Metal Pass established its initial business area as a developer of roll pass design program. Metal Pass' roll pass design and roll pass consulting fully utilizes our expertise on rolling process models such as those to predict spread, forward slip, tension correction on the spread and forward slip, and so on. See model list - empirical models. We apply our rolling process models and use our advanced roll pass design programs to analyze and improve your existing roll pass schedules, or to design new schedules for you. We also improve your roll pass design software. We would integrate our accurate rolling process models to your roll pass design software, and add some advanced features such as learning, and the ability to study the existing pass schedules for which the tension correction for the spread, forward slip, etc. is critical. Our excellent training (Ph.D. on this issue), 20 years of related modeling experiences in multiple countries, and the experience of the primary consultant who served as senior roll pass design engineer in a world's top mill engineering company, would guarantee the satisfaction of you.

See our recent paper on roll pass related application: Development of Model-Intensive Web-based Rolling Mill Applications (presented in AISTech 2009).

Quality Discussion

We provide a full range of roll pass consulting, with examples described in the following sections.

The value in a roll pass design program exists primarily in the accuracy of the process models integrated with it. On the sense of modern online software, it is also a great feature to have learning capability. In addition, a roll pass design program with minimal simplifications (e.g. in interstand tension) is also needed. Roll pass software with above-mentioned features should be capable of detecting weaknesses of existing roll pass schedules, and to modify existing pass schedules to create new ones. A poor roll pass design program relies on the designer's knowledge and experience; it only serves as a calculation program to do the things that even the Microsoft Excel can do. In comparison, a high-quality roll pass program hides complicity inside simple user interface and provides rich intelligence and knowledge, so that users without good design experience can still create great roll pass schedules.

From highly technological perspective, a high-quality roll pass schedule is mainly reflected in the accurate prediction of both metal deformation and force/power requirements, among others.

(1) Metal deformation, especially spread and forward slip. This affects overfill and underfill and speed. Overfill causes product shape defects, and underfill lowers down mill productivity and equipment utilization, because more passes may be needed, and grooves and rolls are not fully utilized. The most difficult portion of the exit speed calculation is the forward slip prediction. Accuracy in speed prediction is significant in continuous rolling and is most critical in the high-speed rolling block rolling. If the speed prediction is with too much negative error, then in the region between the current stand and the stand after, the steel would be loose and there is a tendency for metal accumulation. This could cause an accident if too many steel are accumulated. For high-speed mill (e.g. rolling block, or No-Twist Mill NTM) this would be a critical trigger for flutter (mill vibration) and consequent noise. With the trigger for the vibration, many other factors could magnify the scale of the vibration and cause flutter. Flutter may cause the mill hard or impossible to operate. This problem happened in quite a few wire rod mills in USA in the late 90s. During continuous rolling, volume flow per unit time in every stand should be a constant. Therefore, not only the speed, but also the cross-section area has effects on the volume constancy. Prediction error in cross-section area is mainly affected by the calculation error of spread.

(2) Force and power requirements. Positive error in the force prediction leads to either high amount of investment waste or mill utilization waste with positive error, while negative error results in high potential for equipment damage. For a mill supplier, force error would translate into a higher equipment construction cost and sale price. A known mill builder which had about 30% force prediction error sold mills at almost twice as high price as its key competitor. Though it claimed that its mill had higher quality, in fact, most portion of the price difference was considered to be due to its wrong estimate in equipment strength (stand, transmission system and motor, etc.), so it built mill too much stronger than needed!

Roll Pass Schedule Design

We provide a full range of roll pass consulting, with the examples described in the following sections.

Wire rod rolling  (Ask a question)

• We have developed a list of roll pass design programs for wire rod rolling, etc., available either for online use or for purchase as a copy of software.

• We have developed a full range of the rolling process models, which belong to the most accurate and most robust process models for roll pass design in this field.

• The primary consultant, Dr. Benjamin Li, worked as senior roll pass design engineer for a world's top engineering company on wire rod rolling.

• Some of us used to be in the team in a 15-year rolling tests in Germany and a 5-year rolling test in USA and with rich results developed and collected.

• We also have an extensive collection of the publication worldwide in this aspect, especially from Germany, USA, Japan, Canada and China, etc.

• Particular strength and research results exist in the high-speed rolling in the rolling block (No-Twist Mill, or NTM). There are several significant differences between high speed rolling block and regular mill. Firstly, metal deformation pattern, such as spread and forward slip, in such high speed (over 100m/s) is difference, and the rolling block is more sensitive than regular mills to the error of volume constancy because stands cannot absorb the volume difference by adjusting speed, and potential for metal accumulation between stands may lead to flutter (mill vibration) and consequent noise. Also force prediction in such a high strain rate, often over 3000/s, is different from regular mills. Example of the work is the months of measurement in a steel mill, by cutting a hole in each stand of the rolling block (NTM).

• Metal Pass also provides consulting on wire rod and bar mills equipment improvement, and wire rod and bar mills supply, which are tightly related to the roll pass design.

Bar Rolling  (Ask a question)

• Flat bar roll pass: We have a good collection of existing roll pass schedules that are working in US bar mills.

• We also developed related roll pass design algorithms for this type of design, for example, the procedure to predict spread, forward slip, etc.

