Capítulo 3. Procedimiento para Realizar una AI en el Polo PetroSoft y Validación General
3.10 Conclusiones Parciales
AC7102/2 includes questions specific to conductivity testing; however, no separate approval for conductivity testing will be listed on supplier Nadcap certifications.
If Customer specifications do not give guidance, Supplier procedures shall specify allowable tolerance of acceptance for calibrations. It is not expected that calibration on shop floor standards will exactly meet values on the block; however, the allowed deviation must be proceduralized and the operator shall be aware of the allowance.
Do procedures reference compliance to ASTM E 1004 or MIL-STD-1537?
Do procedures reference that the conductivity test equipment shall require a periodic standardization every hour of continuous operation?
Do procedures state that equipment which does not provide accurate or repeatable results shall be corrected and recalibrated?
Does the inspection source report show the actual minimum and maximum values obtained?
It is assumed that the Conductivity and Hardness testing specification flowed down in AMS 2770 is AMS 2658 and it is the only testing specification mentioned in AMS 2770. AMS 2770H, Section 4.3, does not directly flow down any Conductivity and Hardness testing specification except for 4.3.1.2 for 6XXXX alloys and 4.3.3 under Failures. It is apparent that this was an oversight and will be corrected at the next revision of AMS 2770. In the interim, AMS 2658 will be considered the Conductivity and Hardness testing
specification flowed down by AMS 2770, in the absence of any other direction by customer purchase order or contract.
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APPENDIX A: ALUMINUM SPECIFICATIONS
Commodity: Aluminum Prime: Alenia Aeronautica SpA
Governing Specification: NTA 71250 (parts)
NTA 71251 & NTA 71252 (rivets) Allowable Specifications:
AMS 2770, AMS 2771 (as applicable to the most current revision).
Requirements:
Pyrometry: NTA 98252
Process Control Tests: Monthly - HTO, IGC, Eutectic Melting, Clad Diffusion & Tensile:
• tensile (9 specimens symmetrically distributed within the working zone),
• susceptibility to intergranular corrosion (1 test carried out on the specimen with the lowest tensile yield strength),
• eutectic melting and high temperature oxidation (1 test carried out on the specimen with the lowest % elongation),
• diffusion of alloying elements in the cladding
Load T/C: Not required
Load Verification: Hardness and conductivity inspection
Hardness Testing: Required on at least 10% of parts for every load (to be performed on parts with minimum and maximum value of conductivity) or 100% if conductivity testing is not carried out (6xxx alloys)., Test per NTA 95051
Conductivity Testing: Required at 100% with registration of minimum and maximum values for each work order. Test per NTA 94551
Tensile Testing: Required for 7050-T74 forgings, extrusions and plates; 7075-T76xx sheets, extrusions and plates; 7475-T76xx sheets
Test per ASTM B 557
Commodity: Aluminum
Prime: Bell Helicopter Textron Governing Specification: BPS 4139
Allowable Specifications: none Requirements:
Pyrometry: AMS 2750
Purging compounds: 2000 and 7000 series, ammonium fluoborate, BPS 4139, par 2.2.1.2 Polymer Quenchants: composition IAW AMS 3025, Type I, no mixing of glycol manufacturers,
maximum salt contamination, par 2.3.7 and Table 8.
Salt Bath Salts: MIL-S-10699, Class 2 with slight modifications, par 2.2.2 Quenchability Tests: Monthly on all solution heat treat furnaces, par 5.1.6
Load T/C: Not required
Load Verification: Alloy dependent, par 6.2.3
Hardness Testing: Conditional on all parts as a substitute for tensile testing except for alloys listed below. Test per BPS 4467
Tensile Testing: All 7XXX series. Test per ASTM B557
HEAT TREATING TASK GROUP AUDIT HANDBOOK
Commodity: Aluminum
Prime: Cessna Aircraft Company
Governing Specification: CSMP003 – Heat Treatment of Aluminum
CSMP004 – Heat Treatment & Surface Enhancement of Steels (Includes Stainless Steels and Carburizing)
CSMP010 – Heat Treatment of Nickel-Based Alloys
CSMP047 – Heat Treatment of Titanium and Titanium Alloys Allowable Specifications: SEE BELOW
Requirements:
If the Auditor sees a Cessna drawing or parts where Cessna is identified as the Prime; the Auditor can assume that the above four specs will apply. How that conclusion is reached is very complicated. We may flow down the above specs on outside process specification sheets (OPSS) that state the processes we know have to be performed, but just because OPSS does not cover a heat treat spec doesn’t mean it’s not required.
All Cessna designed parts have a note on the drawing in the tolerance block that says “Process per CSPS004”.
