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DL/T 681.1-2019: Specification for wear-resistant parts of coal mill in coal-fired power plants — Part 1: Ball grinding mill, grinding balls and liner
Status: Valid DL/T 681.1: Evolution and historical versions
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Specification for wear-resistant parts of coal mill in coal-fired power plants — Part 1: Ball grinding mill, grinding balls and liner
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DL/T 681.1-2019
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| DL/T 681-2012 | English | 679 |
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Specification for wear resistant parts of coal mill in coal-fired power plants
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Specification for wear-resistant fittings of mill-coal
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Basic data | Standard ID | DL/T 681.1-2019 (DL/T681.1-2019) | | Description (Translated English) | Specification for wear-resistant parts of coal mill in coal-fired power plants �� Part 1: Ball grinding mill, grinding balls and liner | | Sector / Industry | Electricity & Power Industry Standard (Recommended) | | Classification of Chinese Standard | F29 | | Classification of International Standard | 27.100 | | Word Count Estimation | 19,150 | | Date of Issue | 2019-06-04 | | Date of Implementation | 2019-10-01 | | Older Standard (superseded by this standard) | DL/T 681-2012 | | Regulation (derived from) | Natural Resources Department Announcement No. 7 of 2019 | | Issuing agency(ies) | National Energy Administration | DL/T 681.1-2019: Specification for wear-resistant parts of coal mill in coal-fired power plants — Part 1: Ball grinding mill, grinding balls and liner
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Specification for wear-resistant parts of coal mill in coal-fired power plants-
Part 1.Ball grinding mill, grinding balls and liner
ICS 27.100
F 29
People's Republic of China Electric Power Industry Standard
Replace DL/T 681-2012
Technical requirements for wear parts of coal mill in coal-fired power plant
Part 1.Ball mill ball and liner
2019-06-04 released
2019-10-01 implementation
Issued by National Energy Administration
Table of contents
Preface... 2
1 Scope... 4
2 Normative Reference Documents... 4
3 Terms and Definitions... 5
4 Technical requirements... 5
5 Test method... 9
6 Inspection rules... 10
7 Marking, packaging, storage and transportation... 11
Appendix A (Normative Appendix) Measurement and calculation method of grinding ball breaking rate... 12
Appendix B (Normative Appendix) Impact Fatigue Life Test Method and Requirements of the Ball Falling Ball Method... 13
Appendix C (Normative Appendix) Calculation Method of Ball Loss for Grinding Balls... 14
Appendix D (Normative Appendix) Calculation Method of Out-of-round Rate of Grinding Balls... 15
Appendix E (informative appendix) Metallographic structure and use characteristics of grinding balls and liners... 16
Appendix F (informative appendix) Approximate conversion relationship table between Brinell hardness and Rockwell hardness value... 18
Foreword
This standard DL/T 681 "Technical Conditions for Wear Parts of Coal Mills in Coal-fired Power Plants" is divided into the following three parts.
--Part 1.Ball mill ball and liner;
--Part 2.Medium-speed grinding roller, roller sleeve grinding disc liner grinding ring and hollow grinding ball;
--Part 3.Fan grind impact plate guard hook and armor.
This part is part 1 of DL/T 681.ball mill ball and liner.
This part of this standard is in accordance with the rules given in GB/T 1.1-2009 "Guidelines for Standardization Part 1.Standard Structure and Compilation"
Drafting.
This part of this standard replaces DL/T 681-2012 "Technical Conditions for Wear-resistant Parts of Coal-fired Power Plant Coal Mills", compared with DL/T 681-2012,
The main technical content changes are as follows.
--Keep the original serial number DL/T 681 of the independent power industry standard unchanged, and the general name in the "Technical Conditions for Wear Parts of Coal-fired Power Plants"
It is referred to as Part 1 of DL/T 681.
--Modified and added some terms and definitions.
-Increased the small diameter specifications of 20mm and 25mm grinding balls and diameter tolerances.
--Added ZQCr26Mn2W, ZQCr18Mn2W, ZQCr12Mn2W cast grinding balls, and added D(Z)Q60CrMn
Brand forging (rolling) grinding balls.
