核仪器-用于测定岩石密度的地球物理钻孔仪器（“密度测井

[中文适用范围]： IEC 61874:2025适用于由以下设备组成的系统： - 一个配有准直放射性同位素（伽马）源（仅在实际测量期间使用）和用于测量散射伽马辐射的探测器单元的井下测井探头； - 一个提升系统和深度测量系统； - 其他仪器和设备（如电源、脉冲转换器/放大器、计数器、记录仪、信号处理和显示单元）。 本文件定义了相关术语，规定了设备类型、设计和一般技术要求，以及具体的辐射性能、电气、机械、安全和环境性能要求。它还定义了测试和校准程序，涵盖了电气安全和辐射防护问题。此外，本文件还对制造商操作和维护文档（或证书）中应包含的项目提出了建议。 本文件的目的是规定用于井下测井中确定原位岩体体积密度的核仪器的设计要求和性能特性。通过使用适当的响应图表，测量结果可以转化为岩性及孔隙度信息。 [外文原描述]： IEC 61874:2025 applies to equipment consisting of: - a borehole logging probe equipped with a collimated radioisotope (gamma) source (during the actual measurements only) and a detector unit to measure scattered gamma radiation; - a hoisting system and depth measuring system; - other instruments and devices (power supply, pulse converter/amplifier, ratemeter, recorder, signal processing and readout units). This document defines the terminology, specifies the types of apparatus, design and general technical requirements, specific radiation performance, electrical, mechanical, safe and environmental performance requirements. It also defines test and calibration procedures and covers electrical safety and radiation protection issues. Further, it gives recommendations about items included in the manufacturer's operation and maintenance documentation (or certificate). The purpose of this document is to specify design requirements and performance characteristics of nuclear instrumentation used in boreholes to determine bulk rock density in situ. With suitable response charts the measurements can be equated to rock lithology and porosity.