Fabrication.pdf

April 2, 2018 | Author: Lingka | Category: Structural Steel, Welding, Bending, Metal Fabrication, Building Information Modeling


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SteelConstruction.info The free encyclopedia for UK steel construction information Fabrication Fabrication is the process used to manufacture steelwork components that will, when assembled and joined, form a complete frame. The frame generally uses readily available standard sections that are purchased from the steelmaker or steel stockholder, together with such items as protective coatings and bolts from other specialist suppliers. Although a wide range of section shapes and sizes are produced, the designer may find that the required section size is not available. In this case, built-up girders may be fabricated from plate. Sections and plate girders may also be strengthened by stiffening the web or flanges depending upon the load to be carried. Most modern steelwork fabrication factories have computer aided design and detailing (CAD) which is linked directly to factory floor computer numerically controlled (CNC) machinery creating a genuine CAD/CAM environment. The accuracy of the computer generated details being transmitted directly to the computer aided manufacturing (CAM) machinery increases the quality standards of production The fact that machinery has taken over from the tape measure means that the frame is produced to high quality standards which are reflected in the speed and accuracy of steel erection on site. This results in significant benefits both to the client and main contractor. CAD/CAM machinery (Image courtesy of Paddy Wall & Sons) Design for economic fabrication There are a number of general "technical" factors to consider in terms of design for economic fabrication that apply to most building projects. Some relate to the complexity of the particular project, whilst others are specific to the type of project, e.g. multi-storey, portals, trusses. Specification 1 / 27 //www.steelconstruction.info/Fabrication - 16th September 2017 SteelConstruction.info The free encyclopedia for UK steel construction information Conformance with the National Structural Steelwork Specification for Building Construction (NSSS) will reduce uncertainty. Additional project specific clauses, more demanding tolerances, and additional testing will increase costs. Bay size Diagonal steel bracing – Silverstone (Image courtesy of Kingspan Structural Products) Structural steelwork prices are influenced by the size of each individual piece (i.e. number of pieces per tonne), which is largely dependent on bay size. Consider larger bay sizes, where the extra weight due to longer spans may be totally offset by the reduced price per tonne and the saving in number of columns and related workmanship. Also the resultant column-free space generally adds value to a project. Structural steel frames must have the required degree of lateral resistance to wind loads. This can be provided by a stiff core or by the frame itself - diagonal steel bracing is usually a less expensive solution than moment frames. Complexity Modern CNC fabrication equipment can cope with complex individualistic designs but, in general, the more complex the fabrication the greater the cost. Fabrication is more economic with: Single square end cuts One hole diameter on any one piece avoids drill bit changes 2 / 27 //www.steelconstruction.info/Fabrication - 16th September 2017 Complex individualistic designs are going to cost more per tonne. lead times and factory handling. M20 grade 8. Rationalise the range and tonnages of section sizes used.16th September 2017 . Tubular steelwork at the National Football Centre (Image courtesy of Billington Structures Ltd. in which case S275 should be used.info/Fabrication . leave the choice of the connection detail to the steelwork contractor as the type and design of connections directly influences the total frame cost. even with modern CNC equipment. e.) 3 / 27 //www.SteelConstruction.g.8 for shear connections Wherever possible.keep it simple! Materials Avoid mixing steel grades where possible and rationalise the range of section sizes / tonnages used in order to minimise cost.info The free encyclopedia for UK steel construction information Holes in flanges and webs aligned where possible Web holes having adequate flange clearance Rationalised range of fittings for connections The use of a small range of standard bolts. If you wish to keep costs down .steelconstruction. In general steel grade S355 offers greater economy unless stiffness / deflection governs the design. Further guidance on the design of buildings for economic fabrication is available in: BCSA publication Steel Buildings.Fabrication SCI publication P150 Design for Manufacture Guidelines Guidance on the design for economic fabrication of bridges is available in BCSA publication Steel Bridges. welding consumables. Sections and plates 4 / 27 //www. Chapter 7 - Costs.16th September 2017 . for computer controlled machinery). Where the steelwork is pre-designed. Guidance on identifying the requirements for the production and exchange of accurate.g. while tubular sections are a possible alternative for columns and long span trusses.) and software (e. light gauge decking and corrosion protection and fire protection systems are all manufactured to European standards and in many cases are CE marked. Quality of engineering and documentation Completeness and accuracy of information are vital for a steelwork contractor to be able to properly assess the work involved. drilling.Fabrication The Steel Designer’s Manual. Asymmetric beams are often used to reduce the construction depth of floor systems. stiffeners and base plates and can be used to fabricate economic ‘I’ sections for longer spans. timely and detailed information for projects involving steelwork is available in BCSA publication no. Grinding of welds to improve the appearance of the steel is usually only required for exposed steel in close proximity to a building’s occupants. Chapter 33 .info The free encyclopedia for UK steel construction information Ensure that the most appropriate sections are specified for the particular application. often with an “aesthetic bonus”.g. Steel plate is used to fabricate connections. welding machines etc. structural bolts. 