top of page

Precision Ring Forming with Grotnes Forging Expanders

Grotnes’ forging expanders are part of a premier line of automated equipment crafted for precision ring shaping, advancing metal forming capabilities for industrial manufacturers.

Why Sizing Matters

Forged rings begin their manufacturing process on a ring rolling mill. Despite the precision of ring rolling, sizing — adjusting the ring to its final dimensions — remains a sometimes overlooked yet crucial step. Sizing not only ensures the exact dimensions but also enhances the part’s roundness and can significantly reduce or even eliminate the need for finish machining, cutting both material waste and production time.

Grotnes’ forging expanders play a vital role here. They can precisely adjust cylindrical parts, improving their microstructure and material properties. Seamless rings start as cylindrical preforms, which are then pierced and shaped on a ring roller. Post-rolling, they may undergo heat treatment and machining to create components for various applications, from wind turbines to aerospace engines.

The final sizing step is crucial, especially after heat treatment, to correct any distortions and stabilize the part’s structure. With the appropriate tooling, machining allowances are minimized, and both inner and outer diameters achieve high precision. Plus, with stacked tooling options, a single machine can size a wide range of diameters, enhancing the efficiency of the ring production process.

How Grotnes Forging Expanders Work

When forming rings with Grotnes’ forging expander, the machine operator, equipped with the necessary tooling, sets up the machine for automatic operation and decides if gauging will be included in the process. The part is then placed onto the machine using lifting equipment, where it rests on a rotating support. The operator initiates the automated sequence by pressing the start button, prompting the machine to expand the part to the desired diameter and shape using segmented dies.

After the machine completes the cycle and stops in a closed position, the part is automatically rotated if required, and the process repeats until completion. Once finished, the operator removes the part.

The machines Human-Machine Interface (HMI) allows for comprehensive control and oversight of the operation. Operators can input parameters, access up to 50 preset recipes and monitor the machine’s status through various indicators and functions, such as current and target diameters, starting diameter and a die constant for accurate readouts. Additional features include a gauging mode for measuring the ring’s diameter, manual mode for operation and password protection for securing sensitive data and operations.

Capable to Meet Your Operational Demands

Our forging expanders, with their precision engineering, are revolutionizing the process of ring forming. The 24-HE-600-12 model, a 600-ton hydraulic expander, is adept at sizing aerospace rings up to 1200 mm in diameter, featuring water-cooled jaws for swift cooling post-expansion.

For larger rings, the 44-HE-2400-12 and 48-HE-3300-12, both 2,400- and 3,300-ton expanders respectively, can handle up to 7200 mm diameters, catering to power generation, aerospace and construction industries. They boast indexing rollers for ring rotation and tool-change efficiency. With some models are more common than others, there is no set tonnage for available expanders, and machines can be customized to meet customer specifications. Also, Grotnes offers both “Push” and “Pull” type expanders to allow for a wide range of diameters and part heights. In the face of surging demand for large-diameter seamless rings, our expanders aid manufacturers in enhancing quality while cutting costs and delivery times. These expanders are pivotal in sizing rings for applications like wind turbines, offshore structures and automotive components. The aerospace sector, in particular, relies on Grotnes for precision calibration of rings used in jet engines crafted from exotic alloys.

The benefits are clear: reduced machining allowances due to the expanders’ precision, resulting in near-perfect circularity with tight tolerances. The precision also alleviates internal stresses, leading to fewer defects and more stable product for subsequent processes. Ultimately, this translates to significant cost savings in both material and machining time.

How Grotnes Can Help

Sometimes, selecting the right machinery for your manufacturing operation can be complex. Grotnes staff are at the ready to help guide you through the selection process, ensuring you invest in equipment that meets your production needs.

By understanding your distinct operation requirements, our experienced professionals can help match you with a forging expander that optimizes your production line, enhances your product quality and delivers on the promise of performance and reliability that Grotnes’ reputation is built upon.

Contact our team today for to begin the consultation process or learn more about our solutions!

55 views0 comments


bottom of page