Background
Carbon steel piping and components of the secondary circuit of VVER reactor power plants are affected by the erosion corrosion process. The erosion corrosion process results in wall thinning of piping during operation of the plant. Wall thinning of pressurized piping and components if not detected leads to pipe rupture, plant shut down and the possibility of fatal accidents involving the operation personnel working close to the affected pipe/component. The erosion corrosion process is influenced by a large number of parameters like flow velocity, fluid temperature, water chemistry parameters such as oxygen concentration and pH, material composition and piping geometry. The complexity of their functional interdependencies and the large effort involved in analysis of entire piping systems in power plants requires besides the weak point analysis also measurement of the remaining wall thickness.
The subject of the R1.03/94D project was to provide Kalinin NPP with measurement equipment to monitor the erosion corrosion in secondary circuit piping systems. The supplies included the delivery of ultrasonic thickness measurement devices, ultrasonic flaw detectors and necessary set of ultrasonic probes, plus computer and software for data acquisition and further analysis. This equipment was purchased through a TACIS supply contract (see R1.03/94D[1]). The purpose of the present contract was to perform an independent inspection of the equipment supplied under R1.03/94D[1].

Objective
The objective of the contract was to perform an independent inspection of goods to certify their origin according to the Community Customs Code. According to Tacis General Conditions for Supply Contracts financed by the EC Funds, goods supplied must originate in a Member State of the European Community or in one of the Beneficiary Countries of Tacis Programme. The goods were to be inspected at the supplier's premises in Belgium. The equipment to be inspected comprised:

• Digital ultrasonic thickness gauge DMS with echo verification and data recorder, qty 3
• Ultrasonic flaw detector USN52, qty 2

Results
The inspection services were performed on 23 October 2000 and a report of the findings was provided to the EC. The goods were accepted for EC financing.