45/07. Chapter 11 .info/Fabrication . cutting. sawing.SteelConstruction. Architectural influence Ensure that unnecessary finishing is not specified and that any applied corrosion resistant coating is appropriate for the environmental conditions to be encountered. Materials and components Steel sections and plate. While tubular sections have a higher first cost than “I” sections. ensure that all member sizes are shown and that the connection forces are shown or are available. In addition to these materials steel fabrication also needs fabrication equipment (e. their lower overall gross weight required to perform the same function can largely offset this.steelconstruction. “I” sections are usually most economical in conventional framing. BS EN 10210-1[2] for hot- finished tubes. Bolts Although the majority of structural bolts are manufactured outside of the European community they are all CE marked and manufactured to European standards – BS EN 14399[5] for preloaded bolts and BS EN 15048-1[6] for non-preloaded bolts.info/Fabrication . cladding and roofing systems are also available and can provide novel and cost effective alternative solutions. Steel stockholders play a vital part in the steel construction supply chain.SteelConstruction. cladding materials.1. fasteners.16th September 2017 . flats. light sections.) Steel sections and plates are generally manufactured to BS EN 10025-2[1] for open sections. The specification and quality controls placed on stockholders by the BCSA ‘Model Specification for the Purchase of Steel Sections and Plates’ ensures the quality of steel sections and plate placed on the UK market by BCSA stockholders. The stockholders provide a range of products to the construction industry including heavy structural sections. Many of these are manufactured to either European product standard or European Technical Approvals. The industry has an extensive network of depots serving all parts of the country. angles. plates. product specific CE Inspection documents. Proprietary products Proprietary products such as some cellular beams. purlins. All BCSA stockholder members have quality management systems such as BS EN ISO 9001[4] in place supplemented by individual identification systems to ensure full traceability from the steel manufacturer to the steelwork contractor.steelconstruction. The exacting quality control requirements placed on European manufacturers and distributors by the BCSA ‘Model Specification for the Purchase of Structural Bolting Assemblies and Holding Down Bolts’ ensures the quality of structural bolts placed on the UK market by BCSA bolt distributors. Large orders can be supplied direct from the steel mills. ensuring that the market is supplied with what it needs when it is needed. Total stocks held represent about 40 days supply. and BS EN 10219-1[3] for cold-formed hollow sections. 5 / 27 //www.info The free encyclopedia for UK steel construction information A stockholder’s external facility (Image courtesy of Rainham Steel Company Ltd. All sections are accompanied by Type 3. but Steelwork Contractors normally obtain their steel sections and plates from a steel stockholder. steelconstruction. Cold-formed sections 6 / 27 //www.SteelConstruction.info The free encyclopedia for UK steel construction information (Images courtesy of Kloeckner Westok) Coating systems Paint systems. galvanizing and other protective coatings have developed over the years in response to numerous technological advancements that have brought improved performance and comply with industrial environmental legislation.16th September 2017 . Manufacturers are conscious of their position in the supply chain and the demands by industry for best service.info/Fabrication . SteelConstruction. sate-of-the-art CNC machinery has been made available from international manufacturers that have helped the UK’s steel construction sector improve productivity to become the envy of the world. 7 / 27 //www. Fabrication processes Fully automated saw / drill line (Image courtesy of Parker Steel) Advances in quality and productivity in the steel construction sector are largely due to developments in fabricating machinery. side rails.16th September 2017 .info The free encyclopedia for UK steel construction information Purlins and side rails on a portal frame (Image courtesy of Caunton Engineering Ltd.info/Fabrication . these products are ideally suited for most commercial and industrial applications. while a number of them have been specifically designed for refurbishment applications. channels systems or floor decking systems. Thanks to this continuous improvement.) Lightweight cold formed steel products are vital components for the majority of steel construction projects.steelconstruction. Whether it is purlins. walling. The manufacturers of steelwork fabrication equipment have invested heavily in research and development to produce the technological advances required by today’s steel construction sector. immediately after blast cleaning. which is essential to provide a suitably clean finish for welding and subsequently also to produce a keyed surface ready to accept paint. that is only enough to keep the fabrication lines supplied for a few weeks. The force of the shot against the surface displaces dirt and scale. Fabrication is a rapid process. Shot blasting Cutting & drilling In the fabrication factory one of the first operations is to cut the sections to length and profile the plates to the desired size or shape. although some chose to carry out the shot blasting after the sections are cut to length.16th September 2017 . approx. Prefabrication primers can be applied.SteelConstruction.steelconstruction. This surface preparation is an important part of the fabrication process. to maintain the reactive blast cleaned surface in a rust free condition through the fabrication process until final painting can be undertaken. Here it is unloaded and stored prior to being moved to the fabrication lines for processing. This can be done in a number of ways using a range of automated machinery: Circular saws Circular saw (Image courtesy of Kiernan Structural Steel Ltd. and also indents the steel creating a "rough" surface.info/Fabrication . When paint is sprayed onto this clean abraded surface it adheres well and provides a longer life for the paint system. Shot is fired at the steel. or steel stockyard.) 