NES M0140 2004N Salt Spray Testing(ENG)盐雾测试标准.pdf

M0140 2004-N - 1/9 - Nissan Engineering Standard N E S Salt Spray Testing 1. SCOPE This Standard specifies corrosive salt spray tests for plated or painted metals used for anti-corrosive and decorative purposes on automobiles. Remarks: 1. Classification of test objects. (1) Metal covered with metallic, inorganic or organic film.metal plating, painting, resin coating, etc. (2) Metallic film and inorganic film applied to non-metal.metal plating, vacuum plating, hot stamp, etc. on resin. (3) Metal.stainless steel, aluminum alloy, titanium alloy, etc. 2. The units and numerical values expressed in this standard are based on SI units. Conventional units are noted in for informative reference. 2. TEST EQUIPMENT The pieces of test equipment consist of a temperature controlled chamber, test solution chamber, test so- lution supply tank, air saturator, air compressor, and exhaust fan equipped with the following: spray noz- zles, test piece holder and spray collecting container. An example of the test equipment is shown in Fig- ures 1 and 2 and shall satisfy the following conditions. (1) The materials used for the pieces of equipment shall not influence the results of the corrosion test and shall not corrode themselves during the test. (2) Do not direct the spray nozzle and spray test liquid directly on to the test pieces. Drops of the test solution, condensed on the ceiling or cover of the test chamber, shall be prevented from falling on the test samples. (3) Drops of test solution that fall from the test samples shall not be reused for another test. (4) The spray collecting containers must be clean and have a collecting area of 100 mm diameter and each have a horizontal collecting area of approximately 80 cm2. They are placed adjacent to the test pieces at more than two positions to provide uniform spray pattern: nearest to and furthest from the spray nozzles. (5) The compressed air for spraying the test solution shall not contain oil or dust. 3. TEST LIQUIDS AND SPRAY CONDITIONS (1) Water used for test solution.Deionized water (252C specific resistance: 1 S/cm or less). (2) Sodium chloride used for test solution Former JIS K 8150 (Sodium chloride Class 1) or above. (3) Concentration of test solution505 g/L (4) Specific gravity of test solution1.029 to 1.036 (252C) (5) pH of test solution .6.5 to 7.2 (252C) (6) Spraying pressure of test solution.0.07 to 0.17 MPa 0.0980.010 MPa 1.00.1 kgf/cm2 is preferable (7) Spraying rate of test solution.1.50.5 m/80 cm2/h (8) Temperature of the test chamber352C (9) Temperature of the test solution chamber.352C (10) Temperature of the air saturator472C *1) Standard values by former JIS K 8150-1989 (Sodium chloride class 1) are shown as follows. Item Standard value Water solubility Within the limit pH value (5W/V%) 5.0 to 8.0 Sulphate (SO4) max. 0.005 % Heavy metal (as Pb) max. 0.001 % Potassium (K) max. 0.01 % Magnesium (Mg) max. 0.003 % Calcium (Ca) max. 0.003 % Barium (Ba) max. 0.001 % Iron (Fe) max. 0.0005 % Ingredient min. 99.0 % Normative References: JIS K 8150-1994 Sodium chloride References: ISO 9227-1990 Corrosion tests in artficical atmospheres-Salt spray tests JIS H 8502-1999 Methods of corrosion resistance test for metallic coatings JIS Z 2371-2000 Methods of salt spray testing M0140 2004-N - 2 - 4. CONTROL STANDARD FOR THE TEST EQUIPMENT AND TEST SOLUTION According to the Attachment: Procedure for Producing Salt Spray Test Solution and Control Standard for The Test Equipment 5. TEST PIECES 5.1 Test pieces shall be the product itself or a portion of the product that includes the effective surface area. If it is difficult to use the product for the test or if test results are not conclusive, then alternative test pieces may be used to represent the product. 5.2 Shape, dimensions, and number of test pieces shall conform to the specifications of the test material or product standard. However, if standard specifications are not available, agreement must be reached between the parties concerned. 