 % of that specified by the applicable class of
A 667/A667M Specification for Centrifugally Cast Dual
2 Specifications A 278 and A 278M.
Metal (Gray and White Cast Iron) Cylinders
5.2 Thickness of Chilled White Iron:
3. Ordering Information 5.2.1 The thickness of the clear chilled white iron plus the
mottled iron at the roll face shall not be more than 30 % of the
3.1 Orders for material under this specification shall include
total finished wall thickness.
the following information:
5.2.2 The thickness of the chilled white iron exterior of the
roll body shall be determined by measuring the chill depth at
This specification is under the jurisdiction of ASTM Committee A-4 on Iron
the ends of the roll face.
Castings and is the direct responsibility of Subcommittee A04.01 on Grey and White
Iron Castings.
Current edition approved Oct. 30, 1987. Published December 1987. Originally
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