8 / 27 //www. 70 microns deep. The stockyard Shot blasting For many Steelwork Contractors. and whilst a typical stockyard may contain several thousand tonnes of material. sections and plates are shot blasted prior to fabrication.info The free encyclopedia for UK steel construction information Preparation Stockyard The steel fabrication story begins as the basic sections and plates are delivered to a storage area. copper nozzle constricts the arc between the electrode and the work piece. This process uses a mixture of oxygen and a fuel gas (propane) to preheat the metal to its 'ignition' temperature. Sections are delivered from the stockyard to the machine bed of the saw. which. Pre-programming the saw not only ensures that steel is accurately measured and cut to the length required but the operation is carried out at the most efficient speed for the cutting operation.) Gas or flame cutting systems are also used to cut components from steel plate.info/Fabrication . Plasma cutting Drilling and punching 9 / 27 //www.steelconstruction. A fine bore. the plasma gas flow is increased so that the deeply penetrating plasma jet cuts through material whilst molten material is removed in the efflux plasma. for steel. Flame cutting Plasma cutting Components can also be cut efficiently by plasma arc systems.000°C and the velocity can approach the speed of sound. This increases the temperature and velocity of the plasma emanating from the nozzle. The oxygen jet blows away the slag enabling the jet to pierce and continue to cut through the material.SteelConstruction. so reducing wear on the blade. The temperature of the plasma is in excess of 20. is 700°C .info The free encyclopedia for UK steel construction information Circular Saws are used for cutting to length. Saw cutting Gas or flame cutting Flame cutting (Image courtesy of Kiernan Structural Steel Ltd.900°C (at this temperature a bright red heat) but this is still well below the material’s melting point.16th September 2017 . A jet of pure oxygen is then directed into the preheated area instigating a vigorous exothermic chemical reaction between the oxygen and the metal to form iron oxide or slag. When used for cutting. accurately sized. Where fatigue is an issue the holes are punched 2mm undersized and reamed to the correct diameter. the steel will be sent to a specialist fabricator. In the punching process a cutting punch is forced under pressure through the steel into a die below. For drilling. so producing a clean. Drilling and punching Bending Where feature steelwork or curved structural steelwork is required.16th September 2017 .info/Fabrication . Curved steelwork at Hayes Garden Centre 10 / 27 //www.steelconstruction.SteelConstruction. all holes are pre drilled or punched in the fabrication factory. which run up the side of the bit. curves and bends can be created. high speed steel twist bits are used. which covers the theory and also gives examples of curved steel in buildings. hole. Design considerations relating to the use of curved members are explained in the Design of Curved Steel (P281). Here through the use of roller bending or press braking equipment. The rotating bit cuts through the steel and the metal being removed during the process forms swarf (the curls of metal that spiral off during machining). The swarf travels up the flutes (the helical grooves). Punching can be used where the thickness of the metal is less than the diameter of the hole or in the case of a non- circular hole its minimum dimension (Note that the 15mm thickness limit for punching mentioned in the video clip below no longer applies). Further information can be sourced from well known bending companies.info The free encyclopedia for UK steel construction information Drilling machine To allow sections to be rapidly bolted together on site. Plate bending Tube bending Tube bending is carried out in a similar way to section bending. Tube bending Press breaking 11 / 27 //www. Generally. This is used to maintain the cross section of the web during bending Section bending Plate bending Plate bending is similar to section bending but the bending rolls are horizontal and are longer. This process involves progressive bending of a section through a set of bending rolls that are shaped to the cross section of the bar.16th September 2017 . On each pass through the rolls. Pulling units are used on most beam sections curved on the x-x axis (the strong way). a tube is stronger than its equivalent size beam so.) Steel can be curved by roller or section bending. to bend it.info/Fabrication . more bend is created and the process is repeated until the desired curvature is achieved. more force is required.info The free encyclopedia for UK steel construction information (Image courtesy of Kloeckner Westok) Section bending Section bending (Image courtesy of Barnshaw Section Benders Ltd.steelconstruction. more curvature is introduced and the process is repeated until the desired curvature is achieved.SteelConstruction. During bending the outer profile of the tube is supported by sets of machined rolls. Plate is fed in flat and on each pass through the rolls. To achieve this a ‘Press Breaking’ process is used to press the steel along its entire length. Manual Metal Arc welding (MMA) 12 / 27 //www.steelconstruction. Different welding techniques are used for different activities within the fabrication factory. it is used to prepare joints for connection on site and for the attachment of other fixtures and fittings. Essentially. Tee splitting Profiling of tubular sections In addition to the standard fabrication processes common to all structural elements. off-centre or the flanges can be trimmed. the welding process uses an electric arc to generate heat to melt the parent material in the joint. this is due to the stress being released after the cut. by covering the pool with an inert slag or a combination of both actions.SteelConstruction. The Tee section needs to be straightened after splitting. tubular sections may require profile-shaping or saddling. Sometimes these shapes are required at 12metres long (or more).info The free encyclopedia for UK steel construction information A wide variety of shapes can be formed from profile cut or sheared plates. the weld pool solidifies fusing the parent and weld metal together. Protection is achieved either by using an inert shielding gas. A separate filler material supplied as a consumable electrode also melts and combines with the parent material to form a molten weld pool. This type of connection can be most commonly seen on tubular trusses Profiling tubes Welding Main article: Welding Welding is a core activity in the fabrication factory. Press breaking Tee splitting Flame cutting is used to make tee sections from beams. This involves the use of a burning torch on a trolley arrangement that runs up the beam until the cut is completed. The beam can be cut centrally. BS EN 1090-2[9]. The weld pool is susceptible to atmospheric contamination and therefore needs protecting during the critical liquid to solid freezing phase. Profile-shaping is required where the end of a tubular section has to fit the contour of a curved surface on a circular hollow section main member.info/Fabrication . Several passes or runs may be required to fill the joint or to build up the weld to the design size Assembly and welding requires skilful operatives and will generally be the largest element of the fabrication costs. Welding requires the steelwork contractor to have in place a welding quality management system to BS EN ISO 3834[7] under the control of a Responsible Welding Coordinator. CE marking of fabricated steelwork to BS EN 1090-1[8] requires the steelwork contractor to have in place a certified Factory Production Control system in line with BS EN 1090-1[8] which is supported by the European standard for Execution of steelwork. As welding progresses along the joint.16th September 2017 . This shields the molten puddle from the atmosphere. hence its name .) Metal Active Gas (MAG) is used for continuous welding. Shielded metal arc welding employs a "Stick" type electrode covered with a flux coating. Manual Metal Arc welding (MMA) Metal Active Gas welding (MAG) MAG Welding (Image courtesy of Kiernan Structural Steel Ltd. This is supplied by a power source and fed through a "Gun" by a roller wire-feeder. MAG welding employs a continuous solid wire electrode carrying current.steelconstruction.info The free encyclopedia for UK steel construction information MMA or ‘Shielded metal arc’ welding is used to temporarily join or tack weld components during fabrication prior to full strength welding. Metal Active Gas welding (MAG) Submerged Arc Welding (SAW) 13 / 27 //www. The molten weld pool is protected from atmospheric oxidation by a gas shield (formed from an Argon and Carbon Dioxide mixture). An arc is struck between the continuous metal electrode and the steel work piece – this effectively melts the two together. The electrode is brought into contact with the work piece and an electric arc between the electrode tip and the work piece is struck.info/Fabrication . The flux coating on the welding rod is heated to a gas and liquid.SteelConstruction.16th September 2017 .Shielded metal arc welding. info The free encyclopedia for UK steel construction information Minimal PPE required for SAW welding (Image courtesy of Mabey Bridge Ltd. Submerged Arc Welding (SAW) Non Destructive Testing (NDT) Non destructive testing is carried out to ensure that welds are free from unacceptable defects such as cracks and inclusions.SteelConstruction. The arc is "Submerged" under the powder.info/Fabrication . The arc is struck when the wire electrode contacts the work piece. MPI utilises a magnet and a magnetic liquid on the surface of the weld. and ultrasonic testing. formed by the action of the arc on a powder covering the whole weld reaction area. and ultrasonic testing involves sending sound waves through the weld and interpreting the resulting echo pattern on an oscilloscope Non Destructive Testing (NDT) Coating 14 / 27 //www. Protection of the weld is provided by slag.16th September 2017 .) For welding long pieces of steel together to fabricate structural sections. The main NDT techniques are magnetic particle inspection (MPI). This is generally much larger diameter than in MAG welding. In Submerged arc welding a power current is applied to a continuous wire electrode. submerged arc welding is used.steelconstruction. info The free encyclopedia for UK steel construction information Coating application in the fabrication factory (Image courtesy of Hempel UK Ltd. Access for painting is difficult for double angle or double channel members and these types of elements have now been largely superseded by using Square Hollow Section (SHS) / Rectangular Hollow Sections (RHS) members that reduce the painted area and provide fewer locations for corrosion traps to form. and fire resistance in the case of intumescent coatings.) The application of paint coatings or hot dip galvanizing to the steelwork is carried out (if required) at the end of the fabrication process. In such cases.info/Fabrication . Larger components would have to be manually blasted. the emphasis for buildings is on simple systems that are easy to apply involving spray application after automatic blasting. Coating application Generally.16th September 2017 . and components that are not too bulky can be re-blasted by passing them through the automatic blasting machine on a conveyor. In addition to adding any aesthetic finish specified by architects. the weld areas would require further surface preparation before coating. Paint coating systems are generally applied in the fabrication factory to reduce site activity times and make significant cost savings. Accuracy 15 / 27 //www. coatings are also widely used to provide corrosion protection. Many fabrication facilities have internal atmospheres that enable the steel to be blast cleaned before fabrication and surface coated afterwards.SteelConstruction. it makes economic sense to keep some components with no welding as these would not require re- blasting before coating application. To minimize this double handling.steelconstruction. for it involves structural steelwork manufactured remote from the site.16th September 2017 .steelconstruction.) The means of handling and manipulating