The Braithwaite profile steel welded tank is designed to store large quantities of liquid, especially in remote or exposed locations. This tank is WRAS approved for the storage of potable water. Delivered in sections for welding on-site, profile steel welded tanks produce extremely strong and reliable storage vessels of unlimited capacity. They are increasingly specified by large volume users such as water authorities, hospitals, breweries and defence establishments.

FEATURES

Rectangular shape makes best use of available space. Profile plates offer great strength with pleasing appearance. May be installed at or below ground level or on towers. Tanks up to 5 metres high do not need internal supports apart from roof posts. Clear interior allows easy inspection, draining and painting. Manways, pipe connections and other fittings may be fitted and welded on site for positional accuracy. External and internal surfaces may be treated with a protective coating to suit most environments.

The tank design can be tailored to suit individual requirements, taking into account the specific gravity of the liquid being stored, its pH value and temperature. HEALTH & SAFETY Our safety consultants regularly visit our sites to report on working practices and equipment standards. This ensures that site work is performed in a safe and workmanlike manner. QUALITY ASSURANCE Braithwaite are certified to BS EN ISO 9001: 2000 and we pride ourselves on our commitment to both our quality of service and our products.

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SPECIFICATION, DESIGN & MATERIAL

LOADINGS (i) Tank cover (imposed loading):

BS6399, Part 3: 1988. (ii) Tank cover, sides and base (wind loading): BS6399, Part 2* *BS6399, Part 2 is to replace CP3; Chaper V: Part 2: 1972. DESIGN (i) Tank base: BS799, Part 5: 1987, type J tanks* *N/A for ring beam set in concrete base. (ii) Tank sides and cover: BS5950, Part 1: 1990 MATERIAL FINISH AND QUALITY (i) Welded structural steel: BS4360: 1990

BS5950, Part 2: 1992 Grade 43A. (ii) Protective coatinss: BS5493: 1977 (iii) Quality assurance: BS EN ISO 9001: 2000 Profile steel welded tanks are not designed as pressure vessels. They are designed to suit the hydrostatic pressure induced by the liquid being stored.

Braithwaite utilises state of the art CAD for design and detailing for optimum efficiency.

SURFACE PROTECTION Materials are delivered to site in accordance with a phased programme and prior to despatch they are blast cleaned to BS 4232 second quality and painted with a weldable holding primer to give a measure of protection during transit and erection. On completion of welding, the welds and all areas of abrasion and damage are flash blasted and patch primed before the application of paints selected to suit the tank contents and the external environment. For potable water tanks our standard WRAS approved site painting system is as follows. INTERNAL SURFACES Flash blast all welds and abraded areas of shop primer and patch prime, then apply one coat of Epigrip L425HS zinc phosphate primer, followed by one coat of Epigrip M344 P.W. epoxy finish (nominal dry film thickness: 250 microns). EXTERNAL SURFACES Flash blast all welds and abraded areas of shop primer and patch prime, then apply a two-coat system of Metanode chlorinated rubber paint (nominal dry film thickness: 250 microns). Drinking Water inspectorate approved linings can also be applied to the tank interior.

BITUMINOUS SAND Flat steel based tanks at ground level should be bedded on bituminous sand, provided by the contractor. It should be in accordance with BS2654, produced by hot mixing the following proportions by mass: (a) 9 ± 0.5% non-toxic cut back bitumen (i.e. fluxed with kerosene and not creosote) (b) 10 ± 1.0% filler: either limestone dust passing a sieve

on nominal aperture size 75 m complying with BS410, or Portland cement.

(c) 81 ± 1.5% clean dry washed sand with the properties given in table 2 of BS881, Part 2: 1973.

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TANK WITH RING BEAM SET IN CONCRETE BASEERECTION SEQUENCE OF A POTABLE WATER TANK FOR A WATER AUTHORITY

1. Base slab with ‘ring-beam’ in place. Waterproof membrane and reinforcing bars being positioned.

2. Surface concrete being poured, ‘ring-beam’ is cast in.

3. Sheets are delivered, first side erected and welded in place on ‘ring-beam’.

4. Tank walls and divided nearing completion. 5. First roof cover plate is positioned. 6. Tank completed, cleaned and primed. 7. Tank fully externally painted, inspection ladder

and guard railing fitted, plant room completed.

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TANK WITH FLAT STEEL BASE ON STEEL TOWER

EMERGENCY WATER TANK AT STEELWORKS

1. Tank being assembled on site at ground level. 2. Tank is hoisted into position. 3. Final precision positioning on tower. 4. Tank interior fully finished showing manway and

fixed access ladder.

Rest Platform

Gable Filling

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Peripheral Platform

Foundation Blocks (By others)

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SPECIFICATION, DESIGN & MATERIAL TANK BASE AND SIDES

The following illustrates the three alternatives methods of tank base and side construction: 1. FLAT STEEL BASE ON BITUMINOUS SANDTanks are usually installed on reinforced concrete slab covered with a smooth bitumen-sand mix that is at least 50mm thick. The bituminous sand ensures correct levelling and bedding down, and protects the underside of the base against corrosion. (See specification page 3). Flat base plates are overlapped and welded top side only. Profiled wall plates to the desired depth and 1.5 metres wide are welded to each other and to the base inside and out, forming a very rigid container. 2. RING-BEAM SET IN CONCRETE BASE For very large tanks it is often economically beneficial to eliminate the steel base and incorporate a ‘ring-beam’ into the reinforced concrete slab. Wall panels are welded directly to the beam. For the purposes of drainage it is sometimes desirable for the tank base to slope towards one end. In this situation a ‘ring-beam’ should be used. The slope can be incorporated in the concrete slab allowing the ‘ring-beam’ to be cast horizontally, thus simplifying fabrication and site erection. 3. FLAT STEEL BASE ON STEEL GRILLAGE

Tanks may be installed on steel grillage beams on bearer walls to allow access below the base or supported on tower bearers.

TANK COVERS Tanks can be provided with open top or with pitched covers. Where pitched covers are specified, construction is achieved by means of gable fillings fully welded to cover and walls.

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NOThsizTato AllwiTasuCom3

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TYPICAL TANK CAPACITY CHART

TE: ese capacities are for standard es. nk dimensions can be tailored clients requirements. capacities are shown nett thout freeboard. nk dimensions are to inside rfaces. nversions: to gallons: multiply by 220 to litres: multiply by 1000

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TYPICAL INSTALLATIONS

Tank fitted with access platform, external ladder and float level indicator.

Tank serving rural community installed in a remote location.

Dual compartment, dual height tank at water treatment works.

Shop fabricated tank for water treatment works.

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) 1633 262141 Facsimile: +44 (0) 1633 250631 E-mail: tanks@braithwaite.co.uk

Braithwaite Engineers Limited is a member of the ROWECORD GROUP