Increase In Leaning BOP By Up To 1.5 Degress Appears To Confirm BP Gulf Oil Spill BOP Is Falling Over (Update 5)

Posted by Alexander Higgins - June 28, 2010 at 11:46 pm - Permalink - Source via Alexander Higgins Blog

June 28th Bullseye Reading Shows Increase In BOP Lean To Over 4 Degrees Since June 10th Reading Which Showed Lean Of Less Than 3 Degrees

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I originally wrote that the subsea bullseye measurements taken on June 10th indicated that the BP Gulf Oil Spill BOP was leaning 3 degrees.

Just to be clear, the post above shows that the BOP appears to be leaning about 11 degrees on camera, but the original reading subsea bullseye indicate a lean of a little under 3 degrees was confirmed by the manufacturer of the subsea bullseye which is included in an update on that post.

Since then there has been a great deal of speculation that the lean of the BOP could mean the that BOP is falling over.

That speculation went viral and even made mainstream media news reports.

But the speculation couldn’t be confirmed because there where no past reading to compare the lean to.

Now there is.

The latest bullseye readings taken show that tilt of the leaning oil well has increased by up to 1.5 degrees and appears to confirm that the BP Gulf Oil Spill BOP is indeed falling over.

Bottom Bullseye Readings Show Change Of ~.75 degree

Left shows June 10th Reading of over ~2.5 degrees and right (Posted June 18th by unknown) shows lean of little less than ~2 degrees- About ~.75 degree change

Middle Bullseye Readings Show Change of ~1.5 Degrees

Left taken June 15th shows lean of ~1.25 degrees and right taken June 28th shows lean of ~2.75 degrees a change of about 1.5 degrees

June 28th Subsea Bullseye Reading Shows Lean of over 4 degrees

Today a reader of my blog posted a clear video of an updated bullseye reading.

June 28th Bullseye Reading Shows Increase In BOP Lean To Over 4 Degrees

Video Of the June 28th Bullseye Reading

This indicates the BOP is falling over as speculated in widespread rumors on the internet.

In fact the BOP lean has increased by approximately 1.5 degrees since the June 15th subsea bullseye reading.

Tuesday, June 29th 2010
NOLA.com has reported that BP has confirmed the BOP is in fact leaning.

Oil Spill containment efforts could be putting strain on damaged well

Meanwhile, observers monitoring the video feeds from the robotic vehicles working on the sea floor have noticed BP measuring a tilt in the 40-ton blowout preventer stack with a level and a device called an inclinometer.

Odone, the BP spokesman, confirmed that his company has been monitoring the lean of the blowout preventer, which BP believes began tilting when the Deepwater Horizon rig sank and the riser pipe got bent. “That is tilting and has been tilting since the rig went down,” Odone said. “We believe that it was caused by the collapse of the riser.”

Since the confirmation from BP that BOP is leaning the unanswered questions have been how much did the initial collapse cause the BOP to lean and is the lean increasing?

The first question still remains unanswered but we now have confirmation of a change in the lean by up to 1.5 degrees.

That does not however provide absolute proof that the BOP will fall over entirely but it shows that it is indeed falling over.

Some have commented that the Bullseyes are mounted on swivel joints which tend to swing several degrees.

To me however, it makes no sense to me that BP would install a level on such a joint that could swing a few degrees knowing that the BOP was leaning and that the limit of the bullseye level was only up to 5 degrees.

It would also not make sense for BP to come back later to clean it and then measure the level again knowing the measurement would not provide an accurate measurement to any degree of certainty.

June 29th, 2010 6:55 PM

Addressing the FlexJoint Issue

I initially incorrectly assumed that the difference between the top bullseye level could be compared to the middle bullseye level to give an accurate measurement of the lean of the BOP.

My assumption was incorrect because I assumed that the top bullseye was mounted to the top of the Flex Joint which it appears to be due to an optical illusion caused from lack of depth perception on the ROV screens.

The optical illusion gives the appearance that the top bullseye is mounted directly to the top of the flex joint when it is in fact mounted to the side of the pipe on the bottom of the riser adapter coming out of the top of the Flex Joint.