That spec defines all processes that if performed are required to be performed per a Cessna spec. To our engineers, they don’t care if you use a process or not when they design a part, but if you do and its one we want controlled we want you to control it to our spec. It’s confusing, that’s why its safe to assume that if it is a Cessna part, Cessna heat treat specs apply.
The other key issue is our limitations on industry heat treating specs. We do allow suppliers to use either our heat treating spec or industry specs in-part or in-full within a series of exceptions. For example, a heat treater working to CSMP003 can use the times and temperatures from AMS 2770. There are limitations on the extent a Supplier can use the industry spec.
For all four of the Cessna specs listed above, the exceptions to industry standards are listed in
Paragraph 9.0 (found on the last page of each document). While each alloy group has their own exceptions, the key exceptions are:
• Quality and Testing must be per the Cessna Spec (all items covered in Para 7.0) including all periodic testing listed
• Pyrometry is our spec, which states per AMS2750 with minor exceptions (e.g. aluminum solution treat must recover to low end of tolerance within 30 minutes)
We bring this issue up as some Suppliers are stating that they can run completely to industry specs if we call out CSMP003, which has more testing required.
HEAT TREATING TASK GROUP AUDIT HANDBOOK
Commodity: Aluminum
Prime: Goodrich Aerostructures Governing Specification: RPS 12.31
Requirements:
Pyrometry: AMS 2750
Protective Compounds: Ammonium or sodium fluoborate per RPS 12.31 par 3.2.3.
Polymer Quenchants: Compliant with AMS 3025, no mixing of Types I & II allowed.
Salt Bath Salts: Compliant with Mil-S-10699, Class 2, test for Mg conc. if Al-Mg alloys used; test quench/rinse media for salt/TDS as applicable per RPS 12.31 par 3.6.
Quenchability Tests: Glycol concentration – test per RPS 12.31 par 4.7.7 & 4.7.8.
Quenchant temperature - maintain per RPS 12.31 par 3.15.1.
Monthly – HTO, Eutectic Melting, IGA/Corrosion, Clad Diffusion and Mechanical Properties per RPS 12.31 par 4.7.6.
Load T/C: Not required.
Load Verification: Hardness and conductivity inspection per RPS 18.11, tensile test as noted, per ASTM B557.
Refrigeration Control: Required per RPS 14.05.
Hardness Testing: Required on 100% of parts on 7000 series heat treated to T7XXXX tempers;
required on 10% of parts on other aluminum alloys; except not required on perforated skin.
Tensile Testing: Required on each lot of alloy 7050 (also for monthly controls, as above).
Conductivity Testing: Required on 100% of parts on all alloys.
Commodity: Aluminum
Prime: Vought Aircraft Industries, Inc.
Governing Specification: 208-2-7 Rev. E Allowable Specifications:
208-2-7 allows suppliers to use AMS 2770, AMS 2771, & AMS 2772 (as applicable to the most current revision).
Requirements:
Pyrometry: AMS 2750
Polymer Quenchants: Compliant with AMS 3025 Salt Bath Salts: Compliant with MIL-S-10699
Quenchability Tests: Weekly – Glycol viscosity – Test per ASTM D 445
Monthly - HTO, IGC, Eutectic Melting, Clad Diffusion & Tensile
Load T/C: Not required
Load Verification: Hardness and conductivity inspection
Hardness Testing: Required on at least 10% of parts for every load or 100% if conductivity testing is 10%, except for 7000 series in T7XXX.. For 7000 series in T7XXX – 100%
hardness inspection. Test per 208-14-16.
