Manufacturing Surveillance
Basically valid for welded structures, but correspondingly transferable to other components, too, before commencement of production the following documents have to be reviewed at the welding shop:

Valid QM-certificate according to ISO 9001, quality management: QM-manual, QM-procedures- and working instructions, welding shop approval (verification of suitability), qualification verifications of the welding personnel (welder exam e.g. EN 287 or ISO 9606), qualification verification of the welding supervision personnel (EWE), qualification verification and equipment of the personnel for non-destructive testing Welding Procedure Tests (WPAR), licences for welding fillers, Welding Procedure Specifications (WPS), design drawings and WPS are examined concerning conformity with the design documentations (drawings and preliminary welding instructions, which were submitted for design assessment.

The following tests have to be carried out in regular inspections during production: Review of the material certificates according to EN10204 (3.1C or 3.2C) of the steel manufacturer, checks of the records of the non-destructive tests, inspection of the manufacturing process and the performance of the non-destructive tests and a final inspection of finished components:

• General state appearance
• Dimensions and tolerances
• Layer thicknesses of corrosion protection
• General state
• Damages
• Verification of retraceability of the components and the materials used / semi-finished products
• Inspection of other quality documentations and goods issue control

Transportation- and Installation Surveillance
During transportation and installation GL Renewables Certification will carry out surveillance of shipping and lashing for sea transport, the observance of weather conditions for sea transport, installation of the support structure inclusive lifting operations and the installation of machinery and rotor blades. The general appearance of the components before and after installation, the proper implementation of shipping, lashing, transportation and installation according to the design documentation, the inspection concerning damages and corrosion protection and the inspection of the traceability and numeration of the components are examined.

Monitoring and surveillance
GL Renewables Certification provides Monitoring and Surveillance, comprising the fabrication of critical components, geometry and corrosion protection, tracebility of components, transport and installation, witnessing of commissioning and periodic monitoring.