The mistaken assumption still does not refute the lean of the BOP itself has changed which is evidenced by the difference in lean of the BOP measured on the bottom bullseye and is also evidenced by the change in the lean of the BOP measured by the middle bullseye.

It does mean that the top and middle bullseye can not be compared to one another to measure the a change in title in the BOP.

My mistaken assumption was corrected as follows.

A comment, caught up in the spam filter pointed to a diagram of the BOP.

Diagram of the Top of the BOP

From that that diagram and this angle of the cleaning of the top bullseye as well as the diagram below posted online, I assumed that the diagram below correctly pointed to the mounting location of the bullseye.

Cleaning of Top Bullseye For June 28th Lean Measurement

INCORRECT Diagram of Subsea Bullseye Mounting Locations – Top and Middle Locations – Posted elsewhere online

Diagram courtesy of aethervox – Note original diagram did not have correction

Based on that information I rebutted comments stating that since the top bullseye was mounted on the flex joint where it could swivel it could not be used to measure the tilt of the BOP by comparing it to the middle bullseye.

My rebuttal was based on the following basis with data collection from the FlexJoint manufacturer.

Clearly as the comment indicated that the bullesye is indeed attached to a flex joint.

However, it still appears that intuition would lead one to assume that BP would not attach a level to the flex joint where it would provide inaccurate measurements is correct. What the other comments fail to indicate is that the Flex Joint Casing itself, which is attached to the top of BOP, does not swivel but allows the riser adapter coming out of the the Flex Joint to swivel.

In fact the swivel/flext joint itself is a solid forged cast of metal that is bolted to the LMRP and does not swivel.

Here is a cut out of the the flex joint showing it is one solid piece.

That image was taken from the oilstates.com Flexjoint.pdf which states:

The FlexJoint is composed of a large-diameter spherical elastromeric element inside of a forged housing (meaning it is a solid piece of metal), with customer-specified end connectors. When installed at the top and/or bottom terminations of a riser system, the FlexJoint allows for large angular deflections (of the riser – not the BOP or the FlexJoint) and accommodates all loads and motion even during severe storms.

To understand what is meant by the “elastromeric element inside of a forged housing” we refere to diagram of the inner workings of the FlexJoint below clearly shows the elastrometric element inside of the flex joint, marked orange, which allows the riser connector to swivel.

Responding to another comment that said read the specs, I replied “The specs read:”

Elastor Element: In addition to accommodating angular displacement, the elastomer element assembly retains interal pressures and tensions and transfers to both compressive loads in the elastomer layers. Angular movement is accomplished trough pure shear which is distrubuted in each elastomer layer. Shear and compressions stresses in each elastomer bonded layer are distrubuted by the steel reinforcement.

Again referring to the diagram above the Elastor element is located inside of the housing and allows the shaft inside of the FlexJoint to move, not the FlexJoint housing itself which is where the Bullseye is mounted.

The solid casing is forged metal and does not tilt to any degree except in the case that the BOP it is bolted on to tilts.

This invalidates the argument that the bullseye level can naturally be off a few degrees because it is on a flex joint.

Anyone familiar with the inner workings of this particular FlexJoint knows it allows the shaft or riser connector to move inside of the casing.

This clearly means that it is the riser adapter coming out of the top of the flex joint is free to swivel several degrees and not the flex joint itself.

Again this is a solid casing. The lean allowed for the riser comes from the elastromeric element inside of the casing which is designed to allow the riser shaft to move.

This graphic is reported to show the relative distance of the two bullseyes being measured.

Picture capture by aethervox

When BP installed the bullseyes about a month ago it is most likely that bullseyes had the same exact tilt of zero degrees at that time and is unlikely that there measurements where different by 1.5 degrees when first installed.

It was then verified that the flex joint does allow for tilt as as explained above which is consistent with my rebuttal with the bullseye mounted as shown below and is further explained by the following.

Flex Joint Movement Diagrams

Flex Joint Movement Locations and Top Bullseye on the Leaning BOP

However as stated previously the mounting location of the top bullseye that I assumed was wrong in the above “incorrect diagram” meaning that my assumption that the top and middle bullseyes measurements could be compared to one another for a gauge of BOP tilt was incorrect.

In fact, the correct mounting location for the top bullseye is shown in this picture.

Top of BOP with Bullseye Location Marked Screen Shot