Important Manufacturing Process List

This list is intended for use when no critical characteristics have been defined by the ESA for a critical safety item.


1. Chemical Cleaning Processes:

A. Degreasing compounds used.

B. Cleaning and/or etching compound used.

C. Cleaning and/or etching compound controls (i.e., storage, contamination, temperature

used, cycle time used).

D. Method of neutralizing after chemical cleaning.

E. Cleaning sequence used.

F. Pre or post cleaning preparation.


2. Mechanical Cleaning Processes Using Energized Media (Vapor Blast, Dry Grit Blast, Tumbling and Allied Processes):

A. Cleaning media used (Type, AL2O3, Sand, Shot, etc.).

B. Size of cleaning media used.

C. Method of applying energy to media (e.g., air pressure, mechanical, etc.).

D. Liquid vehicle used (water, additives, etc.).

E. Cleaning sequence and operating parameters used.

F. Pre or post cleaning preparation.


3. Welding Processes:

A. Geometry of weld joint.

B. Preparation of weld joint including cleaning.

C. Control and type of coverage and backup atmosphere used.

D. Weld sequence and schedules used.

E. Type and control of filler material used (size, form, chemistry, cleaning).

F. Pre or post cleaning preparation.


4. Brazing Processes:

A. Surface preparation used (cleaning, etching, etc.).

B. Fit up and/or joint geometry.

C. Location of and form of alloy used.

D. Flux media used.

E. Brazing temperature and time cycle used.

F. Furnace temperature and control of atmosphere used (vacuum, etc.).

G. Brazing sequence used.

H. Flux removal process used.

I. Stop-off system used including compounds and their control.

J. Pre-braze furnace control and preparation.


5. Soldering Processes:

A. Joint preparation used (tinning, dip, etc.).

B. Fit up of joint geometry.

C. Flux media and system used.

D. Soldering method used (dip, resistance, etc.).

E. Pre and post preparation and cleaning.

F. Soldering alloy used.


6. Casting Processes:

A. Melting practice used.

B. Mold or investment constituents used (wax, sand, etc.).

C. Number and position of items per mold.

D. Pouring temperatures used.

E. Mold cooling techniques used.

F. Gating and riser locations used.

G. Casting method used (permanent, mold, sand mold, centrifugal, etc.).

H. Mold temperature and control used.

I. Melting or casting atmosphere used (vacuum, inert gas, etc.).

J. Number and location of chill bars used.

K. Source and kind of row material used.

L. Post casting treatment used (chemical, mechanical, etc.).


7. Forging Process:

A. Forging Temperature used.

B. Number of and temperature of reheats used during forging.

C. Number of strikes or amount of reduction per strike and reheats.

D. Total percentage of reduction during the forging process.

E. Type of forging die used.

F. Forging method used (drop forge, pressure forge, ring rolling, etc.).

G. Cropping method used.

H. Billet size or shape used.

I. Source and / or process of ingot to billet conversion process used.

J. Die insulation and / or lubricant used.

K. Canning or blockdown process used.

L. Post forging treatment process used.

M. Forging press rate.


8. Heat Treatment and Surface Hardening Processes:

A. Preheat treat cleaning process used.

B. Preheat treat coating used.

C. Furnace preparation, atmosphere, and control used.

D. Furnace temperatures and / or time cycles used.

E. Heat treat sequence used.

F. Cooling cycles and / or cooling rates used.

G. Quenching media and control used.

H. Use and control of sub zero stabilization processes.


9. Peening Processes:

A. Type and size of media used.

B. Type of equipment used.

C. Control of peening parameters (pressure, nozzle size, impingement angle, etc.).

D. Almen strip placement for intensity control.


10. Electrochemical Machining Processes (Cavity Sinking, Drilling, Grinding, etc.):

A. Electrolyte and Electrode:

(1) Type and control of electrolyte used.

(2) Type of electrode used.

B. Operation

(1) Feed and speed rates used.

(2) Operating voltage limits and controls.

(3) Sequence of operations.

(4) Operation pressure of electrolyte.

(5) Electrolyte operation temperature limits.

(6) Sludge build-up rate and limits.


