ASTM D2562-94

Designation: D 2562 – 94
Standard Practice for
Classifying Visual Defects in Parts Molded from Reinforced
1
Thermosetting Plastics
This standard is issued under the fixed designation D 2562; 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 nicks, cracks, shorts, etc. Molded-in threads may be retapped
or repaired unless otherwise specifically noted on the product
1.1 This practice covers acceptance criteria for visual in-
drawing.
spection of parts molded from reinforced thermosetting plastics
2.5 Workmanship—Workmanship shall be in accordance
by compression and transfer molding.
with good commercial practices.
1.2 One objective of this practice is to present word descrip-
2.6 Critical Areas—Areas in which the presence of imper-
tions of possible defects to serve as a guide for contracts,
fections is considered to be detrimental to the proper function
drawings, product specifications, and final inspection.
of the part shall be designated as critical areas. The areas of a
1.3 This practice also categorizes different inspection re-
part that are critical structurally, aerodynamically, or electri-
quirements for grades of product quality.
cally shall be uniform and free of defects as listed in Table 1,
1.4 The values stated in SI units are to be regarded as the
if so stated on the product drawing. Critical areas may be
standard. The values given in parentheses are for information
designated on the product drawing by one of the following
only.
means,
1.5 This standard does not purport to address all of the
2.6.1 Encircle critical areas, or
safety concerns, if any, associated with its use. It is the
2.6.2 Cross-hatch areas to designate areas of various levels,
responsibility of the user of this standard to establish appro-
or
priate safety and health practices and determine the applica-
2.6.3 Word description.
bility of regulatory limitations prior to use.
2.7 Acceptable Defects—Unless otherwise specified, the
NOTE 1—There is no known ISO equivalent to this practice.
following defects shall be acceptable in all instances:
2.7.1 Ripple Surface—Generally occurs in parts molded
2. Acceptance Criteria
from long, glass-fiber-filled, high-impact-type plastics. Such a
2.1 The method and frequency of sampling and the allow-
surface is a phenomenon resulting from the difference in
able defects may be previously agreed to by the purchaser and
shrinkage between the resin binder and reinforcement.
the seller.
2.7.2 Shrink-Mark—A dimple-like depression in the surface
2.2 Dimensions and Tolerances—Molded parts shall be
of a molding where it has retracted from the mold, and which
inspected for conformance with the dimensions and tolerances
has well-rounded edges. A shrink-mark generally occurs on
specified on the product drawing. Parts with any dimensions
one surface of a part where there is a boss, flange, rib, or other
falling outside the specified limits shall be rejected.
heavy section on the opposite surface. The shrink-mark may be
2.3 Inserts—All inserts, nuts, studs, and lugs shall not be
caused by the difference in total shrinkage when there is a
damaged in any way, nor coated with molding materials in
sudden change in section along the surface of the part.
such a way as to impair function or mechanical fit. Threads in
2.7.3 Resin Voids—Applicable to chopped fabric-reinforced
molded-in inserts shall be clean, smooth, and free of nicks,
molding compounds only, appearing as multiple surface inter-
tears, or other damage. There shall be no molding material or
ruptions which conform to the pattern of the cloth weave. This
flash on the threads. If necessary, threaded inserts may be
is usually due to an insufficient flow or shrinkage of the resin,
retapped to clean them or remove flash. Threads containing
which fails to fill all of the interstices of the fabric reinforce-
locking features may not be retapped.
ment. These defects occur only at the surface layer of resin in
2.4 Molded-In Threads or Cored Holes— Molded-in
contact with the mold.
threads or cored holes shall be free of visible defects, such as
2.7.4 Surface Discoloration—An apparent nonuniformity
of a material, evidenced by the appearance of dark streaks.
1
This practice is under the jurisdiction of ASTM Committee D-20 on Plastics Surface streaks are frequently caused by incorporation into the
and is the direct responsibility of Subcommittee D20.18 on Reinforced Thermoset-
plastic of ejector pin lubricant, mold release, or metallic matter
ting Plastics.
abraded from ejector pins.
Current edition approved Feb. 15, 1994. Published April 1994. Originally
2.7.5 Weld- or Knit-Lines—Marks on, or weaknesses in, a
published as D 2562 – 66 T. Last previous edition D 2562 – 70(1988).
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