Quaise is also aiming for faster drilling not just longer lasting drills.

Anyway, seems like the obvious solution is to stack multiple drill bits at the end and detach ones that get used up. Obviously this doesn’t work, but it’s not clear to me why it shouldn’t.

Well, where are the used up drill bits supposed to go to in a hole just as wide as the bits itself except for up and out?

Again going for obvious solution, drop it, back up a few meters and drill around.

Alternatively, have pre drilled side paths for drill bit drop off.

How do you pre-drill side paths ? Isn't being able to drill the hard part ? I am not saying it's dumb but from what I know about the industry (almost nothing) it does not seem simple at all

They need to be able to steer drills for all kinds of reasons: https://www.youtube.com/watch?v=JAhdb7dKQpU

Actual answer seems to be drilling side holes also involves removing the pipe. https://news.ycombinator.com/item?id=43371776

The drill is on the end of what amounts to a several km long rope. I’m pretty sure a side hole would introduce friction with the side that wasn’t there before, making it easy to stick going in and out. I think if the obvious solution worked then people would already be doing it, cause they’d save multiple millions of dollars.

They can do side drills, but apparently that also requires removing the pipe which is the bit I was missing.

https://news.ycombinator.com/item?id=43371776

Ah yep that does explain it well.

Why don’t they just retract the bits and change them like I would on a regular drill that needs a new bit?

Is the failure mode they always or often fall off the shank into the hole and they can’t be extracted?

That's exactly what they do. It just takes a while since there's tens of thousands of feet of drillstring.

Then what’s the jive about needing to drill around the old bits?

Removing many miles of pipe to swap out a drill bit at the end is slow and seems rather inefficient.

Which suggests just leaving the old drill bit somewhere in the ground. But currently doing that would also involve removing the pipe, as to why: https://news.ycombinator.com/item?id=43371776

That was answering silly speculation about intentionally leaving worn-out drill bits behind. There are actually workable procedures for drilling around things, but it's far more cumbersome and time-consuming than replacing a bit normally. Those procedures used for things like the drillstring getting stuck due to hole collapse; nobody would do that just for a worn-out drill bit.

The actual way to avoid the problem is by using bits whose design lifetime in the formation you're drilling is at least as long as the hole section you're planning to drill.

Main reason it wouldn't work is that once a bit is lost in the bottom of the hole, that portion of hole is done, el fin. These bits are diamond impregnated PDC bits and you cannot drill or mill through them. Once you've dropped one, it would be a required side track.

Now you might ask, cool so just drill around it.

The problem is that with current technology, you HAVE to pull back to the surface first in order to do this. You need to cement the bottom of the current hole and depending on the circumstances, you also need to set a 'whipstock' in order to assist in drilling out of the original hole. Side tracking is a long and arduous process that involves numerous trips out of the hole.

So regarding your lower comment, that's why we can't just have multiple bits and drill around them, or drop them off in their own sidetrack. It's not a bad idea, it's just that the realities of drilling at these depths are harsh and not completely intuitive.

My Creds - currently in the gulf of mexico drilling a well with a total depth of 30,012 feet.

On a recent podcast, I believe the founder said that at 6 miles (close to your 30k well) that this technology could be used anywhere. However, I think they could only get 3-4 mile wells at this point. So if we already have the ability to drill 6 miles with conventional tech, why not just do geothermal with conventional drilling?

The technology being discussed hasn't actually drilled much of anything yet. Their latest press release with actual numbers[0] gives depths drilled in inches. Nice progress, yeah, but they're not anywhere near competitive with even water wells, much less the current generation of conventional oilfield drilling technology.

Geothermal power is indeed cool, but to get it usable anywhere on Earth instead of a few places where magma currents happen to be near the surface, we'll probably need several orders of magnitude deeper and wider holes than we're currently capable of drilling just for starters. Can these guys do the job? Maybe, but let's just say I'm not planning to invest in them.

[0] https://www.quaise.energy/news/from-lab-to-field-testing

> The technology being discussed hasn't actually drilled much of anything yet. Their latest press release with actual numbers[0] gives depths drilled in inches.

