GB/T 25845-2018Industrial gamma-ray level meter (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009. This standard replaces GB/T 25845-2010 "Industrial gamma ray level gauge", compared with GB/T 25845-2010, except for editorial repair The main technical changes changed are as follows:

--- Increased integrated level gauge type [see 3.1b)];

---Modified measurement range, from "100mm~6000mm" to "100mm~8000mm" (see 3.3.1,.2010 edition) 3.3.1);

---Modified the requirements for the switch output signal contact capacity (see 3.3.2,.2010 version 3.3.3);

--- Added the "backlash setting" requirement in the "alarm function" (see 4.7);

--- Added the protection level requirements for the enclosure in the "Protection Requirements" (see 4.15,.2010 edition 4.15);

---Modify the "test method" as "test and test method" (see Chapter 5, Chapter 5 of the.2010 edition);

--- Deleted the contents of the "laboratory analog level device" [see.2010 edition 5.1e)];

--- Removed the content that is not applicable in the "Alarm Function Check" (see 5.8,.2010 Edition 5.8);

--- Increased the test requirements for the "integrated level gauge remote commissioning" function (see 5.15);

--- Added the "Decommissioning Treatment of Radioactive Sources" project (see 7.6). This standard is proposed and managed by the China Petroleum and Chemical Industry Federation. This standard was drafted. Tianhua Chemical Machinery and Automation Research and Design Institute Co., Ltd., chemical industry instrumentation quality supervision and inspection Xin, Gansu Junli Engineering Technology Co., Ltd. The main drafters of this standard. Zhao Wanxiang, Xue Feng, Liu Zhibin, Fang Jiang, Liu Yu, Zhang Xuewu. The previous versions of the standards replaced by this standard are.

---GB/T 25845-2010. Industrial gamma ray level gauge

1 Scope

GB/T 25845-2018 is the Chinese national standard on industrial gamma-ray level meter, in the field of chemical technology. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 28 December 2018 by the State Administration for Market Regulation; Standardization Administration of China, and has been in force since 1 November 2019. Classification: ICS 71.120, CCS G98. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This standard specifies the type, requirements, inspection and test methods, inspection rules and standards for industrial gamma ray level gauges (hereinafter referred to as level gauges). Zhi, instruction manual, packaging, transportation and storage. This standard applies to industrial gamma ray level gauges.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article. Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB 3836.1 Explosive atmosphere - Part 1. General requirements for equipment Explosive atmospheres - Part 2. Equipment protected by flameproof enclosure "d"

GB 4075 Sealed radioactive sources General requirements and classification

GB/T 4208-2017 enclosure protection grade (IP code)

GB 8702 electromagnetic environment control limit

GB/T 8993 Nuclear instrument environmental conditions and test methods

GB/T 9969 General guidelines for the use of industrial products

GB 11806 Safe Transport Procedure for Radioactive Material General technical conditions for

GB/T 13384 mechanical and electrical product packaging

GB 14052-1993 Radiation safety performance requirements for isotope meters installed on equipment

3 Type

3.1 Structure type The level gauge is divided into two types of structure.

a) Split type. consists of three parts. radioactive source, detector and converter;

b) Integrated type. It consists of two parts. radioactive source and detector.

Note. "Separate type" means that the detector and converter are separated, and the signal detected by the detector is sent to the converter for processing. "Integrated" means removing the converter and integrating the converter and detector.

3.2 Product Classification The level gauge is divided into switch type and continuous type.

3.3.1 Measurement range. 100mm~8000mm.

3.3.2 Output signal.

a) The switch output signal is a dry contact signal, and the contact capacity should be no less than 20W;

b) The continuous output signal is a DC4mA~DC20mA current signal;