1、May 2012DEUTSCHE NORM DIN-Normenausschuss Wasserwesen (NAW)DIN-SprachendienstEnglish price group 17No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for Ge
2、rman Standards (DIN-Normen).ICS 91.140.60!$lr“1987379www.din.deDDIN 1988-300Codes of practice for drinking water installations Part 300: Pipe sizing; DVGW Code of practice,English translation of DIN 1988-300:2012-05Technische Regeln fr Trinkwasser-Installationen Teil 300: Ermittlung der Rohrdurchmes
3、ser; Technische Regel des DVGW,Englische bersetzung von DIN 1988-300:2012-05Directives techniques pour installations deau potable Partie 300: Calcul du diamtre des tuyaux; Directive technique DVGW,Traduction anglaise de DIN 1988-300:2012-05Together withDIN EN 806-3:2006-07,supersedesDIN 1988-3:1988-
4、12;supersedesDIN 1988-3 Supplement 1:1988-12www.beuth.deDocument comprises 44 pages03.16 DIN 1988-300:2012-05 2 A comma is used as the decimal marker. Contents Page Foreword . 3 1 Scope . 5 2 Normative references . 5 3 Terms, symbols and units . 6 4 Sizing principles . 11 4.1 General . 11 4.2 Pipe f
5、riction . 11 4.3 Individual head losses . 13 5 Sizing of cold and hot water pipes 14 5.1 General . 14 5.2 Design and total flow rates 14 5.2.1 Design flow rate 14 5.2.2 Determining the total flow rate 17 5.3 Determining the peak flow rate . 18 5.4 Determining the available friction loss . 20 5.4.1 G
6、eneral . 20 5.4.2 Percentage head loss due to individual head losses a. 20 5.4.3 Total pipe length lges. 21 5.4.4 Minimum supply pressure . 21 5.4.5 Head loss due to difference in elevation pgeo21 5.4.6 Sum of head losses in appliances 21 5.5 Pipe sizing for the hydraulically most unfavourable flow
7、path . 23 5.6 Flow balancing to obtain the hydraulically more favourable flow path 24 5.7 Special considerations concerning circulation main branch pipe of usage units 24 6 Design of circulation systems . 24 6.1 General . 24 6.2 Downfeed systems . 25 6.2.1 Heat losses and flow rates . 25 6.2.2 Diame
8、ter of circulation pipes and pump pressure 27 6.3 Upfeed systems 28 6.4 Smart loop systems 29 6.5 Balancing the system . 29 7 Documentation 29 7.1 General . 29 7.2 Hot and cold water pipes . 29 7.3 Circulation systems 30 Annex A (informative) Comparable pipe nominal sizes and resistance coefficients
9、 for fittings and valves of dissimilar materials 32 Annex B (informative) Presentation of design assumptions . 43 Bibliography . 44 DIN 1988-300:2012-05 3 Foreword This standard has been prepared by Working Committee NA 119-04-07 AA Husliche Wasserversorgung of the Normenausschuss Wasserwesen (Water
10、 Engineering Standards Committee). In response to the publication of European Standards on drinking water installations developed by Technical Committee CEN/TC 164 “Water supply”, which have been adopted as national German Standards, the German working committee decided to review the content of the
11、DIN 1988 series “Codes of practice for drinking water installations” with the intention of preparing a comprehensive and consistent set of standards. To make up for the fact that the standards developed at European level do not reach the depth required by users in Germany, it was necessary to develo
12、p supplemental German specifications, which have been published again as the 1988 series for reasons of consistency. In order to distinguish the “new” DIN 1988 series from the previous one, the individual parts of the series have been assigned three-digit numbers. Currently, the DIN 1988 series of s
13、tandards consists of the following parts, under the general title Codes of practice for drinking water installations: Part 100, Protection of drinking water, drinking water quality control; DVGW Code of practice Part 200, Installation Type A (closed system) Planning, components, apparatus, materials
14、; DVGW Code of practice Part 300, Pipe sizing; DVGW Code of practice Part 500, Pressure boosting stations with RPM-regulated pumps; DVGW Code of practice Part 600, Drinking water installations in connection with fire fighting and fire protection installations; DVGW Code of practice For more than two
15、 decades, designers and installers have had positive experience in practice with the calculation methods described in DIN 1988-3:1988-12. In light of this, it was decided to adopt the major aspects for a differentiated hot and cold water pipe sizing in the present standard, updating, however, a numb
16、er of parameters such as the design and peak flow rates, resistance coefficient, individual head losses, etc. (see Amendments clause below). Moreover, in this standard circulation systems are sized taking into account head losses along pipe runs, the aim being to ensure that a minimum hot water temp