steelwork within a Steelwork Contractors factory has developed over time to suit their particular operations. the need for trial erection has been much reduced. with the much-improved accuracy achieved by automated fabrication procedures. Guide to Work at Height during the Loading and Unloading of Steelwork There are three regimes for the transportation of steelwork on the UK road network: Normal loads 16 / 27 //www. civil engineering works at the site. or crane girders attached to the steel frame of the fabrication factory. High temperature processes are used to make the steel products. BCSA have published several health & safety guides to assist steelwork contractors with the handling and transportation of steelwork. including: Health and Safety in the Workshop for Employees: A Guide for Steelwork Contractors. Steel elements may be picked up using chains or strops. so reducing the risk of delays in erection or damage to protective treatment. so dimensional variation resulting from distortion is inherent and unavoidable. such as those defined in the NSSS. trial erection can be carried out to ensuring that fit-up and geometry can be achieved at site. However. A thorough understanding of the causes of fabrication distortion. it generally involves the use of computer controlled conveyor systems and overhead gantry cranes running on either rails on the floor. to form the components and to join them together. These interface with each other and yet their precision varies from the high accuracy of mechanical components to the approximation inherent in placing concrete. Handling and transportation Handling steelwork in the factory (Image courtesy of Mabey Bridge Ltd. or temporary lifting brackets can be welded on to facilitate the use of hooks.SteelConstruction. However. the steelwork contractor will assess the design to determine how best to undertake the fabrication to control dimensions and achieve the required accuracy of steel fabrication to ensure proper fit-up and assembly at site. For each new project. For particularly complex fabrications.info The free encyclopedia for UK steel construction information Modern steel fabrication involves the manufacture of large and often complex welded assemblies of rolled steel products. Dimensional variation is significant in a number of ways. and sometimes even precise mechanical components.info/Fabrication . and experience in the control and correction of distortion allows the Steelwork Contractor to work within standard fabrication tolerances. (Authorisation of Special Types) (General) Order”. Each police authority on the planned route has to be notified at least 2 days in advance. rigid vehicle length is usually the girder length. There are three categories of STGO vehicles. except where the route includes an underbridge with weight restriction or an over-bridge with height restriction. Where the police do insist on escorting loads.SteelConstruction. entitled “Road Vehicles. and overall height less than 4. the trailer bed is usually about 1. which may have implications in the timing of critical lifts.25m for the load above. The letters STGO.95 m. the notification / escort arrangements must be separately agreed with every police force en route. Even with wide loads the number of times the police insist on escorting them has reduced since the Department of Transport introduced the 'Code of Practice: Lighting and Marking for Abnormal Load Self escorting vehicles incorporating Operating guidance’[11].5 tonnes. In the case of transportation of bridge girders. are an abbreviation for this section of the Act. gross weight less than 44 tonnes. which are displayed on the tractor unit of most abnormal loads.9 m. Some forces also have restrictions on the timing of escorted loads.steelconstruction. The latest Order is SI 2003 No. with no axle weight over 11. Although the height limit is 4.) Certain vehicles that exceed the above ‘normal’ limits are covered by a section of the Road Traffic Act 1988. Abnormal loads Transporting steelwork by road (Image Courtesy of Mabey Bridge Ltd. Often the police will not insist on escorting loads that are long and not wide as these cause far fewer manoeuvrability problems.1998[10]. width less than 2.info/Fabrication .info The free encyclopedia for UK steel construction information Abnormal loads Special order Normal loads Vehicles with rigid vehicle length less than 18. but all three have a maximum vehicle length of 30m and width of 5m.65 m. It is not unknown to be taken so far by one force then held for hours if the next force has an emergency that intervenes.7 m high so that leaves only 3. so delivery from works to site can be unpredictable.16th September 2017 . Special order 17 / 27 //www. and it is also necessary to notify bridge owners on the route if the weight exceeds 44 tonnes. each with different weight limits.95 m can travel anywhere at any time. 16th September 2017 . However.SteelConstruction.info/Fabrication . Special Orders are usually valid for 6 months.06 Specification National Structural Steelwork Specification (6th Edition) 18 / 27 //www. At least three months should be allowed between the first application for such a permit or order and the anticipated date of the actual movement. but approval must be gained from the Highways Agency (or the Scottish Executive or Welsh Assembly Government) in the form of a VR1 Permit or a Special Order. and preferably limit the length and width of elements such that they comply with the ‘normal load’ rules. Clearly it is advantageous for designers to consider transportation when determining element sizes.info The free encyclopedia for UK steel construction information If the vehicle and load to be moved fall outside the STGO categories it is still possible to move. All details of the load must then be notified to the Highways Agency. and specialist bridgeworks fabricators are experienced in the movement of very long girders using ‘special orders’. together with precise dispatch and delivery points.steelconstruction. Further guidance on the transport of steelwork by road is available in GN 7. transportation of larger fabrications is commonplace under the ‘abnormal load’ rules. A Special Order details the approved route and must be followed exactly. The specified