MULPIC® Plate Mill Cooling Technology for Profit Maximization

MULPIC® is an advanced Online Accelerated Cooling (ACC) and Direct Quench (DQ) system specifically designed to address the challenges of online cooling. Its fundamental strength lies in its uniform and powerful cooling capabilities, with precise flow control across a wide range of products. With nearly 30 reference projects, MULPIC® is the market-leading plate cooling technology.

The Core Design Principles of MULPIC®

Continually enhanced to align with technological advances, providing a proven solution for

• Temperature accuracy and uniformity
• Alloy and operational cost savings through digitalization and precise cooling
• Intermediate/transfer bar cooling
• Coil production on plate steckel mills in addition to discrete plates
• Low CAPEX hybrid machines that integrate with existing laminar cooling sections
• Low maintenance requirements
• Large flow control range within a single header design

Compared to Other Cooling Technologies that Use Separate Designs for Direct Quenching (DQ), MULPIC® Offers Several Advantages

• Uniform heat transfer mechanism
• Consistent application of water crown and edge masking
• Shorter machine length
• Easier maintenance
• Reduced spare parts requirement

These factors contribute to improved product quality through uniform cooling, an expanded range of products that can be produced inline, and reduced operating costs.

Advanced flow control valves from Primetals Technologies are assembled and tested in-house, providing position accuracy and responsiveness not available from standard valve assemblies. The design has been optimized to simplify maintenance, featuring one-click calibration via the human-machine interface (HMI).

High Nozzle Density & Dynamic Water Crown Control

With over 200 nozzles per meter width of header and achieving the highest heat transfer in the impingement zone around each cooling jet, the high nozzle density and flow control combine to deliver a wide range of cooling rates. The header design is consistent throughout the entire length of the machine, allowing any header to handle the full range of cooling requirements. This provides the opportunity to maximize alloy cost savings by targeting appropriate structure-property relationships.

Water distribution across the width is dynamically controlled using water crown control valves rather than by the physical distribution of nozzles. This enables the production of products of any dimension with excellent temperature and flatness uniformity, even when maximum cooling rates are utilized during direct quenching (DQ). This expands the product range and reduces downgrades and costly reworking of material. For example, abrasion-resistant plates with a hardness of up to 500 Brinell are now produced online, eliminating the additional energy and handling costs associated with processing in a separate heat treatment line. Cooling water is maintained within the machine and, when necessary, separated into cooling zones using variable-pressure Zone Separation Sprays (ZSS). This is a cost-effective and low-maintenance solution.

The Zone Separation Sprays (ZSS) eliminate the need for damming or pinch rolls in direct quenching sections:

• Reducing maintenance requirements
• Eliminating the risk of plate marking
• Improving uniform cooling along the plate length, as no threading sequence is needed
• Inbuilt Quality Features

Each MULPIC® Plate mill cooling machine is designed and constructed with quality at the forefront to ensure longevity and availability.

Key Quality Features Include

• Extensive use of stainless steel for the headers and machine pipework
• Self-cleaning filtration localized to the machine, with last chance filters on the machine and nozzles designed to avoid blockages
• Automated header cooling system for protection
• Top header in-situ maintenance enabled by the ability to raise the top header
• Flexible Revamps and Upgrades: Low-Cost Solutions to fit any mill line
• The modular, flexible design of the MULPIC® can be tailored to suit the demands and budgets of different users

Flexible Revamp Solutions

Revamp projects require an innovative and adaptable approach to overcome existing physical or process constraints. The length of a MULPIC® machine can be customized to fit into existing mill lines, depending on the available space and the target product mix. The Return on Investment (ROI) can be less than one year, even considering the total project costs. The modular design of the MULPIC® system ensures ease of future expansions by simply adding modules.

Hybrid Cooling Solution

MULPIC® technology can replace part of an existing cooling machine, creating a hybrid solution. Newly installed MULPIC® banks can be used in conjunction with the existing cooling equipment, all controlled by a single new automation system. The benefits of a MULPIC® installation are realized with low investment costs.

Upgrade of an Existing MULPIC®

MULPIC® is continuously developing in line with advances in technology. Upgrade packages are available for existing MULPIC® installations, including:

• Flow control valve upgrade
• Level 1 and Level 2 automation upgrades, including digital twins
• Condition monitoring system
• Digitalization package

Digitalization: Reducing Costs, Improving Quality and Operational Efficiency of MULPIC

The MULPIC digital twin is an offline software package that utilizes models or real process data as inputs to perform complex simulations and analyses, predicting how the actual cooling process will perform. It provides a complete description of the cooling technology, including efficiency curves and performance limits. The primary purpose is to mirror the online core cooling models while running in a standalone environment.

Another key aim is to predict the mechanical property performance of the final product—the digital twin model's microstructure evolution during cooling to predict final structure-property relationships. Yield strength, tensile strength, elongation, and hardness are currently included. Current functionality includes detailed post-processing analysis, facilitating process optimization, and maximizing alloy cost savings while also speeding up and lowering the cost of product development.

Information regarding scale and surface quality is available from the scanning pyrometers located on the entry and exit sides of the MULPIC®. Quality issues are highlighted early in the process, reducing downgrades and increasing profitability.

The web-based reporting tool for MULPIC provides detailed insights into the performance of cooled products, including final temperature, cooling rate accuracy, and statistical process control. By highlighting potential quality issues through variances in process parameters, the system enables early detection of problems, reducing downgrades and enhancing profitability.

The condition monitoring system records and analyzes key process parameters and cooling performance over time. It provides timely alerts when maintenance is required for specific parts of the equipment, helping to avoid unnecessary and unplanned machine downtime. This approach reduces maintenance costs and improves equipment availability, ensuring efficient and reliable operations.

Water Treatment Technology for Plate Mills

For consistent and reliable plate mill cooling, Primetals Technologies can design and supply the water treatment plant as an integrated supply solution. This system is typically dedicated to MULPIC® and is considered one of the most cost-effective solutions in terms of operating costs, reliability, and assured water quality.

Key Features of the Water Treatment Plant Design Include

• Closed water system to minimize makeup water consumption and deliver a sustainable solution. An optional wastewater recovery system is available; however, it is typically more cost-effective as part of the overall plant system due to the relatively low amount of wastewater generated by MULPIC.
• Filtration system designed by Primetals Technologies to control suspended particles in terms of concentration and size
• Direct pumped option, a solution usually favorable for modernizations
• Water supply via an overhead tank, a solution typically favorable for new plate mills
• Energy conservation through the use of variable speed drives enabled by either fluid couplings or variable frequency drives
• Additive dosing systems specifically designed for local water conditions to promote equipment reliability and longevity
• Integrated control system with condition monitoring for the complete solution