INTERN MPAPS A-37 PDF

This specification covers requirements for stainless and heat resistant fasteners and the raw material requirements for stainless and heat resistant steel sheet, strip, plate, tubing, pipe, and wire material used in the Company’s parts, assemblies and fasteners. Additional requirements may apply as noted below.

NOTES:

• Refer to MPAPS A-9 for stainless steel spring wire.

• Refer to MPAPS F-1050 for stainless steel flexible pipe/hose used in exhaust systems.

• Refer to MPAPS F-1058 for stainless steel tubing used in engine air/fluid systems.

• Refer to MPAPS F-1068 for stainless steel bellows used in exhaust system.

• Refer to MPAPS F-1069 for stainless steel tubing used in exhaust systems.

• Refer to MPAPS P-9563 for stainless steel used in diesel exhaust fluid tanks.

This specification also defines the mechanical and chemical finish requirements for stainless steel surfaces, including requirements for passivation, electropolished, electropolished with chrome flash, or electrolytically micro-etched, for parts requiring a decorative, color match, corrosion/heat resistant finish, or “paint-ready” stainless steel surface. Such parts might include bright reflective grab handles, sunshades (requiring color match), exhaust pipes which require both corrosion and heat resistance, or passivated stainless steel fasteners.*

*NOTE: Stainless steel fasteners (i.e., bolts, nuts, washers, etc.) that are passivated in accordance with this specification are not required to undergo CASS testing, unless specified.

This specification does not cover cast or powdered stainless steel.

APPLICATION

This specification applies to stainless steel fasteners, exhaust pipes, tubing, heat shields, and other parts used in high temperature applications and/or where corrosion resistance is needed. Stainless steels offer good mechanical strength over a wide range of temperatures and provide corrosion resistance superior to all of the common structural steels. Some alloys can be buffed and polished for improved surface appearance. Passivation of stainless steels can be performed to ensure a clean surface, free from ironbearing contaminants which may result in undesirable rust and degraded surface appearance. However, on bright or polished parts, passivation may somewhat reduce the glossy or polished appearance.