What are the key points for drilling and drilling?
Before the rig is in place, the drilling preparations should be checked. The base and top of the rig should be stable after installation, and there should be no displacement or subsidence during drilling. After the position is completed, the construction team will take the self-inspection on the rig. Before drilling, according to the geological and hydrological data provided by the construction design, different drill bits, drilling pressure, drilling speed and appropriate mud weight are selected for different geological layers. The rig is in place and should not be displaced or sunken during drilling and operation. The drill pipe should be vertical, and the center of the rotary cylinder should be aligned with the center of the pile. Use low-speed slow drilling when drilling, drill 1m below the casing and then drill at normal speed. After the rig is lifted and the slag is reset during the drilling process, the drill should be inspected for alignment. In the initial stage of the drilling rig, when the bucket is lifted, the hole wall is not constricted due to the phenomenon of “suction drilling†caused by the large negative pressure generated in the lower part of the bucket, and the wall of the cylinder of the drum is symmetrically welded. Or add a diversion channel) to improve to reduce the occurrence of borehole necking. Drilling operations should be carried out continuously in sections, drilled in sand clay and sand, and directly drilled into holes and slag. Drilling in the gravel and sand pebble layer should first loosen it with a spiral drill bit, and then use the rotary digging cylinder to take the slag. Strictly control the drilling speed, when the lifting speed of the drilling bucket is too fast, it will easily cause necking and collapse of the hole wall. The lifting speed of the bucket should be controlled at 0.75-0.80 m/s. When the sand layer or the sub-soil layer is used, the lifting speed of the bucket should be slower. During the drilling process, the mud surface should not be lower than 500mm above the bottom of the casing to ensure the stability of the hole wall. To measure the drilling depth, the weight of the rope (1~2kg) is measured from the bottom of the rope to the top of the casing. The drilling mud and the rig should be inspected frequently. If it does not meet the requirements, it should be corrected in time. Attention should be paid to the change of the formation, and the slag sample should be preserved at the change of the formation. During the drilling process, the change of the location of the host and the support of the foot should be observed, and the settlement phenomenon should be stopped in time. If the downtime is long, the protection measures for the hole pile and the drilling rig should be done. After drilling to the design elevation, the time for taking the slag from the rotary boring cylinder is relatively extended, so that the drilling slag can be taken away, but it cannot be pressurized to avoid over-drilling. When the drilling depth reaches the design requirements, the hole depth, the hole diameter, the hole position and the hole shape are checked by means of a hole detector and a measuring rope. After confirming that the design requirements are met, the final hole inspection certificate is filled out immediately and the resident supervision is carried out. Engineers are approved to prepare for bottom hole cleaning and pouring underwater concrete. When the full casing is used to follow up the hole, the mud wall can be omitted. China Deep Hole Drill Trading Network is an e-commerce platform dedicated to deep hole drilling rigs under the China Net Library. It concentrates on all the upstream and downstream enterprises in the country for genuine purchase and genuine wholesale. To provide consumers with a professional deep hole drilling machine trading platform and information, with a wealth of deep hole drilling rig resources, fundamentally can guarantee the quality of deep hole drilling rig. So if you want to pay more attention to the knowledge of deep hole drilling rigs, please come here! The above information comes from China Deep Hole Drilling Machine Trading Network: http://skzj.99114.com From a beautiful design to showcase your collection to a handy leather roll to slip inside your hand luggage, no serious timepiece connoisseur should be without a luxury watch box. Whether you want a pocket-sized roll to protect your top worldtimer on business trips or a larger box to keep all your classic sailing watches in one place, our edit of the best luxury watch boxes has something for everyone. Watch Box,Single Watch Box,Watch Jewelry Box,Watch Box Organizer Shenyang Meitu Artical Printing Co.,Ltd , https://www.meituprinting.com