5.3 Pretreatment of test pieces 5.3.1 Cleaning of test pieces (1) Completely clean test pieces of metal for metal film using a suitable cleaning agent (1) such as ethyl alcohol or other cleaner. Note (1): No polishing, corrosive or protective film-creating cleaning agent shall be used. (2) For chromium plated test pieces, the test surface may be cleaned by rubbing with absorbent cotton wetted with water and magnesium oxide powder or precipitating calcium carbonate; washed with water and cleaned with a clean cloth or blotting paper. (3) Test pieces painted or covered with a non-metallic film shall generally not be cleaned or treated before the test. 5.3.2 Cross-cutting of test pieces When corrosion of a painted or organic coating is to be measured, the paint or film shall be cut in a cross shape to within 10 mm of the edges of the test piece using a sharp, thin blade until it reaches to the base material. 5.3.3 Protection of surface other than the test area of test pieces Cut sections, exposed base and edges, etc. of the test pieces that are not part of the test surface shall be covered with protective coating(2). This protective coating shall be stable under the test conditions. Note (2): Cover with electrical insulation tape or solid paraffin. 5.4 Supporting test pieces During the test, test pieces shall be placed in the test chamber in the following manner. (1) The important test surface shall be inclined at an angle of 20 (allowable range: 15 to 30) to the vertical and parallel to the direction of the important flow of the spray viewed from test chamber top. (2) Test piece shall not prevent free-fall of the atomized test solution. (3) Test pieces shall not be in contact with anything other than the supporting frame. (4) The test solution of a test piece shall not splash on another test piece. (5) Punched identification marks, mounting holes, etc. of the test piece shall be placed as close as possible to the bottom. 5.5 Treatment of test pieces after spraying After spraying, the cover of the test chamber is opened carefully to prevent falling drops of the salt solu- tion from hitting the test pieces. Take out the test pieces carefully so as not to damage the test effective surfaces. The test pieces must then be immediately immersed in room temperature water (to rinse off salt adhering to surfaces) and dried. If specifically required, lightly brush to inspect the corrosion of the base metal. 6. PROCEDURES Follow the steps below for the operation. The procedures for production method of the test solution are shown in the Attachment. (1) Fill the prepared test solution in the salt water and supply chambers. (2) Adjust the spray pressure indicated on the precision pressure gauge to 0.0980.010 MPa 1.00.1 kgf/cm2, and collected spraying rate of test solution to 1.50.5 m/80 cm2/h by operating the pressure regulator. Spray volume, if difficult to adjust within the above pressure range, may be adjusted by changing the spray pressure in the range of 0.07 to 0.17 MPa. (3) Visually confirm that the spraying is correctly conducted. (4) Adjust the temperature of the test chamber and the salt water chamber to 352C and the temperature of the air saturator to 472C. M0140 2004-N - 3 - (5) Interrupt spray and place the test pieces on the test piece holder inside the chamber. (6) To start the test, restart the spraying. Spray for the specified time and under the specified test conditions. (7) Environmental variations (salt spraying rate, variations in temperature) occur within the tolerance of specified value, due to the difference in installation position of test piece under the range of conditions indicated in Item 3 in the test solution and spraying condition. Therefore, as a measure for reducing such variations, rotation of the test piece is required. However, regarding the rotation method and its frequency, and other details, they shall be de- termined through the consultation between the concerned parties, after considering the required accuracy for the test. See the following cases as examples for performing the rotation: For the test period of 2 weeks or more Move the test piece any number of times (recommended to perform in the frequency of once per week or more) during the test period, by an installed unit or by a unit of installed row. For example, if there are 4 installed units, number them 1 to 4 beforehand, and perform the moving of the installed units in the order of: 12341 on a weekly basis. For the test period of 2 weeks or less Since the number of rotations will be smaller, perform the test within the range of the median value 1.50.1 m/8.0 cm2/h (specified value: 1.50.5 m/8.0 cm2/h) for the spraying rate specified in 16. Spraying rate of the Attachment Table 1. For securing the accuracy by long-term test For the purpose of improving the test accuracy, the following describes the examples of the procedure for com- plete randomization of the rotation order: (1) Number nonnegative integers 1 to n for each test piece number n. (2) Generate random numbers of nonnegative integers 1 to n for the n installation positions for test pieces. (3) Install test pieces to each position, according to the numbers that are identical with the installation position numbers for test pieces. (4) Perform the rotation of the test piece by repeating (2) and (3) described above any number of times (recom- mended to perform in the frequency of once per week or more) during the test period. (8) After the specified time, remove the test pieces cautiously so as not to damage the test effective surfaces. 