November 14th, 2013 MILFORD, Texas -Hundreds of people in Ellis County were evacuated and others were asked to stay away from the area where a gas pipeline caught fire Thursday morning.
It happened at about 9:30 a.m. November 14th, 2013 near the intersection of Highway 77 and FM 308 in Milford.
Ellis County spokesman James Saulter said a Chevron crew had been conducting a type of drilling when the explosion happened.
Drillpipe is seamless steel pipe made up in the drill string and it is the major component of the entire drillstring. Typically, 90% – 95% of the total length is drill pipe. Thread connection of drill pipe is called “Tool Joint”. One end of drill pipe has a female end which is named as “Box” (see Figure 1).
Figure 1 – Box End of Tool Joint
Two types of stabbing valves that must be prepared for well control are Full Opening Safety Valve (TIW valve) and Inside BOP valve (Gray Valve). We would like to describe what the differences between two valves are.
Full Opening Safety Valve or TIW valve is a ball valve designed for high pressure condition and it can hold pressure from both directions. It is called “Full Opening” because when the ball valve is opened; the flow path through the valve has a smooth inside diameter. One thing that you need to remember is that the term “Full Opening” does not mean that the ID of the valve is the same of drill pipe ID. ID of the valve is typically smaller than the pipe in the hole.
Figure 1 Full Opening Safety Valve
Frictional pressure is pressure loss acting in the opposite direction of fluid flow and today we will look into each component in pressure therefore you will get clearer picture about the frictional pressure in drilling system.
Let take a look at the simple diagram below.
A mud pump creates power to move drilling fluid from point A to C and the frictional pressure or pressure loss is the amount of pressure required to transfer fluid.
Pump pressure is 2,000 psi at the starting point (“A”) and at the end point (“C”), pressure is 0 psi. This tells you that you need 2,000 psi to overcome the frictional pressure in order to move the fluid from point “A” to point “C”.
“Differential pressure between two points in the system is pressure loss while fluid is moved from one to another point.”
There are not many books about drilling bits in the market. Today, I would like to share with you about this book, “The Bit” which is a very good book in the rotary drilling series.
The book is written in a simple language therefore everyone can understand this topic so easy.