That's what bothers me about this. If drilling with microwaves works, why aren't there industrial applications? Laser cutters are widely used, from little ones that engrave plastic to big ones that cut steel plate. Yet nobody seems to be selling microwave cutters. In industrial applications, you don't even have to fit the microwave generator into the hole and keep it working in a hostile environment.

The idea was suggested back in 2002, but seems to have gone nowhere.

[1] https://www.researchgate.net/publication/11075717_The_Microw...

Microwaves are a longer wavelength of light which makes them less precise. So people don’t use them to cut stuff for the reason lithography swapped to ultra violet light.

This wants to dump a lot of heat into a large area, and there’s industrial uses for that: https://industrialmicrowave.com/industrial-microwave-heating...

You also have a device at home that uses microwaves for heating larger volumes of material…

My understanding from earlier encounters with reporting about this company, is not that we can't do geothermal drilling without it, it's that it's not always cost-effective. Drilling is expensive and the cost is a significant fraction of the total capital investment in a geothermal energy plant. In order to make geothermal cost effective everywhere, drilling needs to be made less expensive. This company is not about doing what is currently impossible, it's about doing what is currently possible cheaper

He is probably on a rig drilling a deviated well to 30k+ total depth (TD) so that it is not a vertical well 30k+ feet deep or 30k' true vertical depth (TVD), it is instead a deviated well with a long vertical section before the kickoff point which deviates the drillbit to the target at some horizontal displacement from the vertical borehole with the total length of the drillstring being 30k+ feet when they reach TD (total depth). With horizontal drilling and use of steerable mud motors you aren't rotating the drill string constantly as you drill the deviated section and this allows one to push the bit through the formations until you reach the target.

Drilling 6 miles vertically without using a media to conduct cuttings to the surface would be a major change in how things work. I don't think that glassing the inside of the borehole by fusing cuttings as you drill will create a durable borehole. We used to have problems with electronics desoldering at depth in our MWD tools. It gets hot and the pressures can be enormous.

Former Scumbagger MWD engineer here.

How dare you Scumberger! (Me sitting in a scumberger wireline unit rn)

You're completely right doodlebug, our MD is around 30,000 with a TVD of about 26,000' (ballparking here so i'm not violating any contracts).

I also appreciate your other comments here!

They earned any moniker that I apply. Hopefully none of the people that I worked with are still there.

Part 1

I can't edit that other comment any more. I did once because I had a long anecdote trying to give context to the pet name I apply to them. After I reread it I felt like it was too long and meandering.

I worked with them in the mid 90's starting as a JFE running a slimhole MWD that had been developed in Canada by a Canadian company that was bought out by Scumbagger. The tool was never designed to operate at depths and temperatures that are routine in the GoM region and it had numerous issues causing low reliability. Add to that a boom in horizontal drilling using small diameter drillstem for the long reach and there was a busy market for the tool. It was not uncommon to be out for 35 or more days, return to the shop and clean and restock everything, then be called out within 48 hours for another long stint a few miles from Bumfuck or way out on some broken down platform in the GoM out of Fouchon.

The maintenance guys in the shop who were supposed to repair problems, document repairs, and bad tag things that were NFG so they could be repaired had a bit of a lackadaisical attitude about it. It was very common to be deployed with one working MWD, one that failed every roll test and was useless for toolface data, and a pair of gamma tools that may or may not work out of the box. Add to that the chronic absence of spare parts to build and configure tools for the downhole conditions and Scumbagger's insistence that their herd of high-dollar PhDs knew more about the tools and how they should be configured than the FEs who routinely deployed them downhole.

Then throw in clear incentives for FSMs and other managers to screw the FEs out of field bonus they earned. We earned bonuses by keeping our tools in the hole successfully and earning high praise from company men, geologists, etc and were supposed to be paid after each job. FSMs would pore over bit run summaries looking for any excuse to avoid paying the bonuses because all bonus money they failed to pass to FEs went in a pool that was split by managers (who never went into the field.)

It was organized theft by a bunch of FSMs that expected brown-nosing ass-kissers to help them feel good about their character failings and rewarded the brownest noses with fully stocked boxes for their jobs, guaranteed tools that worked, and the cleanest rigs with the best accommodations and working conditions.

Those like myself who refused to kiss ass found themselves stuck out on platforms that wouldn't pass MMS (Minerals Management Service) inspection and would get shut down for the repairs prolonging the duration of a job that was already gonna drag on for weeks longer that it should have due to all the bullshit that everyone on site had to overcome to make it all happen.

