What is KmTBCr28?

KmTBCr28 has the main elements of Chrome 28%, low Carbon with hardness of 430 in Brinell. KmTBCr28 is a corrosion resistant white iron suitable for low pH corrosion duties, where erosive wear is also a problem.

KmTBCr28: its hardness is 430 in Brinell and suitable for corrosive applications where pH is below 4.

The bimetal wear-resistant pipe is composed of an outer wall and an inner lining. The outer wall is a seamless steel pipe with a thickness of 6-20mm, and the inner lining is a high-chromium-nickel alloy with a thickness of 12-30mm. Casting, this product makes full use of the high pressure bearing capacity, good welding performance and high hardness of high chromium-nickel alloy (HRC30-50) of seamless steel pipe. It is an ideal wear-resistant conveying pipeline.
The outer steel body of the bimetal wear-resistant pipe is made according to the design requirements. The outer arc of the inner wall of the steel needs to be welded and attached to the wear-resistant layer, so that the wear-resistant layer can be firmly attached to the inner wall of the pipe.

Chemical composition（%）of KmTBCr28

Grade	C	Si	Cr	Mo	Mn	Ni	S
KMTBCr28	3.00	1.19	8-27.00	0.25	1.20	0.45	0.06

Mechanical properties (reference value)

Grade	Tensile strength （MPa）	Impact toughness （J/cm）	Bending strength （MPa）	Hardness (HRC)	Rate of reduction in area （%）	Hydrostatic test pressure （MPa）
KMTBCr28	550	18	610	46-56	1	1.5

Features

KMTBCr28 bimetal wear-resistant elbow has increasingly become a more reliable anti-wear solution for material conveying systems in industries such as electric power, steel, chemical industry, and smelting because of its good wear resistance and reliable welding performance.

1. Wear resistance: hardness HRC>35, with good wear resistance and thermal stability.
2. Impact resistance The joint surface of the two metals is completely metallurgical, and the thermal expansion coefficients of the two are equivalent, and there will be no expansion and contraction cracking.
3. Heat resistance and corrosion resistance: in wet state, under the action of corrosive medium and particle scouring, it is more suitable to use the hardness alloy used in the as-cast state;
4. The product has good compactness, uniform thickness and stable quality.

Technical parameter

Model Φ76-900
Material grade KMTBCr28 (customizable)
Customized according to the picture Straight pipe, elbow, elbow, tee, reducer, etc. can be customized.

KMTBCr28 bimetallic composite wear-resistant pipe came into being and has been widely used since the late 1990s. KMTBCr28 bimetallic composite elbow can not only ensure the requirements of pipeline toughness, weldability and strength (compression resistance), but also ensure sufficient wear resistance. It is an ideal solution for wear-resistant pipelines for material transportation.

KMTBCr28 bimetallic composite elbow can not only ensure the requirements of pipeline toughness, weldability and strength (compression resistance), but also ensure sufficient wear resistance. It is an ideal solution for wear-resistant pipelines for material transportation.

Applicable industries

1. Electric power industry: raw coal system silo, hopper, funnel, powder feeding pipeline.
2. Coal industry: heavy ore coal preparation pipeline in coal preparation plant, wet coal conveying system, sediment backfill in mining.
3. Mining industry: mine filling, concentrate powder transportation, tailings transportation pipeline.
4. Iron and steel industry: coke particle conveying pipeline, coal mill pipeline, separator, elbow, cone, separation baffle.
5. Cement industry: coal powder transportation, mineral powder transportation.
6. Machinery industry: lining of power plant pulverizing, dust removal and ash discharge system equipment, lining of steel mill dust removal equipment.

Metal Slurry Pump Wear Parts Material:

• KmTBCr27 is named in China, which has 27% Chrome. Alloy KmTBCr27 is a wear resistant white iron that offers excellent performance under erosive conditions.
• KmTBCr28 has the main elements of Chrome 28%, low Carbon with hardness of 430 in Brinell. KmTBCr28 is a corrosion resistant white iron suitable for low pH corrosion duties, where erosive wear is also a problem.
• KmTBCr35 has the main elements of Chrome 35-45%, low Carbon with hardness of 450 in Brinell. KmTBCr35 is a premium erosion/corrosion alloy to be used where excellent erosion and corrosion resistance is required.

High Chrome Alloy Castings

• KmTBCr27 is a wear resistant white cast iron that offers excellent performance under erosive conditions. The alloy can be effectively used in a wide range of slurry types. The high wear resistance of KmTBCr27 alloy is provided by the presence of hard carbides in the microstructure. KmTBCr27 Alloy is particularly suited to mild acidic duties where erosion resistance is required.
• KmTBCr28 is martensitic white iron with moderate erosion resistance.It has the main elements of Chrome 28%, low Carbon with hardness of 430 in Brinell, KmTBCr28 is a corrosion resistant white iron suitable for low PH corrosion duties, where erosive wear is also a problem.
• KmTBCr35 is a premium erosion/corrosion alloy, The main elements of Chrome is 35-45%, low Carbon with hardness of 450 in Brinell. KmTBCr35 Alloy is suitable for phosphoric acid duties, FGD duties, sulphuric acid , and other moderately corrosive applications.

Chemical composition and grade of high chromium cast iron (bimetallic)

The old brand name of the national standard starts with KmTB, and the new brand name starts with BTM.

