SERVICES OFFERED QUALITY & COMPLIANCE

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2 The name Braithwaite is synonymous with water storage worldwide. During its ninety year period of storage tank manufacture and installation, Braithwaite has gained an enviable reputation for the quality and reliability of its products. The Hot Pressed Steel Sectional Tank is perhaps unique for an industrial product the design although refined over the years, is still essentially the same product that was originally patented in Its continued use provides ample testimony to the virtues of the Braithwaite Hot Pressed Steel Sectional Tank. Throughout the intervening period the tank has given sterling service all around the world. With current examples ranging from the intense heat of Africa and the Middle East, to the extreme cold of Siberia and Antarctica, it continues to be a market leader in many countries providing cost effective engineered solutions to water storage problems. The Braithwaite Hot Pressed Steel Tank is easily recognised by the distinctive star pressing in the centre of the panel, which in addition to providing strength and rigidity is also the Company logo and a registered trade mark. QUALITY & COMPLIANCE Braithwaite ensures quality control through the rigorous application of best working practices and current international standards, confirmed by its accreditation with an EN ISO 9001: 2000 Quality System approved and audited by the Loss Prevention Certification Board (LPCB). Braithwaite has been endorsed by many government bodies, blue chip companies, contractors, consulting engineers, finance institutions and aid agencies. Braithwaite Hot Pressed Steel Tanks are approved by: WRAS for use with water stored at ambient temperature. BS1564: 1975 Type One. WRAS and LPCB for use on automatic sprinkler installations. SERVICES OFFERED Braithwaite offers a full design, fabrication, protective treatment, shipment & erection service for tanks, towers and ancillary items. Design work is in accordance with BS449 or BS5950, including the incorporation of any specified seismic, wind and snow loading to be accommodated. Qualified engineers can be provided to survey & prepare reports on existing tanks & structures, to undertake feasibility studies, to supervise erection or to fully manage construction sites. Braithwaite can supply their own teams of trained subcontractors to carry out all forms of erection, modification or refurbishment. The labour force is fully conversant with the working and safety procedures relating to large construction projects, time constraints imposed by plant shutdowns and the requirements of particular industries. Braithwaite offer their services through the UK and worldwide. ENSURE A CLEAN SUPPLY OF WATER 2

3 HOT PRESSED STEEL TANKS THE CONCEPT Braithwaite Hot Pressed Steel Tanks are formed using massproduced tank plates and prefabricated cleats and stays bolted together on site, to give an infinite range of sizes and capacities, in accordance with British Standard BS1564: 1975 Type One. Though generally square or rectangular in construction, tanks can be provided in a variety of forms to suit particular site conditions or project requirements. The most common deviations are l or T shaped tanks (plan or elevation) and tanks noteched to avoid obstructions. Through a variety of flanging arrangements Braithwaite tanks can be designed to be supported on concrete rafts or consolidated foundations (where headroom is restricted), on grillages at ground level or in plant rooms (providing access to the underside for inspection and maintenance) or elevated on steel or concrete towers (providing a static head of water). Where site access is severely restricted a completely internally flanged tank can be designed, providing access to all connections from within the tank. The modular concept and bolted construction allows for high speed assembly utilising semiskilled labour. This provides obvious client advantages and cost benefits associated with reduced site duration s when considered against traditional concrete or welded steel construction. Refurbishment is relatively straightforward as individual components can be inspected and replaced as required. Similarly, dimensional and capacity alterations can be accommodated with minimal downtime, indeed if requested at concept stage, tanks can be designed for extension in length without interruption to the water supply. Although best known for the storage of potable water, a wide range of liquids can be stored in Braithwaite tanks and the sectional method is also well suited to the storage of solids in granular or flake form. In addition to the construction of storage tanks, the tank plate has provided our engineers with solutions to a variety of challenges and has been used in the construction of bund walls, blast walls, retaining structures, access shafts, baffles, weirs, pontoons, jetties and even a floating heliport! FEATURES & BENEFITS Modular bolted construction provides: Infinite range of sizes and configurations. Excellent flexibility to adapt as storage requirements change. Ability to be installed in areas with restricted access. Quick and simple assembly using hand tools. Highly economical transportation. Hot pressing of tank plates using matched tools ensures: Close control over quality of product. Consistency of tank plate size. No requirement for welding corners of plates. No distortion as heat treatment dissipates stress. THINK TANK THINK BRAITHWAITE All steel construction provides: Inherent strength and durability of the raw material. High resistance to damage during transit and assembly. Excellent substrate for a wide range of protective finishes. Long term life expectancy. 3

