1、BRITISH STANDARD BS5117-2.1: 1985 Testing corrosion inhibiting, engine coolant concentrate (“antifreeze”) Part2: Methods of test for corrosion inhibition performance Section2.1 General procedures NOTEIt is recommended that this Section be read in conjunction with the information given in the “Genera
2、l Introduction” published separately as BS5117-0. UDC 661.17:621.43715.4:620.197.3BS5117-2.1:1985 This British Standard, having been prepared under the directionof the Chemicals Standards Committee, was published under the authority ofthe Board of BSI and comes intoeffect on 28June1985 BSI09-1999 Fi
3、rst published as BS5117 December1974 First part revision Section2.1 June1985 The Committees responsible forthis British Standard are showninPart0 The following BSI references relate to the work on this standard: Committee reference CIC/7 Draft for comment83/55151 DC ISBN 0 580 14356 2 Amendments iss
4、ued since publication Amd. No. Date of issue CommentsBS5117-2.1:1985 BSI 09-1999 i Contents Page 1 Scope 1 2 Sampling of the product 1 3 Preparation and assembly of metal test specimens 1 4 Additional cleaning procedures for metal test specimens carrying adherent corrosion products 3 5 Special proce
5、dure for cleaning heavily corroded metal test specimens and determination of mass loss 4 6 Preparation of standard water used for test solutions in the glassware, recirculating rig and static engine tests 5 7 Determination of volume of suspended solids 5 Figure 1 Diagram of the glassware test appara
6、tus 2 Figure 2 Recirculating rig test: specimen assembly 3 Figure 3 Graph showing mass loss during repeated cleaning cycles 6 Table 1 Graduation of centrifuge tube 5 Publications referred to Inside back coverBS5117-2.1:1985 ii BSI 09-1999 A British Standard does not purport to include all the necess
7、ary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to
8、6, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS5117-2.1:1985 BSI 09-1999 1 1 Scope This Section of BS5117 specifies general procedures wh
9、ich are common to the corrosion inhibition tests described in BS5117-2. NOTE 1The engine coolant concentrate is referred to hereafter as“the product”. NOTE 2The titles of the publications referred to in this standard are listed on the inside back cover. 2 Sampling of the product Take a representativ
10、e sample of not less than500mL, preferably from previously unopened containers in which the product is normally offered for sale 1)Place the sample in clean, dry, stoppered glass bottles of a dark colour. Agitate all containers before sampling to ensure homogeneity of the contents. Where a batch of
11、containers is to be sampled, it is essential that the number of containers sampled is not less than the cube root of the number of containers in the batch. Prepare the final sample by taking equal portions from each container sampled and mix them together thoroughly. Take care to ensure that any met
12、hod used for sealing the sample does not cause contamination. NOTEA series of different tests may be carried out by using separate portions taken from one sample. 3 Preparation and assembly of metal test specimens 3.1 Specimens Each of the metal test specimens shall be50mm 25mm, with a central6mm ho
13、le. The specimens taken from cast materials shall be3mm thick, and the remainder1.5mm thick. The metals 2)to be used are: a) Steel, complying with class CR4 or CS4, general purpose finish, of BS1449-1. b) Copper, complying with grade Cu-ETP-2 of BS6017, cut from annealed copper strip complying with
14、the requirements of BS1432. c) Brass, complying with type CZ106 of BS2870, cut from half-hard sheet. d) Solder 3) , containing tin2.4% to2.6%; silver0.45% to0.55%; antimony0.40%max.; arsenic0.05%max.; bismuth0.15%max.; copper0.05%max.; nickel0.01%max.; iron0.01%max.; zinc nil; aluminium nil; others0
15、.10%max; lead remainder. Either cut or cast solid specimens are suitable. e) Aluminium alloy, complying with type LM4 of BS1490. f) Cast iron, complying with grade260 of BS1452, cut from suitable30mm diameter cast bar. NOTEIt is advisable that each metal test specimen be carefully stamped with an id
16、entification mark to prevent confusion between similar specimens. 3.2 Preparation of specimens Rub all specimens except those of solder, on wet sheets of grade P280 silicon carbide waterproof paper complying with BS871, to give a uniform surface finish. Use separate sheets for each material. Brush a
17、ll specimens vigorously, using a moist bristle brush. Rinse the specimens thoroughly with running tap water, rinse with acetone, dry and weigh to the nearest1mg. Store the specimens in a desiccator for a minimum of48h before use. At all times handle the washed specimens only with forceps or clean, g
