what is hex bolt？

What is hex bolt？

Hexagon bolts, hex head bolts (partial threads) - Class C and hex head bolts (full thread) - Class C. Also known as hex head bolts (rough), hex head bolts, black iron screws.

According to the  way of connection, there are common and reamed holes. The bolts for  reaming holes should be matched with the size of the holes. When used by  lateral forces, the head shape has a hexagonal head, and the round head ,  square head, countersunk head, etc. The general countersunk head is  used in places where the surface is smooth and not protruding after the  connection is required, because the countersunk head can be screwed into  the part. The round head can also be screwed into the part. The  tightening force of the square head can be Larger, but larger in size. Hex heads are the most commonly used.
In  addition, in order to meet the needs of locking after installation,  there are holes in the head and holes in the rods, which can not loosen  the bolt when it is vibrated.

The  size specified by the manufacturer for a bolt indicates the diameter,  pitch, shank length, grade, head and thread length of the bolt. Bolt sizes can be calculated in millimeters or inches, but the specified inches in bolt measurements are multinational. This  means that a 1⁄2 inch x 12 x 4 inch 2 hex bolt head 1 inch thread  should be required. The lower bridge screw manufacturer tells you that 6  steps allow you to accurately measure the bolt size.
 

How to measure hex bolt 

step 1:
  The diameter of the handle is measured. The handle is part of the bolt of the system. Use a caliper to get a precise diameter of the measuring rod. In the above example 1/2 inch is the diameter of the shank.

Step 2:
  Determine the pitch along the axis through the calculation thread. By measuring an inch of the axis and calculating how many threads (rise and depth are one thread) inches. If there are 12 threads per inch, read 12.

Step 3:
  Measuring the length of the rod. The length of the handle is from the satisfaction to the other end. Such as: 4 inches.

Step 4:
   Determine the level of the bolt. Grades are used to describe the type of metal or material used to produce the bolt. The level of the bolt can indicate the head of the mark. It means that soft steel is used to make the bolts.

Step 5:
  Look at the head of the bolt. The shape of the head shows what type of bolts. If it is flat, square. Hex head bolt head has six sides. Carriage bolt head and dome.

Step 6:
  Measure the length of the line. This is the number of axes, actually the threads. The length of the line is 1 inch.