DIN 51360-2-1981 Testing of cooling lubricants determination of corrosion preventing characteristics of cooling lubricants mixed with water chip filter paper method《冷却润滑剂的检验 掺水冷却的润.pdf

1、UDC 665.765-713 : 621 392 : 620.193 : 620.197 DEUTSCHE NORM Julv 1981 Testing of cooling lubricants Determination of corrosion preventing characteristics of cooling lubricants mixed with water Chidfilter DaDer method - DIN 51 360 - Part 2 Prfung von Khlschmierstoffen; Bestimmung der Korrosionsschutz

2、eigenschaften von wassergemischten Khlschmierstoffen; Spne/Filtrierpapier-Verfahren Supersedes June 1977 edition In keeping with current practice in standards published by the International Organization for Standardization (ISO), a comma has been used throughout as the decimal marker. See Explanator

3、y notes for connection with IP 287/78 published by the Institute of Petroleum (IP). 1 Field of application Cooling lubricant mixed with water) (cooling lubricant miscible with water in the “ready for use“ condition). 2 Scope The method specified in thisstandard serves to determine the corrosion prev

4、enting characteristics of cooling lubri- cants mixed with water, using grey cast iron chips placed on filter paper. 3 Standards to be observed DIN 1691 DIN 4188 Part 1 DIN 12 339 DIN 12448 DIN 50014 DIN 50 900 Part 1 DIN 51 750 Part 1 DIN 51 750 Part 2 DIN 51 848 Part 1 Cast iron with lamellar graph

5、ite (grey cast iron) Sieving media; woven wire cloth sieving media for analytical sieves; dimensions Laboratory glassware; Petri dishes Laboratory equipment; paper fibre materials; paper filters Atmospheres and their technical application; standard atmospheres Corrosion of metals; terminology, gener

6、ic terms Testing of petroleum; sampling, general Testing of petroleum; sampling, liquid substances Testing of petroleum; precision of test methods, general, terminology used in standards specifying requirements 4 Concept As defined in DIN 50900 Part 1,corrosion is the reaction of a metallic material

7、 with its surroundings, which gives rise to a measurable alteration of the material and which can lead to corrosion damage. The yardstick of corrosion in the test as described in the present standard is provided by the degree of staining observed on a circular filter paper, which arise as the result

8、 of the action of cooling lubricant mixed with water on grey cast iron chips lying on the filter paper. 5 Principle of method A mixture of the sample with water of the kind described in clause 8 is produced by stirring in a beaker. Chips are placed on a circular filter paper and wetted with the fres

9、hly prepared mixture, then exposed to room temper- ature for two hours in a Petri dish, and immediately thereafter the circular filter paper is assessed visually in respect of the degree of staining. 6 Designation of test method Designation of the method of determining the corrosion preventing chara

10、cteristics of cooling lubricants mixed with water using the chip/filter paper method (A), in accordance with this standard (02): Test DIN 51 360 - 02 - A 7 Apparatus 2 litre beaker, tall form, e.g. DIN 12 331 -HF 2000 beaker. 50 ml glasssyringe fitted with metal tip and metal piston. Stirrer, with a

11、 rotational speed of 750 min-l. fitted with a stirring paddle of stainless steel 120 mm long, 19 mm wide and 1.5 mm thick. DIN 12448-A70-2bcircularfilter markedwith a 40 mm diameter circle. Spoon spatula of corrosion-resistant material. DIN4188-2and DIN4188-4wovenwirecloth sieving media of stainless

12、 steel. DIN 12 339 - AB2 - 80 X 20 Petri dish. 2 ml one-mark bulb pipette, e.g. DIN 12 690- VPA2 pipette. 1 See DIN 51 385 for definitions relating to cooling lubricants. Continued on pages 2 to 4 Beuth Verlag GmbH. Berlin 30. has exclusive sale rights for German Standards (QIN Normen) DIN 51 360 Pa

13、rt 2 Engl. Price group 5 06. 85 Sales No. 0105 Page2 DIN 51 360 Part 2 8 Reagents Dry-turned grey cast iron chips prepared from GG-25 material complying with DIN 1691, chip size 3 to 6 mm *). The chips shall be stored dry in a desiccator with a desiccant, e.g. phosphorus pentoxide. Water with a tota

14、l hardness of the following molar concentration 3) : c (CaC12. 6 H20, MgSO,. 7 H20) = 3.58 mmol/l shall be used. The water shall be made from: 17 ml of solution A, 3 ml of solution B and 980 ml of boiled off and cooled down distilled chemically pure water. Water purified over ion exchangers shall on