18、rease-free cotton gloves. 3.3 Assembly of specimens Assemble the specimens on a non-conducting rod of diameter small enough to slip easily through the central hole in the specimens. Separate the specimens from each other by cylindrical spacers,5mm long,11mm outside diameter and6mm inside diameter. A
19、t each end of the assembly place a brass“leg”,50mm by25mm, cut from1.5mm brass sheet, and with a hole6mm in diameter, off-centre towards one end of the brass piece so that the “legs” are orientated with their long axes in the same directions as the long axes of the specimens (see Figure 1). NOTEFor
20、the recirculating rig test, brass legs are not used (seeFigure 2). Assemble the specimens and “legs” in the following order: brass “leg”, copper, solder, brass, steel, cast iron, aluminium alloy, brass “leg”. Use spacers of polytetrafluoroethylene (PTFE), for electrical insulation, between the brass
21、 “legs” and the adjacent specimens and between the brass and steel specimens; use brass spacers between the brass, solder and copper specimens; use steel spacers between the steel, aluminium alloy and iron specimens. 1) See A.2 of BS5117-0:1985 and clauses4 and5 of BS3195-1:1978 for further guidance
22、 on sampling procedures and equipment. 2) For information on the availability of suitable test metals, apply to Enquiry Section (London), British Standards Institution, enclosing a stamped addressed envelope for reply. 3) Solder complying with Ford Motors specification M11A10A has been found suitabl
23、e.BS5117-2.1:1985 2 BSI 09-1999 Figure 1 Diagram of the glassware test apparatusBS5117-2.1:1985 BSI 09-1999 3 Provide an arrangement to tighten the assembly of “legs”, spacers and specimens together so as to ensure that the three specimens in each section of the assembly are held firmly in good elec
24、trical contact with each other. 4) 4 Additional cleaning procedures for metal test specimens carrying adherent corrosion products WARNING. The cleaning solutions described in this clause, and their constituents, are toxic and/or corrosive. Avoid breathing associated dust or fumes, and prevent contac
25、t with the eyes and skin, during preparation and use. Take appropriate precautions in disposal of waste solutions. 4.1 Reagents The reagents used shall be of recognized analytical grade. Unless otherwise stated, water complying with BS3978 shall be used throughout. Figure 2 Recirculating rig test: s
26、pecimen assembly 4) One such arrangement comprises the use of a lock nut and spring washer on the outside of the legs.BS5117-2.1:1985 4 BSI 09-1999 4.2 Chemical treatment 5) 4.2.1 Iron and steel 4.2.1.1 General. Clean the specimen either electrolytically or by using “Clarkes solution” as described i
27、n4.2.1.2 and4.2.1.3 respectively. 4.2.1.2 Electrolytic cleaning. The specimen is made the cathode in an electrolytic cell using a suitable inert anode, for example lead or graphite. The electrolyte may be an inhibited sulphuric acid solution, prepared as described below, or a50g/L solution of triamm
28、onium citrate. Prepare the inhibited sulphuric acid solution by carefully adding, with stirring,55mL of sulphuric acid, approximately98%(m/m) solution, to945mL of water contained in a suitable beaker. Then add an appropriate quantity of a suitable organic inhibitor, for example2g of1,3-di-o-tolyl-2-
29、thiourea, and stir to dissolve or disperse the inhibitor. Current is passed through at about 4 Aper specimen for5min at a solution temperature of70 C. 4.2.1.3 Cleaning using “Clarkes solution” (hydrochloric acid approximately36%(m/m) solution, containing5% of tin(II) chloride and2% of diantimony tri
30、oxide). The specimen is kept agitated during immersion in the derusting solution, for periods of about20s to30s, rinsing thoroughly with running tap water after each immersion, until complete derusting has been obtained. 4.2.2 Copper and brass. Immerse the specimen for15s in cold hydrochloric acid s
31、olution prepared as follows. Carefully dilute430mL of hydrochloric acid, approximately36%(m/m) solution, to1000mL with water. 4.2.3 Aluminium alloy. Immerse the specimen for5min in a boiling solution prepared as follows. Carefully dilute20mL of orthophosphoric acid, approximately88%(m/m) solution, t
32、o1000mL with water and add either20g of chromium(VI) oxide or30g of potassium dichromate, stirring to dissolve the reagent. 4.2.4 Solder. Immerse the specimen for5min in boiling acetic acid solution prepared as follows. Carefully dilute12mL of glacial acetic acid to1000mL with water. 4.3 Washing Aft
33、er each cleaning treatment described above, wash the specimen in running water, brush with a moist bristle brush, dry and weigh. 4.4 Blank value When a suitable set of conditions has been established for cleaning a specimen, determine the average mass loss resulting from cleaning three uncorroded sp
34、ecimens and deduct this blank value from all mass losses obtained on similar specimens cleaned in this way. 5 Special procedure for cleaning heavily corroded metal test specimens and determination of mass loss 5.1 Introduction Using the procedures described in clause4 to determine the mass losses in
