Private Forums
BOP jet sub with integral swab cups (to stop debris falling down the well)
22 October 2016
Dear colleagues

At a recent DWOP, we were discussing the fact that the BOPs (jack-up) would need to be jetted after an exit window has been milled with a cased-hole whipstock. It may be that the bonnets would need to be opened to check all the swarf (metal shavings) have been removed before the Drilling Co would function-test the rams. We would rather not do this.

I have a vague recollection that there is a 'smart tool' with integral swab cups (dressed for the casing size) that you can run. Whilst vigorously jetting the BOP, any swarf that falls into the well will be recovered by the swab cups.

Years ago, when a DSV at Shell, we made our 'own' tool with swab cups to catch a few cap-screws that we knew were either in the (subsea) BOP cavities or sitting on top of a hanger assembly. 

So, please let us know where we could get a 'proper' tools that would do this job.  = Vigorous jetting plus recovery of any debris (in one run). If you have been lucky enough to have run one of these, also any lessons learnt, please.
Supplementary question: Whilst milling, ditch magnets will be in use.  Cleaning the swarf of these is time-consuming and carries HSE swarf (cuts due to the sharp swarf). It was suggested to use cloth 'socks'. However, there was concern that these might fall off and/or collect less metal.  What ideas/experience can you all share, please?



12 answer(s)
Managing Director (
Relentless Pursuit Of Perfection Ltd.
Total Posts: 397
Join Date: 10/01/05
Hi folks,

Here's what the team did..

"The 8” OD Weatherford ClearMax jetting tool worked well even in our 18-⅝” BOP when used with Sea Water and maximum FR (~1200 gpm). On reflection I cannot see that the larger tool (14” OD) would have helped much more for us.

Maybe it would be beneficial in a larger BOP."

I hope that helps.

Kind regards

Senior Drilling Engineer
NRG Well Management Ltd
Total Posts: 17
Join Date: 01/09/15
Hi Dave,
Could you share with us what was the final outcome of the DWOP what measures were finally taken.
Drilling Engineer
Total Posts: 3
Join Date: 29/04/13

We have been running the Archer Tornar tool after milling windows (both for 13-3/8" & 9-5/8" casings exits) for our subsea wells. Typically running the tool 2-3 times until only residual swarf remaining on the magnets to ensure BOPs as clean as possible.

Also run string magnets in the whipstock milling BHAs (either just below BOP or at top of HWDP) as a preventative measure to limit the amount of swarf that can get to the cavities in the first place.

Pete Thomson
Decommissioning Projects Manager
Total Posts: 4
Join Date: 12/12/15

For the 30+ semi-sub section milling jobs we conducted for the HEss abandonments, we used the Coretrax combination Jetting / Magnet tool to clean up the BOP stack

Only the occasional swarf chip was found upon opening up and nothing in the controls side.

As relevant slide won't upload but feel free to contact me if you require more information.

As for ditch magnets, we used several racks of Romar EZ Clean magnets - the racks are made to suit your requirement and the design of the magnet is safe and easy to clean (hence the name I guess!!)

Hope this assists......cheer PT

HPHT Coach
Total Posts: 1
Join Date: 21/10/16

The Patroller is the tool you would need I think.

I have used the SPS patroller many times, the system can be used in many configurations, it is an excellent tool. I have attached some information you might find useful.

Documents uploaded by user:
TU 003 Rev 03 Well Patroller Ops Pages.pdf
Total Posts: 87
Join Date: 10/04/08

There are several generic versions of the old SPS WBCU technology available these days for jetting wellheads and BOPs and catching debris at the same time, one such company is Abrado they also have a clever swirling jetting tool for helping to drag the debris out of the ram cavities and recesses.

Abrado also has a ditch magnet technology, because they just merged with Deltide (fishing/milling company) that is highly effective during milling ops and you don't have to touch the debris to use it and clean it off (patented technique).

Romar have a very well developed product and service for swarf extraction during milling operations supported by highly experienced people.

I am aware of the 5D Magnetics technoIogy too and they also have some interesting new development around steel removal from wells.

I would emphasise that debris extraction and swarf removal are areas to pay particular attention to in high cost wells especially if you plan to run further casing strings, liners or lower completions in the well after after you have exited on a side-track or slot recovery.

Clearly the operator is paying attention to detail ahead of these operations or you would not be doing a DWOP!!
Drilling Supervisor
Total Posts: 2
Join Date: 23/02/16

Hi Dave,

As mentioned most of the main service suppliers provide these cleanup tools all be it with certain nuances . Magnets would be beneficial with a jetting tool that is nozzled to provided various flow angles. 

The Tornar by Archer is one that I have come across that is different to others (or just better marketing) and has been utilised for some heavy cleanups here in Norway.

Having magnets in the BHA that are ribbed are beneficial for cleaning similar to ones used by MI.



Total Posts: 2
Join Date: 05/03/08

Hi Dave,

 All of the major suppliers of wellbore cleanup tools (MISwaco, BHI, Halliburton) plus the smaller suppliers (such as Odjfell, Archer etc) should be able to supply this without issue. 

Not so sure about a single tool with integral swab cups but they all have tools under names similar to “surface junk catcher” which you can run below a BOP jetting tool. 

The ”surface junk catcher” will have a swab cup, or tight interference fit part (depending on supplier and relevant patents) that contacts the casing. 

For efficiency you can have the assembly made up in the workshop prior to delivery to the rigsite. We ran this assembly regularly on the BP Tangguh phase 1 project (which you may be familiar with through the Technical Limit coaching contract that you had there). 

If it is a milling operation and swarf is the concern I would supplement the BHA with some string magnets.

Also may be worth looking at the openholenet by 5D magnetics (

 In reference to your comment on the use of ditch magnets, 5D also have a magnetic flowline filter and Romar have Magnogrid and EX-clean ditch magnets which should resolve the issues of cleaning swarf without the use of socks. (



[email protected]
Drilling Consultant
Total Posts: 21
Join Date: 08/01/16
I would recommend using BOP jetting tool, junk sub and magnet at the bottom.

You can use jetting tool from wellbore specialties which enable you to drop the ball to activate the jetting ports and drop the second ball to deactivate the ports. Once the swarfs fall down, they get caught by junk sub or the magnet. With the option of closing the ports by using the second ball you can try to catch as many debris as possible in the junk sub.

I've asked an experienced fisherman and will get back to you with his comments after the weekend.

Drilling Consultant
Total Posts: 6
Join Date: 26/02/16

I too have had a good success with the well Patroller - also, use a couple of string magnets.

On the subject of magnets - I have had good experience with Romar magnets - these are finger magnets and can be supplied with a pull-to-clean sleeve which allows you to pick them out of flowline and simply pull a handle and the swarf falls into a bucket. These should be sufficient for a simple window-mill.

I'd steer clear of the big 56 lb magnets which are difficult to handle - you can probably still put one in the flowline downstream of the Romar ones just in case, but they are a pain to clean.

Drilling Manager
Total Posts: 4
Join Date: 06/11/14
Neil is right, we used Well Patroller several times and it is designed for this kind of job.
Best regards
Drilling Supervisor
Total Posts: 55
Join Date: 11/09/10
Try the Well Patroller from Schlumberger (tool originally developed by SPS, them bought by MI Swaco).

Seen it used a lot for wellbore clean ups prior to completion.
Run the patroller so that it is a stand below the BOP when you use your jetting tool.


Jump to top of the page