1. Outer barrels are made of high-strength thick-wall seamless steel tubes, and equipped with multiple stabilizers, which make it high strength, high rigidity, and help to improve core recovery as well as elongate working life of diamond coring bits.
2. In addition to steel inner barrel, others made of fiberglass, aluminum alloy and stainless steel are also available, which are light, temperature-resistant, abrasion-resisture, high strength and smooth inner wall. Small resisting force when core entering inner barrel is advantageous for improving core recovery when coring in unconsolidated or broken formation.
3. The length of inner barrel equals to outer barrel which is 9.20m, and operator can get different length of core barrels at will. Because of inner barrel being in outer barrel, both of them will be lifted together which can save much more assembling time.
4. The surface of stabilizer has been welded with carbide and polished, which eliminate holes on the surface, so make it being good abrasion resistance and small torque.
5. When coring barrel gets stuck downhole, it is very easy to back off at safety joint to trip out inner barrel and cores, and only left outer barrel for fishing operation.
6. 5 kinds of core catchers have been designed for different formations.
7. Complete auxiliary tools make it more simple to core and more time to be saved, especially when using in costly areas such as offshore operations.
8. Chuan-5/6 coring tool is the upgraded product of Chuan-4, whose swivel assembly has been equipped with automatic relieving installation, which allows bypass valve and check valve installed on drilling assembly when coring in high pressure hydrocarbon reservoir. Meanwhile it can prevent mandrel from damage by high density drilling fluid, and improve the integral strength of the rotating assembly.
9. The high-strength thread replaces the standard thread of ordinary conventional coring tool, the maximum torque is 2.5 times more than that of the conventional coring tool under the same conditions, the fatigue life of thread is times that of the ordinary conventional coring tool.