Tensile Testing: Each load of 7050T7XX & 7075 forgings quenched in glycol only–
HEAT TREATING TASK GROUP AUDIT HANDBOOK
Aluminum Specifications
Commodity: Aluminum
Prime: SONACA
Governing Prime Specification: PS 6.4001 Allowable industry Specifications: None Requirements:
Pyrometry: AMS 2750
Polymer Quenchants: Compliant with AMS 3025 Salt Bath Salts: Not accepted
Quenchability Tests: Weekly and quarterly – Glycol concentration – test per PS 6.4001 par 3.4 Monthly – HTO, IGC, Eutectic Melting, Clad diffusion and Tensile – Test per PS 6.4001 par 6.1
Load T/C: Not required
Load Verification: Hardness and conductivity inspection per PS 6.8003
Hardness Testing: Not required except for 6000 series - 100 % hardness inspection – Test per PS 6.8002
Tensile Testing: Not required on parts (only for monthly controls per ASTM B557) Conductivity Testing: Required on all alloys on 100 % of parts - Test per PS 6.8001
HEAT TREATING TASK GROUP AUDIT HANDBOOK
APPENDIX B: PRIME SPECIFICATION MATRIX
Alloy Specific Heat Treat Specifications
Prime Aluminum HT Steel HT Nickel-Based HT Titanium HT Magnesium
HT Pyrometry
Airbus (UK) ABP3-1119 ABP3-1116
ABP3-1115 ABP3-1115 ABP3-1117 N/A BS M54
Airbus (Germany) 80-T-36-1010 36-1020
80-T-36-3300 N/A 80-T-36-1015
80-T-36-3400 N/A
QVA-Z-09-10-00 QVA-Z-09-13-00 QVA-Z-09-14-00 Airbus (France) IPDA61-01 IPDA61-03 IPDA61-03 IPDA61-03 N/A IGC 04.63.100
IGC 04.63.105
ASNA written on the drawing
Germany EI045 36-1010
EI045 80-E-36-1020
HEAT TREATING TASK GROUP AUDIT HANDBOOK PRIME SPECIFICATION MATRIX-continued
Prime Aluminum HT Steel HT Nickel-Based HT Titanium HT Magnesium
HT Pyrometry
Rolls-Royce Plc RPS953, RPS654
RPS953, RPS258, RPS356, RPS360, RPS394, RPS765
RPS953, RPS574 RPS953,
RPS323 N/A RPS953
Industries, Inc. 208-2-7
CVA 1-372
Honeywell E, S, &S AMS2770, AMS2771,
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Other Specifications
Prime Brazing Carburizing Nitriding Hardness Tensile Conductivity
Airbus (UK) N/A ABP3-1111 ABP3-1113 ABP6-5226 BS4A4 ASTME8 ABP6-5226
Airbus
(Germany) N/A 80-T-36-3001
80-T-36-3201
CSMP009 CSMP004 CSMP004 CSTI028
ASTM E8 or
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Other Specifications - continued
Prime Brazing Carburizing Nitriding Hardness Tensile Conductivity
Northrop Grumman
W-26 W-25 W-27
H-107
H-113 HT-4 MIL-N-22061 SAE-AMS-S-6090
H-107 H-113 HT-4 MIL-N-22061 SAE-AMS-S-6090
N/A FED-STD-151 N/A
Rolls-Royce
Plc RPS371 RPS135 MSRR9969 MSRR9968
MSRR9922 BS L100 EN2004-1
Rolls-Royce Corporation
RPS 194 & RPS 953
EPS 200 EPS 206 EPS 214 EPS 215 EPS 216 EPS 222
EPS 227 EPS 270 EPS 271 EPS 272 EPS 292
ASTM E 18
N/A N/A
Sikorsky Aircraft
AWS C3.4 AWS C3.5 AWS C3.6 AWS C3.7
SS8015 N/A ASTM E 18
ASTM E 384 ASTM E 8 MIL-STD-1537B(1) AMS 2658
SONACA N/A PS 6.4150 N/A PS 6.8002
ASTM B557 ASTM A370
ASTM E8 PS 6.8001
Vought Aircraft Industries, Inc.
N/A N/A N/A 208-14-26 N/A 208-14-14
HEAT TREATING TASK GROUP AUDIT HANDBOOK
APPENDIX C: AMS 2750 VS RPS 953 Comparison Chart
Requirement AMS 2750 Rev D RPS 953 Issue 12
ELECTRONIC RECORDS Clause 3.2.7 As AMS clause 3.2.7 with the addition that back up records are made and retained in a separate location, ref. RPS953 2.3.3.1.
RECORD RETENTION Clause 3.7.1 (5
years minimum) As AMS clause 3.7.1 modified by RPS900, ref. RPS953 2.3.1 WIRE ROLL CALIBRATION Clause 3.1.1.6 As AMS clause 3.1.1.6 except that rolls <305 meters (1000 feet)
must also be calibrated at each end, ref. RPS953 2.8.
OVERTEMPERATURE SENSORS (Load Protect) a. aluminum/
magnesium materials
Offset not
defined in Rev D For load protect and set at +10C to set point, ref. RPS953 4.2.2.
b. others Offset not
defined in Rev D For load protect and set at +20C to set point, ref. RPS953 4.2.2.
TEMPERATURE UNIFORMITY TEST FREQUENCY
As clause 3.2.5 and Table 8 and 9
AMS clause 3.2.5 & Table 8, except that for Class 2 furnaces relaxation is to semi annually. Note that RR don’t accept the classification ‘Raw Material’ furnaces (Table 9), ref. RPS953 4.3.4.
