Execution of steel structures and aluminium structures. Part 2. Bolted connections with small ratio of clamp lengths relative to bolt diameter subject to significant vibrations, such as storage racks, shall use a locking method.
Unless otherwise specified, preloaded assemblies do not require additional locking devices. Bolts and nuts shall not be welded, unless otherwise specified. This restriction does not apply to special weld nuts according to e.
The bolt length shall be chosen such that after tightening the following requirements are met for bolt end protrusion beyond the nut face and the thread length. The length of protrusion shall be at least the length of one thread pitch measured from the outer face of the nut or additional locking devices to the end of the bolt for preloaded and non-preloaded assemblies. If itis intended that a connection utilizes the shear capacity of the unthreaded shank of bolts, then the dimensions of the bolts shall be specified to allow for the tolerances on the length of the unthreaded portion.
For non-preloaded bolts, at least one full thread in addition to the thread run out shall remain clear between the bearing surface of the nut and the unthreaded part of the shank.
Any nut and polt assembly where the nut does not run freely shall be discarded. If a power tool is used, either of the following two checks may be used: a for each new assembly lot of bolting assemblies their compatibility may be checked by hand assembly before installation; b for mounted bolting assemblies but prior to tightening, sample nuts may be checked for free-turning by hand after initial loosening.
Nuts shall be assembled so that their designation markings are visible after assembly. If required, it shall be specified whether washers are to be placed under the nut oF the bolt head, whichever is rotated, or both.
For single lap connections with only one bolt row, washers are necessary under both bolt head and the nut, unless otherwise specified NOTE The use of washers can reduce local damage to metal coatings particularly where these are thick coatings, Washers used under heads of preloaded bolts shall be chamfered according to EN and positioned with the chamfer towards the bolt head.
Washers according to EN shall only be used under nuts. Plate washers according to 5. The combined thickness of the additional washers shall not exceed 12 mm. Washers to EN shall not be used for assemblies to EN and EN , Ifadditional washers or plate washers are used, the connection detail should be checked to ensure that the shear plane for bolts with a shank has not been relocated into the threaded portion of the bolt. Dimensions and steel grades of plate washers shall be specified.
Each bolting assembly shall be brought at least to a snug-tight condition, with special care being given to avoid over-tightening especially short bolts and M The tightening process shall be carried out from bolt to bolt of the group, starting from the most rigid part of the connection and moving progressively towards the least rigid part.
To achieve a uniform snug-tight condition, more than one cycle of tightening, may be necessary. NOTE1 The most rigid part of a cover plate connection of an I section is commonly in the middle of the connection bolt group. The most rigid parts of end plate connections of sections are usually beside the flanges. This clause does not deal with corrosion protection for which requirements are specified in Clause 10 and Annex F.
The area of contact surfaces in preloaded slip-resistant connections shall he specified. After fash sweop blasting the appearance of a matt surface indicates that a soft surface layer of un-alloyed zinc has been removed 4 Dry thickness to be within 40 ym to 80 ym range.
Otherwise, the slip factor, which shall be determined by test as specified in Annex G, and the contact surfaces shall be prepared in accordance with the tested samples.
The following precautions shall be taken prior to assembly: a the contact surfaces shall be free from all dontaminants, such as oil, dirt or paint. Burrs that would prevent solid seating of the connecting parts shall be removed; b uncoated surfaces shall be freed from all films of rust and other loose material. In the latter case, the boltingassemblies, the Lightening method, the tightening parameters and the inspection requirements shall also be specified.
The k-class as-delivered condition according to EN of the bolting assembly shall be in accordance with Table 19 for the method used. Foundation bolts intended to move in sleeves should be provided with sleeves three times the diameter of the bolt with a minimum of 75 mm.
Areas of supports that require protection against rust staining should be identified and appropriate protection provided. Compensation for settlement of supports is acceptable, unless otherwise specified. This shall be done by grouting or packing between steelwork and support. NOTE The compensation will generally be placed beneath the bearing, 9. If packings are subsequently to be grouted, they shall be placed so that the grout totally encloses them witha minimum cover of 25 mm, unless otherwise specified.
For bridges, packings shall not be left in position, unless otherwise specified. Thank you for interesting in our services. Related Papers. By Ezgi Kizileroglu. PDF Price. Not a Member? Read free for days Sign In. Affiliation List of ICS codes. Generation in process Specification for materials, fabrication and erection: hot rolled sections AMD Withdrawn. Specification for materials, fabrication and erection - Rolled and welded sections No longer current but cited in Building Regulations guidance.
This is that the first five joints made to the same new WPS require inspecting to twice the extent specified in Table 24 and to an EN acceptance level of Quality Level B. The reason for this additional testing is to establish that the new WPS can provide the required quality in production — as distinct from that which can be provided during procedure qualification testing.
Specific industry standards are being developed which, although based on BS EN Part 2, will contain additional requirements that may mean further qualification testing will be needed. Once such specifications are available then these may form part of a Job Knowledge article covering the key differences and additional requirements.