Versatile alloys and seamless tubes

Ovako's extensive knowledge and expertise in developing low alloy boron steel means it now has 37 different material grades of the material in its melt programme.

All of these, when heat treated, can achieve properties comparable with those of considerably higher alloy steels, making them significantly more economical. 

Developing specific grades of boron steel requires advanced steelmaking techniques which the metal producer has developed as part of its substantial boron steels programme. In order to produce this only small additions of boron are required which, in combination with carbon and other alloying elements, increases the hardenability of the steel.

The company first developed the material back in the 1960s. The process has to ensure that the boron within the steel melt remains protected by the alloying elements to prevent it from reacting with the oxygen and nitrogen in the steel. This gives the materials its exceptional capabilities.

Cold formability of boron steel grades in ‘as rolled' condition is very good so no annealing is required. This can be a significant advantage when the steel is to be used in cold forming or blanking processes.

As an alloying element the boron has no direct effect on the machinability of the steel, it being comparable with the machinability of Cr Mo steels of the same hardness. Like other low alloy steels, boron steels subjected to extensive machining may benefit from the addition of sulphur.

Hardening and tempering makes it possible to obtain considerably higher strength levels in the boron steel grades compared to other structural steels of considerably higher alloy content.

Typically, the mechanical properties of a popular Ovako boron steel grade bar, between 25mm – 40mm diameter after hardening and tempering at 500°C, produces a yield strength of 750 Rs N/mm², tensile strength of 900 – 1050 Rm N/mm² and a hardness of 275 – 32 HB.

The material is used in a comprehensive range of applications, such as agricultural machinery, automotive components, wind turbines, bearings, fixing bolts, lifting hooks, crusher hammers, concrete manufacture, transport chains, wood and paper production and cane sugar manufacture.

Ovako's product range also includes sizes of round bar, flat bar and rolled billets and the company is helping to bring down component costs for customers in the automotive and engineering sectors by supplying seamless tubes to very fine tolerances directly from the mill.

As a leading producer of hot rolled and cold worked seamless tubes it has invested heavily in plant and procedures to enable it to manufacture high quality tube to guaranteed dimensions, so customers are able to reduce machining, improve yields and cut costs.
Ovako has achieved this by controlling the production process from steel melt to finished tube. The starting point is the production of high quality steel with consistently low levels of oxygen. Modern precision rolling techniques are used to convert the steel into a wide range of hot rolled, cold rolled or cold drawn seamless tubes as well as hot rolled peeled tubes and cold rolled or drawn centreless ground tubes.

Already one of the world's largest manufacturers of seamless tubes for the bearing industry, Ovako's stock programme for bearing grade steels covers 350 tube sizes from OD 30mm to 250mm. Carbon hollow bar (EN10294) is stocked in 250 sizes in the same diameter range.

Wall thicknesses range from 3mm to 50mm. The wide range of standard sizes means that customers can quickly achieve a close match to their stock requirements. The tube is supplied either in random lengths or to fixed lengths up to 6m.

Ovako
www.ovako.com

Related Articles

The full package

A stock of more than 16,000 standard stainless steel items at the Sandvik distribution centre in Halesowen, West Midlands, helps service on-demand and scheduled supply requirements
9 years ago Features

The cold facts

By cold forming aluminium manufacturers can significantly cut costs and reduce waste while maintaining or even enhancing the material properties, says Mark Jennings, technical director at Dawson Shanahan.
11 years ago Features
Most recent Articles

Renishaw highlights career pathways in engineering

There is not one singular blueprint that can lead to a career in the engineering industry. It offers a variety of roles, open to people from diverse backgrounds. To highlight the diversity of skills and experiences in engineering, global engineering technologies company, Renishaw, has created the ‘Employee perspectives’ series.
22 hours ago News

Login / Sign up