OS-C501

Offshore Standard DNV-OS-C501, November 2013
Sec.11 Fabrication – Page 171
3.7.7 Hole diameters positions and tolerances shall be specified for bolted connections.
3.7.8 Washer sizes or other supports shall be specified.
3.7.9 Torque of the bolts shall be specified.
3.7.10 Bolted joints shall be verified independently during production for high safety class components.
Whether the verification shall be done by the manufacturer himself, by the customer, or by a third party should
be decided by the project.
3.8 Injection of resin and cure
3.8.1 The viscosity of the resin should be specified and controlled for all processes where the flow is important
(see also [3.5.5]. As a minimum the gel time should be checked.
3.8.2 The flow patterns of injection processes shall be documented. Every part of the component shall be filled
with resin. No paths shall be blocked by resin that is already cured.
3.8.3 The curing schedule shall be specified and documented. A log shall be kept for component of normal or
high safety class. The accuracy of the process shall be verified.
3.9 Evaluation of the final product
3.9.1 A procedure should be given to describe the evaluation of the finished product.
4 Quality assurance and quality control
4.1
4.1.1 A programme shall be established to ensure constant quality of the laminates that are produced.
4.1.2 The programme may rely mainly on testing of the product or it may utilise the control of production and
machine parameters.
4.1.3 Tests shall be carried out to check whether a consistent quality of the product or products is maintained.
4.1.4 Which tests should be carried out depends on the processing method and the particular structure. The
principles given here shall be followed, but details may be changed.
4.1.5 All tests that are performed for quality control shall also be performed on the materials that were used to
obtain the design properties. The results of the tests shall be used a reference values for all following QC tests.
4.1.6 Allowable ranges of test results shall be established for all tests.
4.1.7 The easiest way to establish ranges of test results is to produce the materials for obtaining design data
with the worst acceptable process parameters. Such values can then be taken as minimum values.
4.1.8 Statistical process control methods may be used.
5 Component testing
5.1 General
5.1.1 Testing on components is done to detect possible manufacturing defects. The testing is not intended to
qualify design aspects. These tests are described in Sec.10.
5.1.2 Testing on the system addresses the same aspects as for components. In addition the interaction between
the components is tested to detect possible mistakes in the way the components were put together.
5.1.3 The testing to check for fabrication errors shall be considered in the design analysis. No unintended
damage (failure mechanisms, e.g. matrix cracking) shall be introduced into the structure by the tests.
5.2 Factory acceptance test and system integrity test
5.2.1 The factory acceptance test (FAT) is performed before the component leaves the factory. The test should
identify manufacturing errors before the component leaves the factory.
5.2.2 The FAT should be performed on all structures with safety class normal and high according to the
requirements for pressure testing or other testing.
5.2.3 It is common practise to perform a FAT test, especially for pressurised components. The test is
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