More info
Description / Abstract:
These engine coolant hoses or assemblies incorporating these
coolant hoses are intended to withstand the effects of circulating
solutions containing corrosion inhibitors and glycols and operating
under various pressure conditions at continuous operating
temperatures from 40 °C to maximum temperatures ranging from 120 °C
to150 °C, dependent on type.
The tube and cover stocks of these hoses shall be made from
ethylene propylene diene monomer (EPDM) compounded and reinforced
with appropriate yarn (as described in 1.1) to meet the
requirements of this specification. The radial thickness of the
lining shall be at least 50% of the total wall thickness. Cover may
be perforated to facilitate degassing during manufacturing
operations. Hose shall be black. Alternate reinforcement may be
permitted with Engineering Source Approval, and this alternate
reinforcement will be referenced as the approved reinforcement for
that specific hose approval in MATSPC. Use of high tensile modulus,
low elongation polyaramid materials (i.e., Technora, Kevlar, and
Twaron) may not be suitable for heater hose part numbers which are
formed with small bend radii and used for dynamic applications. For
additional information or aid in selection of proper reinforcement
materials for specific part numbers, contact the regional Materials
Engineer. No Rubber Manufactures Association (RMA) defined colored
tracer or other identifying thread shall be added to the
reinforcement specified for the construction of the hose.
Material Description.
Materials covered by this specification are divided into several
types, defining the material content, construction, and performance
limits of each specific type of hose. Types D, F, and G are
considered preferred types which should be used for all production
hose releases unless there is a specialized application requiring a
unique hose construction. If there is a unique hose application for
which one of the other types might be considered or required,
contact the GM Materials Engineer to discuss the appropriate hose
type that should be used.
Refer to Appendix D, Table D1 and Table D2 for requirements to
Type A, Type B, and Type C for legacy and service usage.
Type D. EPDM coolant hose, sulphur cured
utilizing aramid reinforcement, capable of operating to a maximum
continuous temperature limit of +130 °C, and formulated to contain
zero (0) weight percent thiuram, and a maximum of 0.04 weight
percent thiocarbamates in the EPDM rubber stock for both hose tube
and cover.
Type E. EPDM coolant hose, peroxide cured
utilizing aramid reinforcement, capable of operating to a maximum
continuous temperature limit of +150 °C. A Dicumyl peroxide cure
system may not be used for this hose.
Type F: EPDM coolant hose, peroxide cured
utilizing aramid reinforcement, capable of operating to a maximum
continuous temperature limit of +150 °C, but having greater
expansion under pressure than Type E. A Dicumyl peroxide cure
system may not be used for this hose.
Type G: EPDM coolant hose, peroxide cured
utilizing aramid reinforcement, capable of operating to a maximum
continuous temperature limit of +150 °C. A Dicumyl peroxide cure
system may not be used for this hose.
Type H: EPDM coolant hose, peroxide cured
utilizing Polyethylene Terephthalate (PET) reinforcement, capable
of operating to a maximum continuous temperature limit of +120 °C.
A Dicumyl peroxide cure system may not be used for this
hose.
Symbols. Not applicable.
Typical Applications. This specification covers
the material requirements of ethylene propylene diene monomer
(EPDM) engine coolant hose, both large diameter (radiator hose) and
small diameter (heater hose). In addition, this specification
covers the material requirements for engine coolant hose which is
incorporated into crimped metal pipe and hose assemblies, or which
is incorporated into molded branched hose assemblies. The
performance requirements for engine coolant hose and assemblies
incorporating engine coolant hose are defined by additional
performance specifications.