Fenn Model 101 10.5" x 12" 2-High / 4-High Combination Hot Rolling Mill

Description

Fenn Model 101 Combination 2-High / 4-High Hot Rolling Mill — IRM Factory Refurbished

The Fenn Model 101 is a heavy-duty combination hot rolling mill that carries out both breakdown and precision finishing in a single stand. Configured for the hot rolling of specialty magnesium and other temperature-sensitive alloys from heavy incoming plank down to thin finished sheet, the machine will be factory refurbished and re-engineered by International Rolling Mills (IRM). It combines the roll-bite capacity needed for heavy early reductions with the fine-gauge and surface control required at final thickness, allowing the rolling schedule to progress from incoming plank through breakdown and finishing operations on a single mill stand, subject to the required reheating, intermediate cutting, and customer-provided material-handling steps.

In the 2-High arrangement, the mill uses nominal 10.500" diameter rolls for high-reduction breakdown passes where the stock is thick and drafts are large. Converting to the 4-High arrangement provides nominal 3.250" diameter work rolls with the same 12.000" roll face for the light, closely controlled finishing passes where final thickness and surface finish are established. The 12.000" roll face supports both straight- and cross-rolled orientations, accommodating a range of finished widths with suitable edge margin.

A rigid four-column housing with a total column cross-sectional area of approximately 318 in² provides an available separating-force capacity of approximately 550,000 lbf and the frame stiffness needed to support consistent gauge control across the roll face.

The mill is powered by a new 150 HP inverter-duty AC motor driven by a new 150 HP variable frequency drive with closed-loop vector control, providing smooth, high-torque operation and stable low-speed rolling across the anticipated pass schedule. All electrical controls are new. The PLC and control components are housed in a NEMA 12 enclosure, and the main swing-arm operating station includes a touchscreen HMI and full operator controls.

Approximately 2-meter manual roller tables are installed at the mill entry and exit for handling the incoming plank and intermediate workpieces. Identified mill nip points are mechanically guarded.

The mill is supplied with new H13 hot-work tool-steel rolls. H13 is selected for its thermal stability and resistance to thermal fatigue (firecracking) at elevated temperature rather than principally for hardness, because magnesium exhibits relatively low flow stress within its hot-working range. Final roll surface finish and treatment will be selected after review of the customer’s complete magnesium-alloy composition, including its lead content, with the objective of minimizing material pickup, galling, surface contamination, and marking during hot rolling.

Roll gap is set by an electro-mechanical screwdown assembly driven by two new 2 HP inverter-duty motors with encoders and closed-loop vector control. Both screw positions adjust simultaneously or independently, providing fast centerline changes, fine parallelism control, and precise, repeatable gap positioning. A digital screw-position reading for each side is displayed on the HMI, giving the operator a repeatable setup aid and an indication of screw position at both ends of the roll.

When used with the optional thickness measurement gauge system, the operator can make controlled screwdown corrections between passes based on measured material thickness. Because the process involves discrete-piece rolling with adjustments made between passes, it is better suited to operator-directed correction based on measured thickness than to conventional continuous-strip closed-loop automatic gauge control.

KEY FEATURES
* Combination 2-High / 4-High configuration in a single stand for breakdown through finish rolling
* Nominal 10.500" diameter 2-High rolls and 3.250" diameter 4-High work rolls with a 12.000" roll face
* Approximately 550,000 lbf separating-force capacity
* Approximately 318 in² of total column cross-sectional area
* New H13 hot-work tool-steel rolls, with final surface condition selected for the customer’s alloy and rolling process
* New 150 HP inverter-duty AC main-drive motor
* New 150 HP variable frequency drive
* 480V, three-phase electrical configuration
* Closed-loop vector main-drive control
* Electro-mechanical screwdown system
* Two new 2 HP inverter-duty screwdown motors
* Two new 2 HP variable frequency drives for the screwdown system
* Encoder feedback and closed-loop vector control for the screwdown motors
* Simultaneous or independent screw adjustment
* Reference digital screw-position readout for each side displayed on the HMI
* All-new electrical controls, including the PLC, housed in a NEMA 12 enclosure
* Touchscreen HMI and operator controls in the main swing-arm operating station
* Approximately 2-meter manual roller tables at the mill entry and exit
* Mechanically guarded mill nip points
* Approximate dimensions: 154" L × 78" W × 112" H
* Approximate weight: 30,000 lb

AVAILABLE OPTIONAL FEATURES AND UPGRADES:

HEATED-ROLL PACKAGE:
The nominal 10.500" diameter rolls are bored to accept electric cartridge heaters capable of producing a maximum roll temperature of approximately 232°C. These rolls contact the material directly when the mill operates in the 2-High configuration. When the mill is converted to the 4-High configuration, they function as backup rolls and transfer heat conductively to the nominal 3.250" diameter work rolls through the roll-to-roll contact interface.

