Dayton Lamina 9-4040-21 Die Spring 10in Blue Medium-duty

Product Description

The DAYTON LAMINA 9-4040-21 is a medium-duty die spring designed for use in stamping dies, punch presses, and tooling fixtures where consistent, repeatable force is required. Built from chromium-vanadium steel with a D-shaped wire profile, this spring delivers a maximum deflection load of 1,646 pounds at 3.75 inches of maximum deflection. The blue color coding identifies it as a medium-duty spring per industry-standard die spring classification. With a 2.5-inch hole diameter and 1.5-inch rod diameter, it fits standard die sets and is installed and serviced by tool-and-die makers, press maintenance technicians, and machine builders.

This spring is suited for medium-duty press tooling applications in both production and prototype stamping environments. Its 10-inch free length provides substantial stroke capacity, and the 37.5 percent maximum operating deflection rating supports controlled, predictable spring performance across repeated press cycles. It is a direct-fit replacement or upgrade for medium-duty positions in existing die assemblies requiring a 2.5-inch bore and 1.5-inch rod.

Key Features

• Chromium-vanadium steel construction for high fatigue resistance in cyclic press applications
• D-shaped wire profile for improved contact and load distribution within the die set
• Blue color coding indicates medium-duty load class per ISO and JIS die spring standards
• 1,646-pound maximum deflection load at 3.75 inches of travel
• 37.5 percent maximum operating deflection rating supports long service life
• Travel to solid load of 4.48 inches provides a defined safety margin

Compatibility

Designed as an OEM-style replacement or direct-fit die spring for medium-duty stamping die assemblies requiring a 2.5-inch hole diameter and a 1.5-inch rod diameter with a 10-inch free length.

Installation Notes

Die spring replacement and installation should be performed by qualified tool-and-die technicians or press maintenance personnel. Ensure the press or die set is fully de-energized, ram is blocked, and all stored energy is released before servicing. Verify that the rod and bore dimensions match the spring specifications before installation, and never compress the spring beyond its rated maximum deflection to avoid permanent set or fatigue failure.