Continuous quality surveillance
During the construction of hydroelectric plants, poor quality can have a hugely negative impact on construction time, plant performance and safety. A method known as the Continuous Quality Surveillance Scheme can keep the manufacturing of the most critical components, such as pressure parts, rotors and valves, under control with a view to minimising the Cost of Poor Quality (COPQ). This can be effective when used in a systematic manner and requires the formalisation of some main elements such as the Pre-Inspection Meeting (PIM) at the start of construction; the Inspection and Test Plan (ITP), with specific witness points for all critical manufacturing phases; and the use of Notification for Inspection (NOI) to formalise the intervention points.
Hydroelectric power plants need strict requirements with regards to the safety and productivity of the plant. Poor quality revealed during the construction, commissioning and operation of the plant may lead to huge costs with regards to safety (loss of human life), as well as productivity (in a few days loss of production costs may overcome the single component cost).
The sooner manufacturing defects (dimensional, non-conforming raw material, NDT detectable defects) are found, the less overall quality and delivery time will be affected. Introducing a follow-up method specifically intended to minimise the Cost of Poor Quality (COPQ) during manufacturing can considerably reduce safety risks and failure costs, keeping general extra costs down. Such methodology, not unknown in the hydroelectric industry, requires a systematic approach in order to achieve the highest effectiveness (as occurs in other industrial sectors such as the nuclear, oil and gas industry), and the formalisation of fundamental elements.