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1、BRITISH STANDARD BS 8005-2: 1987 Sewerage Part 2: Guide to pumping stations and pumping mains UDC 628.213 Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:10:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8005-2:1987 This British Standard, having been prepar
2、ed under the direction of the Civil Engineering and Building Structures Standards Committee, was published under the authority of the Board of BSI and comes into effect on 31 December 1987 BSI 02-2000 First published as CP 2005 December 1968 First Part revision as BS 8005-2 December 1987 The followi
3、ng BSI references relate to the work on this standard: Committee reference CSB/5 Draft for comment 84/11182 DC ISBN 0 580 15992 2 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Civil Engineering and Building Structures Standards Committ
4、ee (CSB/-) to Technical Committee CSB/5, upon which the following bodies were represented: Association of Consulting Engineers Association of County Councils Association of District Councils British Ceramic Research Ltd. British Coal British Plastics Federation British Precast Concrete Federation Lt
5、d. British Tunnelling Society Clay Pipe Development Association Limited Concrete Pipe Association Construction Industry Research and Information Association Convention of Scottish Local Authorities County Surveyors Society Department of the Environment (Property Services Agency) Department of Transp
6、ort (Highways) Federation of Civil Engineering Contractors Fibre Cement Manufacturers Association Limited Health and Safety Executive Hydraulics Research Station Ltd. Institute of Water Pollution Control Institution of Civil Engineers Institution of Environmental Health Officers Institution of Publi
7、c Health Engineers Institution of Structural Engineers Institution of Water Engineers and Scientists Royal Institute of British Architects Scottish Development Department Trades Union Congress Water Authorities Association Water Research Centre The following bodies were also represented in the draft
8、ing of the standard, through subcommittees and panels: British Effluent and Water Association British Pump Manufacturers Association Amendments issued since publication Amd. No.Date of issueComments Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:10:16 GMT+00
9、:00 2006, Uncontrolled Copy, (c) BSI BS 8005-2:1987 BSI 02-2000i Contents Page Committees responsibleInside front cover Forewordii Section 1. General 1Scope1 2Definitions1 3Abbreviations1 Section 2. Range of components and appliances 4General2 5Pumps2 6Prime movers and drives3 7Controls and electric
10、al equipment5 8Pipework and valves7 9Miscellaneous8 Section 3. Design of pumping stations 10General9 11Health, safety and welfare design features9 12Maximum and minimum pumping rates9 13Pumping heads9 14Number and size of pumpsets10 15Layout of pumpsets, pipework, control equipment and ancillary pla
11、nt11 16Substructure design12 17Wet wells12 18Ventilation, smell and noise13 19Lifting facilities13 20Superstructure14 21Environment and access14 Section 4. Design of pumping mains 22Velocities of flow15 23Diameter15 24Number of mains15 25Pressures15 26Valves16 27Profiles16 28Discharge arrangements16
12、 29Anchorages16 30Control of septicity17 Publications referred toInside back cover Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:10:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8005-2:1987 ii BSI 02-2000 Foreword This British Standard has been prepared
13、under the direction of the Civil Engineering and Building Structures Standards Committee and is directed at general engineering practitioners who may either be embarking on a career in sewerage or be dealing with a particular aspect for the first time. It is not intended to be exhaustive in any fiel
14、d but sets out to present guidance on basic principles and good practice, indicating where a more detailed and comprehensive study may be made. BS 8005 supersedes and enhances CP 2005:1968, which is withdrawn, although some of the material incorporated is a restatement or a revision of the earlier t
15、ext. BS 8005 gives guidance on the planning, design, construction, operation and maintenance of works to convey sewage, including storm sewage, surface water and trade effluents to a sewage treatment works, tidal waters or other final place of disposal. Recommendations are given for the repair, reno
16、vation and replacement of sewers. Many end users of this British Standard, such as governments, public authorities, sewerage authorities and consultants, issue their own recommendations and specifications for sewerage which BS 8005 is intended to complement rather than replace. BS 8005-0 directs the