--Added ZGM40Mn2SiCrMo, ZGM50SiCrNiMo, ZGM120Mn13VTi and ZGM120Mn18Cr2 grades
Liner.
-Increased the weight tolerance and shape tolerance requirements.
-Adjusted the chemical composition and mechanical properties of some cast grinding balls, forging (rolling) grinding balls and liners.
--Updated the wear-resistant cast steel grade ZGM.
--Added some notes.
--Some paragraphs have been edited.
--- Added appendix A (normative appendix) the determination and calculation method of grinding ball crushing rate.
--- Added appendix B (normative appendix) impact fatigue life test method and requirements of grinding ball falling ball method.
--- Added appendix C (normative appendix) ball loss calculation method for grinding balls.
--- Added appendix D (normative appendix) the calculation method of out-of-round rate of the grinding ball.
--- Added appendix F (informative appendix) approximate conversion relationship table between Brinell hardness and Rockwell hardness value.
This standard was proposed by the China Electricity Council.
This standard is under the jurisdiction of the Power Station Metal Materials Standardization Technical Committee.
The organization responsible for drafting this standard. North China Electric Power University, Nantong Gaoxin Wear-resistant Technology Co., Ltd., Tianjin Wanlixinsheng New Material Technology
Research Institute Co., Ltd., Xi'an Thermal Power Research Institute Co., Ltd.
Participated in the drafting of this standard. Datang Baoding Thermal Power Plant, Xinghua Dongchang Alloy Steel Co., Ltd., Tianjin Lixinsheng New Material Technology Co., Ltd.
Company, Ningguo Huada Wear-resistant Material Co., Ltd., Dongying Shengli Power Plant, Handan Huiqiao Composite Material Technology Co., Ltd., Luoyang
Huashi Wear-resistant Material Manufacturing Co., Ltd., Guodian Power Handan Thermal Power Plant, National Power Industry Wear-resistant Materials Experimental Research Center, Xuzhou Sinoma
Tianyuan Heavy Machinery Co., Ltd., National Power Industry Metal Wear-resistant Parts Quality Supervision, Inspection and Testing Center, Shanxi Zhongneng Construction Power Equipment Co., Ltd.
Company, Shandong Huamin Steel Ball Co., Ltd., Hunan Hongyu Wear-resistant New Material Co., Ltd., Beijing Jiake Xinxing Technology Co., Ltd.,
Xinjiang Tiandian Industry and Trade Co., Ltd., Shanxi Yingrental Wear-resistant Material Co., Ltd.
The main drafters of this standard. Wen Xinlin, Li Honghai, Ma Shaolei, Qian Bing, Shi Weidong, Li Dongqu, Sun Lidong, Ge Jun, Li Yingchun,
Zhang Mingchang, Jia Jianmin, Liu Zhenying, Liu Shutao, Ma Yufeng, Xing Zhenguo, Li Xiaoqing, Ma Yong, Wen Peng, Zhang Desheng, Liu Sheng, Hou Yumin,
Wang Yingping, An Liqiang, Ding Haimin, Sun Yu, Li Na, Wu Xuesong, Yao Fengmin, Shen Guangming, Yao Junmin, Niu Chaowei, Liu Dongxin, Yuan Liqiang,
Ji Guosheng, Li Zongyao, Liu Zhiyuan, Luo Xinlei, Ni Hongning, Chen Changshun, Wei Guo, Zhou Liang, Li Haiyan, Yin Xuefei, Feng Hongxi, Zheng Yupeng,
Zhu Zhengfang, Liu Junye, Wang Sheng.
This standard is interpreted by North China Electric Power University and the National Electric Power Industry Wear-resistant Materials Experimental Research Center.
This standard replaces DL/T 681-2012 from the date of implementation.
The previous editions replaced by this standard are as follows.
DL/T 681-1999 was issued on August 2,.1999.
DL/T 681-2012 was released on December 1,.2012; this is the second revision.
The opinions or suggestions during the implementation of this standard are fed back to the Standardization Management Center of China Electricity Council (No. 2 Baiguang Road, Beijing)
One, 100761).
Technical requirements for wear parts of coal mill in coal-fired power plant
Part 1.Ball mill ball and liner
1 Scope
This part of DL/T 681 specifies the technical requirements, test methods, inspection rules and marking, packaging, and packaging of wear parts for ball mills in coal-fired power plants.