notice must be given to each police region for the actual movement and to the relevant bridge owners on the route. requiring unnecessary quality and excessively tight tolerances will lead to higher costs. where standards allow options and alternatives. technical. and health & safety resources as well as track record and employed personnel.SteelConstruction.16th September 2017 .steelconstruction. and helps the client to fulfill the regulatory duty only to use competent contractors. For this purpose two checklists of competences are available: Normal scope of competence for activities that steelwork contractors should be competent to undertake with their own personnel Special scope of competence for activities that steelwork contractors should be able to manage using specialist subcontractors as necessary Having checked at tender stage what a project demands. which additional requirements apply. such as the National Structural Steelwork Specification. The project specification should also avoid over-specification . The assessments are carried out annually with a physical factory inspection every three years. Failure in clarity will lead to extra provisions for risk and extra costs in resolving queries. Each company only qualifies for inclusion on the lists after being assessed by specialists who check financial. steelwork contractors should warn their clients if they are unable to undertake any of the normal activities. The result is three criteria: Categorisation of the company in terms of the work it can execute technically Classification of the company in terms of the maximum size of contract it should handle Safety Schemes in Procurement (SSIP) minimum health and safety criteria The assessments provide clients with an easy way to pre-qualify steelwork contractors for buildings and bridges before contracts are tendered. Thus. and their clients should check beforehand whether a steelwork contractor is willing to undertake any of the special activities.info/Fabrication . equipment and finance at their disposal.info The free encyclopedia for UK steel construction information It is important that the steelwork specification (and accompanying drawings) for a project should express clearly the particular requirements for a structure and. This ensures that the successful steelwork contractor has the special skills to suit the project. The project specification should generally follow recognized industry standards. the following: BCSA membership assessment requirements Register of Qualified Steelwork Contractors for Bridgeworks (RQSC) Steel Construction Certification Scheme (SCCS) CE Marking Steel Construction Sustainability Charter (SCSC) Steel Construction Building Information Modelling (BIM) Charter BCSA Steelwork Contractor membership The BCSA membership assessment and RQSC for Bridgeworks requirements are more than just registers of companies selected from a tick list. 19 / 27 //www. manpower. Quality management The steel construction industry and supply chain are able to call upon members of the BCSA and their inherent qualities of competency and professionalism. the first priority for competent contractors is to ensure that the scope of work can be safely undertaken with the resources of know-how. and the Specification for Highway Works[12]. all demonstrated by among other things. The categories of work are general and the precise scope of work demanded by each project will differ. info The free encyclopedia for UK steel construction information The BCSA membership assessment also include the stage 1 health and safety assessment and gives members mutual recognition of the Safety Schemes in Procurement (SSiP). Quality Management System Certification (QM) Quality management systems operated by the certified contractors are formally assessed to ensure compliance with the requirements of BS EN ISO 9001[4].SteelConstruction. Each certificate is valid for three years during which period SCCS conducts interim surveillance audits to monitor continued compliance with the certified management system. SCCS has developed additional certification and monitoring services for the steelwork contractors with integrated or separate Environmental and Health & Safety management systems.org/directories Steel Construction Certification Scheme The Steel Construction Certification Scheme (SCCS) is a wholly owned subsidiary of The BCSA and provides a Quality Management Systems certification service for steelwork contracting organisations. Highways England includes in its Specification for Highway Works[12] a requirement that only firms listed on the Register of Qualified Steelwork Contractors for Bridgeworks (RQSC) for the type and value of work to be undertaken will be employed for the fabrication and erection of bridgeworks. A separate Register operates to cover bridgeworks.steelconstruction. Steelwork contractors can be sourced according to the required project Class and Category on www. Each certificate is valid for three years during which period SCCS conducts interim surveillance audits to monitor continued compliance with the certified management system. CE Marking and Factory Production Control (FPC) 20 / 27 //www. Occupational Health and Safety Management System Certification (HSM) Occupational health & safety management systems operated by the certified contractors are formally assessed to ensure compliance with the requirements of BS OHSAS 18001[14].steelconstruction. Each certificate is valid for three years during which period SCCS conducts interim surveillance audits to monitor continued compliance with the certified management system.16th September 2017 . Environmental Management System Certification (EM) Environmental management systems operated by the certified contractors are formally assessed to ensure compliance with the requirements of BS EN ISO 14001[13].info/Fabrication . steelconstruction. and is legal requirement of the Construction Products Regulation[15]. National Highway Sector Schemes (NHSS) SCCS has been accredited by UKAS to carry out assessments against: NHSS 3 [17] – The stocking and distribution activities for mechanical fasteners NHSS 19A[18] – For corrosion protection of ferrous materials by industrial coatings NHSS 20[19] – The execution of steelwork in transportation