一，Seamless steel pipe drilling method
1. Use a special punch to drill the inner diameter of the steel pipe to the required specifications. Before drilling, you should check whether the pipeline has cracks, folds, severe corrosion and other defects. If there are any defects above, it must be cleared before drilling.
2. On the punching machine, select the corresponding drill bit according to the required steel pipes (usually a diamond stone bead electric drill with a diameter of 32mm or 40mm), then adjust the appropriate speed and feed, and then start drilling.
3. When the wall thickness of the steel pipe is less than 4mm, a small diameter diamond -type electric drill can be used; if the wall thickness is greater than 4mm, the large diameter diamond -type electric drill (such as φ50) should be used.
4. During the drilling process, pay attention to the bottom of the hole at all times, adjust the speed and feed volume in time to prevent the disconnection.
5. When the steel pipe passes through the metal tube, complete the hollowing operation.
二， Precautions for seamless steel pipe drilling
1. It is strictly forbidden to use an electric hammer impact method to process the seamless steel pipes with severe cracks; otherwise it will destroy the strength of the steel pipe and affect the service life of the steel pipe. If defects such as cracks, thick skin or scars on the surface of the steel, or have deep local scratches, an electric hammer should also be avoided. (This method is not applicable to seamless steel pipes made from cold pull -up hot -rolled steel plates)
2. Seamless stainless steel pipes used for gas transport, usually using hydraulic pressure tests to check whether its pressure resistance meets the requirements (according to the GB/T12771-2000 standard: 1.5 times the pressure of hydraulic testing is 1.5 times the pressure of the work, the pressure keeping time does not keep the pressure. It is less than 5 seconds).
3. The seamless stainless steel pipe used for hydraulic pillars usually use hydraulic pressure test to check whether its pressure resistance meets the requirements (according to the GB/T12771-2000 standard: 1.15 times the pressure of the nominal pressure; the stabilization time is equivalent Long, 10 seconds).
4. Seamless stainless steel pipes for boilers, with a fluid load, high working temperature, often used as a liquid conveyor tube, and leakage testing is required. (According to the GB/T13396-92 standard: the leakage detection pressure is twice the nominal pressure; the time is 30 minutes.)
5. The high -pressure oil pipes used in high -pressure containers need to be tested. These oil pipes are usually used as pipe pipes. (According to the GB/T14383-93 standard: the leakage detection pressure is 2.5 times the nominal pressure; the time is 1 hour.)
6. As the welding joint is prone to cracks, the effective cross -sectional area of the weld is reduced, resulting in increased leakage, and even catastrophic accidents. Therefore, the welding quality must be strictly controlled.