Temperature is controlled through Watlow digital temperature controllers and Watlow DIN-A-MITE power controllers located in the central operating station. K-type thermocouples provide real-time temperature measurement and closed-loop feedback to the control system.

The heated-roll system minimizes thermal shock as heated stock enters the roll bite and helps maintain a more consistent roll temperature during hot rolling operations, supporting improved material flow, more uniform reductions, and stable process performance. In the 4-High configuration, actual work-roll temperature will depend on conductive heat transfer from the heated backup rolls, rolling conditions, operating time, and heat loss during production.

The 232°C maximum temperature of the heated rolls is established to protect the precision needle-bearing components from thermal softening and reduced service life. If a higher heated-roll temperature is required, IRM can evaluate conversion to bronze bearings, which tolerate higher roll-neck temperatures, subject to review of load capacity, bearing design, wear, cooling, and maintenance requirements.

The required roll temperature, heated-roll configuration, and bearing arrangement will be confirmed against the customer’s alloy, rolling schedule, and finishing requirements. Required controls, electrical components, guarding, and safety features associated with the heated-roll package are included for operation at the specified temperature.

THICKNESS MEASUREMENT GAUGE SYSTEM:
A thickness measurement gauge system can be supplied as a separately priced option to provide repeatable thickness feedback during piece rolling. The final gauge technology, measurement range, and mounting arrangement will be selected after confirming the rolling sequence, material temperature and surface condition at the measurement point, thickness range, width variation, and pass direction.

The selected system will provide measurement feedback for operator-directed screwdown corrections between passes. Final gauge configuration and integration will be determined as the process and operating requirements are developed.

SCOPE OF SUPPLY, EXCLUSIONS, AND PROCESS RESPONSIBILITY:

APPLICATION BASIS AND PROCESS RESPONSIBILITY:
The proposed mill configuration is based on the customer’s stated requirement to process preheated, extruded magnesium plank approximately 178 mm wide × 6.35 mm thick into finished sheet approximately 255 mm wide × 0.25–0.33 mm thick.

The mill will be configured with the mechanical, electrical, and control capabilities described in this proposal to support the intended application. However, actual processing results are dependent on the characteristics of the customer’s alloy and the process developed by the customer, including material preparation, rolling temperature, temperature uniformity, reduction per pass, pass sequence, reheating frequency, straight or cross rolling, width development, material flatness, roll condition, measurement method, and operator practices.

Development and validation of the rolling process, pass schedule, material-handling procedures, and finished-product requirements remain the customer’s responsibility. IRM does not guarantee that a particular finished thickness, width, tolerance, surface condition, flatness, throughput, or material property will be achieved unless expressly stated in a separate written performance guarantee.

All process recommendations and technical estimates provided by IRM are offered for evaluation purposes and are subject to the Process Responsibility and Performance Disclaimer set forth in Section 12 of IRM’s Standard Terms and Conditions.

MATERIAL PREHEATING AND REHEATING:
Material preheating and reheating will be performed in separate customer-supplied furnaces. Based on the total reduction, multiple reheating cycles should be anticipated throughout the pass schedule.

The controlled-atmosphere argon furnaces, inert-gas supply and purge system, furnace controls, and associated furnace material-handling equipment are outside IRM’s scope of supply.

MATERIAL HANDLING:
The mill is supplied with approximately 2-meter manual roller tables at the entry and exit for handling the incoming plank and intermediate workpieces. As the material is reduced in thickness, its length will increase substantially. Depending on the incoming plank length and selected rolling sequence, the customer may need to cut the material between stages or make other provisions for handling and supporting the material throughout its process. Any equipment or procedures required beyond the supplied entry and exit tables are the customer’s responsibility.

Images shown are representative of the machine. The actual mill may differ in appearance based on configuration, optional equipment, guarding, controls, and final build.