BS M 78:1995 download.Aerospace – Aircraft de-icinglanti-icing non-Newtonian fluids , ISO type II.
1 Scope
BS M 78 establishes the requirements for non-Newtonian fluids used in the removal and prevention of frozen deposits of frost, ice and snow on exterior surfaces of parked aircraft.
It establishes the minimum requirements for an environmental test chamber and test procedure to carry out anti-icing performance tests according to the current materials specification for ISO type II aircraft de-icing/anti -icing non-Newtonian fluids.
WARNING — Products meeting the requirements of this International Standard can be adversely affected by mixing with other de-icing/anti-icing fluids.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of BS M 78. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on BS M 78 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 1518:1992. Paints and varnishes — Scratch test.
ISO 27 19:1988, Petroleum products and lubricants — Determination of flash point — Pensky-Martens closed cup method.
ISO 3013:1974, Aviation fuels — Determination of freezing point.
ISO 9002:1994, Quality systems — Model for quality assurance in production, installation and servicing. ISO 11076:1993. Aerospace — Aircraft de-icing/anti-icing methods with fluids. ISO 11077:1993. Aerospace — Self-propelled deicing/anti-icing vehicles — Function at requirements.
OECD. Guidelines for testing of chemicals.
Section 3— Degradation and Accumulation. Ready
Biodegradability, 301 D Closed Bottle Test.
AMS 2470H, Anodic Treat ment, Aluminium Alloys,
Chromic Acid Process2.
AMS 2475D, Protective Treatment, Magnesium Base
Alloys.
ASTM F 945-85. Test Met hod for Stress-corrosion of
Titanium Alloys by Aircraft Engine Cleaning
Materials.
ASTM F 1105-90, Test Method for Preparing
Aircraft Cleaning Compounds, Liquid Type, Solvent
Base, for Storage Stability Testing.
ASTM F 1110-90, Test Method for Sandwich corrosion Test.
ASTM F 1111-88, Test Method for corrosion of Low-Embrittling cadmium Plate by Aircraft Maintenance Chemicals.
MIL-A-8243D. Anti-Icing and De-Icing Defrosting Fluids.
MIL- P-833 10, Plastic Sheet, polvcarbonatc, t ransparen t4.
DIN 65321:1989, Aerospace; Acrylic sheets, panes and in oulded parts; Technical specification’. WL 5.14 16:1992, Aerospace; acrylic material, cast, crosslinked, in 5.1415 material, biaxially stretched and crack propagation, resistant.
3 Definitions
For the purposes of this International Standard, the following definitions apply.
3.1
non-Newtonian fluid
fluid whose viscosity is shear dependent and time dependent
3.2
pseudoplastic behaviour
decrease of viscosity with an increase in shear rate
3.3
all compound produced in a single production run from the same batches of raw materials under the same fixed conditions and presented for vendor’s inspection at one time
NOTE 1 The compound may be packaged in smaller quantities under the basic lot approval provided lot identification is maintained.
3.4
preproduction test
test to determine conformance to all technical requirements of this International Standard
3.5
acceptance test
test to determine conformance to the requirements given in 4.2.4, 4.2.8, 4.2.10 and 6.1
4.2.6 Thermal stability
4.2.6.1 The fluid, when subjected to a temperature of 70 °C (158 °F) for 30 d, in accordance with the test procedure described in 4.2.6.2 shall not show any insoluble deposit, any precipitation or severe turbidity. Further, the aged product shall not have a pH change of more than ± 0,5 from the initial value and the Brookfield viscosity at (20 ± 0,5) °C after the test shall neither he reduced by more than 20 % nor increased by more than 10 0%, compared with the initial value.
The fluid shall meet the criteria of the anti-icing performance tests specified in clause 9.
4.2.6.2 Determine the Brookfield viscosity of the sample in accordance with 6.1 at 20 °C (68 °F) and the pH value in accordance with 4.2.4 before starting the test.
Place 350 ml of the fluid to be tested in a jar of 500 ml equipped with a sealed cap. Place the sealed jar in the oven at7O°C±2°C(158°F±3,6°F)for30d.After removing and cooling the fluid, examine visually and compare with the non-aged control fluid. Measure the pH value and the Brookfield viscosity over the range of— 30 °C to + 20°C (— 22 °F to + 68 °F) and compare the results with the initial values.
