Optimized Selection and Scientific Maintenance of Wear-resistant Parts of Rotary Drilling Rig Effectively Improve the Service Life of Equipment

The selection of suitable working condition is the core basis for the life extension of wear-resistant parts

As the core wear-resistant component, the drill bucket, gear seat and casing of rotary drilling rig directly contact with the complex construction media such as rock and soil and sand. The wear loss is the main cause of equipment failure and construction shutdown. The suitability of model selection directly determines the service life of component foundation. Different geological conditions have great difference in the performance requirements of wear-resistant parts, and conventional wear-resistant material drilling bucket can be selected for soft soil and sludge strata, taking toughness and economical efficiency into consideration; The high-strength alloy wear-resistant drilling bucket shall be used under complex and severe working conditions such as pebbles, rocks and hard soil layers, and the thickened wear-resistant plate shall be used to reinforce the structure. The gear seat shall be selected according to the drill model. Products with uniform wear-resistant layer and one-piece forging are preferred to avoid cracking, tooth loss and rapid wear of welded poor gear seat. Standard components with uniform wall thickness, extrusion resistance and abrasion resistance shall be selected for the pile casing according to the bore diameter and construction depth, so as to eliminate deformation and abrasion aggravation of thin non-standard pile casing during deep burying and compression construction and reduce component loss from the source.

Key points of special type selection of drilling bucket and fine protection logic

Drill bucket is the most frequently worn core component of rotary drilling rig, which undertakes the main cutting and slag tapping operations. Selection and protection optimization are very important to reduce the loss and extend the life. The construction enterprises shall abandon the thinking of unified type selection and combine the construction process to match the drill bucket structure. The cutter wear-resistant drill bucket shall be preferred for rotary excavation drilling of hard rock stratum. The tooth head has high hardness and strong impact resistance, which can reduce cutting wear; Sand salvaging wear-resistant drilling bucket can be selected for backfill soil layer construction to improve operation efficiency and reduce useless loss. In daily use, it is necessary to repair the wear-resistant layer and replace the worn tooth head in time according to the wear state, so as to avoid the scrapping of the entire drilling bucket due to local excessive wear. At the same time, the drilling speed and pressure degree shall be strictly controlled to eliminate the falling off of the wear-resistant layer and structural deformation of the drill bucket caused by violent construction, and greatly extend the continuous service period of the drill bucket.

Precision adaptation of gear seat and normal maintenance and loss reduction skills

As the key part for fixing the drill bit and transmitting drilling power, the gear seat is small, but its wear, looseness and failure will directly affect the drilling efficiency and increase the loss of the drill bucket. Attention shall be paid to the material hardness, welding accuracy and adaptability of gear seat during type selection. High-chrome alloy gear seat shall be preferred, which has strong abrasion resistance and impact resistance and is suitable for various complicated geotechnical construction scenes. In daily operation and maintenance, it is necessary to establish a normal patrol inspection mechanism, check the fastening state of the gear seat before and after each construction, and timely clean the sand-gravel debris between the gaps to avoid abrasion caused by friction of hard particles. The slightly worn gear seat can be reinforced and welded in time. The severely worn, loose and deformed gear seat shall be replaced immediately to prevent gear loss and eccentric wear during construction, ensure the stable operation of the whole set of drilling components and reduce the overall loss cost.

Pile casing specification selection and key measures for construction and maintenance

The pile casing is mainly used to protect the wall, prevent collapse and calibrate the hole diameter. It rubs and extrudes with the soil layer and sand for a long time, so it is easy to cause problems such as outer wall abrasion, end deformation and pipe wall damage. Compliance standards shall be adhered to in the selection stage. Conventional carbon steel casing can be selected for municipal shallow hole construction, and thickened wear-resistant casing must be selected for deep hole and rock stratum construction to improve the anti-extrusion and anti-abrasion capacity. During the construction process, the burying and pulling out process of the casing shall be standardized to avoid the damage of the wear-resistant layer on the outer wall of the casing and deformation of the end caused by forced knocking and dragging. Upon the completion of construction, mud and hardened sand and stones on the surface of the casing shall be cleaned in time, and the worn and scratched parts shall be subject to anti-corrosion repair welding. During storage, the casing shall be leveled to avoid extrusion deformation, corrosion and wear, and effectively extend the repeated service life of the casing.

Systemic operation and maintenance management and control to realize long-term loss reduction and life extension

Life improvement of wear-resistant parts of rotary drilling rig is not a single part optimization, but a result of systematic control of model selection, construction and maintenance process. The construction enterprise shall establish the grading and selection standard of accessories, and formulate the special wear-resistant parts selection scheme according to the project geology and construction conditions to eliminate blind selection and mixed use of accessories. At the same time, standardize the construction habits of operators, strictly control illegal operations such as violent drilling and overload operation, and reduce the abnormal wear of components from the construction process. Establish equipment regular maintenance account, and record the wear degree, service period and maintenance of drilling bucket, gear seat and casing in the whole process, so as to realize wear pre-judgment, advance maintenance and timely replacement. Through model selection optimization and scientific operation and maintenance, the service life of wear-resistant parts can be greatly improved, the operation and maintenance cost of equipment can be reduced, the equipment failure shutdown can be effectively reduced, and the overall efficiency and stability of rotary excavation construction can be improved.