15、ly be used if the evaporation residue is less than 2 mg/l. Solution A: 39 g of reagent grade calcium chloride hexahydrate (CaC12 . 6H20) shall be dissolved in distilled water to 1 litre. 1 ml of solution A diluted with distilled water to 1 litre results in a water of molar concentration c(CaC12 .6H2

16、0j =0,179 mmol/l. Solution 6: 449 of reagent grade magnesium sulfate heptahydrate (MgS04 . 7H2O) shall be dissolved in distilled water to 1 litre. 1 ml of solution B diluted with distilled water to 1 litre results in a water of molar concentration c (MgS04 .7 H20j = 0.1 79 mmol/l. Chemically pure ac

17、etone. 9 Sampling In accordance with DIN 51 750 Part 1 and Part 2. 10 Preparation 10.1 Sample solution For the test, the cooling lubricant shall be mixed with water, unless it is supplied in the form of a product already mixed with water. A water of specifically defined total hardness, prepared as d

18、escribed in clause 8, shall be used for the mixtures. If the test is carried out with a different water, this shall be noted in the test report. Water freshly prepared in accordance with clause 8 shall be transferred to the 2 I beaker and the appropriate quantity of cooling lubricant to be tested in

19、jected into the beaker by means of the glass syringe, stirring con- stantly. The total quantity injected shall be 1 litre. The stirrer paddle shall be situated approx. 20 mm above the bottom of the beaker during this process. After comple- tion of the injection of lubricant, stirring shall continue

20、for another five minutes. 10.2 Grey cast iron chips (test chips) The chips shall be examined visually in respect of freedom from corrosion. They shall not be touched with the naked hand. (30 f 5) chips shall have a mass of 2 g. If the number of chips is greater or smaller, a subsequent sieving with

21、the aid of the test sieves shall be carried out. The chips used as test chips shall be the chips which pass through the test sieve being fitted with a DIN 4188-4 stainless steel woven wire cloth (4 mm aperture size) and which are thereafter retained on the test sieve fitted with a DIN 41 88 - 2 stai

22、nless steel woven wire cloth (2 mm aperture size). 11 Procedure Two tests shall be carried out with each mixture (see subclause 10.1). The mixture shall be freshly prepared before the test. With the aid of the spoon spatula, (2 f 0.1) g of chips (see subclause 10.2) shall be spread uniformly on the

23、marked area of the circular filter paper placed in the Petri dish. The chips shall be wetted uniformly with 2 ml of the sample solution prepared in accordance with sub- clause 10.1, using the 2 ml one-mark bulb pipette. Then the lid shall be placed on the Petri dish. The Petri dishes prepared in thi

24、s fashion shall then be exposed for two hours, but not for any longer than two hours and ten minutes, to a temperature situated between 18 and 28 OC. They shall be arranged in such a way that they are protected from draughts and from direct sunlight. Thereafter the chips shall be removed, the circul

25、ar filter paper shall be rinsed under running potable water (moderate jet), then swung back and forth in acetone for about five seconds and finally dried at a room temperature of between 18 and 28 OC specified in DIN 50 014. 12 Evaluation Immediately after the circular filter paper has been cleaned

26、and dried, the degree of staining (see table) on the circular filter paper shall be ascertained by visual examination without any optical aids or auxiliary means. The table below may be of assistance in assessing the degree of staining. If the assessments for the two filter papers differ from each o

27、ther by more than one degree of staining, the test shall be repeated. Note. The surface area of a filter paper to be evaluated amounts to 1256 mm2. In order to determine the number of stains on the filter paper more accurately, it is recommended to use a transparent paper with a mm grid. 13 Expressi

28、on of result The degree(s) of staining of the areas of the two filter papers to be assessed shall be expressed as the results of the test, with reference to the present standard. Example: When testing a cooling lubricant, the surface of the first circular filter paper was assessed as having a degree

29、 of 2j Information on suppliers can be obtained from: DIN-Bezugsquellen fr normgerechte Erzeugnisse im DIN Deutsches Institut fr Normung e. KI Burggrafenstrasse 4- 10, D-1000 Berlin 30. 3, See DIN 32 625. staining O, and the surface of the second circular filter paper was assessed as having a degree

30、 of staining I. The result shall then be given as: Degree of staining O and 1 in accordance with DIN 51 360 Part 2. Degree of staining O O O 1 3 O 0 Figure. Examples of evaluation for degrees of staining O to 4 The following additional information shall be provided together with the test result: for

