Screw

Common standards

Grade 12.9 hexagon socket screws are the most commonly used series in high-strength bolt series: Grade 12.9 hexagon socket screws are generally used in situations with high mechanical performance requirements. Places such as injection molding machinery, hydraulic equipment, and mold assembly. The surface hardness of 12.9 grade hexagonal screws after heat treatment can reach 39-44 degrees. The production standards for grade 12.9 hexagon socket screws are based on German standard DIN912, national standard GB/T70.1, American standard, and British standard. The supply range of American grade 12.9 hex socket screws is from # 4-1-1/2, and the supply range of English grade 12.9 hex socket screws is from 1/4-1-1/2 and other common specifications.

The screw specification table includes various parameters, such as head groove, screwdriver tip type, screw head type, appearance surface treatment, and thread specifications. The following is the detailed content:

Head groove and screwdriver tip shape. Common ones include Slotted, Phillips, Phil Slot, Hex Socket, and One Way. one

Screw head type. Common options include Flat, Oval, Round, Pan, Truss, and Hex.

Appearance surface treatment. Common ones include Zinc Plated, Ni Plated, Tin Plated, Zinc Plated/Green Iridite, Radiant Plated, Passive, and Aluminum Finish.

Thread specifications. Common ones include metric screws, American screws, and English screws. An example of a metric screw is an M6 x 8-PPB M6x1 mechanical tooth screw, 8mm long, cross groove, round flat head, black plated. The example of American screws is # 2-56, 0.086-56, which represents the second screw with 56 teeth per inch. An example of an English screw is 1/8 x 0.50- PPB, which represents a 1-inch threaded screw, 0.50 inches long, and PPB represents a round flat head.

In addition, there are special sizes of screws, such as M1.4, M1.7, M1.8, M2.2, M2.8, M3.5, M4.5, M5.5, M7, etc., with diameters of 1.4mm, 1.7mm, 1.8mm, 2.2mm, 2.8mm, 3.5mm, 4.5mm, 5.5mm, and 7mm, respectively