• Examples of the proposals and development plans for:

  • Technical and Financial Offers - Development of Roll Pass Design Software for Flat Bars

  • Technical and Financial Offers - Development of Roll Pass Design Software for Bars of Triangular and Half Round

Section Rolling  (Ask a question)

• The primary consultant, Dr. Benjamin Li, earned his Ph.D. from Germany on the steel section rolling, especially on section rolling process modeling and roll pass design. Roll pass on angle steel rolling, I-beam rolling and U-section, etc. were intensively studied. Dozens of rolling tests on angle steel hot rolling,  extensive FEM analyses on the angle steel rolling, I-beam rolling, and rolling with hollow section, etc. were carried out.

• Dr. Benjamin Li published his first book (Germany, 1996, in German language) on the process modeling and roll pass design of steel shape rolling, with a deep coverage on the roll pass design for angle steel, I-beam and U-section, etc.

• A list of technical publications were done by Dr. Benjamin Li on the steel shape rolling.

• We have various tools (Finite Element Method, Finite Differential Method, etc.) and technical expertise to determine metal deformation during steel section rolling and to perform steel section rolling roll pass design. We understand how the steel deforms in various type of grooves and in various rolling conditions (steel grade, temperature, rolling speed, etc.).

Pipe/Tube Rolling  (Ask a question)

The primary consultant, Dr. Benjamin Li earned his B.S., M.S. and Ph.D. all on steel rolling and completed a number of projects on the steel pipe/tube rolling. Steel pipe/tube rolling, especially the seamless pipe/tube rolling, is one of the major forms of the steel rolling. Steel pipe/tube rolling covers about one third of the steel rolling contents besides flat rolling and bar/shape rolling. In his B.S. graduation design, Dr. Benjamin Li, under the direction of the then dean Professor Lu, an expert on the steel tube/pipe rolling, completed the roll pass schedule design for the first Chinese tension-reducing piper rolling mill. The pass schedule used the tension to control the pipe wall thickness. Dr. Li also spent three weeks in the pipe rolling mill to test the roll pass schedule. In addition, during the college study and the work as a college teacher on steel rolling, Dr. Li spent about six months in the mills for study and teaching, one third of which was in the steel pipe/tube mills.

Our good understanding on metal deformation in the roll gap and our numerous roll pass projects and developments provide us with ability for the roll pass design for the steel pipe/tube rolling.

We also have analysis tools such as FEM and FDM to determine the metal flow, force and power and temperature during the pipe and tube rolling.

Flat Rolling  (Ask a question)

For those mills without Level 2 system, the rolling draft schedule can be generated in the traditional way just like the roll pass design for the shape rolling (rod, bar, section, etc.). In this case, we can develop roll pass scheduling program in an exact fit to the steel plant, ranging from a simple tool to a large scale Level 2 model. In general we would suggest that the three basic features for the roll pass scheduling program be particularly useful: (1) accurate prediction of roll separating force; (2) basic algorithms for scheduling draft based on the force and finish shape requirements; and (3) basic feature to store the satisfied schedule for future use/reference. Our expertise in both the roll pass design and Level 2 model development will guarantee your satisfaction. You are also guaranteed to save and make large sum of money.

Roll Pass Design Software  (Ask a question)

See recent technical paper: Development of Model-Intensive Web-based Rolling Mill Applications (AISTech 2009).

We can empower your roll pass design program with our expertise on the rolling process modeling and on modern online automation system development.

Our primary focus in this area is to develop customized roll pass software for steel plants, or to customize a third party roll pass software so that it has right fit to a given plant environment. Our understanding of the metal deformation, roll pass design and our full-range of accurate rolling process models enable us to achieve this goal.

The topics for our roll pass software development are discussed in the Mill Software Development and Improvement section.

Improved Design for Wire Rod and Bar Mills

Metal Pass LLC provides consulting services for steel mill vendors to upgrade their mills for higher technical level. Examples of the work areas are to increase rolling speed and to optimize temperature profile throughout the rolling and controlled cooling processes, in addition to the work to improve roll pass schedule and other mill technology level. See Consulting on Improved Design for Wire Rod and Bar Mills.

Improved Design for Wire Rod and Bar Mills

Metal Pass Resources on Roll Pass  (Ask a question)

Examples of Metal Pass resources available for roll pass consulting are as follows:

• Metal Pass Work List - Mill Related Projects
  • Rolling and Roll Pass Development (9 projects)
  • Rolling Process Modeling - Numerical (9 projects)
  • Rolling Process Modeling - Empirical (28 projects)
  • Level 2 Development (17 projects)
• Process models used for the roll pass software development
• Metal Pass roll pass design resources
• Roll pass technical series
• Metal Pass Research Reports
  • Rolling & Roll Pass
  • Modeling
•  A list of available steel mill process models from developed in Metal Pass
• A recent technical paper: Development of Model-Intensive Web-based Rolling Mill Applications (AISTech 2009).

Metal Pass has dozens of research reports and some software applications available at no charge for the Metal Pass Consulting clients (under approval by Dr. Benjamin Li).
 
See the profile for the primary consultant Dr. Benjamin Li. You may also view our company and personnel profiles. Please contact us via email admin@metalpass.com or by phone (001) 503 516 9625 for top quality consulting services.