4 TANK COMPONENTS TANK PLATES The standard tank plates are 1000 or 1200mm square, hot pressed from mild steel plates in one piece and embossed with the distinctive star pressing. Thickness of panel ranges from 4mm to 6mm, determined by tank depth and contents. Non standard plates can be fabricated to provide full versatility for specific requirements. COVERS Covers can be provided for either interior or exterior conditions and are designed to withstand superimposed loadings in accordance with the requirements of BS449 and loading imposed by maintenance personnel. Suitable jointing materials ensure covers are dust or weatherproofed to suit their application. Special covers can be constructed from flanged tank plates to allow for pressure differentials and advice can be provided to ensure suitability for each application. DIVISIONS To enable maintenance of the tank without interruption of the water supply, tanks can be fitted with divisions. Divisions are constructed from standard tank plates and are designed to operate with either compartment empty. It is advisable for all tanks storing 5000 Litres and above to be fitted with a division. FLOAT VALVE CHAMBERS Standard covers are fabricated from 3mm thick steel plate and are not designed to withstand pressures other than those described above. In order to obtain added capacity in covered tanks or to provide a type A air gap for compliance with the WRAS, preventing back siphonage, float valve chambers can be supplied. Theses are fixed to the cover plates and enable the normal allowance for freeboard to be reduced. Where supplies to the tank are derived from more than one source, multi-float valve assemblies can be mounted in a single box. It is possible that the use of a ball valve box will necessitate increasing the minimum distance between the cover and the ceiling above it. CLEATS & STAYS All internal fittings are fabricated from steel and carefully designed to ensure the strength and rigidity of each tank size. Where special applications make the use of internal staying impossible, angle and channel stiffeners can be provided externally. BOLTS, NUTS & WASHERS All bolts used in the construction comply with the requirements of BS For export contracts, a complete set of spanners is provided, together with a percentage of spare bolts, nuts and washers. JOINTING MATERIALS A simple type of strip jointing material is used between the flanges of the tank plates, under the tank cleats and for sealing the cover plates. Standard jointing materials are available for a variety of tank contents, including potable water and fuel oils. Full information is required at the enquiry stage to ensure complete satisfaction. When the normal jointing materials cannot be used it is possible to seal weld the internal seams of Braithwaite tanks. INSULATION Tanks can be site insulated using the unique BelTherm 70 system. PROTECTIVE TREATMENT Braithwaite offer two standard shop finishes: Hot dipped galvanising to BS EN ISO 1461: Blast clean to BS 7079 second quality followed by one coat of two pack epoxy zinc phosphate primer. Non standard finishes can be provided on receipt of specific requirements, including sprayed zinc or aluminium, G.R.P. and hot applied bituminous enamel. Site applied paint systems can be provided to BS 5493, which give typical times until first maintenance in excess of 20 years. For drinking water applications Braithwaite use WRAS approved products. The key to maximising the life of a pressed steel tank is the choice of its protective coating system and an effective maintenance programme. Braithwaite can offer advice on the most suitable system for a given application. MODEL SPECIFICATIONS AVAILABLE 4

