Compared with the same period last year, the output of seamless steel pipes has an upward trend. The first quarter increased by 8.56% and the second quarter increased by 10.58%. Therefore, in the second half of the year, attention should be paid to preventing the total production of seamless steel pipes from growing too fast.
First, the method of drilling seamless steel pipes
1. Use a special perforator to drill the inner diameter of the steel pipe to the required specifications. Before drilling, check whether the pipe has cracks, folds, severe rust, and other defects. If there are any defects, they must be removed before drilling.
2. Select the corresponding drill bit on the perforator according to the required specifications of the steel pipe (generally a diamond-beaded electric drill bit with a diameter of 32mm or 40mm), and then adjust the appropriate speed and feed amount before drilling.
3. When the wall thickness of the steel pipe is less than 4mm, a small-diameter diamond beaded electric drill bit can be selected; if the wall thickness is greater than 4mm, a large-diameter diamond beaded electric drill bit (such as Φ50) should be used.
4. During the drilling process, pay attention to the bottom of the hole at any time and adjust the rotation speed and feed rate in time to prevent wire breakage.
5. When the steel pipe passes through the metal casing, the hole-piercing operation is completed.
Second, precautions for seamless steel pipe drilling
1. It is strictly forbidden to use the electric hammer impact method to process and perforate seamless steel pipes with severe cracks; otherwise, the strength of the steel pipe will be damaged and the service life will be affected. If cracks, heavy skin, or scars are found on the surface of the steel, as well as deep scratches in some parts, the electric hammer processing method should also be avoided. (This method is even more inappropriate for seamless steel pipes made of hot-rolled steel plates cold-drawn)
2. For seamless stainless steel pipes used for gas transportation, a water pressure test is usually used to check whether their pressure resistance meets the requirements (according to the standard GB/T12771-2000: the water pressure test pressure is 1.5 times the working pressure, and the pressure holding time is not less than 5 seconds).
3. For seamless stainless steel pipes used for hydraulic props, hydraulic tests are usually used to check whether their pressure resistance meets the requirements (according to the standard GB/T12771-2000: the hydraulic test pressure is 1.15 times the nominal pressure; the pressure stabilization time is not less than 10 seconds).
4. For seamless stainless steel pipes for boilers that bear fluid loads and have high working temperatures, leakage detection is required when they are often used as liquid delivery pipelines. (According to the standard GB/T13396-92: the leakage detection pressure is 2 times the nominal pressure; the time is 30 minutes.)
5. For high-pressure oil pipes used in high-pressure containers, leakage detection is required when they are often used as gas delivery pipelines. (According to the standard GB/T14383-93: the leakage detection pressure is 2.5 times the nominal pressure; the time is 1 hour.)
6. Since cracks are easily generated at the welded joints, the effective cross-sectional area of the weld is reduced, which causes increased leakage and even catastrophic accidents. Therefore, the welding quality must be strictly controlled.
Post time: May-20-2025