Storage and transportation.
This section applies to ball mill balls and liners of coal-fired power plants; other wear-resistant parts of similar working conditions can be used as reference.
2 Normative references
The following documents are essential for the application of this document. For dated reference documents, only the dated version applies to this document.
For undated references, the latest version (including all amendments) applies to this document.
GB/T 223.4 Determination of manganese content in iron, steel and alloy by potentiometric titration or visual titration
GB/T 223.5 Determination of acid-soluble silicon and total silicon content of steel
GB/T 223.11 Determination of chromium content in steel and alloy by visual titration or potentiometric titration (GB/T 223.11-2008, ISO
4937.1986, MOD)
GB/T 223.18 Methods for chemical analysis of iron, steel and alloy-The sodium thiosulfate separation-iodometric method for the determination of copper content
GB/T 223.23 Iron, steel and alloy-Determination of nickel content-Dimethylglyoxime spectrophotometric method
GB/T 223.25 Methods for chemical analysis of iron, steel and alloy-The dimethylglyoxime gravimetric method for the determination of nickel content
GB/T 223.26 Steel and alloy determination of molybdenum content-Thiocyanate spectrophotometric method
GB/T 223.43 Determination of tungsten content in iron, steel and alloy by gravimetric method and spectrophotometric method
GB/T 223.59 Steel and alloy determination of phosphorus content-Bismuth phosphomolybdenum blue spectrophotometric method and antimony phosphomolybdenum blue spectrophotometric method
GB/T 223.60 Methods for chemical analysis of iron, steel and alloy-The perchloric acid dehydration gravimetric method for the determination of silicon content
GB/T 223.63 Methods for chemical analysis of iron, steel and alloy. The sodium (potassium) periodate photometric method for the determination of manganese content
GB/T 223.64 Determination of manganese content in iron, steel and alloy by flame atomic absorption spectrometry
GB/T 223.67 Steel and alloy determination of sulfur content-Methylene blue spectrophotometric method (GB/T 223.67-2008, ISO 10701.
1994, IDT)
GB/T 223.68 Methods for chemical analysis of iron, steel and alloy, the determination of sulfur content by potassium iodate titration after combustion in a tube furnace
GB/T 223.69 Steel and alloy carbon content determination after combustion in tube furnace gas volume method
GB/T 223.71 Methods for chemical analysis of iron, steel and alloy, the determination of carbon content by gravimetric method after combustion in a tube furnace
GB/T 223.72 Determination of Sulfur Content in Steel and Alloy by Gravimetric Method
GB/T 228.1 Tensile test of metallic materials Part 1.Room temperature test method (GB/T 228.1-2010, ISO 6892-1.
2009, MOD)
GB/T 229 Charpy Pendulum Impact Test Method for Metallic Materials (GB/T 229-2007, ISO 148-1..2006, MOD)
GB/T 230.1 Rockwell hardness test of metallic materials Part 1.Test method (A, B, C, D, E, F, G, H, K,
N, T scale) (GB/T 230.1-2009, ISO 6508-1..2005, MOD)
GB/T 230.2 Rockwell hardness test of metallic materials Part 2.Hardness tester (A, B, C, D, E, F, G, H, K, N,
T scale) inspection and calibration
GB/T 230.3 Rockwell hardness test of metallic materials Part 3.Standard hardness blocks (A, B, C, D, E, F, G, H, K,
N, T scale) calibration
GB/T 231.1 Brinell hardness test of metallic materials Part 1.Test method (GB/T 231.1-2009, ISO 6506-1.
