1、DEUTSCHE NORM June 2002Stainless steel wire wrapped well screensPart 1: Sizes DN 40 to DN 100 threaded screens with continuous slotContinued on pages 2 to 6.Wickeldrahtlterrohre aus nichtrostendem Stahl fr Brunnen Teil 1: DN 40 bis DN 100 mit kontinuier-licher Spaltweite und GewindeverbindungIn keep
2、ing with current practice in standards published by the International Organization for Standardization (ISO), a comma has been used throughout as the decimal marker.All dimensions are in millimetres.ForewordThis standard has been prepared by Technical Committee Brunnenbau of the Normenausschuss Wass
3、er-wesen (Water Practice Standards Committee).1 ScopeThis standard species dimensions and requirements for DN 40 to DN 100 threaded stainless steel wire wrapped well screens with continuous slot, designed for use with stainless steel, plastics-coated steel or unplasticized polyvinyl chloride (PVC-U)
4、 casings, for use in well construction.Slot widths as specied here apply whether or not a gravel pack is used.2 Normative referencesThis standard incorporates, by dated or undated reference, provisions from other publications. These nor-mative references are cited at the appropriate places in the te
5、xt, and the titles of the publications are listed below. For dated references, subsequent amendments to or revisions of any of these publications apply to this standard only when incorporated in it by amendment or revision. For undated references, the latest edition of the publication referred to ap
6、plies.DIN 2999-1 Pipe threads for tubes and ttings Parallel internal threads and taper external threads Thread dimensions *)DIN 4925-1 Threaded unplasticized polyvinyl chloride (PVC-U) water well lter pipes and casings DN 35 to DN 100 pipes with Whitworth pipe threadDIN 17455 General purpose welded
7、circular stainless steel tubes Technical delivery conditionsDIN 17456 General purpose seamless circular stainless steel tubes Technical delivery conditionsDIN 59110 Steel wire rod Dimensions and massDIN EN 729-1 Quality requirements for welding Fusion welding of metallic materials Guidelines for sel
8、ection and useDIN EN 729-2 Quality requirements for welding Fusion welding of metallic materials Comprehensive quality requirementsDIN EN 10088-1 Stainless steels Part 1: List of stainless steelsICS 23.040.104935-1Translation by DIN-Sprachendienst.In case of doubt, the German-language original shoul
9、d be consulted as the authoritative text. No part of this translation may be reproduced without the prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).Ref. No. DIN 4935-1 : 200
10、2-06English price group 7 Sales No. 010704.05*) Superseded by DIN EN 10226-1.Page 2 DIN 4935-1 : 2002-06DIN EN 10088-2 Stainless steels Part 2: Technical delivery conditions for general purpose sheet/plate and stripDIN EN 10088-3 Stainless steels Part 3: Technical delivery conditions for semi-nished
11、 products, bars, rods and sections for general purposes (includes Amendment A1 : 1997)DIN EN 10204 Metallic products Types of inspection documentsDIN EN 10226-1 Pipe threads where pressure-tight joints are made on the threads Part 1: Taper external threads and parallel internal threads Dimensions, t
12、olerances and designationDIN EN 10241 Steel threaded pipe ttingsDIN EN ISO 1127 Stainless steel tubes Dimensions, tolerances and conventional masses per unit length (ISO 1127 : 1992)DIN EN ISO 5817 Fusion-welded joints in steel, nickel titanium and their alloys (beam welding excluded) for imperfecti