infrastructure assets Each certificate is valid for three years during which period SCCS conducts interim surveillance audits to monitor continued compliance with the certified NHSS.info/Fabrication . Steel Construction Sustainability Charter 21 / 27 //www.16th September 2017 . bolting and welding systems to enable companies to carry out CE marking. FPC systems operated by the certified steelwork contractors are formally assessed to ensure compliance with the requirements of: BS EN 1090-1[8] for structural steel BS EN 14399-1[16] for high strength structural bolting assemblies BS EN 15048-1[6] for non-preloaded structural bolting assemblies Each certificate is valid for three years during which period SCCS conducts interim surveillance audits to monitor continued compliance with the certified FPC system.info The free encyclopedia for UK steel construction information CE marking is an audited and tested declaration that a product meets specific public safety requirements and specifications throughout the supply chain.SteelConstruction. SCCS provide certification of factory production control. systems and procedures to achieve ‘Level 2 BIM’ maturity as defined by PAS 1192-2[21].info The free encyclopedia for UK steel construction information The objective of the Sustainability Charter (SCSC) is to develop steel as a sustainable form of construction in terms of economic viability. Member. and specifically that: The company has the capability of working within a project using a ‘Common Data Environment’ as described in PAS 1192-2[21].steelconstruction.info/Fabrication . Silver and Gold. the steel construction supply chain also to implement. promoting respect for people and communities associated with steel construction. Benchmarking key performance indicators (KPIs) are being developed by the BCSA. and can now be certified against the requirements of both PAS 91[20] and PAS 1192-2[21] as outlined below. The company has arrangements for training employees in BIM related skills and assessment of their capabilities. the status achieved depends on the number of points scored following audit. Steel Construction Building Information Modelling (BIM) Charter BIM model (Image courtesy of S.SteelConstruction. operating in a healthy. The company has a documented policy.) The UK Government’s requirement for Level 2 BIM on all central government projects means the construction industry wants to know which suppliers are BIM compliant. promoting resource and energy efficiency in steel construction through reuse and multi cycling. social progress and environmental responsibility. 22 / 27 //www. implementing sustainable development by constructive dialogue and enhancing knowledge of sustainability to share with and promote others in. having high ethical standards. BCSA has three levels of status in the Charter i. Compliance with PAS 91[20] section 4. not only to measure the progress of sustainable development in steel construction but to demonstrate genuine commitment. BCSA steelwork contractors are now able to demonstrate compliance with Level 2 Building Information Modelling (BIM) with the launch of the Steel Construction BIM Charter.2 table 8.e. The company has the capability of developing and delivering or working to (depending upon the role(s)) a BIM Execution Plan (BEP) as described in PAS 1192-2[21].Structures Ltd.16th September 2017 . BCSA requires Charter Members to formally declare to operate in sustainable ways that work towards: adding value to clients and stakeholders. safe and environmentally sound manner.H. optimising the eco-efficiency of steel construction life cycle. On construction sites the equipment (often temporary) has to be brought to the final position of the item and then moved each time. This also gives additional advantage for longer hours of production including night shift work if necessary. These processes also reduce the risk of error and the need for re work to take place on site where even minor alterations may need lots of additional access or plant and equipment to be mobilized. 23 / 27 //www. The use of automated and semi-automated multi-function machines that cut.4 Suppler BIM assessment form 6. The BCSA’s online directories mean clients and main contractors can see which companies have been assessed against the BIM Charter.SteelConstruction. drill and mark the steelwork reduces the number of people involved in the process and the need to handle the steel i. which is then followed up by an onsite audit.info The free encyclopedia for UK steel construction information Compliance with the supply chain assessment requirements outlined in PAS 1192-2[21] and specifically defined in sections: 6.info/Fabrication .e.16th September 2017 . Generally the fabricated item moves through the production area until completed and then stored. Health and safety Automated sawing & drilling machine Working on construction sites means that lots of people and equipment have to be provided with temporary access especially for working at height. turning and repositioning is reduced. all of this in a controlled environment with no disruption to the local communities. Certified companies are provided with a comprehensive document summarising the company’s BIM capability. Working within a factory eliminates any health and safety issues concerned with adverse weather conditions and production can continue.steelconstruction. which they can then provide to the supply chain.6 Supplier resource assessment form The certification process requires companies to carry out an online assessment. with the Charter providing a simple way to prequalify steelwork contractors as BIM compliant. The steelwork is pre fabricated in factories which significantly reduces the on site work especially the work at height as the steel components only need to be assembled.5 Supplier information technology (IT) assessment form 6. all of which increases risk of incidents as lots more moving and repositioning needs to take place. This reduces site storage and minimizes lifting and handling where most risks of incidents and injuries can be presented.steelconstruction.16th September 2017 .info/Fabrication . 