CN1060535C

CN1060535C - Iron based, rare earth containing, low chromium content antiwear alloy steel

Info

Publication number: CN1060535C
Application number: CN97105722A
Authority: CN
Inventors: 王执福; 张典华
Original assignee: DONGFANG SPECIFIC STEEL WORKS SHANDONG PROV; Shandong Polytechnic University
Current assignee: DONGFANG SPECIFIC STEEL WORKS SHANDONG PROV; Shandong Polytechnic University
Priority date: 1997-03-19
Filing date: 1997-03-19
Publication date: 2001-01-10
Anticipated expiration: 2017-03-19
Also published as: CN1193663A

Abstract

The present invention relates to iron-based antiwear alloy steel with rare earth and low chromium, which belongs to heat-resistant antiwear steel materials. The iron-based antiwear alloy steel is mainly used as a manufacturing material for the powdered coal pipes of coal-fired boilers in thermal power plants. The iron-based antiwear alloy steel is formed by the way that iron-based alloy steel with low chromium is added to rare earth ferrosilicon according to weight portion ratio of 1: 0.05 to 0.10 in a melting state. The iron-based antiwear alloy steel has excellent heat-resistant and antiwear performance and welding performance, and satisfies the using requirements and installing process requirements of the powdered coal pipes. As compared with powdered coal pipes manufactured by carbon steel or interlayer cast stone pipes, the powdered coal pipes manufactured by the iron-based antiwear alloy steel have good properties, and prolong the service life by more than ten times. The iron-based antiwear alloy steel can generate obvious social and economic benefits by wide popularization and use.

Description

Iron based, rare earth containing, low chromium content antiwear alloy steel

The invention belongs to heat-resisting Development of Wear Resistant Steel material, be mainly used in the manufacturing of coal pipe of thermal power plant's coal firing boiler.

The power plants coal firing boiler is a fuel with the coal dust that the mixing coal grinds; and be mixed with very hard particles such as a lot of quartz in the coal dust; thereby the subtend boiler carries the pulverized coal channel of this coal dust to produce serious wearing and tearing; and the coal pipe that materials such as original used carbon steel are manufactured does not have good wear resistance; cause work-ing life shorter, because the coal pipe leakage that is worn through, contaminate environment but also sizable danger is arranged not only; necessary shutdown maintenance has a strong impact on power benefit.Therefore improve the material of coal pipe, improve its heat-resisting resistance to abrasion,, become the important topic that scientific worker and a lot of thermal power plant research and solve to improve its work-ing life.So developing in succession, people release some heat-resisting anti-friction alloy materials, they are applied to coal pipe, though can improve heat-resisting resistance to abrasion, because of pulverized coal channel is made up of the bend pipe of straight tube and different angles, for guaranteeing the resistance to air loss of pipeline, during pipe laying, all be, and crack during the welding that the coal pipe of above-mentioned material has the coal pipe welding assembly, be that the weldability difference can't be used, though the weldability that has is good, its hardness is not enough, so still should not adopt.Once once adopting interlayer cast stone pipeline both at home and abroad, it promptly the carbon steel layer, the centre is the cast stone layer, but its mechanical collision when being afraid of carrying and installation easily causes cast stone slabbing line, two because of internal layer be that the carbon steel layer easily is worn down to the thin slice turnup and blocks and mix coal-fired powder air-flow, cause circulation not smooth, this moment, the operator beat a little that then the cast stone layer is cracked, promptly was worn through, so also can't resolve above-mentioned root problem.

Purpose of the present invention is to solve the deficiency of above-mentioned coal pipe material therefor, provides a kind of and has not only had heat-resisting resistance to abrasion but also had good weldability, is applicable to material---the iron-based rare-earth low chrome steel of coal pipe.

Technical scheme of the present invention is, when iron-based low chrome steel is heated to melted state, weight percent by 0.05～0.10% adds rare earth ferrosilicon alloy and forms, the chemical constitution (weight percent) of this iron-based low chrome steel is: C 0.30～0.55%, Si 0.40～1.00%, Mn 0.60～1.40%, Ni 0.30～2.20%, Cr 0.80～5.00%, Mo0.30～0.60%, V 0.06～0.20%, and RE 0.05～0.10%, S and P all≤0.03%, all the other are Fe and impurity.

Below in conjunction with embodiment the present invention is done following further specifying,, be advisable with the packet header 1# rare earth ferrosilicon alloy that adopts packet header steel mill about the rare earth ferrosilicon alloy material that adds in the technical solution of the present invention.Iron-based low chrome steel of the present invention, according to the difference of making wide-angle bend pipe or Small angle and straight tube coal pipe, should select following two kinds of chemical constitutions (all being weight percentage) respectively for use:

One .C 0.40～0.55%, Si 0.40～0.80%, and Mn 0.60～1.20%, and Ni 1.00～2.20%, Cr 3.50～5.00%, and Mo 0.30～0.60%, and V 0.06～0.20%, RE 0.05～0.10%, S and P all≤0.03%, all the other are Fe and impurity.

Two .C 0.30～0.48%, Si 0.40～1.00%, and Mn 0.80～1.40%, and Ni 0.30～1.80%, Cr 0.80～2.50%, and Mo 0.30～0.60%, and V 0.06～0.20%, RE 0.05～0.10%, S and P all≤0.03%, all the other are Fe and impurity.

According to technique scheme, the wide-angle bend pipe of making, its hardness of cast form HRC＞45 are usually about HRC55.Hardness of cast form HRC＞40 of Small angle and straight tube, usually about HRC45, improve its hardness by adjusting after the thermal treatment, the coal pipe of this material had both solved heat-resisting resistance to abrasion, have again good can brave property, satisfied the service requirements and the installation technology requirement of thermal power plant's coal pipe preferably, through on probation, demonstrate bigger superiority, estimate to improve more than 10 times work-ing life, so can extensively promote the use of than the carbon steel pipe of former usefulness.

Claims

1, a kind of iron based, rare earth containing, low chromium content antiwear alloy steel, it is characterized in that its chemical element composition (weight percent) is: C 0.30～0.55%, Si 0.40～1.00%, and Mn 0.60～1.40%, and Ni O.30～2.20%, Cr 0.80～5.00%, Mo 0.30～0.60%, and V 0.06～0.20%, and RE 0.05～0.10%, S and P all≤0.03%, all the other are Fe and impurity.

2, iron based, rare earth containing, low chromium content antiwear alloy steel as claimed in claim 1, it is characterized in that its chemical element composition (weight percent) is: C 0.40～0.55%, Si 0.40～0.80%, and Mn 0.60～1.20%, and Ni 1.00～2.20%, Cr 3.50～5.00%, Mo 0.30～0.60%, and V 0.06～0.20%, and RE 0.05～0.10%, S and P all≤0.03%, all the other are Fe and impurity.

3, iron based, rare earth containing, low chromium content antiwear alloy steel as claimed in claim 1, it is characterized in that its chemical element composition (weight percent) is: C 0.30～0.48%, Si 0.40～1.00%, and Mn 0.80～1.40%, and Ni 0.30～1.80%, Cr 0.80～2.50%, Mo 0.30～0.60%, and V 0.06～0.20%, RE 0.05～0.1 0%, S and P all≤0.03%, all the other are Fe and impurity.