What is high chromium steel?

High chromium steel, often referred to as high chrome steel or high chromium white iron, is a type of alloy steel that contains a high concentration of chromium. This alloy steel is characterized by its excellent wear resistance and corrosion resistance properties, primarily due to the high chromium content.

High chromium steel is commonly used in applications where abrasion and wear resistance are critical, such as in mining, mineral processing, and the manufacturing of cement, among others. The high chromium content in this steel promotes the formation of hard chromium carbides within the microstructure, which enhances its resistance to wear, impact, and corrosion.

This type of steel can be used to manufacture components like crusher hammers, liners for ball mills and grinding mills, excavator buckets, and various other parts subject to severe abrasion and impact.

Different grades of high chromium steel exist, such as ASTM A532 and ASTM A532M, which provide guidelines and specifications for high chromium white iron castings used in wear-resistant applications. The specific chemical composition and properties may vary based on the intended application and manufacturer.

Technical requirements

• The overall performance of the bimetal wear-resistant composite elbow must meet the following requirements; the flexural strength must be greater than 610MN/M2, the tensile strength must be greater than 415MN/M2, the impact toughness must be greater than 15J/CM2, and the hardness of the wear-resistant layer must be greater than 50.
• The inner and outer surfaces of the bimetal wear-resistant composite elbow should be smooth and clean, without burrs, burrs, cracks, porosity, pores or air bubbles, no cracks are allowed, the pipe has good compactness, and the flow direction of the medium should be marked in obvious parts. The inner lining of each elbow must be formed at one time, and it is strictly prohibited to weld the folded line after it is produced in sections.
• The dimensional deviation of pipe fittings shall comply with the provisions of GB3092, GB8162 and GB8163, and shall comply with the requirements of product drawings and order agreements. Thickness deviation of inner lining ≤+1.2mm. The weight of each elbow cannot exceed the design weight. And mark the weight in the obvious place.
• The steel pipe used in the composite pipe adopts seamless steel pipe, and its performance shall comply with the relevant agreement.
• The bimetal wear-resistant composite elbow is installed by direct welding, with good welding performance, and the outer welded pipe is made of 16MnR# steel.
• Each inlet and outlet of the bimetal wear-resistant composite elbow has a straight section of a certain length. The straight section (L1/L2) should be consistent with the material and wall thickness of the elbow body, and a 100mm transition section is added outside the straight section to be welded to the powder feeding pipeline. There should be no special requirements for on-site welding of products to ensure good welding performance when products are welded at room temperature on site.
• The life of the bimetal wear-resistant composite elbow is not less than 10 years (8000 hours of operation per year).
• During the service life of the bimetal wear-resistant composite elbow and under the abnormal conditions of spontaneous combustion of the powder feeding pipeline, the product should ensure that the lining wear-resistant layer does not crack or peel off; when the pipeline is partially blocked, it should ensure that it can knock, cutting, it should be convenient for unloading, installation and maintenance.
• The sealing performance test of the bimetal wear-resistant composite elbow shall be carried out before leaving the factory, and the test shall be carried out according to the relevant standards. When the quality and performance of the products provided by the supplier do not meet the specified standards, they shall not leave the factory.
• The product should meet the “DL/T 680-1999 Technical Conditions Standard for Wear-Resistant Pipelines”.

Technical requirements parameter table

Special Corundum ceramics made of rare metal oxides as solvents and sintered at high temperature by 1730 ℃ through bonding, welding, mosaic, riveting and socket technology, a variety of wear-resistant ceramic pieces, block brick materials in the pipe wear surface, so as to form a surface with excellent wear resistance, and the matrix is still using the composite pipe of ordinary metal.

Main technical parameters of bimetal composite wear-resistant elbow:

• Thickness of bimetal wear-resistant composite elbow: inner arc: 22 outer arc: 32
• Eccentricity: 5mm
• Thickness deviation of inner lining: ≤+1.2mm
• Design pressure: 1.6Mpa, hydraulic test pressure: 5.6-19MPa:
• Design temperature: 350℃

Chrome-Moly

• Chromium-Molybdenum Alloy Steel or Chrome-Moly, CrMo is an alloy steel intended for high temperature and high pressure services.
• Chrome-Moly is used in the power generation industry and the petro-chemical industry because of its tensile strength, corrosion resistance and high-temperature strength.
• Chrome-Moly has a better strength to Weight ratio than steel, which enables designers to use thinner wall pipe or smaller diameter tubing to reduce overall weight.
• Chromium-Molybdenum Alloy Steel has strong resistance to rupturing at high temperatures and high pressures.
• Chrome-Moly is also resistant to cracking from hydrogen attack and hot sulfide corrosion cracking.
• Chrome-Moly grades P-11, P-22, P-91 and P-92 are used in the power industry.
• Chrome-Moly grades P-5 and P-9 are used in petro-chemical refinery processes.
• Chrome-Moly Forged Fittings & Flanges are available in grades F-5, F-9, F-11, F-22, F-91, F92.
• Chrome-Moly Alloy Butt Weld Fittings are available in grades WP-5, WP-9, WP-11, WP-22, SP-91, WP-92.
• F11 and F22 meet NACE-MRO 175.

Bimetal wear resistant products including: double metal wear-resisting straight pipe and double metal wear-resisting bend, double metal wear tee, double metal wear resistance reducer adopts the pipe fittings such as vacuum suction casting composite process, its advanced technology, effectively solve the problem of the bent pipe cannot be composite, bending and other various special-shaped pipe can do the whole compound, don’t change the material flow in the pipe bending trajectory, reduce resistance material conveying.

The outer wall of the centrifugal pipe is made of carbon steel, which ensures that the bimetal wear-resistant pipe has high mechanical strength and impact resistance.The inner lining wear resistance layer adopts the anti-wear alloy steel series independently developed by our company. The steel mainly adds alloy such as cr-ni-mo-cu-re and so on. Through the tempering heat treatment process, the alloy steel has strong wear resistance and corrosion resistance, high mechanical strength and impact resistance.

The whole set of process of our factory is the first in China, which fills the blank of anti-corrosion and wear-resistant industrial pipeline in China and has reached the international advanced level. It has been widely used in mining, metallurgy, coal, electric power and other industries, and is an ideal wear-resistant pipeline.

Technical requirements parameter table

Special Corundum ceramics made of rare metal oxides as solvents and sintered at high temperature by 1730 ℃ through bonding, welding, mosaic, riveting and socket technology, a variety of wear-resistant ceramic pieces, block brick materials in the pipe wear surface, so as to form a surface with excellent wear resistance, and the matrix is still using the composite pipe of ordinary metal.

Main technical parameters of bimetal composite wear-resistant elbow:

• Thickness of bimetal wear-resistant composite elbow: inner arc: 22 outer arc: 32
• Eccentricity: 5mm
• Thickness deviation of inner lining: ≤+1.2mm
• Design pressure: 1.6Mpa, hydraulic test pressure: 5.6-19MPa:
• Design temperature: 350℃