24 / 27 //www. this enables the deliveries to site to be managed in such a way that offloading can be direct to the final position. Loading and unloading of steelwork is carried out in designated areas with the appropriate access and lifting equipment. The systems used to programme the production of fabricated steelwork mean that the work can be packaged.info The free encyclopedia for UK steel construction information Pedestrian access and egress is controlled by permanent marked routes which are separate from the vehicular routes.SteelConstruction. info/Fabrication . General requirements. 20. TSO 13. BSI 2. High-strength structural bolting assemblies for preloading (Various Parts). International Organization for Standardization 5. Statutory Instruments 2003 No. BSI Resources National Structural Steelwork Specification (6th Edition).04. UKAS.18. ↑ Code of Practice Lighting and Marking for Abnormal Load Self escorting vehicles incorporating Operating guidance. Execution of steel structures and aluminium structures. Highways England 12. For corrosion protection of ferrous materials by industrial coatings. ↑ 6. Requirements for conformity assessment of structural components. ↑ 8. BSI 14. Non-preloaded structural bolting assemblies. Volume 1: Specification for Highway Works. BSI 15. ↑ 12. ↑ Construction Products Regulation (EU) No. ↑ BS EN 10025-2:2004. Official Journal of the European Union L88/5 4. BSI 4. The Execution of Steelwork in Transportation Infrastructure Assets. BCSA Chapter 9: Welding 25 / 27 //www. BSI 21. ↑ BS EN 14399-1:2015. August 2014. ↑ Road Vehicles (Authorisation of Special Types) (General) Order. ↑ BS EN 1090-2:2008+A1:2011. Hot finished structural hollow sections of non-alloy and fine grain steels. ↑ NHSS 3: National Highways Sector Schemes for Quality Management in Highway Works. The Stationery Office Limited 11. (Publication No. BSI 10. BSI 8.steelconstruction. June 2017 19. 19A. Series 1800 Structural Steelwork. 57/17. ↑ BS EN 10210-1:2006. Execution of steel structures and aluminium structures.16th September 2017 . BSI 9. Issue 2 (9001:2015).4 PAS 1192-2:2013 Specification for information management for the capital/delivery phase of construction projects using building information modelling. 305/2011 of the European Parliament and of the Council of 9 March 2011. BCSA 2017 Steel Buildings. Issue 3 (9001:2015). July 2016 18. High-strength structural bolting assemblies for preloading. Requirements. ↑ BS EN ISO 3834:2005. 2003. BSI 7. ↑ BS EN 14399-1:2015. UKAS.020.info The free encyclopedia for UK steel construction information References 1.012. Cold formed welded structural hollow sections of non-alloy and fine grain steels. ↑ BS OHSAS 18001:2007. Quality requirements for fusion welding of metallic materials (Various Parts). Occupational health and safety management systems. 3.1 BS EN 15048-1:2016. Technical requirements for steel structures. ↑ BS EN 10219-1:2006. BSI 17. ↑ 20.08. 2016.2 BS EN 1090-1:2009+A1:2011. The Stocking and Distribution Activities for Mechanical Fasteners.321.121. December 2016 20. ↑ 4.4. (Publications Code PR152/15 ). General requirements. Hot rolled products of structural steels.021.1 PAS 91:2013 Construction prequalification questionnaires. ↑ BS EN ISO 14001:2015 Environmental management systems . BSI 6. Technical delivery requirements. ↑ NHSS 19A: National Highways Sector Schemes for Quality Management in Highway Works. ↑ NHSS 20: National Highways Sector Schemes for Quality Management in Highway Works. Issue 1 (9001:2015).2011 16. Technical delivery requirements. ↑ 21.221. Publication No.1 Manual of Contract Documents for Highway Works (MCHW). Technical delivery conditions for non-alloy structural steels. 35/03). 2003.1 BS EN ISO 9001:2015. UKAS.06.SteelConstruction.Requirements with guidance for use. 1998. Quality management systems – Requirements. BSI 3. (P185).04 Plate bending Guidance Note 5.09 The prefabrication meeting Guidance Note 6. 2007.07 Straightening and flattening Guidance Note 5. BCSA Model Specification for the Purchase of Structural Bolting Assemblies and Holding Down Bolts. D.06 Visual inspection after welding Guidance Note 7. BCSA Special scope of competence. BCSA Health and Safety in the Workshop for Employees: A Guide for Steelwork Contractors.06 Thermal cutting of structural steels Guidance Note 5..03 Geometrical tolerances Guidance Note 5.04 Hydrogen / HAZ cracking and solidification cracking in welds Guidance Note 6.01 Weld preparation Guidance Note 5.steelconstruction. 49/09). (Publication no.16th September 2017 . (Publication no. 1995. BCSA Chapter 4 Bolting Chapter 5 Welding Chapter 6 Accuracy Chapter 7 Costs Allocation of Design Responsibilities in Constructional Steelwork.C.info The free encyclopedia for UK steel construction information Chapter 10: Bolting Chapter 11: Fabrication Chapter 15: Specification and Quality Design for Manufacture Guidelines (P150). 45/07). 2011. BCSA Design of curved steel (P281). (Publication no. BCSA Guide to Work at Height during the Loading and Unloading of Steelwork. BCSA Normal scope of competence.02 Post-weld dressing Guidance Note 5.03 Sub-surface inspection of welds Guidance Note 6.01 Control of weld quality and inspection Guidance Note 6. BCSA Model Specification for the Purchase of Steel Sections and Plates. (2015) Steel Bridge Group: Guidance Notes on best practice in steel bridge construction (6th Issue).06 Transport of steelwork by road 26 / 27 //www. 51/10).05 Marking of steelwork Guidance Note 5.02 Weld procedure tests Guidance Note 5. C. 2001. Iles. SCI Steel Bridges: A practical approach to design for efficient fabrication and construction. 2010. 43/07).08 Hole sizes and positions for preloaded bolts Guidance Note 5. 2007.SteelConstruction. 2011. (Publication no.info/Fabrication . SCI Hendy. SCI Guidance Note 4.R. 2009.02 Surface inspection of welds Guidance Note 6. tcpdf. 2012. See also Welding Accuracy of steel fabrication CE marking Corrosion protection Steelwork specification Health and safety External links Safety Schemes in Procurement (SSIP) Steel Construction Certification Scheme (SCCS) Powered by TCPDF (www.info The free encyclopedia for UK steel construction information Further reading Steel Designer’s Manual (7th Edition).org) . The Steel Construction Institute. SteelConstruction.Fabrication. Chapter 33 .
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