Grade and chemical composition of high chromium cast iron:

Grade	Chemical composition(%)
	C	Si	Mn	Cr	Mo	Ni	Cu	S	P
BTMCr12-DT	1.1-2.0	≤1.5	≤2.0	11.0-14.0	≤3.0	≤2.5	≤1.2	≤0.06	≤0.06
BTMCr12-GT	2.0-3.6	≤1.5	≤2.0	11.0-14.0	≤3.0	≤2.5	≤1.2	≤0.06	≤0.06
BTMCr15	2.0-3.6	≤1.2	≤2.0	14.0-18.0	≤3.0	≤2.5	≤1.2	≤0.06	≤0.06
BTMCr20	2.0-3.3	≤1.2	≤2.0	18.0-23.0	≤3.0	≤2.5	≤1.2	≤0.06	≤0.06
BTMCr26	2.0-3.3	≤1.2	≤2.0	23.0-30.0	≤3.0	≤2.5	≤1.2	≤0.06	≤0.06

Hardness of high chromium cast iron

Grade	As-Cast or As-Cast Stress Relief		Hardened state or hardened state stress relief		Soft annealed state
	HRC	HBW	HRC	HBW	HRC	HBW
BTMCr12-DT	—	—	≥50	≥500	≤41	≤400
BTMCr12-GT	≥46	≥450	≥58	≥650	≤41	≤400
BTMCr15	≥46	≥450	≥58	≥650	≤41	≤400
BTMCr20	≥46	≥450	≥58	≥650	≤41	≤400
BTMCr26	≥46	≥450	≥58	≥650	≤41	≤400

Below are some foreign high chromium cast iron grades and standards

American ASTM A532M:1993

Chemical composition of high chromium cast iron

Grade	Chemical compositon(%)
	C	Mn	Si	Ni	Cr	Mo	Cu	P	S
12Cr	2.0-3.3	≤2.0	≤1.5	≤2.5	11.0-14.0	≤3.0	≤1.2	≤0.1	≤0.06
15Cr-Mo	2.0-3.3	≤2.0	≤1.5	≤2.5	11.0-18.0	≤3.0	≤1.2	≤0.1	≤0.06
25Cr-Mo	2.0-3.3	≤2.0	≤1.0-2.2	≤2.5	18.0-23.0	≤3.0	≤1.2	≤0.1	≤0.06
25Cr	2.0-3.3	≤2.0	≤1.5	≤2.5	23.0-30.0	≤3.0	≤1.2	≤0.1	≤0.06

Hardness of high chromium cast iron

Grade	Hardness
	Sand casting									Chill casting ≥			Annealing ≤
	As cast or as cast + stress relief annealing			Quenching or Quenching + Stress Relief Annealing
				level 1			level 2
	HBW	HRC	HV	HBW	HRC	HV	HBW	HRC	HV	HBW	HRC	HV	HBW	HRC	HV
12Cr	550	53	600	600	56	660	650	59	715	550	53	600	400	41	430
15Cr-Mo	450	46	485	600	56	660	650	59	715	–	–	–	400	41	430
25Cr-Mo	450	46	485	600	56	660	650	59	715	–	–	–	400	41	430
25Cr	450	46	485	600	56	660	650	59	715	–	–	–	400	41	430

England

Chemical composition of high chromium cast iron

Grade	Chemical composition(%)
	C	Si≤	Mn	Cr	Mo≤	Ni≤	Cu≤	P≤	S≤
3A	1.8-3.0	1.0	0.5-1.5	14-17	2.5	2.0	2.0	0.10	0.10
3B	3.0-3.6	1.0	0.5-1.5	14-17	3.0	2.0	2.0	0.10	0.10
3C	1.8-3.0	1.0	0.5-1.5	17-22	3.0	2.0	2.0	0.10	0.10
3D	2.0-2.8	1.0	0.5-1.5	22-28	1.5	2.0	2.0	0.10	0.10
3E	2.8-3.5	1.0	0.5-1.5	22-28	1.5	2.0	2.0	0.10	0.10
3F	2.0-2.7	1.0	0.5-1.5	11-13	2.5	2.0	2.0	0.10	0.10
3G	2.7-3.4	1.0	0.5-1.5	11-13	3.0	2.0	2.0	0.10	0.10

Hardness of high chromium cast iron

Grade	Cast state		Annealed state		Heat treatment state
	HBW≥	HV50≥	HBW≤	HV50≤(conversion value)	HBW≥	HV50≥
3A	450	485	400	428	600	655
3B	500	542	450	485	650	712
3C	450	485	450	485	600	655
3D	400	428	400	428	600	655
3E	450	485	450	485	600	655
3F	450	485	400	428	600	655
3G	450	485	450	485	650	712

Germany

Chemical composition of high chromium cast iron

Grade	Chemical compostion(%)
	C	Si	Mn	Cr	Ni	Mo
G-X300CrMO15-3	2.3-3.6	0.2-0.8	0.5-1.0	14-17	0.7	1.0-3.0
G-X300CrMoNi15-2-1	2.3-3.6	0.2-0.8	0.5-1.0	14-17	0.8-1.2	1.8-2.2
G-X260CrMoNI20-2-1	2.3-2.9	0.2-0.8	0.5-1.0	18-22	0.8-1.2	14-2.2
G-X260Cr27	2.3-2.9	0.5-1.5	0.5-1.0	24-28	1.2	1.0
G-X300CrMo27-1	3.0-3.5	0.2-1.0	0.5-1.0	23-28	1.2	1.0-2.0