Most oil well cement slurries will be added to some additives in order to modify cement properties so cement operation can be properly performed. In this article, it will cover some of important cement additives in general terms so that it will help you understand the basic function of each additive.
Accelerators are added to shorten the time for cement to properly set and it will reduce rig time while waiting on the cement (WOC). Accelerators are crucial in shallow depths where bottom temperature is low. In the deeper section, it may not require an accelerator, because the well is hot enough and the thickening time will be normal. The WOC time is generally based on the time required to obtain 500 psi compressive strength of the cement.
Chemical used as accelerators are as follows;
Calcium chloride 1.5 – 2.0 %
Sodium chloride 2.0 – 2.5%
If the percentage of these additives is high, they will act as retarders instead of accelerators. Continue reading →
The well is in an underbalanced condition while pulling out of hole. You can see in the video below that the fluid is flowing up from the drill pipe side. It is such very important to understand the condition of the well and have the plan to deal with it.
These are some thought about this situation from our member in the Facebook fanpage.
Hossam Hamza – Looks like it was failed balanced cement plug job, I see long cement chiksan line on rig floor and circulating head connected with low TQ valve above 1 joint DP in mouse hole, the back flow due to over displacement. Is my guess right???? Continue reading →
One of my friends shares this slide, An Introduction to Oil & Gas Drilling and Well Operations. This slide is the educational material from the IOM3 Oil and Gas Division, UK (http://www.iom3.org/). This is show all the basic of drilling and well operation in very simple language term. Additionally, there are several images which help explain content in this document clearly. This is a very good document when you try to explain overall drilling and well operation to new team members who don’t have much oilfield experience. The subjects covered in this presentation are as follow;
•Why we drill wells
•The well life cycle
−Well design and construction
−Pipe handling and the drill string
−Drilling and drill bits
−Cementing (including plugging and abandonment)
•Well testing and evaluation
Have you ever imagined about the down hole conditions of oil and gas wells?
We initially think that they might look pretty smooth tubular with perforated holes and down hole tools. Until we’ve seen these footage, you will be amazed how the technology can help you to look into down hole. They are excellent VDOs because they demonstrate the well conditions in various situations. You can see down hole tools (packer, side pocket mandrel, etc), perforated holes, damaged casing, hole shape, tubular conditions, etc. What’s more, down hole camera can demonstrate how oil and gas wells produce. With this application, it will help oil companies to identify the well production issue more accurately. Continue reading →