1、CEN EN*2B050 92 3L)OY589 0028925 9 W - EUROPEAN STANDARD EN 28050 NORME EUROPENNE EUROPISCHE NORM May 1992 UDC 699.16 24-198-4 : 620.11 Descriptors: Ferroalloys, ferronickel, ingots, sampling, samples English version Ferronickel ingots or pieces - Sampling for analysis (IS0 8050 : 1988) Ferro-nickel
2、 en lingots ou en morceaux - chantillonnage pour analyse (IS0 8060 : 1988) Ferronickelbarren oder -stcke - Probenahme fr Analyse (IS0 8050 : 1988) This European Standard was approved by CEN on 1992-5-08. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the con
3、ditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in thre
4、e official versions (English, French, German). A veision in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Aus
5、tria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: r
6、ue de Stassart 36, B-1050 Brussels O CEN 1992 Copyright reserved to all CEN members Ref. No. EN 28050 : 1992 E Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-CEN EN*28050 92 340
7、4589 002892b O Page 2 EN 28050 : 1992 Foreword On the proposal of the CEN Central Secretariat, the Tchnical Board has decided by Resolution BT C157/1990 to submit the International Standard IS0 8060 : 1988 Ferronickel ingots or pieces - Sampling for analysis to the formal vote. This European Standar
8、d EN 28050 was approved by CEN on 1992-05-08. National standards identical to this European Standard shall be published at the latest by 1992-11-30 and conflicting national standards shall be withdrawn at the latest by 1992-11-30. According to the CENKENELEC Internal Regulations, the following count
9、ries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of the International Standard IS0 8050 :
10、 1988 was approved by CEN as a European Standard without any modification. Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3404589 0028927 2 Page 3 EN 28050 : 1992 Ferronickel in
11、gots or pieces - Sampling for analysis 1 Scope This International Standard specifies a method for sampling of ferronickel lots in ingot or piece form with a view to obtaining a representative laboratory sample for the determination of the chemical .composition of the lot. As agreed between the purch
12、aser and the supplier, a choice is to be made between two procedures: - plant during casting (description in clauses 3 and 5). The first procedure can be applied at the producers - The second procedure can be applied to lots as delivered at the buyers premises) (description in clauses 4 and 5). It i
13、ncludes two alternatives for sample taking (drill- ing and milling). Each party is entitled to participate in (or be represented at) sampling operations. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this Internation
14、al Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encour- aged to investigate the possibility of applying the most recent editions of the standards listed below. Member
15、s of IEC and IS0 maintain registers of currently valid International Standards. IS0 513 : 1975, Application of carbides for machining by chip removal - Designation of the main groups of chip removal and groups of application. IS0 3855 : 1977, Milling cutters - Nomenclature. IS0 4957 : 1980, Tool ste
16、els. IS0 6352 : 1985, Ferronickel - Determination of nickelcontent - Dimeth ylglyoxime gravimetric method. IS0 6501 : 1988, Ferronickel - Specifications and conditions of delivery. 3 Sampling of each heat at the producers plant 3.1 Taking the primary sample during casting 3.1.1 Each increment2) shal
17、l be taken using a spoon and cast in a mould to obtain a suitable small ingot for chemical or physical analysis. The usual geometry of such ingots is that of a frustum. It is desirable that the dimensions lie within the follow- ing limits: - height: 100 to 140 mm - upper diameter: 35 to 50 mm - lowe
18、r diameter: 30 to 40 mm The ingot mould shall be made of material that allows the sample to cool rapidly; a large block of copper would meet this requirement. If necessary, the sample shall be killed to obtain a small ingot of sound metal (free of cracks and blowholes). Killing is most often done wi
19、th aluminium, in wire or chip form, at 1 to 2 g of aluminium per kilogram. The large height of the small ingots permits small shrinkholes to be confined to the upper part, thus ensuring that the lower part of the ingot is perfectly sound and homogenous and hence suitable for analysis. Generally, a h