17、 reader to sources of more detailed information, particularly on important and specialized fields such as health and safety. It should be regarded as supplying essential background information for the other Parts of BS 8005. BS 8005 is to be published in six separate Parts, as follows. Part 0, Intro
18、duction and guide to data sources and documentation; Part 1, Guide to new sewerage construction; Part 2, Guide to pumping stations and pumping mains; Part 3, Guide to sewers in tunnel1); Part 4, Guide to design and construction of outfalls; Part 5, Guide to rehabilitation of sewers1). It has been no
19、ted that substantial one-part codes and guides take a long time to revise and if they are reviewed at infrequent intervals, they tend to become out of date quickly, especially in a field where technological development is rapid. It is intended therefore to keep a constant watch on new developments a
20、nd to update BS 8005, Part by Part, as soon as the work can be justified. BS 8301 sets out recommendations for building drainage and, while it relates generally to smaller pipelines, there is some overlap between it and BS 8005. BS 6297 gives recommendations for the design and installation of small
21、sewage treatment works and cesspools. Apart from Part 0, which is directed more specifically at the UK sewerage field, BS 8005 is for use both in the UK and, in appropriate circumstances, overseas. Suggestions for the improvement of any Part of BS 8005 will be welcomed by the Secretary of CSB/5 at 2
22、 Park Street, London W1A 2BS. A British Standard dose not purport to include all the necessary provision 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 p
23、ages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 18, 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 cov
24、er. 1) In preparation. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:10:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8005-2:1987 BSI 02-20001 Section 1. General 1 Scope This Part of BS 8005 provides guidance on the components, appliances and design of p
25、umping stations and pumping mains. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. The titles of British Standards not referred to in this Part of BS 8005 but of interest as dealing with closely associated subjects are listed in Appendix A of BS 8
26、005-1:1987. Other publications that may be of interest are listed in Appendix B of BS 8005-1:1987. 2 Definitions For the purposes of this Part of BS 8005 the definitions given in BS 8005-0 apply. 3 Abbreviations For the purposes of this Part of BS 8005 the abbreviations given in BS 8005-1 apply. Lic
27、ensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:10:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8005-2:1987 2 BSI 02-2000 Section 2. Range of components and appliances 4 General The type and size of sewage pumping stations and equipment depend upon their dut
28、ies, location and any special operational requirements, such as remote or automatic control. This section covers the main range of components, whilst methods of installation and housing are dealt with in section 3. Components and appliances are required to be reliable, robust, easy to maintain and a
29、ppropriate for pumping water and other liquids. In addition, the aggressive nature of sewage, with its variable solid content and possibility of toxicity and explosive gases, calls for a high degree of caution and the adoption of the latest safeguards to meet all possible hazards. 5 Pumps 5.1 Genera
30、l Pumps for handling sewage should be unchokeable and wear resisting. They may be divided broadly into four groups: rotodynamic; reciprocating; pneumatic and Archimedean screw. (See also BS 6297.) 5.2 Rotodynamic pumps Rotodynamic pumps are relatively cheap to buy, of small overall dimensions in rel
31、ation to capacity, light in weight and can be arranged vertically or horizontally. They may vary from moderate to high efficiency according to the size of the pump, type of impeller and the head/quantity characteristic of the duty to be performed. All types of rotodynamic pumps afford a high degree
32、of flexibility. Both quantity and head can be varied by changing the speed and/or diameter of the impeller. When two or more pumps are required to discharge in parallel to a common rising main the head/quantity characteristics should be studied in order to obtain stable conditions and a good overall
33、 efficiency. This important group of pumps is divided into three types. a) The centrifugal pump. The capacity of traditional dry well centrifugal pumps for reasonably economic working may vary from a minimum of about 7 L/s up to 700 L/s and more, with heads varying from 3 m to about 45 m. With small
34、 to medium capacities the pump should be of the unchokeable type wherein any solid, up to a maximum of about a 100 mm sphere, that may enter the pump suction will be passed through the pump. The recessed impeller type of centrifugal pump (also called vortex or torque flow pumps), although of lower e
