The history and workings of cold heading machines

The history and workings of cold heading machines can be traced back to its earliest inception in Germany. The primary motivation for developing the cold heading machine was to manufacture a large number of bullet casings during World War II.

(1) Under the principle of metal plastic deformation theory, a specific pressure is applied to metal blanks at room temperature, causing them to plastically deform within the die cavity, becoming shaped and sized as desired.

(2) It’s crucial to choose quality “plastic deformation” metal materials, like riveting steel, which have strict standards for their chemical composition and mechanical properties.

(3) Cold-headed bolts and nut forming machinery now come in various models and series. These machines are known for their reliable performance, high efficiency, and stable product quality.

(4) Products being formed require a large forging force, necessitating substantial initial investment in equipment. Hence, production of specifications below M24 is most economical.

(5) The process assures good surface quality and high dimensional accuracy. However, during the forging process, cold work hardening exists, meaning the deformation should not be too large to prevent cracking.

(6) Cold heading technology is suitable for large-scale production and various specifications of products, as this can help lower costs. Modern cold headers have evolved from simple two-station devices to multi-station units. The most recent domestic versions include 6 die, 7 die, 8 die, and other long types of cold heading machines.

Ensuring safety while operating cold heading machines is critical.

1. It is prohibited to operate a cold heading machine wearing gloves.

2. Prior to operation, check whether all fasteners are tightened, protective devices are intact, and continue this practice throughout operation to prevent loosening due to intense vibration, leading to accidents.

3. After adjusting the machine, rotate the flywheel to ensure all parts are functioning correctly. Only after removing the lever used to turn the flywheel should the motor be started.

4. All faults should be accounted for before operation and should run idly for a short period before attempting cold heading.

5. During operation, the operator should stand in a safe location, avoid taking workpieces from mold locations, and inspect products from the bottom instead.

6. When changing products, check and adjust molds and punches carefully.

7. If a fault occurs during production, stop the machine immediately, investigate the cause, and remedy the situation. If the brakes are not functioning, do not operate the machine.

8. Protect insurance boards (insurance rods) from breaking to prevent incidents.

Features

1. The connection between the crankshaft and the body, as well as the striking connecting rod, integrates Swedish imported bearings and high-wear alloy copper tile connections, providing agile operation, strong load-bearing, long service life, and low maintenance cost.

2. The machine body is cast from Alloy-added spheroidal graphite cast iron 500, which has high tensile strength and good wear resistance.

3. The machine is equipped with a brake to reduce the power consumption of the motor.

4. The cutting system uses a guide plate to drive the cutter bar. The back-and-forth motion of the guide plate delivers direct and stable cutting force with good dynamic balance.

5. The forceps system can be rotated 180 degrees or translated, facilitating the arrangement of molding processes.

6. Frequency conversion speed regulation is embedded for speed adjustment within a certain range.

7. A fault detector and protective gear are incorporated. The device automatically stops when there is a malfunction, providing maximum protection for the device and mold.

8. The feed bin is equipped with a push-stop device to enhance feed accuracy.