11. Electro-Discharge Machining (EDM):

A. Dielectric Fluid and Electrode:

(1) Type of dielectric fluid used.

(2) Type of electrode used.

B. Operation:

(1) Type of feed rate used (vibrating, rotating, pulsing, etc.).

(2) Voltage, frequency, polarity, wave shape, spark duration, and related

parameters used.

(3) Sludge build-up rate and limits.

(4) Control of dielectric fluid (temperature, contamination, etc.).


12. Electro-Stream Drilling (ESD):

A. Electrolyte:

(1) Type of and control of electrolyte used.

B. Operation:

(1) Feed rate used.

(2) Operating voltage and control parameters used.

(3) Tool design and/or nozzle diameter used.

(4) Sequence of operation.

(5) Electrolyte operating temperatures and pressures used.


13. Metal Electroplating Processes:

A. Plating parameters and control (voltage, current, agitation rate, etc.).

B. Solution makeup and control limits.

C. Pre and post plating processes (heating, chemical cleaning, etc.).

D. Use and evaluation of test specimens.

E. Stripping and re-plating procedures.

F. Anode and fixture control.


14. Protective Finishing Processes:

A. The application and control of:

(1) Hot Dip Coating

(2) Metal Spraying

(3) Oxide Coating

(4) Phosphate Coating

(5) Paints, Varnishes, Lacquers, Enamels

(6) Rust Inhibitors

(7) Ceramic Coatings

(8) Silicates

(9) Epoxies

(10) Plastics

B. Pre and post item treatment processes.

C. Coating testing procedures.

D. The control and thermal processes when used.

E. Stripping and recoating processes.


15. Metal Forming Processes:

A. Die control.

B. Pre-, in process, or post-heat treatment controls.

C. Process sequence.

D. Die lubricant used and control.


16. Stress-free Grinding Processes:

A. Speeds and feed used.

B. Type of abrasive used.

C. Type and control of coolant used.


17. Tooling:

A. Use of low melting point (high volatile) material where impurities could remain.

B. Equipment that could affect item properties such as dies, winding machines, etc.

C. Temporary tooling which could affect chemical, electrical, physical or mechanical

properties of the material.


18. Laser Drilling:

A. Maximum charge voltage or beam output energy.

B. Number of pulses per hole.

C. Internal packing material.


19. Process/Operation Sequence:

A. Process/operation sequence which, if changed or adjusted, could result in a change in the physical, chemical, electrical, or mechanical properties.


20. Composite Construction Processes:

A. Bonding Adhesives:

(1) Type of adhesive used.

(2) Adhesive application method used.

(3) Form of adhesive used.

(4) Source of adhesive supply.

(5) Type of adhesive primer used.

(6) Acceptance and re-qualification requirements.

(7) Storage control of adhesive (shelf life, storage temperature, etc.).

B. Bonding - Cleaning:

(1) Cleaning solution type, strength, time and temperature control.

(2) Pre and post cleaning item controls.

C. Bonding - Processing:

(1) Bond times, temperatures, pressure and atmosphere controls.

(2) Bond facility and controls (clean room, etc.).

(3) Item handling controls.

D. Bonding - Tooling:

(1) Tool configuration and control

(2) Tool qualification and re-qualification.


21. Manufacture of Metal Power Compacts:

A. Melting

B. Atomizing

C. Screening

D. Out-gassing

E. Blending

F. Transfer technique

G. Container filling

H. Preform manufacture

I. Filling procedures

J. Cleaning procedures

K. Hot isostatic pressing


22. Electrical Component Processes:

A. Coil winding

B. Molding

C. Potting

D. Swaging

E. Crimping and staking

F. Curing

G. Water-proofing

H. Insulating

I. Splicing


23.  Important Test Processes:

A.      Destructive and nondestructive tests

B.      Proof load test

C.      Pressure tests

D.      Leakage tests

E.      Tensile tests

F.      Operational tests

G.     Functional tests


24.  Additional Import Processes for Consideration:

A.  Stress relief

B.  Marking

C.  Fabrication

D.  Assembly

E.  Special packaging

F.  Special handling (i.e. electrostatic discharge)