17、erature of 55 C at the minimum water consumption is maintained throughout the system. Amendments This standard differs from DIN 1988-3:1988-12 and DIN 1988-3 Supplement 1:1988-12 as follows: a) lower design flow rates are specified for dishwashers and washing machines; b) different flow rates at pea
18、k demand are specified in accordance with current conditions of usage, and the concept of usage units has been introduced to cover downstream peak loads (e.g. those at storey level) more adequately; c) the “simplified method” is no longer permitted (e.g. that in which the pressure losses are estimat
19、ed by means of individual head losses); reference values for individual head losses may only be used in product-neutral tendering; DIN 1988-300:2012-05 4 d) the sizing procedure is to start downstream of the water meter, using the minimum pressure as specified by the water supplier; e) checking the
20、plausibility of the reference values as specified in this standard (e.g. for minimum flow pressure) by comparing them with the manufacturers data; f) circulation main branch pipes are to be sized by a detailed method on the basis of usage units; g) the sizing of circulation systems has been modified
21、 to meet hygienic requirements at minimum technical and energetic cost; h) material values are to be taken into consideration as a function of the temperature. Previous editions DIN 1988: 1930-08, 1940-09, 1955-03, 1962-01 DIN 1988-3: 1988-12 DIN 1988-3 Supplement 1: 1988-12 DIN 1988-300:2012-05 5 1
22、 Scope This standard applies, in conjunction with the DIN 1988 series and the DIN EN 806 series, to the design, installation, modification, maintenance and operation of drinking water installations in buildings and on properties, and serves as a basis for sizing pipes and for determining the size of
23、 components in circulation systems (circulation pipes, pumps, valves). The sizing of cold and hot water pipes aims at selecting the smallest possible pipe inside diameter that ensures the minimum flow rate at all draw-off points during times of peak demand. The detailed calculation method as describ
24、ed in this standard is suitable for all types of buildings. NOTE For residential buildings with up to six dwellings, the sizing of cold and hot water pipes may also be in accordance with DIN EN 806-3 subject to the mains pressure being adequate and an acceptable water hygiene being ensured. 2 Normat
25、ive references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. DIN 1988 (all parts), Codes of pra
26、ctice for drinking water installations DIN EN 297, Gas-fired central heating boilers Type B boilers, fitted with atmospheric burners of nominal heat input not exceeding 70 kW DIN EN 625, Gas-fired central heating boilers Specific requirements for the domestic hot water operation of combination boile
27、rs for nominal heat input not exceeding 70 kW DIN EN 806 (all parts), Specifications for installations inside buildings conveying water for human consumption DIN EN 12541, Sanitary tapware Pressure flushing valves and automatic closing urinal valves PN 10 DIN EN 14124, Inlet valves for flushing cist
28、erns with internal overflow DIN EN 14154-1, Water meters Part 1: General requirements DIN EN 15091, Sanitary tapware Electronic opening and closing sanitary tapware DIN EN 50242, Electric dishwashers for household use Methods for measuring the performance DIN EN 60456, Clothes washing machines for h
29、ousehold use Methods for measuring the performance DIN EN ISO 3822-2, Acoustics Laboratory tests on noise emission from appliances and equipment used in water supply installations Part 2: Mounting and operating conditions for draw-off taps and mixing valves DVGW-Arbeitsblatt (DVGW Code of practice)
30、W 575, Ermittlung von Widerstandsbeiwerten fr Form- und Verbindungsstcke in der Trinkwasser-Installation (Determination of resistance coefficients for pipe fittings in drinking water installations1)1) Obtainable from Wirtschafts- und Verlagsgesellschaft Gas und Wasser mbH, P.O. Box 140151, 53056 Bon
31、n, Germany. DIN 1988-300:2012-05 6 3 Terms, symbols and units Table 1 lists the most important terms, symbols, units and definitions as used in this standard. Table 1 Terms, symbols, units, definitions Term Symbol or abbreviation Unit Definition Percentage head loss due to individual head losses a %
32、 EREpppa+=Pipe cross-sectional area A m24/2idA = Constants a, b, c Constants for the peak flow rate Specific heat capacity of water cWkJ/(kg K) Energy required to raise the temperature of 1 kg of water 1 K (4,18 kJ/(kg K) Pipe outside diameter (of lagged pipe) D mm Outside diameter of a lagged hot w
33、ater pipe, see Equation (14) Pipe outside diameter damm Outside diameter of a hot water pipe, see Equation (15) Pipe inside diameter dimm Minimum pipe inside diameter di,minmm Minimum inside diameter of a pipe of a given nominal size Geodetic height difference hgeom Difference in elevation between t
