Gardner Spring MB1250-040 Belleville Disc Spring

Product Description

The GARDNER SPRING MB1250-040 is a Belleville disc spring - also known as a conical washer spring - designed to deliver high load capacity in a compact axial envelope. With an outer diameter of 1.25 inches, an inner diameter of 0.63 inches, and an overall height of 0.082 inches, this spring generates 47 pounds of load at its rated deflection of 0.006 inches. Constructed from steel, the MB1250-040 suits applications where precise, consistent spring force must be maintained in tight spaces. It is installed by mechanical contractors, millwrights, and precision assembly technicians across industrial and trade equipment.

This Belleville disc spring is used wherever a high spring rate is needed in a minimal stack height - common in bolted flange assemblies, valve bodies, pressure fittings, and rotating equipment. The 5/8-inch bolt size compatibility makes it a practical fit for standard fastener hardware found in HVAC, plumbing, and industrial piping assemblies. It can be stacked in series to increase deflection or in parallel to increase load, depending on the design requirement.

Key Features

• 1.25-inch outer diameter with 0.63-inch inner diameter for use with 5/8-inch bolt hardware
• 47-pound rated load at 0.006-inch deflection provides high force in a compact profile
• Overall height of 0.082 inches allows low-profile stacking configurations
• Steel construction for durability in mechanical load-bearing applications
• Sold in packages of 12, with no minimum order beyond a single package

Compatibility

Sized for use with 5/8-inch bolt assemblies. Designed as a standard Belleville disc spring for use in bolted flange connections, valve assemblies, and mechanical equipment requiring controlled axial load.

Installation Notes

Installation is performed by licensed mechanical or industrial technicians. Before servicing any assembly containing disc springs, relieve all system pressure and de-energize related equipment per applicable codes. When stacking multiple disc springs, verify orientation - series versus parallel - against the load-deflection requirement before torquing fasteners. Do not exceed the rated deflection, as flattening the spring beyond design limits will cause permanent set and loss of spring function.