The main categories include ordinary screws, machine screws, self-tapping screws, and expansion screws.
Screws:
Cap screws have been limited to full-tooth fasteners.
Hex cap screw Hex cap screw and Hex bolt Hex bolt As the name suggests, the head is a hexagonal male thread fastener designed to use a wrench to turn. According to ASME B18.2.1, Hex cap screws have smaller head height and rod length tolerance than Hex bolts, so ASME B18.2.1 hexagon screws are suitable for all hexagon bolts. Places also contain large hexagon bolts that are too large to use.
Socket cap screw (also known as socket screw or) is a screw with a hexagonal head in the head, which can be tightened or loosened by inserting a hex key (Allen wrench or Allen key) into the inner hole. The most commonly used socket head cap screws are cap screws with a head diameter of about 1.5 times the major diameter of the thread (1960 series). Other head types include a Bottom head cap screw and a tapered screw hole. Countersunk head cap screw. The counterbore design allows the screw head to be able to rotate without being exposed on the surface of the object to be fixed. Therefore, it is often used where the surface is small and the conventional wrench is inconvenient to use.
Machine screws Machine screws are generally less than 1⁄4 inch in diameter (4# to 12#), usually full teeth and turned by a screwdriver, such as slotted, cross or hexagonal.
Wood screws, machine screws; but according to different uses can also be divided into many categories; machine screws, can be divided into longitudinal fastening screws and horizontal expansion screws; according to the thread can also be divided into:
A: triangular thread (60 degrees): combination / locking / expansion
B: triangular thread for pipe (55 degrees): combination/locking 3)
C: trapezoidal thread (30 or 29 degrees): power transmission
D: square thread ( 90 degrees) : power transmission
stainless steel screw:
Machine (Tread) Vehicle Screws, Axis Screws And Shafts For Motorcycle Or Bicycle
Sewing Screws, Shafts, Screws And Shafts For Sewing Maching
Stop Screws Socket Set Screws
Stainless Steel Wide Screw Stainless Steel Coarse Thread Screws
Stainless Steel Screws Stainless Steel High-Low Thread Screws
Stainless Steel Machine Screws Stainless Steel Machine Screws
Stainless Steel Self Drilling Screws
Stainless Steel Self Tapping Screws Stainless Steel Self Tapping Screws
Stainless Steel Self-Cracking Screws Stainless Steel Thread Cutting Screws
Stainless Steel Triangular Screw Stainless Steel Tri-Lobular Thread Screws