1. PURPOSE
1.1 This engineering specification defines the minimum requirements for handling structural steelwork on site.
2. SCOPE
2.1 This specification applies to off-loading, storing, and erection on site by the erection contractor of structural steelwork supplied by Air Products.
3. RELATED DOCUMENTS
3.1 Air Products Engineering Documents 4WEQ-6804 Painting and Corrosion Protection of New Construction for Design Temperatures to 649°C (1200°F) 4ECE-M05 Supply and Fabrication of Structural Steelwork 4ECE-M13 Grouting of Equipment and Structures
3.2 British Standards Institute (BSI) BS EN 1993 Design of Steel Structures
Note: Outside the UK, BS 5950 shall be replaced by the corresponding codes of the country in which the site is located.
4. OFF-LOADING AND HANDLING
4.1 The erection contractor shall be responsible for checking all steelwork immediately on arrival and reporting, to the engineers representative, any shortages or damage that may have occurred prior to off-loading.
4.2 Within 24 hours of delivery, a written report listing all deficiencies and countersigned by the engineer’s representative shall be submitted by the erection contractor to the engineer’s representative.
4.3 When off-loading or handling steelwork, the erection contractor shall employ adequate cranage and equipment for the items handled. All cranage, spreader beams, and other necessary equipment for handling steelwork shall be supplied by the erection contractor.
4.4 Particular care shall be taken in off-loading and handling box panels, transitions, and other flexible items. Panels shall have their edges protected by timber and shall only be handled in the vertical position.
4.5 The erection contractor shall ensure that no damage or excessive stressing occurs during the handling of the steelwork.
4.6 The erection contractor shall make good any damages to steelwork which can be attributed to his negligence, without cost to the engineer’s representative.
5. STORAGE
5.1 Steelwork shall be stored only in the areas allocated by the engineer’s representative.
5.2 All steelwork shall be kept clear of the ground and adequately supported to prevent deformation and excessive stress.
5.3 Joist sections and channels shall be stored with horizontal flanges. All other items shall be stored to prevent water collecting on them.
5.4 Panels shall be stored in an upright position and not placed horizontally. Edges where the panels rest on shall be continuously supported and adequately protected against buckling.
5.5 Identification marks should be visible, where possible.
5.6 When materials are stored in more than one layer, suitable timber packing shall be placed between the layers to prevent damage.
5.7 Bolts shall be stored in labelled bags, which are under cover.
6. ERECTION
6.1 Erection shall be performed in accordance with EN-1993. The contract specifications and drawings shall be subject to the approval of the engineer’s representative.
6.2 Prior to erection, the erection contractor shall check whether all materials are available and advise the engineer’s representative of any deficiencies.
6.3 The erection contractor shall therefore submit a method statement to the engineer’s representative detailing how piping and equipment supported by the structure are to be erected.
6.4 The erection contractor shall not be permitted to make good on any deficiencies by substituting materials allocated for other structures. However, in exceptional circumstances and only with the approval of the engineer’s representative, this can be done provided replacement material is immediately ordered. No delays in general progress of the work shall result from such action.
6.5 The engineer’s representative will replace the deficiencies or instruct the erection contractor in writing to purchase the necessary materials.
6.6 The replacement of missing items shall be at the erection contractor’s expense unless the items were short delivered.
6.7 The steelwork shall be securely tied, bolted, or guyed during erection to ensure stability at all times.
6.8 If discrepancies or lack of fit in members are encountered, it shall be reported to the engineer’s representative.
6.9 The structure shall not be subjected to temporary loads exceeding those for the permanent condition without prior approval in writing from Air Products.
6.10 When cold boxes are clad with panels, the erection contractor shall ensure that all welds around panels and structural members are continuous to achieve an air-tight enclosure, in accordance with relevant drawings.
6.11 When specified in the project specification, the erection contractor shall be responsible for the final grouting of the steelwork in accordance with 4ECE-M13.
6.12 After erection, the erection contractor shall make good on any damage to the primer paint prior to the application of finish coats in accordance with 4WEQ-6804.
6.13 On completion of erection and alignment of structural items, the erection contractor shall check that all bolts are secure and tightened, all safety gates are fully operable, and all open grid flooring is adjusted and fully clipped into location ready for handing over. The erection contractor’s report shall be submitted to the engineer’s representative and site construction manager.
7. ALIGNMENT AND TOLERANCES
7.1 Steelwork shall be deemed plumb level and aligned if the error does not exceed 1:500.
7.2 The variation in the finished overall dimensions of erected structures shall not be larger than the cumulative effect of the fabricating tolerances, as specified in 4ECE-M05 and/or the contract.
7.3 Boxes shall be shimmed and levelled.
8. HEAVY LIFTS
8.1 The erection contractor shall visit site and note layout of foundations and any other features.
8.2 The erection contractor shall study the soil report and obtain ground bearing pressure values at grade. The erection contractor to supply all necessary bearing plates for distribution of loads.