GB/T 25708-2010Ball mills and rod mills (English PDF)

Foreword

Since implementation date of this Standard, previous Standard JB/T 1406-2002 Ball-mill and rod-mill is abolished. This Standard was proposed by China Machinery Industry Federation. This Standard shall be under the jurisdiction of National Technical Committee (SAC/TC 88) on Mining Machinery of Standardization Administration of China. The responsible drafting organization of this Standard. Luoyang Mining Machinery Engineering Design & Research Institute Co., Ltd. The participating drafting organizations of this Standard. Shenyang Heavy Machinery Group Co., Ltd, CITIC Heavy Industries Co., Ltd, Jinan Heavy Machinery Joint-stock Co., Ltd, Hengyang Heavy Machinery Co., Ltd, Sinosteel Co., Ltd., and Shendong Shankuang Machinery Co., Ltd. The chief drafting staffs of this Standard. Zhang Xiao, Li Chunran, Wang Jisheng, Yu Xiao, Gao Junkun, Zhou Xiaoping, Zhao Heng, Yang Xianli, Liu Wanhua, Wang Jianhua, Fan Yongqing, and Wang Chunhong. Ball mill and Rod mill

1 Scope

China's national standard for ball mills and rod mills. It specifies the types and basic parameters, the technical requirements, the test methods, the inspection rules and the marking, packaging, transport and storage of tumbling mills charged with steel balls or rods. A grinding mill is the largest energy consumer in a mineral processing plant by a wide margin - comminution accounts for the majority of a concentrator's power - and the reason is that grinding is inherently inefficient: almost all the energy put into a tumbling mill becomes heat and noise, and only a small fraction creates new mineral surface. That fact makes the machine's parameters commercially decisive rather than merely technical, since a small difference in efficiency is a large sum over a mill's life. The two types in the standard grind differently. A ball mill is charged with steel balls, which grind mainly by impact and attrition and produce a wide size distribution including a lot of fines. A rod mill is charged with long steel rods that lie parallel and contact the coarser particles first, because the rods bridge across the fines - so it acts as a size-selective crusher and produces a narrower distribution with less overgrinding, which matters where the downstream process is sensitive to slimes. The requirements are those of a very large slow-turning machine carrying a heavy load: the shell and its manufacture, the trunnions and bearings, the girth gear and drive, the liners and their attachment, the critical speed and the operating speed as a fraction of it, the charge volume, and the capacity and power draw. And the tests are of a machine that cannot be run at full load in a works, so much of the verification is dimensional and of the no-load running. Issued on 23 December 2010 and in force since 1 July 2011.

This Standard specifies ball-mill and rod-mill's types and basic parameters, technical requirements, test methods, inspection rules, marking and operation instructions, packaging, transportation and storage. This Standard applies to ball-mills and rod-mills that grind ores, rocks and other suitable materials of various hardness in wet and dry processes (hereinafter referred to as mills).

2 Normative references

The articles contained in the following documents have become part of this Standard when they are quoted herein. For the dated documents so quoted, all the modifications (excluding corrections) or revisions made thereafter shall not be applicable to this Standard. For the undated documents so quoted, the latest editions shall be applicable to this Standard.

GB/T 191 Packaging - Pictorial marking for handling of goods ( GB/T 191-2008, ISO 780.1997, MOD)

GB/T 700 Carbon structural steels ( GB/T 700-2006, ISO 630.1995, NEQ)

GB/T 1174 Cast bearing metals ( GB/T 1174-1992, neq ISO 4382-1.1991)

GB/T 1348 Spheroidal graphite iron castings ( GB/T 1348-2009, ISO 1083.2004, MOD)

GB/T 1804-2000 General tolerancesTolerances for linear and angular dimensions without individual tolerance indications (eqv ISO 2768-1.1989)

GB/T 3768 Acoustics - Determination of sound power levels of noise sources using sound pressure - Survey method using an enveloping measurement surface over a reflecting plane ( GB/T 3768-1996, eqv ISO 3746.1995)

GB/T 5226.1 Electrical safety of machinery - Electrical equipment of machines - Part

5 Test method

5.1 Appearance inspection is conducted visually; there shall be no significant defect.

5.2 During complete machine idling, noises shall be determined by the method specified in GB/T3768.

5.3 Mill shall be conducted for idling test and meets the following requirements.

6 Inspection rules

6.1 Inspection classification Inspection is divided into exit-factory inspection and type inspection.

7 Marking and operation instructions

7.1 Product label shall be fixed onto an apparent and appropriate position of each set of mill. The label shall comply with the provisions of GB/T13306 and indicate following contents.

7.2 Operation instructions of mill shall comply with the provisions of GB/T 9969.

7.3 Packing mark of mill shall comply with the provisions of GB/T 191.

8 Packaging, transportation and storage

8.1 Packages of mill shall comply with the provisions of JB/T5000.13.

8.2 Mill packing is divided into enclosed packing, nude packing, bundled packing, etc. Components and parts shall be fixed firmly in cases during packing.

8.6 Following technical documents shall be attached.

8.7 Mill shall have safety measures of preventing deformation and damage during transportation.

8.8 Packages of mills shall comply with land or sea transportation requirements.

8.9 Mill storage shall meet the following requirements.