7. TEST TIME Test time is as specified in the material standard or the product standard. 8. CONTINUATION OF THE TEST The test must not be interrupted. Remarks: 1. Test pieces must be rinsed well with distilled water and kept dry when the test is unavoidably inter- rupted. 2. During the test, interruption must be done within the shortest period of time due to inspection of test samples, examination of the test solution or supply of the solution. 3. Continuous test means continuous operation of the test equipment while keeping the cover of the test chamber closed except for the interruption of test as specified in 2. 9. EVALUATION OF RESULTS The results are evaluated on the basis of the material standard, the product standard, or determined by the agreement between the parties concerned. 10. REPORT Record, unless otherwise specified by the material standard or the product standard, the following items: (1) Types of sodium chloride and water used for preparing the test solution (2) Measured temperature of the spraying area in the test chamber (3) Daily recorded values of the following items obtained from each collecting container (a) The volume (m) of the test solution collected per hour per 80 cm2 (b) The concentration or the specific gravity at 25C of the solution in the collecting container (c) pH of the solution in the collecting container (d) Shape, dimension, and part number or classification of the test pieces (e) Test piece rinsing method before and after the test (f) Method of holding test pieces in the test chamber (g) Type of protective coating used according to 4.3.3 (h) Spraying time (i) Reasons for test cancellation and test time before cancellation (j) Final inspection results M0140 2004-N - 4 - Figure 1 Salt spray test setup Temperature regulator Test chamber Thermometer Vent tube Sample Exhaust Thermal insulating plate Separator Drain Collecting container Thermometer Test chamber heater Test liquid supply bottle Temperature regulator Thermometer Air saturator Air cleaner Pressure gange Pressure regulator Compressed air Distribution panel Spray nozzle Nozzle bypass valve Test liquid tank Nozzle air valve Thermometer for temperature saturator Air saturator heater Dry and wet bulb Test liquid tank heater M0140 2004-N - 5 - Figure 2 Test chamber Front view Side view 1,040 M0140 2004-N - 6 - Attachment: Procedure for Producing Salt Spray Test Solution and Control Standard for The Test Equipment. 1. Procedure for producing salt spray test solution (1) Use sodium chloride (NaCl) reagent Class 1 or superior as specified in former JIS K 8150-1989 (Sodium chloride Class 1). (2) Use deionized water (specific resistance: 1 S/cm or less). (3) Prepare a plastic container (approximately 50), wash the container with tap water and finally rinse the same with deionized water. (4) Fill 40 of deionized water in the container. (5) Heat the water up to 25C with an immersion quartz heater (about 1 kW) stirring occasionally with a plastic or glass stirrer to blend the temperature evenly. (6) Dissolve sodium chloride (NaCl) in a concentration of 50 g per liter of solution. (7) After stirring the solution sufficiently, measure the specific gravity of the solution at 25C. Adjust the specific grav- ity to 1.029 to 1.036. (8) Next, sample 50 m of the solution and measure its pH using a glass electrode type pH meter. With a pH of 6.5 or less at 25C, add a thin solution of sodium hydroxide, completely stir and measure pH again. Repeat these opera- tions until a test solution of 6.5 to 7.2 pH at 25C is obtained. Just to ensure, confirm that the salt concentration of test solution is 50.5% using a salt concentration tester, etc. (9) After completion of preparing the test solution, cover the container to prevent entry of dust. 2. Control standard for test equipment The test