2005, MOD)
GB/T 1184 shape and position tolerance without tolerance value
GB/T 2828.1 Sampling inspection procedure by attributes Part 1.Batch inspection sampling plan retrieved by acceptance quality limit (AQL)
(GB/T 2828.1-2003, ISO 2859-1..1999, IDT)
GB/T 4336 Carbon steel and low alloy steel spark source atomic emission spectrometry method (conventional method)
GB/T 5611 Casting terminology
GB/T 5677 Radiographic testing of steel castings (GB/T 5677-2007, ISO 4993.1987, IDT)
GB/T 5680 Austenitic manganese steel castings (GB/T 5680-2010, ISO 13521..1999, MOD)
GB/T 6060.1 Surface roughness comparison sample casting surface
GB/T 6402 Steel Forgings Ultrasonic Testing Method (GB/T 6402-2008, EN 10228-3..1998, EN 10228-4..1999,
MOD)
GB/T 6414 Casting dimensional tolerance and machining allowance (GB/T 6414-1999, ISO 8062..1994, eqv)
GB/T 7233.1 Ultrasonic testing of steel castings Part 1.General purpose steel castings (GB/T 7233.1-2009, ISO 4992-1.
2006, MOD)
GB/T 9443 Penetration testing of steel castings (GB/T 9443-2007, ISO 4987..1992, IDT)
GB/T 9444 Magnetic particle testing of steel castings (GB/T 9444-2007, ISO 4986..1992, IDT)
GB/T 11351 Casting weight tolerance
GB/T 13298 Metal Microstructure Inspection Method
GB/T 13925 Casting high manganese steel metallography
GB/T 14203 General Rules of Photoelectric Emission Spectroscopy Analysis for Steel and Alloy
GB/T.20066 Sampling and sample preparation methods for the determination of the chemical composition of steel and iron (GB/T.20066-2006, ISO 14284.
1996, IDT)
DL/T 680 Technical conditions for wear-resistant pipelines in the power industry
DL/T 1604 Technical conditions for wear parts of coal crushers in coal-fired power plants
3 Terms and definitions
The following terms and definitions established in GB/T 5611 apply to this standard.
3.1
Abrasive wear
Due to the relative movement between the solid particles or protrusions and the object, the damage caused by the migration of the surface material of the object is caused.
3.2
Wear-resistant parts
Equipment parts made of wear-resistant materials.
3.3
Broken rate of grinding ball
The percentage of the number of grinding balls whose crushed area exceeds 1/3 of a single grinding ball to the total number of balls.
3.4
Out-of-roundness of grinding ball
The chord height of the missing part of the grinding ball exceeds a quarter of the diameter of the grinding ball as an out-of-round.
3.5
Out-of-roundness rate of grinding ball
The percentage of the weight of the out-of-round grinding ball to the total weight of the grinding ball.
4 Technical requirements
4.1 Production method
The ball mill balls and liners specified in this part can be selected by the manufacturer by suitable melting, casting, composite casting, forging (rolling), liquid
Forging, heat treatment, surface hardening and other methods are used for production, and it can also be produced according to the method agreed between the supplier and the buyer. The produced ball mill
Balls and liners should ensure their performance requirements.
4.2 Surface quality
4.2.1 The surface of cast wear-resistant parts should be flat, gates, risers, flashing burrs, fleshy, sticky sand should be cleaned up, and no cracks or gas should be allowed.
Casting defects such as holes, shrinkage holes, slag inclusions, sand inclusions, blisters, lack of meat, porosity, and cold separation affect the use.
4.2.2 Forging (rolling) wear parts should not have cracks, lack of meat, overburning, flash, folding, burrs, etc. that affect the performance of the forging (rolling)
defect.
4.2.3 The base alloy material of the composite fusion cast wear-resistant parts and the anti-wear hard metal of the working surface should be metallurgically combined, and there should be no composite casting defects such as cold barriers.
4.2.4 The surface roughness of cast wear-resistant parts should conform to the requirements of the drawing or order contract. If there is no stipulation in the drawing or order contract, its table
The surface roughness should meet the requirements of Ra25～Ra50 in GB/T 6060.1; in special cases, the specific index shall be negotiated by the supplier and the buyer.
4.3 Internal quality
The internal quality of the wear parts should conform to the drawing and technical requirements of the buyer.
4.4 Dimensional tolerance
4.4.1 The specifications and diameter tolerances of the balls of the ball mill should meet the requirements in Table 1.
Table 1 The specifications and diameter tolerance of the ball mill ball mill. mm
4.4.2 The dimensional tolerances of the cast liner shall comply with the specifications in the drawing or purchase contract. If there is no stipulation in the drawing or the order contract,
The dimensional tolerances of high manganese steel castings should meet the requirements of GB/T 5680; the dimensional tolerances of castings of other materials should meet the CT requirements of GB/T 6414
9~CT10 level regulations; under special circumstances, the specific indicators shall be negotiated by both parties.
