Bolts are mainly used in the following aspects: fixed anchor bolts, also known as short anchor bolts, are used to fix equipment without strong vibration and impact together with root irrigation. The movable anchor bolt, also known as the long anchor bolt, is a detachable anchor bolt used to fix heavy mechanical equipment with strong vibration and impact. The expansion anchor anchor anchor bolt is often used to fix the simple equipment or auxiliary equipment. The expansion anchor anchor bolt device shall meet the following requirements: the distance from the bolt center to the bottom edge shall not be less than 7 times the diameter of the expansion anchor anchor bolt; The root strength of the expansion anchor anchor anchor bolt of the device shall not be less than 10MPa; There shall be no crack at the drill hole, and attention shall be paid to prevent the drill bit from colliding with the reinforcement and buried pipe in the root; The diameter and depth of the drilling hole shall match with the expansion anchor anchor bolt. Bonding anchor bolt is a commonly used anchor bolt in recent years. Its method and requirements are the same as those of expansion anchor anchor bolt. However, when bonding, pay attention to blow out the sundries in the hole, and do not get damp.

1. The main body is a large equipment, which requires device accessories, such as a mirror, mechanical seal seat, reducer frame, etc. This is the stud used. One end is screwed into the main body, and the other end is equipped with nuts after the accessories are installed. Since the accessories are often removed, the threads will be worn or damaged, so it is very convenient to replace them with stud bolts.

2. When the connecting body is thick and the bolt length is very long, the stud bolt will be used.

What are the common screw specifications and models? Let's talk about it in detail today.

1. Inch thread → common specification is 2 #; 4#; 6#; 8#; 10#; 12#; 1/4; 7/32; 5/16; 3/8; 1/2; 9/16; 3/4。 Unit in inches.

2. Tooth number/tooth pitch: the definition of tooth number → the number of tooth lines contained in an inch (25.4mm) of length. Pitch definition → distance value between two adjacent threads. Tooth number and tooth pitch conversion → tooth pitch=1 inch/tooth number

3. Nominal length: metric and imperial. Metric nominal length → common values are 5, 6, 6.5, 7, 8, 9, 9.5, 10, 11, 12, 13, 14, 15, 16, 18, 19, 20, 21, 25, 28, 30, 31, 32, 35, 40, 42, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120. Unit: mm. English nominal length → common values are 1/4, 5/16, 3/8, 7/16, 1/2, 5/8, 3/4, 1, 2, 3. Unit: inches.

4. Head type: use letters to indicate the type of head type. Please refer to the classification of common screw head types in the previous text

5. Tooth shape/tail shape: use letters to indicate the variety of tooth shape/tail shape. Please refer to the previous text "Classification of common screw tooth shape/tail shape".

6. Groove type: refer to the previous text "Classification of our common screw groove types". There is no need to mark the cross groove or slotless (such as punching hexagon head screw) here, and other groove types need to be explained in words.

7. Special marks: general conditions do not need to be marked, and their characteristics are described in words at this position.

For example, the screw specification name is described as "4-0.7x70PM ± tooth length 35", which means "4" is the nominal diameter of the screw thread, "0.7" is the pitch, 70 "is the nominal length of the screw," P "indicates that its head type is pan head," M "indicates that its tooth type/tail type is machine thread type, and" ± "indicates that its groove type is" ± groove ", which can also be indicated by" plus or minus groove ". "Tooth length 35" is a special mark, specifically indicating the thread length value of this screw.