TEMPERATURE UNIFORMITY SURVEY
Spread Acceptance Levels As clause 3.3.1
• For < 750 C require Class 2 furnace, i.e. +/- 6 C.
• For ≥ 750 C require Class 4 furnace, i.e. +/- 10 C.
• For vacuum furnaces ≥ 500 C require Class 4, i.e. +/- 10 C.
Ref. RPS953 4.3.3
As clause 3.5.6
As AMS clause 3.5.6 except that for Class 2 furnaces surveys shall be carried out at the highest and lowest temperature and
intermediate temperatures such that the range is no greater than 400 C, ref. RPS953 4.3.4. accept the classification of ‘Raw Material’ furnaces (Table 7), ref.
RPS953 2.8 & 4.4.
FURNACE ACCURACY CHECKS
As clause 3.4 and Tables 6 and 7.
As AMS clause 3.4 and Table 6. Note that RR don’t accept the classification of ‘Raw Material’ furnaces (Table 7), ref. RPS953 2.8 &
4.4.
Note:
1. Rolls Royce RPS 953 Section 4.3.2 requires that all furnaces shall have a minimum of one recording thermocouple for every one cubic meter up to a maximum of 5 cubic meters and there after the number shall be agreed with Rolls-Royce.
2. Rolls Royce RPS 953 Section 4.3.3 Note 2 states that none-critical heat treatments such as annealing (unless the final heat treatment) pre-heating prior to hardening, homogenizing, normalizing or stress relieving (where the stress relief is at least 50 deg C (90 F) below the final transformation temperature) with agreement from Rolls-Royce are not considered as Thermal Process (Heat Treatment) furnaces and will not therefore require Nadcap approval. This also applies to ovens used for drying or fitting, which also don’t require Nadcap approval.
HEAT TREATING TASK GROUP AUDIT HANDBOOK
APPENDIX D: AMS Heat Treating Specification – Start of Soak Time Recommendations Spec Description Existing Start of Soak Method Suggested Start of Soak
Method and HTTG approach
Comments
Soaking shall commence when all control, indicating, and recording thermocouples reach the specified set temperature or, if load thermocouples as defined in AMS 2759 are used, when the part temperature reaches the minimum of the furnace uniformity tolerance at the set temperature.
Control thermocouple(s) within 5°F of setpoint and all other recording or indicating thermocouples reach the minimum of the required temperature uniformity tolerance at the set temperature.
Load T/C portion can remain as is.
Needs to be revised
2759/2D HT of Steel ≥ 220 KSI
Soaking shall commence when all control, indicating, and recording thermocouples reach the specified set temperature or, if load thermocouples as defined in AMS 2759 are used, when the part temperature reaches the minimum of the furnace uniformity tolerance at the set temperature.
Control thermocouple(s) within 5°F of setpoint and all other recording or indicating thermocouples reach the minimum of the required temperature uniformity tolerance at the set temperature.
Load T/C portion can remain as is.
Needs to be revised
2759/3D HT of PH CRES
Steel Soaking shall commence when all control, indicating, and recording thermocouples reach the specified set temperature or if load
thermocouples, as defined in AMS 2759, are used, when the part temperature reaches the minimum of the furnace uniformity at the set temperature.
Currently under revision @
AMEC Current proposal requires
control T/C within 5°F and other furnace indicating or recording T/C’s must reach the minimum of the uniformity tolerance.
2759/4B HT of Austenitic CRES
Soaking shall commence when all control, indicating, and recording thermocouples reach the specified set temperature or, if load thermocouples as defined in AMS 2759 are used, when the part temperature reaches the minimum of the furnace uniformity at the set temperature.
Control thermocouple(s) within 5°F of setpoint and all other recording or indicating thermocouples reach the minimum of the required temperature uniformity tolerance at the set temperature.
Load T/C portion can remain as is.
Needs to be revised
2759/5D HT of Martensitic CRES
Soaking shall commence when all control, indicating, and recording thermocouples reach the specified set temperature or if load
thermocouples, as defined in AMS 2759, are used, when the part temperature reaches the minimum of the furnace uniformity at the set temperature.
Control thermocouple(s) within 5°F of setpoint and all other recording or indicating thermocouples reach the minimum of the required temperature uniformity tolerance at the set temperature.
Load T/C portion can remain as is.
Needs to be revised
2759/6B Gas Nitriding N/A
The load shall be held at nitriding temperature(s) in partially
dissociated ammonia atmosphere for sufficient time to produce the specified depth of case.
Supplier needs to identify in their internal procedure the defined method of start of the soak.
Start of soak method must be defined in the internal procedure.