20、eight of 120 mm will guarantee that the sound portion extends at least 70 mm up from the base. 3.1.2 In general, the small ingots are used for physical analysis on solid metal after a disc is cut from them. Whenever possible, this analysis should produce results as ac- curate as those obtained from
21、chemical analysis of chips. To achieve such accuracy, it is often necessary to analyse several small ingots several times each. A specified number of small ingots shall therefore be taken at regularly spaced intervals during the casting. Examples are given in annex A to indicate the number of small
22、ingots to be taken and the number to be analysed. It is sug- gested that four to eight small ingots be taken from each heat. 1) This procedure can be applied at the producers plant, at the buyers premises or at an intermediate transit place, as agreed between the in- terested parties. 2) Increment:
23、portion of the lot taken in a single operation; in this standard : portion of molten metal. Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-CEN EN*28050 92 Page 4 EN 28050 : 1992
24、 It may happen that for some exceptional reasons there are not enough small ingots available which are suitable either for ac- curate physical analysis or for accurate analysis of chips taken from them: some small ingots may no longer be available or may contain cracks or blowholes. In these circums
25、tances, the ingots constituting the heat shall be sampled. Five ingots) shall be taken from the heat, and the procedure described beginning at clause 4.1.3” 2, shall then be followed. 3.2 Secondary sampling of small ingots taken from the heat 3.2.1 Cutting Each small ingot shall be cut in two about
26、10 or 15 mm from the bottom (the srnaller-diameter end) with a cut-off wheel (made of carborundum or corundum, for example). The use of water cooling is recommended, because it avoids heating of the sample and hence changes in the crystalline structure of the metal. 3.2.2 Use of the two pieces of th
27、e small ingot 3.2.2.1 The disc cut off the small ingot may be used for physical analysis (.e. X-ray fluorescence or optical emission spectrometry) of the solid metal after adequate machining of the cut surface. For the number of small ingots to be analysed and the number of determinations per small
28、ingot, see annex A. 3.2.2.2 The larger piece may be used for preparing chips, using one of the two following methods: a) Drilling With the freshly cut surface facing upwards, the piece shall be drilled to a depth such that the pipe in the upper part of the small ingot (.e. at the wider end) is not r
29、eached. It is desirable to limit the depth of the drilled hole to 50 mm. By using a 20 mm diameter drill, more than 100 g of chips are obtained. 1) The rules for random sampling given in annex B may be used. 3404589 O028928 4 All the chips shall be collected. An assembly similar to that of figure 1
30、may be used for this purpose. It is particularly suitable when using a drill bit designed for oil cooling but fed with compressed air (see annex D, D.6.3). The assembly shall be made of materials which will not con- taminate the chips. The recommended conditions for drill- ing are described in annex
31、 D. b) Milling The conical surface adjacent to the freshly cut surface shall be cleaned by grinding with a corundum (aluminium oxide) or carborundum grinding wheel and then milled to a depth of about 20 mm from the cut surface (this will provide 100 g of chips). All the chips shall be collected. The
32、 recommended conditions for milling are described in annex D. All the chips obtained from the selected small ingots by one of the two techniques described above shall be combined to constitute the secondary sample which is treated according to the procedure in clause 5 to obtain the final laboratory
33、 sample, 4 Sampling of a lot of ingots or pieces 4.1 Sampling of ingots or pieces 4.1.1 Lots comprising one heat The procedure as described in the last paragraph of 3.1 is used (5 ingots or pieces are taken in accordance with the rules for random sampling). 4.1.2 Lots comprising several heats The mi
34、nimum number N of ingots or pieces to be taken is given by the following rules3): For lot tonnages between 5 and 80 t N=!3 For lot tonnages between 80 and 500 t N = 54 - - (see footnote 4) T 20 where Tis the mass, in metric tons, of the lot. 2) A very small number of ingots constitutes a sufficientl
35、y representative sample of the heat, because the contents of different ingots from the same heat do not vary greatly (see annex Cl. 3) These rules have been established making the following practical assumptions: - the lots are composed of heats each of mass about 20 t; - the nickel contents of the
