· Difference of the thread structure (datum mark-All products);
· Difference ofhardness test position (NS-1 increase full cross section hardness test-all products);
·Cold rolling requirements (the clear requirements of the thread and stress-reducing groove for cold rolling treatment, and drill collar hanging cards, slips root fillet of the rolling requirementsinNS-1-all products);
· The difference of impact work (part of the product requirements under low temperature -20℃ conditions test of NS-1 );
· The difference of wall thickness difference (The requirement of full length wall thickness difference and both ends wall thickness difference in NS-1 );
· Product marking groove type and position requirements;
· Requirements for specific dimensions of wear-resistant belt welding type;
· Other recommended requirements.
Possible causes: motor stall, motor drive shaft card dead, or bit plugged blocked...
According to the vibration-knocking tool and structure ,is hydraulic and mechanical in terms of its structure....
· Difference of the thread structure (datum mark-All products); · Difference ofhardness test position (NS-1 increase full cross section hardness test-all pr...
The diameter of the drilling device is worn out, and the outside diameter of the inner whorl is expanded larger than the following table, and shall be scrapped...
была образована в 2010 году, Основная продукция компании: утяжеленые бурильные трубы, веду...
根据经济参考报报道,加强农村基础设施建设将成为未来一段时期实施乡村振兴战略的一项重要工作。我国将围绕农村的物流...