31、m on delivery and designation of the tested cooling lubricant miscible with water; mixture ratio of cooling lubricant with water, expressed as a percentage by volume of cooling lubricant; DIN 51 360 Part 2 Page 3 Degrees of the filter paper - Degrei of ;tainin( O _. 1 2 3 4 - Meaning No staining Tra

32、ces of staining Slight staining Moderate staining Heavy staini ng Description (surface of filter paper) No stains visible Three stains at the very most, of which none has a diameter exceeding 1 mm Not more than 1 % of the surface discoloured, but more or larger stains than for degree of staining 1 I

33、 More than 1 %,but not more than 5 % of the surface discoloured More than 5% of the surface I d iscoloured if applicable, any deviations from this standard; date of test. 14 Precision (in accordance with DIN 51 848 Part 1) The following criteria shall be used for assessing the reliability of results

34、: Repeatability (one operator, one apparatus) If two results are obtained by the same operator under repeatability conditions, both results shall be considered acceptable and in accordance with the specifications of the standard if the four values of the two pairs of measured values do not differ fr

35、om one another by more than one degree of staining, whichever pairing is adopted. Reproducibility (different operators, different apparatus) If two single and independent results are obtained in two different laboratories under comparable conditions, they shall be considered acceptable and in accord

36、ance with the specifications of the standard if the four values of the two pairs of measured values do not differ from one another by more than two degrees of staining, whichever pairing is adopted, with the following exceptions: if one of the two pairs of measured values to be com- pared happens to

37、 be “O and O“ or “4 and 4“, then the permissible deviation shall be limited to one degree of staining. Page 4 DIN 51 360 Part 2 Previous editions 08.75, 06.77. Amendments The following amendments have been made in comparison with the June 1977 edition: see “Explanatory notes“ Explanatory notes The p

38、resent standard, prepared by Working Group 661.1 Prfung von Khlschmierstoffen of the Fachausschuss Minerall- und Brennsto ffnormung (FAM) of the Normenausschuss Materialprfung (NMP), ( Mater ia Is Testing Standards Committee), supersedes the edition of the standard bearing the same DIN number and da

39、ted June 1977, without any previous publication of a draft standard. Apart from the editorial revision of the text, the fol- lowing amendments have been made in comparison with the previous edition of the standard. Two new clauses have been added, viz. “Standards to be observed“ and “Designation of

40、test method“, the latter clause having been incorporated in this standard mainly for use in data processing. Code letter A relates to the test method as specified in the present standard. If, during the course of a future revision of the standard, any fundamental specifications are altered, it will

41、be necessary to adopt a new code letter. As regards the grey cast iron chips (test chips), the GG -25 material in accordance with DIN 1691 has been specified in lieu of the GG -30 material. The size of the chips has also been changed from min 6 rnm X 6 mm to between 3 mm and 6 mm. The chips of this

42、size represent the fraction between the wire cloth sieving medium DIN 4188-4 nr. St and the wire cloth sieving medium DIN 4188 - 2 nr. St. The check is made by weighing. (30 i: 5) chips of this size have a mass of 2 g. These specifications also represent a new feature in the standard. There is a nee

43、d for a standardized rapid test method for cooling lubricants miscible with water (see DIN 51 385, October 1976 edition for terminology) which covers the corrosion preventing characteristics of cooling lubricants mixed with water. Such a standardized test method is designed to supersede the many and

44、 varied methods adopted by individual users for the testing of the corro- sion preventing characteristics of these lubricants. On the basis of an inter-laboratory test organized by the Fachausschuss Minerall- und Brennsto ffnormung (FAM), a good degree of consistency was achieved, and the test preci

45、sion specified was deduced therefrom. The method of preparation of the cooling lubricant mixed with water which is described in the present standard corresponds to the method described in DIN 51 367 concerning the testing of the stability of emulsive cooling lubricants when mixed with hard water. Th

46、e IP 287/78 Tentative document “Rust prevention characteristics of soluble oil emulsions, chip/filter paper method“ published by the Institute of Petroleum (IP) is technically equivalent to DIN 51 360 Part 2, but it differs in the following points: a) The area of filter paper covered with chips is a

47、 square, and it is 31 mm2 smaller than the area specified in DIN 51 360 Part 2. b) The material is different, and the quantity required for a test is not specified. c) The hardness of the water used is lower. The water is less corrosive. d) The total quantity of the prepared sample amounts to one te

48、nth of that specified in the present standard, and its preparation is not described. e) A duplicate test is not carried out. f) The evaluation is not effected according to degrees of staining, but a certain point (the breakpoint) is determined in lieu thereof, at which the stained area of the filter paper increases considerably, as a function of the dilution used.