Today's picture was taken in the Seminole Oil Field in Oklahoma in 1939. It shows another shot of roughnecks "making a connection". You can see the top of the old piece of drill stem sticking up from the round disk, which his the rotary platform. This is the long drill string that goes way down in the ground. You can see drilling mud flowing out of the top of the drill string. The roughnecks are adding another 30 foot section of drill stem to the string. I mentioned yesterday that large tongs are used to tighten the bottom of the new piece of drill stem into the top of the drill string going down into the well. It would take too long to screw the new piece in this way . . . the tongs are just used to tighten it the last few inches. To get the stem screwed in most of the way, a cable or chain is "thrown" around the new drill stem to make it wrap around a make a coil, as seen in the picture above, The other end of the cable is connected to a motor, and the driller activates the motor to pull the cable. This screws the drill stem into the drill string. You can see the roughneck holds the opposite end of the cable. This is very dangerous, as there is a tendency for his hand to be pulled into the drill stem. This is one of the common ways roughnecks lose fingers.
Drilling is a lot safer now than it was back in the day, but it is still a very dangerous job . . . probably among the most dangerous jobs in the world. You can see that there are many ways to lose fingers. Besides the cable pulling a hand into the wrapped coil, when the new drill stem is placed onto the drill string, it is lifted by the Kelly, which is controlled by the driller. If a roughneck puts his fingers under the drill stem to try and help get it aligned with the drill string, and the driller then drops it into position, the roughnecks fingers are cut off. Also, all types of ways to get the fingers smashed in the big tongs. There is a lot going on overhead. One roughneck is the "derrick man" and he works up on top of the rig, helping to get the drill stem aligned from the top side. He is about three to five stories up, and has all types of tools. It is easy for something to get dropped from his work area down onto the roughnecks below. In addition, rigs use a lot of very high pressure air, which is routed around in large high pressure hoses. The hoses are lined with steel windings. These hoses degrade from the inside out, and eventually they fail, and blow up, throwing shrapnel worse than a hand grenade. Another way people get hurt of killed is with the chains and cables running from the driller's motors to the drill stem. When not in use, the chains and cables lay on the rig floor. When the driller activates them, they pop up into the air very quickly. If a roughneck is walking along the rig floor and is stepping over a chain or cable when the driller pops it, it comes up and can literally split a roughneck in two. There are a lot of high voltage lines running around to lights and equipment, so electrocution is a big risk. Then, when you are drilling, there is always a chance of drilling into a gas pocket, and then natural gas comes out of the top of the drill string when making a connection. This is easily ignited, causing a blowout. Modern rigs have blowout preventers, but they do not always work.
So, working on a rig is dangerous business. Someone asked yesterday if I was a petroleum engineer . . . no, I am an electrical engineer, but I worked on oil rigs in the summers when going through college.