MIL-STD-407
15 February 1957
3.6 Staking, bad. The condition where an
1. SCOPE AND PURPOSE
insert is not in the correct position.
1.1 Scope. This document covers the de-
4. DEFECT DESCRIPTIONS AND CLAS-
fects for conventional rubber molded items, that
SIFICATION
is, articles which are made by curing rubber
compounds in a forming mold. Cast plastisol
4.1 Since the classification of certain de-
items, "O" rings, pneumatic tires and tubes,
fects depends on the service requirements of
molded rubber fuel tanks, ebonite items and
the item, it is imperative that the end use be
items containing cellular rubber are specifically
k n o w n before inspection is started. In the
excluded.
majority of cases, the end uses will be apparent
1.2 Purpose. The primary objective of this
or can be readily determined from the procure-
document is to present word descriptions and
ment document. However, in case of doubt,
photographs of possible defects in rubber molded
the cognizant technical bureau or agency (on
items that may be presented for inspection. In
primes) or the endorsing inspection service (on
addition it provides a training aid for inspectors.
subs) should be requested to supply this
information.
1.2.1 In general, this document is not in-
tended to take the place of a particular inspec-
4.2 The classification of defects for molded
tion procedure aid which may be provided for
items is more complex than that for a single-
inspectors to verify conformance with a par-
shape, single-application item such as V-belts.
ticular specification. The quality requirements
Molded items are produced in a nearly infinite
specified in the basic specification are governing.
variety of sizes and shapes so that there is no
common or typical shape for this class of item.
2. REFERENCED DOCUMENTS
Also, these items have several principal end
2 . 1 Standards
u s e s or service requirements which are dis-
MILITARY
similar in the amount of perfection or quality
M L - S T D - 1 0 5 -- S a m p l i n g Procedures
r e q u i r e d . These include the following:
a n d Tables for Inspection by At-
tributes.
(a) Flexing --A primary use where the
.
MIL-STD-177--Rubber Products,
i t e m undergoes constant or inter-
Terms for Visible Defects of.
mittent bending, twisting or deflect-
(Copies of specifications, standards, drawings, and
ing during service such as a vibra-
publications required by contractors in connection with
tion isolation mounting.
specific procurement functions should be obtained from
(b) Sealing --A primary use where the
the procuring agency or as directed by the contracting
item serves as an airtight or water-
officer.)
tight closure such as a gasket or a
3. DEFINITIONS
boot.
3.1 The categories, major and minor defects,
(c) Barring (barrier material) --A primary
.
are as defined in Standard MIL-STD-105.
use where the item serves as an im-
3.2 Word descriptions of defects used in this
p e r v i o u s material to passage of a
s t a n d a r d are in accordance with Standard
liquid or gas such as a diaphragm or
MIL-STD-177.
pneumatic closure.,
3.3 Location I defect. The condition where
(d) Matching A primary application for
the imperfection occurs on a primary use part
d i m e n s i o n a l tolerances where the
of the item surface as regards dimensional toler-
item must be assembled with mating
ances or physical stress in service.
parts such as a stud mounting or a
3.4 Location II defect. T h e c o n d i t i o n
cable connector.
where the imperfection does not occur on a
(e) Protecting-An intermediate use where
primary use part of the item surface as regards
the item serves as a covering mate-
d i m e n s i o n a l tolerances or physical stress in
rial and physical stress is non-exist-
service.
ent or occurs infrequently, such as a
3.5 Fabric, floating. The condition where
brake pedal.
a reinforcing fabric is not in the correct position.
1