4.5 Weight tolerance
The weight tolerances of cast wear-resistant parts and forged (rolled) wear-resistant parts shall conform to the specifications of the drawings or the order contract. If the drawing or order contract
There is no stipulation in this document, and its weight tolerance should meet the regulations of MT9～MT10 in GB/T 11351; under special circumstances, the specific indicators are determined by supply and demand.
Party agreed.
4.6 Geometric tolerance
The shape and position tolerances of the bolt holes of the casting liner shall conform to the specifications of the drawing or order contract. If there are no rules in the drawing or the order contract
The shape and position tolerances should comply with the requirements of L-level in Table 1 to Table 4 of GB/T 1184; in special cases, the specific indicators shall be negotiated by the supplier and the buyer.
4.7 Chemical composition and mechanical properties
4.7.1 The chemical composition and hardness of the grinding ball
4.7.1.1 See Table 2 for the chemical composition and hardness of cast grinding balls.
4.7.1.2 See Table 3 for the chemical composition and hardness of forged (rolling) grinding balls.
4.7.1.3 Ball crushing rate
The crushing rate of forging (rolling) grinding balls should be less than or equal to 0.5%, and the crushing of casting grinding balls ZQCr26, ZQCr20, ZQCr15, ZQCr12
The rate should be less than or equal to 1%, and the crushing rate of other grades of cast grinding balls should be less than or equal to 2%. In special cases, the specific indicators are negotiated by both the supplier and the buyer.
set.
Refer to Appendix A for the determination and calculation method of grinding ball breaking rate.
4.7.1.4 Impact fatigue life of the grinding ball
When the impact fatigue failure of the grinding ball falling ball method, the number of impacts withstanding should not be less than 8 000; in special circumstances, the specific indicators are negotiated by both parties
set.
See Appendix B for the test method of impact fatigue life of the grinding ball.
4.7.1.5 Ball consumption of grinding ball
The ball consumption per ton of coal grinding balls should be less than or equal to 60 grams. In special circumstances, the specific indicators shall be negotiated by the supply and demand parties.
Refer to Appendix C for the calculation method of ball consumption of grinding balls.
4.7.1.6 Out-of-round rate of the grinding ball
The out-of-roundness rate of the grinding ball should be less than or equal to 3%; in special circumstances, the specific index shall be negotiated by the supplier and the buyer.
See Appendix D for the calculation method of the out-of-round rate of the grinding ball.
4.7.2 The chemical composition and mechanical properties of the liner
The chemical composition and mechanical properties of the liner are shown in Table 4.
4.8 Metallographic organization
4.8.1 The metallographic structure of ZGM120Mn13, ZGM120Mn13VTi, ZGM120Mn13Cr2, ZGM120Mn18Cr2 shall comply with GB/T
5680 and GB/T 13925.
4.8.2 Refer to Appendix E for the metallographic structure and service characteristics of the grinding ball and liner.
5 Test method
5.1 The surface quality should be visually inspected; if necessary, a combination of inspection tools, gauge blocks, templates and markings with corresponding accuracy can be selected
Method to proceed.
5.2 For the parts that are prone to defects in the grinding ball and the liner, and the parts that are in doubt by visual inspection, the manufacturer should adopt non-destructive testing methods.
Test; non-destructive testing shall be carried out according to the methods specified in GB/T 5677, GB/T 6402, GB/T 7233.1, GB/T 9443, GB/T 9444,
It can also be carried out according to the testing method agreed by the supplier and the buyer.
5.3 Non-destructive testing shall be carried out on the factory liner at a rate of 20%. In special cases, the specific testing rate shall be negotiated between the supplier and the buyer.
5.4 The dimensional tolerances should be carried out with corresponding testing tools and instruments, and should meet the requirements of GB/T 6414.
