(1)By size (referring to the size of the square head): 1/4″, 3/8″, 1/2″ three specifications
(2)According to length: long socket, short socket, E-shaped socket
(3)By side: 6 corners, 12 corners, 4 corners
(4)By appearance: single groove, double groove, knurled, straight, nickel-plated and chrome-plated, etc.
(5)By usage: there are manual socket wrench and pneumatic socket wrench (black, chrome molybdenum steel)
(6)According to different screws: outer hexagonal socket, outer torx socket; inner hexagonal socket, inner 12pt socket, E-type socket, square socket etc.
(1) Bright chrome: like a mirror, very bright
(2) Chromous: no gloss
(3) Electrophoresis: black with brightness. Under an external DC power supply, the charged particles move toward the cathode or anode in a dispersed medium to promote the separation of substances;
(4) Phosphating: black, but dull. The socket is immersed in the phosphating solution, and a layer of water-insoluble crystalline phosphorus is deposited on the surface, which is the conversion process of phosphate
Blank (various specifications)--grinding (removing burrs, etc.)--turning (mainly forming)--grinding surface--engraving (such as knurling, printing LOGO, etc.)--heat treatment (in order to increase its hardness )--electroplating (nickel or chromium, etc.)--grabbing black, etc.
(1) Look at the surface: whether there are burrs, whether the specifications meet the size standards, whether there are scratches, etc.
(2) Material property: use special tools to measure torque and hardness; measure size; salt spray test, etc.(When the size of a hexagonal or twelve-cornered socket is less than or equal to 32MM, its hardness value is not lower than HRC39, and when it is greater than 32MM, the hardness is not lower than HRC35)