A mechanical thread rolling machine is a classic piece of equipment that achieves cold thread forming based on the principle of mechanical transmission. It holds an important position in the thread processing field due to its robustness, durability, and intuitive operation. It uses the mechanical extrusion of thread rolling wheels on the workpiece surface to cause the metal material to plastically flow and form threads, eliminating the need for cutting processes, thus saving material and improving thread strength. Structurally, a mechanical thread rolling machine mainly consists of a machine body, transmission system, thread rolling wheel assembly, feed mechanism, and tracking device. The machine body is made of cast iron as a single piece to ensure stability during processing; the transmission system... The core component consists of a main motor connected to a gearbox via a V-belt. After multi-stage gear reduction, it drives two horizontally parallel thread rolling wheel shafts to rotate synchronously. The gear meshing accuracy directly affects the synchronicity of the thread rolling wheels. The thread rolling wheels are fixed to the shafts via key connections, and different types of wheels can be replaced according to the thread specifications. The feed mechanism is mostly manual screw-type, where the operator adjusts the distance between the thread rolling wheels by cranking the screw. Some semi-automatic models are equipped with a central wheel to automate the feed. The positioning device uses V-blocks or chucks to fix the workpiece, ensuring coaxiality during processing. In the workflow, the operator first calculates and adjusts the distance between the thread rolling wheels based on the workpiece diameter and thread parameters. Then, the operator places the workpiece into the positioning device, starts the motor to rotate the thread rolling wheels, and then cranks the feed handle to rotate the thread rolling wheels. The thread rolling wheel slowly approaches the workpiece until the bursting extrusion is completed. Finally, the handle is turned in the opposite direction to retract the thread rolling wheel and remove the finished workpiece. The entire process relies on the rigid extrusion force of mechanical transmission, which is controlled by the operator's feel, making it suitable for experienced workers. Compared with hydraulic thread rolling machines, mechanical thread rolling machines have significant advantages: First, the manufacturing cost is lower, approximately 60%-70% of the cost of hydraulic machines of the same specifications, requiring less initial investment; second, maintenance is simple, as most transmission components are standard parts, and easily replaceable wear parts such as gears and bearings can be easily repaired by ordinary mechanics; third, energy consumption is low, requiring no auxiliary equipment such as hydraulic presses, and the operating power is typically between 1.5-5.5kW. However, it also has limitations, such as the processing accuracy being affected by mechanical limitations, and the thread tolerance generally being within 1... T8-T10 grade milling machines struggle to meet high-precision requirements; the inconvenient adjustment of extrusion pressure, requiring gear replacement or handle force adjustment, makes them unsuitable for processing high-hardness materials (such as tempered steel); low automation necessitates manual loading, unloading, and changeover, significantly impacting production efficiency due to operator skill. Mechanical thread rolling machines have a wide range of applications: in the hardware industry, they process standard parts such as bolts, nuts, and screws; in the construction industry, they process scaffolding accessories and rebar connectors; and in agricultural machinery manufacturing, they produce threads for agricultural machinery drive shafts and connectors. They are particularly suitable for small-batch, multi-variety production scenarios and cost-sensitive small and medium-sized enterprises. With industrial technology advancements, mechanical thread rolling machines are gradually improving. Some models have added PLC control modules for digital feed rate display; high-precision gears and ball screws enhance transmission accuracy; and emergency stop buttons and safety features enhance operational safety. Although they have been replaced by hydraulic and CNC thread rolling machines in high-volume, high-precision processing, mechanical thread rolling machines remain irreplaceable in small-scale production due to their high cost-effectiveness.