I came into the shop after my jobs and cleaned all my tools, identified those that were NFG, checked my required inventory parts list against the supplies I had in the box and put in requests for parts that would be necessary for the next job. Then I filed all my bit run summaries, checked out with my FSM and went home knowing that the bastard was gonna call me if a shit job came up. My box was supposed to ship with me since I was responsible for it. It was normal for me to get called back out, go to the shop to load my gear and my box only to find that one of the brown-nosers had taken my fully stocked box with them "because they didn't have time to get theirs ready". I would be stuck rushing to request parts to fill a box that hadn't been cleaned or inventoried and would regularly find that parts I needed (O-rings, spacers, pulser tool heads) were not in stock even though I could look through the chain link into the parts section and see them in the bins. I resorted to breaking the lock on the parts room and helping myself to everything I needed or simply climbing the chain link in and out.

Other engineers hated that until I passed parts to them that they also needed but had been told were not in stock.

There was so much dysfunction there. It was nothing at all like any other part of the oilfield that I had ever experienced. I had worked pipelining, as a roustabout, as a floor hand, a water hauler, on seismic crews, etc and had never run into so many people all in it for themselves with no regard for the truth. It was expected that we would lie to clients about the tool reliability so that they wouldn't kick us off the location.

I had a meeting with Anadrill's VP and their Global Personnel director and brought up the fact that it seemed to be routine to expect FEs to lie to clients and the VP responded in a carefully worded response that our clients understand that may not get the highest service quality level as advertised but that in exchange, they can get the service for a discount.

One time I answered a client's question about one of the tool's advertised characteristics that made it popular with bean counters. He phrased the question in a way that asked for my own personal experience as it related to that tool performance and so I answered honestly based on events from the job that I had just completed where the tool definitely failed to deliver as advertised.

That honesty caused the company man to kick us off the location in favor of his preferred MWD provider, Halliburton. Pretty funny stuff until I got called into the inquisition about a week later.

To Be Continued in another reply...

Oh I don't work for them, just with them. I'm an independent contractor now after 5 years with exxonmobil. Cut my career short there for the exact same reasons. Talk about organizational dysfunction!!

I totally get that too. Right after I struck out as an independent contractor a long time ago, I did some stuff for ExxonMobil. Very smart people there. Very tight, collaborative structure. It was easy to see how they had been so successful for so long. Lots of things working in sync. Totally unlike the situation at Scumbagger where you advanced quickly if you could get your snout far enough up the FSM's ass. If you were like me and came from an oilfield culture where ass-kissing could get your ass whooped before they fired you (seismic field crews never put up with any bullshit), then it didn't work for me at all. My FSM actively held me back and denied promotions that I had earned, moving the goalposts every time I hit the expected target. I wasn't the only one. He openly bragged that his payroll burden was the lowest in Anadrill for all regions globally because he had the least number of SFEs on his payroll. He said that he delayed promotions at all levels to keep his numbers low. He had come out of college with an MBA on a fast-track to management.

Life is full of new experiences. Every day finds you at another node on the decision tree that will ultimately define and document your life to others. Pick the wrong path and your options at the next node will be less attractive than those behind you. Pick the right path and you can continue like branches on a hackberry, making the most of every opportunity to continue growing toward the light.

Had I followed the path that vengeful rage had offered me I would never have had the opportunities to polish my skills and grow my career into a successful consultancy. They got off easy because I chose to take the long view for my family's sake and chose to let it slide while taking every opportunity to find another job. If I had let it be personal then a lot of things would be different.

Part 2

Continued comment...

I found myself in a room with my FSM, the DM (District Manager), a transcriptionist, and a company lawyer. They quizzed me about the circumstances behind losing that job for them and I answered everything just as it had occurred. It was apparent that the FSM and DM wanted to find a reason to shit-can me for costing them the job but when all the talking was done and they looked over at the lawyer, who had asked his own questions to clarify how it happened, he erased their shit-eating grins when he told them that they did not have grounds to terminate because the client had specifically asked for my own personal perspective based on my own experience with the tool and that I had answered truthfully based not only on my own testimony but on their affirmations confirming that everything I told the client was true and did happen as described. He got up, shook my hand and thanked me for being honest and gave me his card as he told me that I could call him any time if I needed.

