Personnel competence qualification

Correct installation of the sealing elements is essential in their optimal and safe operation of a system containing pressurised bolted connections and in the achievement of the highest performance from a pressurised bolted connection. If improperly assembled, even most performant sealing will not work as it should. Improper assembly of the sealing will cause not only leaks, but also stops of the production process – that means high costs – or worse, a catastrophe. Studies showed that  main cause for flange joint failures are due to improper handling of the sealing elements and incorrect assembly. Design norms for pressurised bolted connections such as EN 1591-1 require controlled bolt tightening. Therefore, competent bolting technicians are needed so that the specified bolt load tolerances can be met and, where appropriate, the specified tightness requirement can be achieved.

At present, there are two standards with reference to qualification of  personnel competency in the assembly of the bolted connections: SR EN 1591-4-2014, ASME PCC-1-2013 Appendix A

1. EN 1591-4:2014

 According to this norm, key aspects for achieving proper competency are:

• theoretical knowledge combined with practical experience gained on site or by simulated workshop activities;
• assessment by a competent assessor to verify that the required knowledge, skill and ability has been gained and can be applied in accordance with an operating procedure.

EN 1591-4:2014 sets out the training syllabi for not only the bolting technicians, who actually disassemble, assemble and tighten bolted joints that in service will be pressurized, but also the syllabi for the personnel who supervise those technicians, the responsible engineers. The aim of the presented European standard is to establish the  skills required to safely and successfully disassemble, assemble and tighten pressurized bolted joints of a joint capable of maintaining a leak-free status throughout its’ service life.

Bolting technicians have to assemble bolted connections of different levels of complexity. For this reason, training matrices dealing with bolted connections of various levels of complexity and for different types of pressurised bolted connections are given in this norm. The modular structure created allows a bolting technician, once competency in the foundation level has been achieved, to obtain competency in higher levels as required.

Higher levels of  competency refer to special applications such as: heat exchangers, fragile flanges, compact flanges and clamp connectors.

2. ASME PCC-1:2013 Appendix A

This appendix is not mandatory, and provides guidelines for establishing uniform criteria for the training and qualification of personnel competency in the assembly of the bolted connections.  It also provides guidelines for quality control program. The recommendations presented in this appendix is intended to be a guide and can be applied differently by each user. The decision that these guidelines to be applied or not lies entirely with the user. The appendix provides for the qualification of operators three components for the operators qualification: training, practice and experience.  This appendix may be applied to personnel involved in the assembly / disassembly or quality control for pressure vessels, pipes and tanks with bolted joints. Depending on the requirements of training and qualifications and also on the duties and responsibilities the provisions of this norm are addressed to:- Qualified Bolting Specialists- Qualified Senior Bolting Specialists- Qualified Bolting Specialists Instructors Additional qualifications may be obtained for power equipment, heat exchangers and special joints.