翻譯：The HF-HCI mixture (usually 3-percent HF and 12-percent HCI) then is injected. The HF reacts with calys, sand, drilling mud, or cement filtrate to improve permeability near the well-bore.The HCI will not react and is present to keep the PH low, preventing precipitation of HF reaction products. Sent to keep the PH low, preventing precipitation of HF reaction products.

翻譯：The transportation of oil has also led to the spectacular development of gait ships ,the largest ships that ever sailed the oceans of the world .in the last few years ,since it has been necessary to ship oil from middle East-one of the largest oil producing regions-around the cap of Good Hope in south Africa these tanks has grown to almost unblievable proportions.

翻譯：crude petroleum is not an equilibrium mixture, and on a geological time scale its composition is slowly changing. S.R.silverman found that heating at 121C for two weeks caused detectable changes, the low-molecular-weight components formed being isotopically lighter so far as the carbon was concerned, than the original.

翻譯：Gas lift is particularly applicable for lifting wells where high-pressure gas is available.Gas compressors may have been installed for gas injection, or high-pressure gas wells may be nearby. Since the cost of compression far exceeds the cost of down hole gas lift equipment, gas lift always should be considered when an adequate volume of high-pressure gas is available for wells requiring artificial lift. Most wells can be depleted by gas lift,which is particularly true since the implementation of reservoir pressure maintenance programs in most major oil fields.

翻譯：If Colonel Drake, Uncle Billy smith , Anthony Lucas , and the untold thousands of other members of the fraternity of drilling pioneers were alive today , they would no doubt be fascinated and amazed by the proliferation of drilling tools and techniques that have been developed since those primitive days in Pennsylvania and Texas . Undoubltly , they would also be impress by the great numbers of drilling rigs at work today-------over two thousand in the USA alone.