Round Head Torx screws ® Socket Screws)
1. Head design: Integrated round head and plum blossom groove
Round Head:
• Hemispherical top: The diameter is usually 1.5-2 times the diameter of the screw (such as a round head diameter of about 6-8mm for a 4mm diameter screw), which disperses stress and avoids scratching the surface with sharp corners;
Embedded design: The transition radius between the head and the rod is ≥ 0.5mm, reducing stress concentration and suitable for vibration environments (such as mechanical equipment and sports equipment).
• Plum blossom trough (Torx) ®/ Star shaped slot):
Hexagonal star shaped groove: High torque transmission is achieved through a dedicated batch head (such as T10-T25 specification), and the anti slip ability is increased by more than 60% compared to the cross groove. It is suitable for high-speed installation of electric tools (recommended speed ≤ 2800RPM);
Anti overload design: The groove contains positioning ribs. When the torque exceeds the design value, the ribs and the batch head undergo elastic deformation to avoid head breakage.
2. Thread and stem characteristics
• Thread type:
Self tapping thread (ST series): The tip contains 3-4 cutting edges, which can directly penetrate thin metal plates (thickness ≤ 2mm) or plastics without pre drilling holes;
Machine thread (M series): It needs to be used with nuts or internal threaded holes and is suitable for high load scenarios (such as steel structures and automotive parts).
• Material and coating:
Carbon steel (10B21/45 # steel): After heat treatment, the hardness reaches HRC35-40, suitable for indoor conventional loads;
Stainless steel (304/316): excellent corrosion resistance, suitable for outdoor or high humidity environments (such as food machinery, medical equipment);
• Surface coating:
Galvanized (blue white/color zinc): Salt spray test ≥ 48 hours, meeting general industrial rust prevention requirements;
Nickel based alloy coating: salt spray ≥ 1000 hours, suitable for marine or chemical corrosion areas.
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