HEAT TREATING TASK GROUP AUDIT HANDBOOK
APPENDIX D: AMS Heat Treating Specification – Start of Soak Time Recommendations (Contd) Spec Description Existing Start of Soak Method Suggested Start of Soak
Method and HTTG approach
Comments
2759/7A Carburizing The charge shall be held within the specified temperature range for sufficient time for necessary diffusion and transformation to take place. The holding time intervals shown in Table 3 are suggested times starting when furnace control instruments reach set temperature or when the lowest load thermocouple reaches the lower limit of the required temperature range.
Supplier needs to identify in their internal procedure the defined method of start of the soak.
Start of soak method must be defined in the internal procedure.
2759/10A Automated Gas Nitriding (N2 Potential)
N/A Supplier needs to identify in
their internal procedure the defined method of start of the soak.
Start of soak method must be defined in the internal procedure.
2759/11 Stress Relief Soaking time starts when all temperature sensors are within 25
°F (14 °C) of the specified
N/A Supplier needs to identify in
their internal procedure the defined method of start of the soak.
Start of soak method must be defined in the internal procedure.
2769A Vacuum Heat
Treatment Load Thermocouples (or Initial Load Qualification with Load Thermocouples) is required. Start of Soak would revert to the referenced heat treating specification.
Supplier needs to identify in their internal procedure the defined method of start of the soak and meet all the customer requirements.
N/A
2770H HT of Aluminum Parts 3.2.5.1 - Soaking time starts when all temperature control sensors reach the minimum of the uniformity tolerance range specified in 3.1.1.1, 3.1.1.2, or 3.1.1.3, as applicable. Load sensors should not be used to determine start of soaking time. This is modified by Table 3, Note 2 for Solution Heat Treating - Soaking time starts when all thermocouples are within 10 °F (6 °C) degrees of the set temperature; and by Table 8, Note 2 for Annealing - Soaking time starts when all thermocouples are within temperature range indicated.
Soaking time starts when all control, recording, and monitoring sensorsreach the minimum of the uniformity tolerance range specified in 3.1.1.1, 3.1.1.2, or 3.1.1.3, as applicable. Load sensors should not be used to determine start of soaking time.
This is wording that was agreed upon at the 10/2009 AMEC meeting for inclusion in the next revision. Note: The specification says that,
"Load sensors should not be used to determine start of soaking time.", but does not prohibit the use of load sensors for determining start of soak.
Start of soak method must be defined in the internal procedure.
2771C HT of Aluminum Castings
Soaking: Soaking time starts when all temperature control sensing elements and load thermocouples (if used) are within 10 °F (6 °C) of the set or offset temperature.
No change necessary. N/A
HEAT TREATING TASK GROUP AUDIT HANDBOOK
APPENDIX D: AMS Heat Treating Specification – Start of Soak Time Recommendations (Contd) Spec Description Existing Start of Soak Method Suggested Start of Soak
Method and HTTG approach
Comments 2772D HT of Aluminum
Raw Material
Solution Treatment:
Soaking time shall start when the readings of all load sensors indicate that the temperature of the load has reached the minimum of the required temperature range. Alternatively, determination that the temperature of the load has reached the minimum of the required temperature range (start of soaking time) may be based on readings of furnace instruments providing the lag between their readings and load temperature has been determined in a similarly arranged load.
Aging:
Times are recommended
No change necessary. N/A
2773A HT – Cast Nickel Alloy & Cobalt Alloy Parts
Batch Furnaces: Soaking time starts when all furnace temperature sensors reach the specified set or offset temperature or, if load
thermocouples are used, when the coldest load thermocouple reaches the required temperature minus the appropriate tolerance.
Vacuum Furnace: Unless otherwise specified by the cognizant
engineering organization, load thermocouples shall be used to determine the start of soaking time except when this is impractical, such as with two or three chamber oil or gas quench furnaces, in which case tests shall be conducted to establish the correct heat-up time for the load.
Once a load has been qualified with load thermocouples, subsequent loads may be run without load thermocouples provided records detailing the number of parts in the first qualified load are kept on file, and provided that subsequent loads have an equal or fewer number of similar parts in the load, and the distribution of the parts is the same as the distribution in the first load.
Batch Furnaces:
Control thermocouple(s) within 5°F of setpoint and all other recording or indicating thermocouples reach the minimum of the required temperature uniformity tolerance at the set temperature.
Load T/C portion can remain as is.
Needs to be revised
HEAT TREATING TASK GROUP AUDIT HANDBOOK
APPENDIX D: AMS Heat Treating Specification – Start of Soak Time Recommendations (Contd)
APPENDIX D: AMS Heat Treating Specification – Start of Soak Time Recommendations (Contd)