1. Countersunk hole: sink the head of the fastener completely into the stepped hole of the part.
2. Through hole: refers to the hole that can pass through.
3. Blind hole: refers to a hole that is blocked, that is, a hole that is blocked at one end.
1.The role of countersunk holes: used to install bolts or other connecting parts.
2. The role of through holes:
(1) It is used to transport liquid, gas, dust loaded objects, etc. under the configuration of the pump.
(2) In integrated circuit design, it is a small opening in the insulating oxide layer that allows conductive connections between different layers, and the pack and unpack (PAU) process is used to build the through hole array.
3. The role of blind holes:
(1) It is used for the connection of two or more parts in machining. To do this, tapping is required in blind holes, and through holes, bolts, etc. are required.
(2) In the printed circuit, the blind hole is located on the top and bottom surfaces of the printed circuit board, with a certain depth, which is used for the connection between the surface circuit and the inner circuit below, and the depth of the hole usually does not exceed a certain ratio (diameter).