The FSM and DM were dumbfounded and both tried to act friendly as if they had only wanted to clear up the circumstances, but I knew that their sudden kindness was a lie and I knew that I needed to actively find something else to do with the rest of my life.

As fate would have it one of the many resumes that I had sent a couple months earlier while recuperating from some surgery was answered by a VP for one of the local geophysical companies there in Houston. He wanted to know whether I was still interested and whether I could drop in for an interview. I had explained in all the cover letters that I was on a deployment yo-yo where I might be on location for more than a month, then in town for less than 2 days before being deployed again and that I would need some flexibility if they were interested in talking with me. The man had left his number so that I could call him directly as soon as I was able. I made that call and was able to meet the guy for several hours that same day. I didn't expect to ever hear back from him but the gods were smiling and a couple days later, on a Friday, I received an offer letter in the mail with instructions to call and talk to him so that he could make sure it was acceptable to me.

I called and accepted his offer to start the next Monday. That whole weekend was such a huge relief. I spent it with my wife doing all the things that we had not had time to do and ignoring all the messages and calls from the FSM wondering where I was, why I wasn't answering the phone, threatening to send someone over to bring me to the shop, etc.

I went to my new job Monday morning and worked all day. The feeling that the weight of the world had been lifted from my shoulders was real, palpable. It was driven home to me when I had spent the whole day taking notes about the OS they were using, the processing software they were using, people's names, etc and was pretty deep into trying to be productive with software I had no experience using and performing a task that I had no experience with and suddenly the room started to empty. My new coworkers were grabbing coats, lunchboxes, etc and heading for the door. I didn't understand it until my new boss came by on his way out the door and asked why I was still there. He told me that it was after 5 and time to go. Just log off and pick it back up tomorrow.

That's when it hit. I didn't have to stay all night dead-tired and working another 40 hour tour with a second hand who was also dead-tired - both of us fixing shit that shouldn't be broken.

I could show up at 8 am, eat lunch at noon, leave at 5 and that was not only normal, it was expected. My evenings were mine - to enjoy. Total culture shock.

Anyone who has ever worked with me after Scumbagger has heard that anecdote. I pass it to you, cnote337, in the hopes that you are having more fun than I did.

As a bonus, my FSM called late that evening screaming about me needing to get down there now or I would be fired. When he realized I was on the phone this time and he wasn't talking to my machine he asked me how long it would take for me to get down there. He needed me yesterday on a GoM job and would be choppering me out to the rig ASAP. As he tried to fill in all the details, I laughed and told him that I had a new job and wouldn't ever be shipping out anywhere. There was a pause and he stuttered a bit, obviously flustered and blurted out something about giving notice and that I couldn't do that without telling him. How was he gonna get someone for that rig...

I just told him that when he noticed I was gone, he'd had all the notice he was gonna get.

We do use conventional drilling for geothermal!

We just have to be more selective with the location to ensure that there is heat nearer the surface. They're right, if you drill deep enough, it's hot everywhere. Even in non-geothermal oil and gas wells, we commonly have temperatures that exceed 250 degrees Fahrenheit. Our tools that we send down whole are commonly rated for 300-350 degree temperatures. Plenty of temperature down there!

Although I admit, I'm an oil and gas guy and don't really have any industry knowledge of geothermal.

Thank you for the detailed answer. I figured there was something wrong with the idea but didn’t know enough about the subject to understand why.

Drilling is essentially an O(N^2) method. You need to replace your drill bit every X meters, and the time it takes to replace it about linear in the current depth.

Note that diamond (usually called PDC) drill bits have been in common use in the oilfield industry for decades now. Search PDC on your favorite search engine, and you'll find dozens of manufacturers actively selling them, each with a big selection.

Exactly how long you can drill with one varies widely based on a bunch of factors. You do have to pull the whole drill string to change one. It's slow, but not that slow. Most actual oil wells drilled have in the neighborhood of 10 or so trips in and out with drilling tools for the whole operation for various reasons. Varies widely of course depending on a bunch of factors, but that's usually the ballpark. Plus a few more for casing and cementing runs.