34、wo points in a pipe run Hydraulic roughness k mm Assumed absolute roughness of pipe inner wall in service condition (empirical value) Pipe length l m Length of a pipe section Pipe length (hot water pipe) lwm Length of a hot water pipe section up to most distant draw-off point (see Equation (22) for
35、circulation pipes) Pipe length (basement) lwKm Length of a hot water pipe section in the basement Pipe length (shaft) lwSm Length of a hot water pipe section for circulation pipes in a shaft Total pipe length lgesm Length of pipe run from the point of entry of service pipe to the relevant tap Pipe l
36、ength (circulation) lzm Length of circulation pipe (see Equation (22) for circulation pipes) Flow rate, volume flow Vl/s, l/h Ratio of water volume to time; volume flow for water fed to a junction DIN 1988-300:2012-05 7 Table 1 (continued) Term Symbol or abbreviation Unit Definition Flow rate in bra
37、nch aVm3/h Volume flow in a branch (of a circulation system) Flow rate in run dVm3/h Volume flow in pipe run (of a circulation system) Flow rate in appliance gVm3/h Volume flow in an appliance at a given operating point Upper flow rate oVl/s Flow rate through a tap at a pressure of 0,3 MPa Flow rate
38、 of circulation pump PVm3/h Volume flow through circulation pump under design conditions Minimum flow rate minVl/s Rate of flow through a tap that still permits it to fulfil its function Continuous flow (Continuous demand) DVl/s Rate of flow at a draw-off point with continuous demand (for demands 15
39、 min) Nominal flow rate for filter NVm3/h Flow through filter at a head loss of 0,02 MPa (specified on nameplate) Design flow rate RVl/s Design rate of flow through a tap Total design flow rate RVl/s Sum of all design flow rates Peak flow rate SVl/s Flow rate as a basic parameter in hydraulic design
40、 and allowing for the simultaneous demand of water likely to be expected in service Minimum flow pressure pminFlhPa MPa Static pressure required at a water tap to achieve the minimum flow rate Minimum supply pressure pminVhPa MPa Minimum static pressure at junction of service pipe and water main (ac
41、cording to information provided by public water supplier) DIN 1988-300:2012-05 8 Table 1 (continued) Term Symbol or abbreviation Unit Definition Minimum pressure downstream of water meter pminWZhPa MPa Minimum static pressure immediately downstream of water meter at peak demand Specified head loss p
42、ghPa MPa Pressure loss across appliance for a given operating pointHead loss due to difference in elevation pgeohPa MPa geogeohgp = Delivery pressure of circulation pump pPhPa MPa Difference between downstream (outlet) pressure and upstream (inlet) pressure of circulation pump at PVHead loss in an a
43、ppliance pAphPa MPa Appliances include water meters, filters, softeners, chemical dosing systems, group supply water heaters Available pressure difference pges,vhPa MPa Pressure difference allowing for friction in pipe and individual head losses Head loss due to individual head losses along pipe run
44、 pE= Z hPa MPa =Ep2v2Head loss due to frictional resistance in a pipe section pRhPa MPa lRp =R Head loss in circulation main branch pipe pRinghPa MPa To be taken into account when determining Rvusing Equations (10) and (14)Head loss due to resistance of check valve pRVhPa MPa Not covered by value ow
45、ing to set pressure Head loss due to resistance of circulation control valve when fully open pZRVhPa MPa See manufacturers instructions! Head loss due to resistance of water meter pWZhPa MPa To be determined at peak demand, in accordance with DIN 1988-300 Head loss due to resistance of service pipe
46、pHALhPa MPa Head loss at peak demand (as in this standard) along pipe length from main supply pipe to water meter according to DIN 1988-300 Head loss due to resistance of group supply water heater pTEhPa MPa To be determined at peak demand at water heater (see Table 5 for reference values) DIN 1988-
47、300:2012-05 9 Table 1 (continued) Term Symbol or abbreviation Unit Definition Usage unit NE Room with draw-off points in residential buildings (e.g. bathroom, kitchen, utility room) or in non-residential buildings if used for living purposes (bathroom in a hotel, retirement home, ward of a hospital,
48、 etc.). Usage is defined as the condition under which water is drawn off at not more than two draw-off points at the same time Specific heat flow rate w.q W/m Heat loss of lagged hot water pipe per metre of pipe length Heat loss in circulation pipe (section downstream of junction) zQW Heat loss that determines the extent to which cold and hot water are to be mixed in the main circulation pipe downstream of a hot/cold water junction Heat loss in branching pipe aQW Heat l
