Trapezoidal Threaded Rods DIN 103

DIN 103 trapezoidal threaded rods are externally threaded drive components with a metric trapezoidal thread profile. The DIN 103 series defines the ISO metric trapezoidal thread system, including thread profiles, dimensions, and tolerances across its individual parts. The thread has a 30° included flank angle and is designated by Tr, nominal diameter, and pitch, such as Tr 30 × 6.

Unlike ordinary metric fastening threads, trapezoidal threads are primarily intended for transmitting motion and axial force rather than making permanent bolted joints. Their broad flanks and relatively large thread depth make them common on lead screws, feed screws, adjustment mechanisms, lifting devices, machine tools, and mechanical actuators. They are often also called trapezoidal threaded spindles, trapezoidal lead screws, or trapezium threaded rods, depending on the industry and market.

DIN 103 specifies the thread system rather than a particular rod-end configuration. Commercial trapezoidal threaded rods may have plain cut ends, chamfered ends, or specially machined journals depending on how the spindle will be installed. The thread itself may also be produced by rolling or cutting, depending on the required diameter, length, material, and application.

Right-hand thread is the normal configuration, while left-hand versions are available for applications requiring reverse movement or paired screw mechanisms. When selecting a DIN 103 trapezoidal threaded rod, the key parameters are nominal diameter, pitch, thread direction, thread tolerance, length, and compatibility with the mating trapezoidal nut.