equipment is required to be inspected to the following control standard to keep its normal condi- tion. *1) Standard values by former JIS K 8150-1989 (Sodium chloride Class 1) are shown as follows. Item Standard value Water solubility Within the limit pH value (5W/V%) 5.0 to 8.0 Sulphate (SO4) max. 0.005 % Heavy metal (as Pb) max. 0.001 % Potassium (K) max. 0.01 % Magnesium (Mg) max. 0.003 % Calcium (Ca) max. 0.003 % Barium (Ba) max. 0.001 % Iron (Fe) max. 0.0005 % Ingredient min. 99.0 % M0140 2004-N - 7 - Attachment Table 1 Inspection item Inspection method Standard or Tolerance Corrective action Inspection period 1. Air cleaners stain Remove the filter case by turning the ring thereof and inspect stain in the filter element. Must be free from stain Remove the filter element. Blow off air stains by using compressed air after soaking the filter element in gasoline or a thinner sufficiently. 2. The safety valve functioning of the air cleaner. Operate the air compres- sor. Check if the safety valve functions at 196.1 kPa 2 kgf/cm2. Functioning pressure: 196.1 kPa 2 kgf/cm2. Wipe off stains from the safety valve. Adjust the pressure regulating screw or replace with a new safety valve. Every 3 months 3. Air saturator: Water level and water Check the water level with the level gauge. The water level must be maintained between two level marks. Fill distilled water from inlet. Change the water completely at least every half a month. Every operation 4. Air saturator: elec- tric conductivity and insulation resis- tance of the heater Use a circuit tester or a megger. Check the electric conductivity between the terminals of the heater and the insulation resistance between the terminals of the heater and the air saturator. Continuity between the terminals should exist. Insulation resistance. 5 M cm min. Replace with a new heater. 5. Spraying pressure regulator function- ing Operate the air compres- sor and apply 176.5 kPa 1.8 kgf/cm2 pressurized air to the inlet of the air pressure gauge. Check if the air pressure is adjust- able between 0 to 176.5 kPa 0 to 1.8 kgf/cm2 by the gauge. Adjustable between 0 to 176.5 kPa 0 to 1.8 kgf/cm2. Overhaul or replace with a new one. 6. Air saturator func- tioning Operate the air compres- sor and check the indica- tions of the pressure gauge while regulating the pressure between 58.8 to 176.5 kPa 0.6 to 1.8 kgf/cm2. The indication of the pressure gauge must be within approximately 58.8 to 176.5 kPa 0.6 to 1.8 kgf/cm2. Check the clogging and leak- age of air piping, clean or repair. Every 3 months 7. Linings: Appear- ance Visually inspect the ap- pearance of the inside of the test chamber, water seal and cover. The linings must be free from cracks or holes. Repair the faulty part. Every 3 months 8. Spray nozzle: Ap- pearance Visually inspect the ap- pearance to check dam- ages or clogging. The nozzle must be free from damages or clog- ging. Replace damaged nozzle with a new one. Wash and clean off cloggings with hydrochloric acid solution or an undiluted sulfuric acid solution of potas- sium dichromate. (Abnormality of the air saturator is liable to cause the clogging of the spray nozzle) Every operation M0140 2004-N - 8 - Attachment Table 1 (Continued) Inspection item Inspection method Standard or Tolerance Corrective action Inspection period 9. Electric conductiv- ity and insulation resistance between the test chamber and the heater. Use a circuit tester or a megger. Check the electric conductivity between the terminals of the heater and the insulation resistance between the terminals of the heater and the test chamber sheathing. Continuity between the terminals should exist. Insulation resistance: 5 M cm and above. Replace with a new one or repair. Every 3 months 10. Thermometer (1) Visually check the con- tinuity of the mercury. (2) Compare with an ap- proved standard ther- mometer and calibrate by heating the thermometers in a temperature controlled chamber. The heating temperatures are 35C and 47C for the ther- mometers for the salt wa- ter chamber and the test chamber, and for the air saturator, respectively. The mercury must be continuous. Difference from former calibration must be within 1C. Mercury interruption: Replace the thermometer. Off-standard indication: Cali- brate or replace the ther- mometer. Every 6 months 11. Test chamber: Temperature con- trolled chamber functioning Set the temperature con- trolled chamber at 35C. Raise the temperature of the test chamber and c