Nuclear power plants - Instrumentation systems important to safety - Pressure transmitters: Characteristics and test methods
|Publication Date:||1 May 2018|
|ICS Code (Nuclear power plants. Safety):||27.120.20|
This document is applicable to general aspects of design, manufacturing and test methods for pressure transmitters used in instrumentation systems important to safety in all nuclear power plants (PWR, BWR, FBR, etc.). The conditions imposed by reactor use are often different from those which occur in non-nuclear applications. Exposure to radiations (mainly neutron, gamma, even beta) is liable to cause alterations in the measurements. Mechanical and electrical properties of transmitters can be affected by nuclear transformations, heating and structural changes. Particular attention is paid to the adoption of standards for the choice of materials and installation. Furthermore, design consideration is given to the effects of high environmental pressure, high temperature, chemical spray, temperature gradients and temperature cycling as well as to the way in which the temperature and pressure measuring system could influence the safety or economic performance of the reactor.
The consequences of nuclear conditions for pressure transmitters lead to onerous requirements regarding qualification.
This document deals with specific requirements for nuclear applications of pressure transmitters including design, materials, manufacturing, testing, calibration and inspection.
For applications in non-nuclear areas of a NPP, IEC standards used for industrial products apply.
This document deals only with transmitters, the boundaries are:
- Sensing elements.
- Electronics converters.
- Electrical connection.
- Process connection.
- Sealed systems.
Instrumentation systems using pressure transmitters as components (such as flowmeter, level measurement) or other components connecting to transmitters (such as sensing lines, valves) are not in the scope of this document.
Remote seals are considered as components of transmitters and are treated.