Standard No.:	GB/T 43550.1-2023
English Name:	Mechanical pencils and leads for general use—Classification|| dimensions|| quality and test methods—Part 1: Mechanical pencils
Chinese Name:	一般用途活动铅笔和铅芯 分类、尺寸、质量和试验方法 第1部分：活动铅笔
Chinese Classification:	Y50    Culture, education and drawing instruments, notebooks and cards
Professional Classification:	GB    National Standard
Issued by:	SAMR; SAC
Issued on:	2023-12-28
Implemented on:	2023-12-28
Status:	valid
Language:	English
File Format:	PDF
Word Count:	7500 words
Price(USD):	225.0
Delivery:	via email in 1~3 business day

Mechanical pencils and leads for general use - Classification, dimensions, quality and test methods - Part 1: Mechanical pencils 1 Scope This document specifies classification, dimensions, quality and test methods for hand-held mechanical pencilss which hold and feed out a lead, and are used for general writing. It is also applicable to multi-function pens equipped with a mechanical pencil unit, However, those pencils attached to machinery instruments such as a plotter are excluded. 2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document, For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 20318-2, Mechanical pencils for general use - Classification, dimensions, quality and test methods Part 2: Black leads Note: GB/T 43550.2-2023, Mechanical pencils and leads for general use - Classification, dimensions,quality and test methods - Part 2: Black leads (ISO 20318-2:2019, IDT) 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 20318-1 and the following apply. ISO and lEC maintain terminological databases for use in standardization at the following addresses ——ISO Online browsing platform: available at https://www.iso.org/obp ——IEC Electropedia: available at http://www.electropedia.org/ 3.1 mechanical pencil writing instrument which holds and feeds out a lead 3.2 multi-function pen writing instrument which can be equipped with two or more writing units (mechanical pencil unit and refills of gel ink ball pen or ball-point pen) Note: At least one of these units is a mechanical pencil unit. 3.3 marking diameter numerical symbol used for classification of mechanical pencils Note: 'This corresponds to the classification of leads for mechanical pencils specified in ISO 20318-2 3.4 nose cone front part of a mechanical pencil Note 1: Varieties include a nose cone without a guide pipe, a nose cone with a fixed guide pipe and a nosecone with a moving guide pipe. Note 2: See Figures 1 and 2. 3.5 bore size inside diameter of the guide pipe or a nose cone without a guide pipe, through which a lead emerges 3.6 residual length of lead length of a lead remaining in a nose cone when approaching a state where writing is impossible as are sult of dislocation of the lead from the chuck by pushing 4 Classification 4.1 General Mechanical pencils shall be classified according to the type of mechanism (see Table 1 and Figures 1and 2) and the marking diameter (see Table 2). The classification, quality, dimensions and test methods of the lead for mechanical pencils shall be in accordance with ISO 20318-2. 4.2 Type according to mechanism The type according to mechanism shall be in accordance with Table 1