5 TANK FITTINGS STANDARD FITTINGS Braithwaite Hot Pressed Steel Sectional Tanks fitted with covers feature the following fittings as standard: 460mm diameter access manway with hinged lid. Screened cowl ventilator. Internal access ladder for tanks deeper than 1220mm. OPTIONAL FITTINGS External ladders and handrails to BS Float valve chambers. Contents gauges. Sumps. Access manways to suit a variety of different applications. Anti-vermin screens for overflow and warning pipes to comply with Water Byelaw 30. Spill over weir boxes to provide type A air gaps, in accordance with BS 6281: Part 1. PIPE CONNECTIONS Three basis types of pipe connection are used on Braithwaite tanks: BSP tapped sockets for screwed pipework up to 76mm bore. Pads with studs for pipework flanged to BS BSP tapped flanges for screwed pipework. Pipe connections are normally fitted to the tank plates prior to despatch. PIPEWORK & VALVES The selection of suitable pipework and valves for Braithwaite Pressed Steel Tanks should always be considered at the planning stage so that they can be ordered with the tank, ensuring that they are available in good time and suitable for the tank concerned. The Rising Main (1). This may enter the tank by a right angled bend passing through a tank plate (at the top). Alternatively, a vertical standpipe fixed to the bottom of the tank can be used. Control of Flow (2). This can be affected by an equilibrium float valve or other suitable device. Outlet Services (3). These should be taken from the bottom of the tank, preferably via a rose strainer. Overflows (4). A bellmouth fitted to a vertical standpipe fixed to the bottom of the tank is recommended. Alternatively, a right angled bend passing through a tank plate is suitable. Either should be positioned below the level of the supply valve. Washout (5). This is not essential but is recommended. An external pipe connection should be used, the pipe being arranged to join the overflow pipe. A sluice valve must be incorporated in the short pipe run before joining the overflow. Pipework, Valves etc. These should be grouped as near together as possible for ease of operation. Such grouping for tanks supported on towers enables control to be made from the access ladder or a purpose made platform. Pipes should be supported at or below ground level on duck foot bends (6) which are in turn supported on concrete footings (7). Close grouping of pipework and valves is recommended for tanks divided into two compartments so that a single control point can serve both. It is not good practice for pipes to pass through the cover plates of tanks. 5

6 TANK CONFIGURATIONS EXTERNALLY FLANGED TANKS (1) Wherever possible externally flanged tanks should be utilised because: (1) assembly bolts in the tank sides and base are external for ease of assembly, maintenance and inspection. the majority of the tanks contents can be drained by using a washout connection in the base of the tank. Tanks of externally flanged construction require: 500mm clearance all around and underneath the tank for assembly and maintenance. 700mm clearance above the cover for access into the tank. Tank with external flanges throughout INTERNALLY FLANGED BASE TANKS (2) (2) Where head room within a building is restricted, Braithwaite offer the option of a tank with externally flanged sides and an internally flanged base. Due to the base plates being inverted: the contents of the bottom 82mm of the tank cannot be used. the flange bolts in the tank base are accessible from within the tank. maximum height of tank is 3 panels i.e. 3660mm or 3000mm high. Tanks of this type of construction require: 500mm clearance all around the tank for assembly and maintenance. 700mm above the cover for access into the tank. TOTALLY INTERNALLY FLANGED TANKS (3) Tanks which are totally internally flanged can be used where it is essential to make full use of a confined site. Due to the flange arrangement: the contents of the bottom 82mm of the tank cannot be used. All the flange bolts are accessible from within the tanks. The maximum height is 3810mm or 3150mm, i.e. 3 panels plus 150mm. The overall length and width of the tank is increased by 300mm. Tanks with this flange arrangement require: Tank with internal flange to the base and external flanges to the sides Tank with Internal flanges throughout (3) A minimum of 25mm clearance on 3 sides, with 500mm clearance on the fourth side. 700mm above the cover for access into the tank. Note: vertical walls in detail (3) show typical site restrictions 6

