The DURALOCK thread, developed and patented by Roth Hydraulics, has officially received approval for use in ASME piston accumulators. This opens up international markets for the Central Hessian accumulator specialist and once again demonstrates its innovative strength in terms of safety, efficiency, and sustainability. The approval is the result of an intensive technical evaluation by TÜV Hessen and TÜV SÜD. The basis for this was a finite element analysis (FEM) conducted by a qualified engineering firm and subsequently independently verified by TÜV SÜD.

“ASME VIII Division 1 allows for the use of other codes under U-2(g) if a design detail is not addressed there,” explains Lars Dworschak of TÜV Hessen.

“We opted to evaluate local stress according to ASME VIII Division 2, Elastic-Plastic Analysis – Local Strain Limit.”

The results confirmed years of practical experience: The DURALOCK thread offers a safe, robust, and proven solution that has been successfully used by Roth Hydraulics for years in the European PED sector.

“The collaboration with the TÜV experts was characterized by a high degree of professionalism and trust,” Dworschak continues, “which contributed significantly to the safe and efficient transfer of innovative solutions such as the DURALOCK thread into new regulatory areas.”

Greater safety with less material usage

The Roth DURALOCK thread is the result of years of development work and represents a new generation of technical connection systems. Thanks to an optimized thread geometry with a reduced flank angle and increased thread base radius, radial forces are reduced and stresses in the pipe are significantly lowered. The result: a lower risk of bending, higher fatigue strength, and material savings of up to 25 percent—while simultaneously increasing safety.

These improvements have been verified through extensive burst and cyclic loading tests and were monitored and validated by TÜV Hessen.

“The Roth DURALOCK thread brings an additional boost in robustness, safety, and efficiency to our storage systems,” emphasizes Harald Velte, Head of Development & Design at Roth Hydraulics.

“This enables us to meet the demanding requirements of our customers worldwide even better.”

Hydraulic Accumulator Solutions with a System

Roth Hydraulics develops energy-efficient hydraulic accumulator solutions for applications where hydraulic energy needs to be stored or converted: from piston, bladder, and diaphragm accumulators to complete accumulator systems. The modular system enables customized, economically attractive, and technically precise solutions.

With ASME certification of the DURALOCK thread, Roth Hydraulics strengthens its position as a technology leader in the international market for hydraulic energy accumulator systems while setting new standards in terms of safety, efficiency, and durability.