This standard applies to medium manganese wear-resistant ductile iron castings with a metal matrix structure dominated by martensite and austenite. GB/T 3180-1982 Technical conditions for medium manganese wear-resistant ductile iron castings GB/T3180-1982 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Technical conditions for medium manganese wear-- resistant spheroidal iron castings
Specification for medium manganese wear-- resistant spheroidal iron castings This standard is applicable to medium manganese wear-- resistant spheroidal iron castings with the metal matrix structure mainly composed of spheroidal graphite. UDC 669.131.7
GB 3180--82
Metallurgical structure of medium manganese wear-resistant ball cast iron refers to JB/7179-82 "Metallurgical Atlas of Medium Manganese Anti-friction Ball Cast Iron" 1. Grade
Medium manganese anti-friction ball cast iron parts are divided into three grades according to their manganese content and mechanical properties. They are listed in the following table. Hangwan StrengthWww.bzxZ.net
MQTMn6
MQTMn7
MQTMn8
5.5 ~ 6.5
.7.5~9.0
kgi/ mm(
(N/mrn2)
Test rod diameter
52(510)
48(471)
44（432）
Metal mold
40（392）
45(441）
50(491）
Metal mold
0.8(7.85)
0.9(8.83)
1.0(9.81)
1.2“M” is anti-wear and “磨” is the first letter of the Chinese pinyin. The brand “QT” is “ductile iron” The first "Mn" in Pinyin is the chemical symbol of manganese, and the Arabic numerals indicate the range of manganese content. 2 Technical requirements
2.1 The quality inspection of metal mold castings shall be based on the impact value and hardness of the sand mold casting specimen and the flexural strength of the metal mold casting iron bending test bar as the acceptance basis. The quality inspection of sand mold castings shall be based on the impact value and hardness as the acceptance basis, and the results shall conform to the table specifications.
The maximum manganese content in the table, the toughness, deflection and the flexural strength of the sand mold casting 30 mm diameter flexural test bar shall not be used as the acceptance basis unless otherwise specified in the order agreement.
If the user requires the casting hardness to be inspected, it shall be checked with the production According to the negotiation between the manufacturer and the manufacturer, the hardness value shall conform to the provisions in the table. 2.2 The geometric shape, dimensional tolerance and weight deviation of the casting shall conform to the provisions of JIB2854--80 "Mechanical allowances, dimensional tolerances and weight deviations of cast iron parts" or the order agreement. 2.3 The molding sand and core sand on the casting shall be eliminated, and the pouring gate, riser, excess meat, scars, sand adhesion, sand inclusions, etc. shall be removed. 3 Test methods and inspection rules
3.1 In single-piece and small-batch production, at least one set of test samples shall be taken from each bag of molten iron. In batch and large-scale production, under the condition that the raw materials and production process are stable, each heat of molten iron shall be inspected at least three times. National Bureau of Standards 1982-0901 Published
1983-0701 Practice
GB3180—82
3.2 Four impact test pieces are cast in the impact test box, as shown in Figure 1, and one is selected for impact test. The impact test method is carried out in accordance with GB229-63 "Metal Normal Temperature Impact Toughness Test Method", and the impact test block specifications are shown in Figure 2, with a branch jump of 70 meters. Total V
Figure 1 Impact test piece (mold)
Note: The size deviation of the casting test block is ±1.0 mm. Figure 2 Impact test block
3.3 The determination of hardness value is to grind the cross section of the three impact test blocks that have been tested, measure three points at 5 mm from the center, and take the average value. The hardness test is carried out in accordance with GB230-63 "Metal Rockwell Hardness Test Method". 3.4 The production of bending test specimens should be cast with molten iron. The production of metal mold bending test specimens is shown in Figure 3. The depth of the mold should be GB3180--82
min F2 mm. The test bar specifications are shown in Figure 4. The bending test method is carried out in accordance with GB977-67 "Mechanical Properties Test Methods for Gray Iron Castings".
中50±0.1
中了0
Figure 3 Metal mold (mold) of bending test specimen
All 2
Note: The allowable deviation of the test bar diameter is +1.4 mm; the shortest length is 540 mm:
The maximum and minimum true diameters are allowed to deviate by 1.5 mm. Figure 4 Bending test bar
Additional instructions:
GB3180-82
This standard was proposed by the Ministry of Machinery Industry, and the Shenyang Foundry Research Institute of the Ministry of Oil Machinery Industry called the door. This standard was drafted by the Mining Bureau of the Ministry of Metallurgy, the Shenyang Foundry Research Institute of the Ministry of Machinery Industry and other units. The main drafters of this standard are: Sun Liwei, Zhai Chunfang, Zhang Xiaokong, Li Banghuang, Liu Hongzhi, Gai Xing, Shi Weian, Ling Jisheng, etc. This standard was first issued on September 1, 1982.
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.