4.2.7 I-lard water compatibility The fluid diluted 1 + 1 (by volume) with standard hard water (as specified in 4.2.7.1). when submitted to the stability test specified in 4.2.7.2, shall not show any insoluble deposit or increase in turbidity greater than the freshly made control sample diluted I + I (by volume) with ASTM D 1193 Type IV water. The pH value of the tested sample shall be within ± 0,5 of the initial value.
4.2.7.1 composition of standard hard water Dissolve 400 mg ± 5 mg of calcium acetate [(CHCOO)Ca.2H2OJ and 280 mg ± 5 mg of magnesium sulfate (MgSO4.7H20) in 11 of ASTM D 1193 Type IV water.
4.2.7.2 Stability test of diluted solution Heat 350 ml of the diluted fluid
at 95 °C ± 2 °C (203 °F ± 3,6 0F’) in a 500 ml glass jar fitted with a sealed cap or a water condenser for 30 d.
At the end of this period, perform a visual inspection and pH measurement and compare the results with those of the fresh sample.
5.3.2 The fluid, heated
to 65 °C ± 2 °C (149 °F ± 3,6 °F’) and applied to a painted surface having an initial surface temperature of 22°C (71,6 °F) shall not produce any streaking, discoloration, or blistering of the paint film, determined in accordance with ASTM
F 502.
5.4 Effect on upainted surfaces
The fluid, tested in accordance with ASTM F 485, shall neither produce streaking nor leave any stain requiring polishing to remove.
6 Rheological properties
The fluid shall exhibit non-Newtonian flow behaviour. Over the temperature range — 30 °C to + 20 °C (22 °F to + 68 °F), the fluid shall exhibit pseudoplastic behaviour determined in accordance with ASTM D 2196.
NOTE 2 ISO type II fluids containing pseudoplastic thickeners provide protection against the buildup of frozen deposits.
6.1 Viscosity
For quality control purposes, the manufacturer shall report the typical viscosity values, measured in accordance with ASTM D 2196 and expressed in millipascal seconds (mPa s), for its qualified product.
The measurements shall be carried out using a Brookfield type LVT viscometer with Nos. 1 and 2 spindles or an SC 4-34/13 R small sample adaptor.
The measurements shall be carried out at rotation speeds of 0,3 min’, 6 mm ‘and 30 min’.
The temperatures at which the measurements are made and the spindle number shall also be reported.
NOTE 3 The number (type) of the applied spindle should be in accordance with the recommendations of the viscometer manufacturer.
The viscosity of the delivered fluid shall be within ± 10% of the typical values.
6.2 Shear stability
The anti-icing performance requirements specified in Annex A shall be met after the product is pumped and sprayed with industrial spray equipment, in accordance with ISO 11077, used for de-icing/anti-icing of aircraft.
6.2.1 The following laboratory test has been found suitable for simulating the shear effect of several types of industrial spray equipment.
11 Quality assurance provisions
11.1 Responsibility for inspection The vendor of the product shall supply all samples for vendors tests and shall be responsible for performing all required tests. Results of such tests shall be reported to the purchaser as specified in 11.5.
The purchaser reserves the right to sample and to perform any confirmation testing deemed necessary to ensure that the product conforms to the requirements of this International Standard.
11.2 Frequency of testing
11.2.1 Prep roduction tests
Preproduction tests shall be performed;
a) prior to initial shipment of the product to a purchaser;
b) when a change in material, processing or both requires reapproval as in 11.4.2:
c) when the purchaser deems confirmation testing to be necessary.
11.2.2 Periodic tests
Periodic tests shall be performed biannually.
11.2.3 Acceptance tests
Acceptance tests shall be performed on each lot.
11.3 Sampling
11.3.1 Preproduction and periodic tests Sufficent product from a single production lot shall be taken at random to perform all required tests.
11.3.2 Acceptance tests
Sufficient product shall be taken at random from each lot to perform all required tests.
11.4 Approval
11.4.1 The preproduction compound shall be approved by the purchaser before fluid for production use is supplied. Result of tests on production fluid shall be essentially equivalent to those on the approved sample fluid.
11.4.2 The vendor shall use ingredients, manufacturing procedures and methods of inspection on the production fluid which are essentially the same as those used on the approved preproduction sample. If necessary to make changes in ingredients, formulation or manufacturing procedures, the vendor shall submit for reapproval a statement of proposed changes. The results of retesting for anti-icing and aerodynamic performance as specified in clauses 9 and 10 respectively as well as those for any other test deemed necessary by the purchaser shall also be submitted.