I am installing some equipment that requires torquing some flare fittings to different measurements (18 ft lbs, 23 ft lbs, etc). Trouble is, all the torque wrenches I see are for use with sockets, and sockets won’t work with a pipe fitting. Any idea where I can find the appropriate type of wrench (one that won’t bankrupt me, hopefully, since I’m unlikely to need it again, or at least often)? Adjustable would be better, because there are several different size fittings.
How about using a crow’s foot extension on your torque wrench?
Yep, crows feet are what you want. Not commonly found at Sears, though a good tool catalog should have them.
won’t that change the reading, since it’s effectively lengthening the wrench?
http://www.cditorque.com/pdfs/CDITorqueFacts2005.pdf
See page 4 for how to calculate the correct torque.
Probably the only feasible way is with a crowsfoot, and since they’re fittings, it really should be a flare nut crowsfoot. Standard open-end (parallel jaws) crowsfoot wrenches tend to slip and round off the corners of flare nuts. Crowsfoots are made in individual sizes - it’s probably impossible to make an adjustable one, and I’ve never seen one.
A crowsfoot sticking out past the torque wrench’s drive center will increase its working length and affect the reading. If you know the wrench’s working length (usually not its overall length), it’s a pretty straightforward calculation to compare the “old” and “new” working lengths and adjust the reading to correct for this. Alternatively, sometimes you can have the crowsfoot sticking out at 90 degrees to the wrench’s handle, and then the change in working length is quite minor.
Another possibility is that the fittings don’t actually require torquing. I deal with flare nut fittings on brake and fuel lines, but I don’t tighten them with a torque wrench. I use my “calibrated wrist” (feel developed through experience) and have had no problems. I wouldn’t try that on a cylinder head bolt or crankshaft bearing nut, but the fittings I deal with don’t demand that degree of tightening precision.
Depending on the size and torque value required, you may need a flare nut crows foot wrench.
These are really uncommon, but they will prevent you from rounding off the corners of the flare nut.
Crows foot flare nut wrenches
Regular crows foot
Meant to add, even if you decide not to torque them, it’s still best to use a flare nut wrench, not an open-end wrench.
You find out what its grammatical pet peeve is, like splitting infinitives or using “myself” where “me” is appropriate, and then you make it a point to violate it several times whenever you meet. And make sure it knows you’re aware of what you’re doing.
Initially, it will be merely annoyed. But with enough time and repitition, it will be seriously “torqued.”
Flare-nut crowsfoot wrenches are available from Snap-on tools. They’re top quality, but the pricing leans towards the “bankrupt you” side.