简答题 翻译：There are special types of valves designed to be operated by control instrument rather than by hand.

翻译：Exploration methods falling in this category are tho...

问答题翻译：Exploration methods falling in this category are those employing a physical measurement of subsurface conditions made from a surface location.

翻译：Water and acid gases are removed from the wellhead g...

问答题翻译：Water and acid gases are removed from the wellhead gas stream because they can cause corrosion and other problems in long distance pipeline and associated equipment.

翻译：Also specified in gas purchase contracts is the maxi...

问答题翻译：Also specified in gas purchase contracts is the maximum amour of sulfur the sales gas may contain.