35、fficiency, is less likely to be affected by fibrous material and can be easier to open up for maintenance. Submersible centrifugal sewage pumps are available for a similar range of duties, either as stationary submerged units or as transportable submersible installations. They are self-priming with
36、both pump and motor totally submersible and are accordingly suited for use in wet wells or in dry wells where there is a flooding risk. Cooling is a problem in a dry well and special design precautions may be necessary. The discharge connection of the pump is adaptable for either a flexible hose or
37、static pipework, and the electric motors are available certified for use in a hazardous area in accordance with BS 5345. For wet well installations submersible centrifugal pump units are available which will slide down guides and seat automatically on the permanent discharge connection. The weight o
38、f the pump forces the mating flanges into contact thus providing a seal on the discharge side. Centrifugal disintegrator pumps may be used to assist the treatment of the sewage. Running and maintenance costs are higher, especially if they are on a combined sewerage system where there is a high conte
39、nt of grit in the sewage. b) The mixed flow pump. The mixed flow pump is more efficient where the volume of sewage to be pumped is large and where the head lies in the range of 6 m to 18 m. c) The axial flow or propeller-type pump. The axial flow pump is suitable where large volumes of sewage have t
40、o be pumped against low heads. The above pump classifications are generalized and, in particular, the mixed flow design of impeller overlaps the head ranges of both axial and straight centrifugal pumps. Many modern design unchokeable pumps have mixed flow impellers but are of relatively low efficien
41、cy. High efficiency centrifugal pumps, mixed flow pumps and axial flow pumps should only be installed in association with preliminary screening or the reduction of the coarser suspended solids. For very small flows a small high efficiency centrifugal pump can be used as part of a sewage diverter whe
42、re the coarser solids are prevented from passing through the pump. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 06:10:16 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 8005-2:1987 BSI 02-20003 5.3 Reciprocating pumps The reciprocating pump is heavy and of larg
43、e dimensions in relation to its capacity. It is reliable, efficient when first installed, and is capable of operating with a high suction lift and of discharging against very high heads. It is susceptible to choking, heavy wear and tear, and loss of efficiency through wear and valve jamming. The rec
44、iprocating pump may be either of single-acting or double-acting type. Reciprocating pumps are more expensive in first cost than other types. They are expensive to maintain and therefore are rarely used for pumping crude sewage. Preliminary screening of sewage to remove large solids is advisable. As
45、a safeguard against excessive pressure a bypass is often provided between delivery and suction. This should be combined with a pressure relief valve. An alternative is to relieve the discharge to the suction well. A reciprocating pump requires a slow speed drive; this is provided through gearing bet
46、ween the prime mover and the pump. A steady rated discharge is maintained over a wide variation in head. Discharge is altered by varying the speed. 5.4 Pneumatic pumps The pneumatic ejector, whether of the automatically filled vessel or the air lift type, is suitable where reliability and ease of ma
47、intenance are of greater importance than overall efficiency, and where a small quantity of sewage is to be pumped against a relatively small head. The installation usually comprises an ejector together with an automatic self-starting air compressor, with provision for air storage. In special situati
48、ons two ejectors should be provided to facilitate repairs; where breakdown would have serious results, a second air compressor should be provided. It is possible to serve several ejector stations from one central air compressing station if the distances are not too great. 5.5 Archimedean screw pumps
49、 Archimedean screw pumps are basically screws revolving at a fixed speed. They provide a steady rate of pumping and high efficiency over a wide range of flows and are also effective in pumping varying flows. They are suitable for lifting large volumes of unscreened sewage or storm water against low heads. The actual volume lifted for any particular diameter is dependent on the speed of rotation and on the angle of inclination; the greater the angle the less the rate of discharge. The angle of inclination varies from a minimum of 27 to the horizontal to a maximum o