13、ons (ISO 5817 : 2003)ISO 2768-1 : 1989 General tolerances Part 1: Tolerances for linear and angular dimensions without individual tolerance indicationsAD-Merkblatt (AD Code of practice) B 0 Berechnung von Druckbehltern (Design of pressure vessels) 1)AD-Merkblatt B 6 Berechnung von Druckbehltern Zyli
14、nderschalen unter uerem berdruck (Design of pressure vessels Cylindrical shells subject to external pressure) 1)1 KTW-Empfehlungen (KTW Recommendations) on the use of plastics in contact with drinking water, issued by the Bundesgesundheitsministerium (German Federal Ministry of Health): Gesundheitli
15、che Beurteilung von Kunststoffen und anderen nichtmetallischen Werkstoffen im Rahmen des Lebensmittel- und Bedarfsgegen-stndegesetzes fr den Trinkwasserbereich (Assessment of the standard of hygiene of plastics and other non-metallic materials according to the terms of the German Federal Foodstuffs
16、Act as applied to drinking water), Bundesgesundheitsblatt (German Federal Health Gazette), 1977: 20(1), pp. 1013 and 5661, 20(2), pp. 124129, 1979: 22(3), pp. 213216, 1979: 22(4), pp. 264265, 1985: 28(5), pp. 371374 and 1987: 30(6), p. 1783 Dimensions, designation and designGeneral tolerances shall
17、be class m tolerances as in ISO 2768-1.3.1 Screens3.1.1 Screen dimensionsl2is the effective screen length after assembly, with the socket length, l1, being equal to l2plus the thread length, l3. The maximum length of wire wrapping, l4, shall be 6 000 mm.The minimum effective screen length available
18、is 1 000 mm.1) Obtainable from Carl Heymanns Verlag KG, Luxemburger Strae 449, 50939 Kln, Germany.Page 3 DIN 4935-1 : 2002-06See subclause 3.1.2 for design features.Key to gure:1 Casing2 Screen3 Socket as in DIN EN 102411) l5as in DIN EN 10241.Figure 1: Threaded screen assemblyDesignation of a size
19、DN 100 threaded steel wire wrapped well screen, with a slot width, h1, of 0,2 mm and an effective length, l2, of 6 000:Screen DIN 4935-1 100 0,2 6 000Page 4 DIN 4935-1 : 2002-06Table 1: Screen dimensions and massNominal size DNCheck plug diameter 1)DiameterThread as in DIN 2999-1Mass 2)d1Min.d2d6Thr
20、ead sizeEffective length, l3Screen 3), in kg/mSocket 4), in kg40 39 49 55 41 R/Rp 1 1/2 19,1 2,29 0,5550 50 62 66 52 R/Rp 2 23,4 3,02 0,6065 64 76 82 66 R/Rp 2 1/2 26,7 3,83 0,8080 77 90 95 80 R/Rp 3 29,8 4,39 1,20100 98 114 122 103 R/Rp 4 35,8 5,58 1,90Key:d1Screen outside diameterd2Socket outside
21、diameter (as in DIN EN 10241)d6Screen inside diameter1) The values apply for a check plug length of 100 mm.2) Approximate values; contact manufacturer for more exact values.3) In specifying the mass, a slot width of 0,3 mm has been assumed.4) For socket with thread as in DIN 2999-1.3.1.2 Design feat
22、ures3.1.2.1 GeneralScreens are characterized by the wrapping and rib wire dimensions and the slot width (clear distance between wrapping wires), i.e.h2 h1/ b2 b1whereh2is the wrapping wire width;h1 is the slot width;b2 is the rib wire width;b1 is the spacing (arc length) of rib wires.3.1.2.2 Wrappin
23、g and rib wiresKey1 Wrapping wire2 Rib wireView A shows rib wires of trapezoidal, circular and rectangular section (at manufacturers discretion).Figure 2: Wrapping and rib wires (notation)Page 5 DIN 4935-1 : 2002-06Dimension b1is to be calculated as follows:bdnb162= (1)where n is the number of rib w
24、ires.Table 2: Slot width and wrapping wire widthh1Min.h2Max.Up to 0,500 3,00Above 0,500 3,50Table 3: Rib wire dimensionsNominal size b1*)b2Min.DN 40 to DN 65 7,5 2,0DN 80 to DN 100 7,5 2,5*) b1may be larger, provided the required minimum slot width, h1, is main-tained.Table 4: Limit deviations for h