35、 a corrosion test may not be reliable for cases where heavily corroded specimens are to be cleaned. A corroded surface, particularly of a multiphase alloy, is often more susceptible than a new, machined or polished, surface to corrosion by the cleaning procedure; thus the blank value determined in a
36、ccordance with4.4 may not be valid. In such cases the procedure described in5.2, 5.3 and5.4 should be followed. 5.2 Cleaning The cleaning cycle is as described in clause4 and comprises chemical treatment, washing, drying and weighing. For each specimen, repeat the cleaning cycle, in identical fashio
37、n, several times and determine the mass loss after each cycle to the fifth significant figure. NOTERepetition of the cleaning treatment may be necessary initially in order to remove completely the corrosion products. This removal can often be confirmed by examination with a low power( 7 to 30 magnif
38、ication) microscope. This is particularly useful with pitted surfaces when corrosion products may accumulate in pits. 5.3 Determination of mass loss corresponding to removal of corrosion products Plot the total mass loss after each cleaning cycle as a function of the number of cleaning cycles (seeFi
39、gure 3). Two lines will be obtained, AB and BC, the latter of which corresponds to corrosion of the metal by the cleaning treatment after removal of the corrosion products. The true mass loss in the corrosion test, corresponding to removal of the corrosion products, is obtained by extrapolating the
40、line BC to the mass loss axis, at point D. NOTEIf the cleaning treatment does not corrode the metal, the line BC will be horizontal and point B will represent the true mass loss. 5) For the purposes of this British Standard, chemical treatment includes electrolytic treatment and chemical immersion t
41、reatment.BS5117-2.1:1985 BSI 09-1999 5 5.4 Choice of cleaning method To minimize the problem of corrosion of the metal by the cleaning treatment, the cleaning method should be chosen so that the slope of the line BC is as low (near to horizontal) as possible. 6 Preparation of standard water used for
42、 test solutions in the glassware, recirculating rig and static engine tests 6.1 Reagents The reagents used shall be of recognized analytical grade. Water complying with BS3978 shall be used throughout. 6.2 Solution preparation Weigh, to the nearest0.001g,0.444g of anhydrous sodium sulphate,0.495g of
43、 dry sodium chloride and0.414g of dry sodium hydrogen carbonate. Dissolve the salts in water and dilute to3000mL. 7 Determination of volume of suspended solids 7.1 Introduction This clause describes a method for the determination of the volume content of suspended solids in solutions of the product,
44、 particularly those obtained from engine cooling systems during field trials. 7.2 Principle A100mL test portion is centrifuged at a specified relative centrifugal force until the volume of sediment is constant. 7.3 Apparatus 7.3.1 Centrifuge, capable of centrifuging two or more filled tubes at a spe
45、ed which can be controlled to give a relative centrifugal force of between500and800at the tips of the tubes. NOTEThe required speed of rotation may be calculated using the following equation: N = 1 336f/d For example, if D =300mm then a speed of1725r/min is required for f to be500and a speed of2182r
46、/min is required forf to be800. 7.3.2 Centrifuge tube, with a conical bottom, made of annealed glass, and graduated as given in Table 1, calibration being made with air-free water at20 C, reading the bottom of a shaded meniscus. Table 1 Graduation of centrifuge tube 7.4 Procedure Fill the centrifuge
47、 tube to the100mL mark with the solution of the product, well shaken to ensure that the solid content is evenly distributed. Place the tube in a trunnion cup opposite another filled tube to establish a balanced condition and centrifuge for10min at a rate sufficient to produce a relative centrifugal
48、force between500 and800 times the standard value of gravity 6)at the tips of the whirling tubes. Read and record the volume of sediment to the nearest scale division. Repeat this operation until the volume of sediment remains constant. Report the volume of sediment as a percentage of the volume of t
49、he test portion. where N is the speed of rotation (in r/min); f is the centrifugal force relative to the standard value of gravity; D is the diameter of .swing measured during the tips of opposite tubes when in the rotating position (in mm); Range Subdivision Volume tolerance mL 0 to0.1 above0.1 to0.3 above0.3 to0.5 above0.5 to1.0 above1.0 to2.0 above2.0 to100 mL 0.05 0.05 0.05 0.10 0.10 mL 0.02 0.03 0.05 0.05 0.10 0.10 6) The standard value of gravity is9.80665m/s 2 .BS5117-2.1:1985 6 BSI 09-1999 Figure 3 Graph showing mass loss dur