36、heats in the lot lie within the range from k to (k + 1) %, where k is an integer; - variations in nickel content within ingots and between ingots from the same heat are negligible compared with the range k to (k + 1) %. Complete justification of these rules is given in annex C. 4) This rule applies
37、only when the tonnage does not exceed 500 t. If, following an agreement between the purchaser and the supplier, a consign- ment is between 500 and 1 O00 t, the interested parties may agree to use one of the following procedures: - division of the consignment into lots of tonnages not exceeding 500 t
38、; - taking, from the whole consignment, only the number of ingots or pieces specified for a tonnage of 500 t, .e. N = 29. This procedure con- siderably diminishes the quantity of work involved in taking secondary samples from ingots or pieces, Copyright European Committee for Standardization Provide
39、d by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-CEN EN*28050 92 = 3404589 O028929 b W Tonnage T of ferronickel t 5 to 80 100 140 200 240 300 340 400 440 500 500to1000 These rules are illustrated in table Number N of ingots or pieces t
40、o be taken 50 49 47 44 42 39 37 34 32 29 29 The number of ingots or pieces may be increased by agreement between supplier and purchaser. The rules for random sampling shall be respected. In order that such is the case for different methods of delivery, the pro- cedure given in annex B is recommended
41、. 4.1.3 The surface of each ingot or piece taken shall be care- fully cleaned by washing, brushing or wiping as required in order to eliminate all foreign material (earth, dust, oil, etc.). The selected ingots or pieces constitute the primary sample. 4.2 Taking chips from ingots or pieces This proce
42、dure consists of producing turnings by either drilling or milling. These operations shall be performed in such a way that the chips are not contaminated by tool wear, dust or grease. In particular, the work shall be done dry. For a detailed description of the conditions for machining, see annex D. C
43、ertain types of ferronickel are extremely hard. Great care shall therefore be taken to ensure that suitable cutting tools and con- ditions are selected. For hard types of ferronickel, heat treatment (tempering) of the solid metal (ingot, ingot part or piece) may be desirable, because it makes it muc
44、h easier to take chips. (For details, see annex D, clause D.2.) 4.2.1 Drilling Each ingot shall be drilled to half-thickness at one point using either a drill made of high-speed steel or a tungsten carbide drill, Drilling shall be done from the upper surface of one ingot and the lower surface of the
45、 next. Page 5 EN 28050 : 1992 A drill between 12 and 20 mm in diameter is recommended; drills in the 15 to 17 mm range are most frequently used. NOTE - Examples of suitable drills, and the conditions under which they should be used, are given in annex D. Chips shall be discarded until the drill has
46、worked its way into the material to its full diameter. All the remaining chips shall then be collected. An assembly similar to that shown in figure 1 may be used for colection. It shall be made of materials that will not con- taminate the chips. For pieces, the drill shall penetrate to mid-thickness
47、 of the piece. 4.2.2 Milling The ingots shall be cut with corundum (aluminium oxide) or carborundum wheels. Either each ingot shall be cut once, and one of the two resulting pieces then milled, or a slice of thickness sufficient for milling shall be cut from the ingot. The outside surface adjacent t
48、o the freshly cut surface to be milled shall be cleaned. This can be done with a corundum or carborundum grinding wheel. The surface shall then be milled with a suitable milling cutter, and all the chips collected. Pieces shall be cut and milled in the same way as ingots. NOTE - Examples of suitable
49、 milling cutters, and the conditions under which they should be used, are given in annex D. The chips obtained either by drilling or milling shall have a mass of a least 1 kg. These chips constitute the secondary sample which shall be treated as described in clause 5. 5 Treatment of chips The secondary sample is constituted of chips obtained as described in 3.2.2.2 or 4.2. 5.1 Washing It is strongly recommended that the complete secondary sample be washed twice with pur
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