25、2h2Limit deviations Not more than1,00 to 2,50 t 0,03Above 2,50 up to 3,50 t 0,04Table 5: Radius on wrapping wire, rkh2rkMax.Up to 3,50 0,2503.1.2.3 Slot widthThe slot width shall be as ordered by the customer, but at least 0,15 mm, increasing in 0,05 mm steps.The slot width is subject to limit devia
26、tions of t 0,100 mm. It shall be ensured that these limit deviations are complied with over 90 % of the screen surface area; the actual dimensions do not exceed the above tolerance by more than t 0,05 mm over 9 % of the screen surface area; the actual dimensions do not exceed the above tolerance by
27、more than t 0,10 mm over 1 % of the screen surface area.3.1.3 Free inlet areaThe ratio of the free inlet area to the screen total surface area, f, is to be determined using the following equa-tion:fb hb b h h=+( ) +( )1 11 2 1 2100(2)3.2 CasingsCasings may be made of stainless steel as in DIN 17455,
28、 DIN 17456 or DIN EN ISO 1127, of plastics-coated steel, or may be as in DIN 4925-1 (made of PVC-U).The inside diameter of the casing shall not be less than the relevant check plug diameter specied in table 1.Page 6 DIN 4935-1 : 2002-064 MaterialsThe material, form supplied, properties and nish of s
29、creens shall be as specied in DIN 59110 and DIN EN 10088-1 to DIN EN 10088-3, the steel grade being selected to be compatible with the groundwater quality. Screens shall be pickled and passivated.The manufacturer shall, on request, provide a type 2.1 inspection document (declaration of compliance wi
30、th the order) as specied in DIN EN 10204.5 Requirements5.1 GeneralScreens shall have a continuous slot and shall be manufactured using proled wrapping wire, with the rib wire fused to the wrapping wire at each point of contact.Analysis for adequate strength to resist hydrostatic external pressure sh
31、all be made in accordance with AD-Merkblatt B 6, taking into account the specications of DIN 17455 and AD-Merkblatt B 0.In the analysis, the equivalent wall thickness, te, calculated from the second moment of area of the wrapping wire section and giving due consideration to the free inlet area, shal
32、l be used as the wall thickness; the hydrostatic pressure (assumed to act uniformly on the screen) shall be at least 0,07 bar per metre of casing depth; Rmas in DIN 17455 may be used as the tensile strength (depending on the wire material).The depth of installation and the socket thread (cf. clause
33、6) shall be specied at the time of ordering.5.2 Physiological safetyScreens, casings, ttings and jointing materials shall neither affect the taste, odour or colour of drinking water nor release any harmful substances into it in signicant amounts. Algal or microbial growth in the water shall not be s
34、timulated (cf. the relevant KTW-Empfehlungen) 1.6 Screw threadThe thread used shall be as specied in DIN 2999-1 *).7 WeldingThe contractor shall present a welders qualication test certicate (cf. DIN EN 729-1 and DIN EN 729-2).Welds shall be made to quality level B as in DIN EN ISO 5817.Other relevan
35、t standardsDIN 2000 Guidelines for drawing up requirements for the design, construction, operation and mainte-nance of public drinking water supply systems (DVGW Code of practice)DIN 4925-2 Threaded unplasticized polyvinyl chloride (PVC-U) water well lter pipes and casings DN 100 to DN 200 pipes wit
36、h trapezoidal threadDIN 4925-3 Threaded unplasticized polyvinyl chloride (PVC-U) water well lter pipes and casings DN 250 to DN 400 pipes with trapezoidal threadDIN EN 287-1 Qualication testing of welders Fusion welding Part 1: SteelsDIN EN 10220 Seamless and welded steel tubes Dimensions and masses per unit lengthFor *), see page 1.
