While steel mills are sometimes considered to be “old-style” manufacturing, there are many examples where some of the latest motion control technologies are being used for new mills as well as retrofits. Steel mills represent an interesting challenge as advanced technologies must be used in demanding environments. These environments include exposure to extensive heat, dirt and the rigors of a 24/7 operation. Moog has long been a leader in providing Servo and Servo-Proportional Valves to most of the world’s well-known steel mills. This article focuses on some of our newest solutions for special applications in the booming China market and an innovative retrofit project in India.
Steel Production in China
There is no doubt that China is the largest steel production source in the world. In 2006, the total crude steel production in China was 418 Million tons, that’s more than 1/3 of the steel production in the world. The total investment in the heavy industry market is about 212.88 Bil RMB (26.95 Bil US$). In the past 10 years, the overall technology of the steel industry in China has greatly improved. The product structure has been constantly optimized and international competitiveness has been enhanced. Looking into 2007, analysis of both domestic and international demand suggests that steel production will increase another 10%.
Some exciting developments currently impacting the steel industry in China include:
- Shougang Group, a steel giant based in the Chinese capital of Beijing, will complete its massive relocation to Tangshan, Hebei Province by the end of 2010.
- Shanghai Baoshan Iron and Steel Corp (Baosteel) has built a new steel factory in the southern city of Zhanjiang.
- Wuhan Iron and Steel Corp has built a modern iron and steel works in Fangchenggang, also in southern China.
- Angang Steel Co. has started its new plants in Yingkou in northeastern China.
In such an exciting environment, Moog can provide proven products and new solutions based on years of experience in the market. The following two examples are applications where Moog in China recently offered solutions.
Pipe Cutting Machine – Cutter Feeding System
A large steel maker in China is building a pipe mill production line and needed a specialized pipe cutting machine. The steel pipe’s diameter can be larger than 220 mm (8.66 in) and has several different sizes. The most challenging requirement is that the pipe can be as long as 20 m (65 feet) after milling. It varies from a normal lathe machine as a jig clamps and turns the pipe and a cutter then feeds into the pipe to cut it.
To meet these requirements, Xi’an Heavy Machinery Research Institute designed a pipe cutting machine which features a long holder table to fix the long pipe, and a complex revolving cutting head turning around the pipe. The cutter is mounted on the turning head and a servoactuator controls the cutter’s precision cut into the pipe using a cam system. Considering the tolerance of the pipe during the cutting process and the extreme speed of the operation control of the cutter, feed position and speed are vital for quality and for preventing damage to both the pipe and the cutter itself.
Moog in China cooperated with Xi’an Heavy Machinery Research Institute by supplying the servoactuator, the M3000 Servocontroller System and the Moog Axis Control Software (MACS). As the cam for feeding the cutter is a non-linear system, and in order to get better cutting quality and higher cyclic efficiency, the actuator needed to follow a customized special position and velocity curve very accurately. For example, the cutter should touch the pipe softly in the beginning and keep a constant speed during cutting. This new system is currently being commissioned at the customer’s site.
CISDI Engineering Co., Ltd - AGC Actuator Test
About 10 years ago, some local Chinese OEMs started to manufacture rolling mill equipment including large size, highly dynamic and accurate AGC actuators. Recently, many OEMs began to take a system approach to dynamic performance. In the past, performance was normally evaluated on parameters such as friction, force, smoothness, speed, and pressure to understand the performance of individual components like cylinders and servovalves. For the servoactuator that was used for the full hydraulic AGC control in this high speed hot strip rolling mill system, it was necessary to understand how the servo loop works to assess the performance of the whole system, not just evaluate the performance of each individual component.
In 2005, CISDI Engineering Co., Ltd requested our help with a 1750 Hot Strip Mill Project, where approximately 100 Moog Servovalves were used in that production line to cover all servo closed-loop control functions. We helped them to design a solution for an on-site test for actuator performance by supplying a M3000 digital servocontroller and MACS control software. We cooperated with CISDI and Beijing MECC, the hydraulic system manufacturer, for the successful implementation of on-site testing.
Some key parameters the testing monitored for the actuator were position accuracy, hysteresis, step response and frequency response. The test results helped CISDI understand the whole AGC actuator system performance and enabled smoother commissioning in end user sites.
Steel Production in India
The Indian steel industry is nearly a century old with Tata Iron and Steel Co. being the first integrated steel plant set up in 1907. The industry has grown and now India is the 9th largest producer of steel in the world. The finished steel production in India has grown from a mere 1.1 million tons in 1951 to the current level of around 38 million tons. While the growth in the steel sector was formerly in the public sector units, the situation has changed dramatically in the decade from 1990-2000, with most of the growth originating in the private sector.
Currently, India has come out with a National Steel Policy with a long-term goal that India should have a modern and efficient steel industry established according to world standards and catering to a diversified steel demand. This will require indigenous production of over 100 Million Tons (MT) per annum by 2019-20.
The following example is an application where Moog in India recently offered a retrofit solution.
Mukand Ltd - Hospet Division – Billet Caster Retrofit
Another unique application recently completed by Moog in India for a local steel mill was the billet caster project with Mukand Limited also called Hospet Steel. This location has been in operation for 10 years and manufactures billet and bloom cast steel. Their present capacity is 400K Tons and they plan to increase to 1M. Tons in 3 years.
Hospet Steel had some demanding requirements for their solution that were both technical and environmental. They were seeking to improve quality by eliminating pores or blow holes and increase productivity of the billet casting by implementing an Automated Mold Level Controller (AMLC). It was also critical to upgrade from a manual to an automated system to eliminate human errors in a high production environment. An important consideration was that the solution needed to be robust and withstand an environment with dusty and humid conditions. They preferred to use local vendors with a proven track record because they needed long-term local support which included technical, repairs/spares and training services.
Moog was selected to partner with the customer based on an innovative turn-key solution approach. This included hydraulic manifold blocks and servoactuators built to suit the customer’s requirement (D633 Servovalves and the M3000 Servocontroller). Our application engineers created customer-specific software using the sample tracing capability of the MACS Software.
The AMLC project was cited by the customer as highly successful as it achieved high accuracy in maintaining control of liquid molten metal. Production cycles were improved sharply while maintaining an operation with 99% efficiency without a breakdown. Most importantly, the quality of the customer’s products increased sharply, even considering the increase in production due to high demand for the billet steel.
Lance Li has been the Business Development Manager, Heavy Industry & Project Business for the past 2 years. He has worked with Moog for 10 years in China and has over 20 years experience in Hydraulic industry. Lance was a University professor before he joined Moog.
K S Shiva Kumar has been the Regional Sales Manager in Hydraulics group for the South & Eastern part of India and SAARC countries for Moog Industrial operations for 8 years. He has more than 14 years experience in hydraulic industry with focus on industrial closed-loop electro hydraulic applications.