5.5 The analysis method of chemical composition can be in accordance with GB/T 223.4, GB/T 223.5, GB/T 223.11, GB/T 223.18, GB/T 223.23, GB/T
223.25, GB/T 223.26, GB/T 223.43, GB/T 223.59, GB/T 223.60, GB/T 223.63, GB/T 223.64, GB/T 223.67,
GB/T 223.68, GB/T 223.69, GB/T 223.71, GB/T 223.72, or in accordance with GB/T 4336, GB/T 14203
The preparation of chemical composition analysis samples should meet the requirements of GB/T.20066.
5.6 The tensile test shall be carried out in accordance with the provisions of GB/T 228.1.
5.7 The impact test shall be carried out in accordance with the provisions of GB/T 229.
5.8 Rockwell hardness test shall be carried out in accordance with GB/T 230.1, GB/T 230.2, GB/T 230.3, and Brinell hardness test shall be carried out in accordance with GB/T 231.1
The regulations are carried out. The hardness test of the wear-resistant part body and the working surface of the composite fused-cast wear-resistant part can be tested and replaced with a portable hardness tester.
Calculated as Rockwell hardness HRC (or Brinell hardness HBW) control reference; when using a portable hardness tester, you should use the calibrated standard hardness
To verify the hardness of the test block, the hardness test surface should be removed from the oxidation decarburization layer and subjected to the necessary grinding and polishing treatment.
Refer to Appendix F for the approximate conversion value relationship table between Brinell hardness and Rockwell hardness.
5.9 The metallographic test method of austenitic high manganese steel series material grades shall be carried out in accordance with the provisions of GB/T 13925.The metallographic structure of other material grades
The organization test method is carried out in accordance with the provisions of GB/T 13298.
6 Inspection rules
6.1 Internal and external quality inspection
6.1.1 The surface quality of wear-resistant parts should be visually inspected 100% piece by piece.
6.1.2 If there is any doubt about the internal quality of wear parts, non-destructive testing should be carried out; if necessary, an autopsy should be carried out for metallographic examination.
6.2 Dimensional accuracy inspection
The grinding balls shall be randomly inspected according to the provisions of GB/T 2828.1, and the liner shall be inspected piece by piece.
6.3 Chemical composition inspection
The chemical composition inspection is carried out by heat (pieces, batches).
6.4 Mechanical performance inspection
6.4.1 The tensile inspection of austenitic high manganese steel wear parts shall be carried out in accordance with the provisions of GB/T 5680.
6.4.2 The impact absorption energy inspection shall be carried out by randomly selecting the product or body test block from each batch of products and processing 3 samples, and one of them is allowed to be tested.
Such impact value is lower than the specified value, but should not be less than 70% of the specified lower limit. If it is unqualified, you can extract products from the same batch or
Three samples are processed on the main test block for re-inspection, and the re-inspection results are added to the original results to recalculate the average value; if the new average value cannot meet the requirements
If any one of the requirements or retest values is lower than 70% of the specified lower limit, the batch of products is unqualified. Specimen specifications of shock absorption energy and
The sampling method should meet the following requirements.
a) The impact sample size of austenitic high manganese steel and wear-resistant parts with clear requirements is 10mm×10mm×55mm, U-shaped notch (notch
The depth is 2mm); Refined casting, liquid die forging ZGM50SiCrNiMo liner impact sample size is 10mm×10mm×55mm, V
Shape notch (notch depth is 2mm); the impact sample size of other wear-resistant parts is 10mm×10mm×55mm without notch.
b) The impact samples of the wear-resistant parts products can be prepared from the product, or from the test block cast in the same furnace with the workpiece, and
Heat treatment in the same furnace (or the same process) as the workpiece.
6.4.3 The hardness test can be carried out on the working surface of the wear-resistant part body or on the attached casting test block of the wear-resistant part body.
Before the required heat treatment, the attached test block cannot be separated from the body of the wear part. At least 3 pieces of each batch of products are randomly selected for inspection;
The hardness test parts of the product should not be less than 3, and each part should be tested at 5 points, whichever is the average value; the arbitration hardness value should be carried out by a desktop hardness tester
test.
6.5 Metallographic inspection
Austenitic high manganese steel should be subjected to metallographic inspection, and other wear parts should be subjected to metallographic inspection when materials and processes change or users require
Phase organization inspection. The metallographic test specimens can be made on the body of the wear-resistant part, or can be subjected to the impact test under the same heat treatment process with the casting
Sample preparation...
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