7 TANK SUPPORTS EXTERNALLY FLANGED TANKS (A) & (B) Dwarf walls in brick or concrete form the most economical supports and should be built in one direction only beneath each seam of the tank. They should exceed the length or width of the tank by 300mm overall (see detail A). For tanks exceeding 2440mm in height a galvanised mild steel capping flat should be provided between the top of the wall and the base of the tank. An alternative method of support is by universal beams positioned on top of cross walls running in the other direction (see detail B). (A) Walls are to be levelled to +/-3mm with no local high spots over 1mm (B) Steel beams are to be levelled to +/-3mm Allowable deflection 1/500th of span (C) Floor to be levelled to +/-3mm No local high spots over 1mm (D) Externally flanged tank supported on steel grillage Steel beams are to be levelled to +/-3mm Allowable deflection 1/500th of span Tank with Internal flanges throughout Tank with external flanges to the side and internal flanges to the base. TOTALLY INTERNALLY FLANGED & INTERNALLY FLANGED BASE TANKS (C) & (D) Generally these types of tanks are supported on consolidated foundations or concrete rafts, levelled to +/-3mm, with no local high spots over 1mm. The overall dimension of the slab should be 300mm greater than the nominal plan size of the tank. A layer of bituminous sand 50mm thick nullifies any unevenness in the concrete raft and protects the base of the tank against corrosion. Alternatively they can be supported on universal beams positioned in one direction only beneath each seam of the tank. If a totally internally flanged tank is supported in this manner dual beams are required under division walls. 7

8 TYPICAL TANK CAPACITY CHARTS NOMINAL TANK CAPACITY IN LITRES 1000mm PLATES NOMINAL TANK CAPACITY IN LITRES 1220mm PLATES HEIGHT OF TANK (mm) LENGTH BREADTH (mm) (mm) ,675 2,529 3, ,710 3,488 5,266 7, ,599 5,301 8,003 10, ,561 7,263 10,965 14, ,412 11,038 16,664 22, ,263 14,813 22,362 29, ,225 16,775 25,324 33, ,038 22,512 33,985 45, ,813 30,210 45,608 61, ,588 37,909 57,231 76, ,324 47,570 71,816 96, ,061 57,231 84, , ,760 68, , , ,459 80, , , ,158 92, , , ,120 94, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,882 HEIGHT OF TANK (mm) LENGTH BREADTH (mm) (mm) ,547 3,144 4,740 6, ,197 6,496 9,795 13, ,846 9,848 14,851 19, ,606 13,424 20,242 27, ,015 20,351 30,668 41, ,424 27,279 41,134 54, ,183 30,854 46,525 62, ,351 41,357 62,362 83, ,279 55,434 83, , ,206 69, , , ,893 87, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,113 NOTES: 1) The nett capacities in these tables are based on actual internal dimensions and assume the tanks to be full to the brim. 2) The capacities given in BS1564 are based on the nominal dimensions - the capacity of a metre cube being 1000 litres. - the capacity of a 1220mm cube being 1815 litres. 3) For conversion to imperial gallons divide the figure shown in litres by ) The above represents a typical range only with many alternative sizes being available. 5) To obtain the external measurements of the tank the following allowances should be added to the dimensions shown above: FLANGE ARRANGEMENT LENGTH BREADTH HEIGHT EXTERNALLY FLANGED +88mm +88mm +44mm INTERNALLY FLANGED BASE +88mm +88mm +82mm TOTALLY INTERNALLY FLANGED +300mm +300mm +150mm In line with our policy of continual improvement, the Company reserves the right to change specifications without notice. BRAITHWAITE ENGINEERS LTD NEPTUNE WORKS, USKWAY, NEWPORT, SOUTH WALES, NP20 2UY. U.K. Telephone: +44 (0) Facsimile: +44 (0) tanks@braithwaite.co.uk Braithwaite Engineers Limited is a member of the ROWECORD GROUP