Who knows?

I don't have a clue why, but just a short time ago, I was lying in my hot
bath contemplating time spent on drilling rigs. I've come to realize that
I've forgotten more than most young guys know. But I digress.
Question: Why is it that 5" drill pipe comes in random lengths. Every
crane operator had that denim covered tally book in their back pocket, and
losing it could bring on severe consequences.
Out of everything we used, jars, collars, stabilizers, saver subs, fishing
tools, ........... the thing there was the most of was drilling pipe, and
that would seem to be the easiest to fabricate in standard lengths. Same
with casing.
Can anyone tell me?
Steve
Reply to
SteveB
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========== My guess is that the drill pipe comes from the factory more or less standard length, but as time goes on, the threads on one end or the other get dorked, and these are recut. Several dinged threads = short joint.
Unka' George [George McDuffee] ------------------------------------------- He that will not apply new remedies, must expect new evils: for Time is the greatest innovator: and if Time, of course, alter things to the worse, and wisdom and counsel shall not alter them to the better, what shall be the end?
Francis Bacon (1561-1626), English philosopher, essayist, statesman. Essays, "Of Innovations" (1597-1625).
Reply to
F. George McDuffee
It's always getting cut off and the ends remachined?
(I know nothing of oil drilling)
Reply to
Tim Wescott
I can't tell you for sure, because I've never worked where you have, but I can make a guess.
Don't the threads on on the couplings on the ends of the pipes get banged up and have to be cut off and a new one welded in place? The more times this happens, the shorter the pipe? Certainly the pipes are expensive enough to be worth repairing if possible.
Enjoy, DoN.
Reply to
DoN. Nichols
I borrowed a tank skid the other day and had to wait for a truck to be loaded and I listened to them tally pipe and 95% of the pipe was 31.50 ft I asked where did it come from? China they said. It was tubing and not drill pipe.
What part of Texas are you from??
Scott
Reply to
jano
Pins and collars are standard sizes, but stem tends to be random lengths from the mill. Plus pipe repairs, recutting the pins, cutting off collars and replacing them etc etc tend to make pipe lengths rather random.
Some drill stem I punched in the ground was over 50 yrs old, based on company records.
But its a really good question.
Gunner
"Lenin called them "useful idiots," those people living in liberal democracies who by giving moral and material support to a totalitarian ideology in effect were braiding the rope that would hang them. Why people who enjoyed freedom and prosperity worked passionately to destroy both is a fascinating question, one still with us today. Now the useful idiots can be found in the chorus of appeasement, reflexive anti-Americanism, and sentimental idealism trying to inhibit the necessary responses to another freedom-hating ideology, radical Islam"
Bruce C. Thornton, a professor of Classics at American University of Cal State Fresno
Reply to
Gunner Asch
I=92m no expert, but my guess is that random lengths might lessen resonance problems (or vibration harmonics) that could damage the drill string. I can=92t prove this. I can show that vibration (torsional, axial, lateral) is a concern:
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Reply to
guillemd
I think that is a good guess. Just up the road is a shop with a big lathe, the steady is out side with a pipe rack. They make their living cutting the unique threads used in the industry.
I don't know much more about the drilling side of things though I was once a night watchman on a work over rig.
Wes
Reply to
Wes
I don't know about new pipe but I worked, for a short time, at a place in Shrevesport that repaired pipe by cutting the tool joints off and welding on new joints.
Cheers,
Bruce in Bangkok (bruceinbangkokatgmaildotcom)
Reply to
Bruce in Bangkok
Nah. If you look at a piece, the shaft is smaller diameter than the ends. Screwing up an end would make it unserviceable, since the ends are bigger. Unless, they weld on another end assembly. But I don't think so.
Steve
Reply to
SteveB
Take a look at this. It will explain the shape, and why they wouldn't be remachined on the ends.
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Steve
Reply to
SteveB
Utah. I worked in the oilfield boom of the 70's in the Gulf of Mexico, and later in the nineties. Made some trips overseas, too. Diver, welder, crane operator.
Steve
Reply to
SteveB
Then I guess they CAN be repaired. Length varied by up to three feet.
Steve
Reply to
SteveB
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It never ceases to amaze me that people come up answers with out knowing anything about the subject under discussion. ...lew...
Reply to
Lew Hartswick
_Guesses_ -- at least in my case.
I usually wait a bit before answering (or guessing), and keep my fingers off the keyboard if someone who actually knows what they're talking about comes on.
Reply to
Tim Wescott
Actually...most are buttress thread and can be remachined a bit.
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"Lenin called them "useful idiots," those people living in liberal democracies who by giving moral and material support to a totalitarian ideology in effect were braiding the rope that would hang them. Why people who enjoyed freedom and prosperity worked passionately to destroy both is a fascinating question, one still with us today. Now the useful idiots can be found in the chorus of appeasement, reflexive anti-Americanism, and sentimental idealism trying to inhibit the necessary responses to another freedom-hating ideology, radical Islam"
Bruce C. Thornton, a professor of Classics at American University of Cal State Fresno
Reply to
Gunner Asch
I am really surprised no one has better knowledge on this issue.
I, too, know nothing about a new string, though most drill stem I've seen has been quite uniform. The cost of a new string of pipe must be phenomenal, as it was cost effective to try to get one more hole out of a string. Of course, if the gamble failed you owned a bunch of tonnage of steel down a mighty skinny hole.
Baker tooling used to have a plant here. I did outside contractor work for their site. Their specialty was to sandblast the inside of drill stem, spray apply a coat of epoxy, send through some ovens, apply second epoxy coat, then fill a special train car that would hold one company's set of drill stem to bake in an enclosed oven for over a day. They had another machine outside that would slowly turn a drill stem as a machine powder welded a new surface on the drill collars (I'm sure there's a fancier name for the process). Fascinating machinery, and you should have seen the forklifts that could handle a full load of drill stem.
Reply to
DanG
Well then apparently you are not as smart as you think you are.
No matter how carefully you measure a slug or billet in preparation for forming a pipe, you cannot accurately predict the finished length unless you can assure you maintain the exact ID, OD and will thickness over the entire length. Check tolerances on any tube or pipe and you will quickly see enough variation to seriously affect it's finished length. That's why they are sold in random lengths. Cutting them to exact lengths would always increase the scrap or return rate, and increase the cost per foot.
Now if you are just sticking one pipe in the ground after the other, why waste 6-18" per joint just to make them all the same length? If you accept random, you will get a free joint about every 20 to 30 joints. So it' much more cost effective to measure and count.
Reply to
Elliot G
Hard banding
Gunner
"Lenin called them "useful idiots," those people living in liberal democracies who by giving moral and material support to a totalitarian ideology in effect were braiding the rope that would hang them. Why people who enjoyed freedom and prosperity worked passionately to destroy both is a fascinating question, one still with us today. Now the useful idiots can be found in the chorus of appeasement, reflexive anti-Americanism, and sentimental idealism trying to inhibit the necessary responses to another freedom-hating ideology, radical Islam"
Bruce C. Thornton, a professor of Classics at American University of Cal State Fresno
Reply to
Gunner Asch
"Tim Wescott" wrote
I can tell you what a chickshin line is, what a BOP is, how a Hydril works, what a Christmas Tree is, what bentonite does, what a collar is, what a cathead is, but I just don't know why they wouldn't make drill pipe 40' apiece instead of all around that figure. Maybe someone will know.
Steve
Reply to
SteveB

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