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U-bolts by pipe size: thread, inside diameter, inside width and thread length for 1/2 to 6 in pipe and 1 to 3 in square tube

What size U-bolt do I need for a 2 in pipe, and what thread and inside width does it have? · Standard part · basis: Albany County Fasteners' U-bolt size chart (round pipe and square tubing), with one Zoro listing as a cross-check; numbers only

Also called: u bolt size for 2 inch pipe, u-bolt dimensions chart, u bolt thread size pipe, u bolt inside width, 1 inch pipe u-bolt size, u bolt for 1-1/2 pipe, u-bolt thread length, u bolt for 2x2 square tube, u-bolt sizing chart pipe, 3/8-16 u-bolt pipe size, round u bolt dimensions, square u-bolt size

Exact dimensions. Every file is drawn at true size with no tolerance added. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your process's clearance before making the part. Mating features

sizes: 18 in table

Notes

Rows are the distributor's chart, inches: for each nominal pipe size the pipe outside diameter, the U-bolt inside diameter, the thread size, the inside width (leg spacing) as a range and the thread length as a range. Ranges are the available sizes the chart prints, not tolerances. The chart prints two thread sizes for 1-1/4 in pipe (3/8-16 or 1/2-13). Square tubing rows give the U-bolt's inside dimension, thread, inside width and thread length. The chart has no overall height / length column, so none is given here; U-bolts are also made to order in other lengths.
Cross-check: a Zoro Select U-bolt for 3/8 in pipe prints thread 1/4-20, inside width 3/4 in, inside height 2-1/4 in, thread length 1-1/2 in. That size is not in the Albany chart (which starts at 1/2 in pipe and 3/8-16). The Albany chart's 1/2 and 3/4 in pipe rows use a 3/8-16 thread; other makers, for example the Anvil Fig. 137 listing at 3/4 in pipe with a 1/4 in thread (title only, no table read), use lighter rods, so the thread depends on the maker and load.
The chart's own notes (not Xem's): use a backing plate or saddle to spread clamping force and avoid distorting the pipe; measure the outside diameter including insulation on insulated pipe; thread engagement in the nut at least 1.5 × bolt diameter; inside width should accommodate the backing plate plus 1/4 to 1/2 in of clearance. Torque figures on the chart were not read and are not given.
Not on this page: bend radius, overall length, ASME / ISO U-bolt standards (none was read) and load ratings. No file: the U-bolt bend and thread are not given as a complete set of numbers by the sources read, so a drawing would be invented. Pipe OD itself: asme-b16-5-flange-bolt-patterns and emt-conduit; wire rope U-bolt clips: wire-rope-clips-crosby-g450-g429. McMaster-Carr sells U-bolts with per-part STEP; its category is linked, not copied.

U-bolts by pipe size: thread, inside diameter, inside width and… size chart

support	nominal size	pipe OD	U-bolt inside dia	thread	inside width	thread length
round pipe (NPS)	1/2"	0.840"	7/8" to 1"	3/8"-16	1-1/4" to 2"	2" to 3"
round pipe (NPS)	3/4"	1.050"	1-1/8" to 1-1/4"	3/8"-16	1-1/2" to 2"	2" to 3"
round pipe (NPS)	1"	1.315"	1-3/8" to 1-1/2"	3/8"-16	1-3/4" to 2-1/2"	2-1/2" to 3-1/2"
round pipe (NPS)	1-1/4"	1.660"	1-3/4"	3/8"-16 or 1/2"-13	2" to 3"	2-1/2" to 3-1/2"
round pipe (NPS)	1-1/2"	1.900"	2"	1/2"-13	2-1/4" to 3"	3" to 4"
round pipe (NPS)	2"	2.375"	2-1/2"	1/2"-13	2-1/2" to 3-1/2"	3" to 4"
round pipe (NPS)	2-1/2"	2.875"	3"	5/8"-11	3" to 4"	3-1/2" to 5"
round pipe (NPS)	3"	3.500"	3-1/2" to 4"	5/8"-11	3-1/2" to 5"	4" to 6"
round pipe (NPS)	4"	4.500"	4-1/2" to 5"	3/4"-10	4" to 6"	4" to 6"
round pipe (NPS)	5"	5.563"	5-1/2" to 6"	3/4"-10	5" to 7"	5" to 7"
round pipe (NPS)	6"	6.625"	6-1/2" to 7"	7/8"-9	6" to 8"	6" to 8"
square tubing	1" × 1"	—	1" × 1"	3/8"-16	2" to 2-1/2"	2-1/2" to 3"
square tubing	1-1/4" × 1-1/4"	—	1-1/4" × 1-1/4"	3/8"-16	2-1/4" to 3"	2-1/2" to 3-1/2"
square tubing	1-1/2" × 1-1/2"	—	1-1/2" × 1-1/2"	1/2"-13	2-1/2" to 3-1/2"	3" to 4"
square tubing	2" × 2"	—	2" × 2"	1/2"-13	3" to 4"	3" to 4"
square tubing	2-1/2" × 2-1/2"	—	2-1/2" × 2-1/2"	5/8"-11	3-1/2" to 5"	4" to 5"
square tubing	3" × 3"	—	3" × 3"	5/8"-11	4" to 6"	4" to 6"
Zoro listing (cross-check, 'pipe size' 3/8 in)	3/8"	—	—	1/4"-20	3/4" (inside height 2-1/4")	1-1/2"

Mating features

Drawn at the exact size. Open press, slide, run and socket features by your process's clearance (tolerances by process); leave designed gaps and clamp fits as drawn.

feature	exact	mates with	fit	files
inside diameter	2 in pipe (OD 2.375 in): inside dia 2-1/2 in; 4 in pipe (OD 4.500 in): 4-1/2 to 5 in (Albany County Fasteners chart)	steel pipe of the nominal size (round pipe rows) or tube of the listed section (square rows)	clamp	all
thread	3/8-16 (1/2 to 1 in pipe), 1/2-13 (1-1/2 and 2 in), 5/8-11 (2-1/2 and 3 in), 3/4-10 (4 and 5 in), 7/8-9 (6 in)	UNC nut and washer / backing plate of the same thread (hex-nuts-inch, flat-washers-inch)	designed	all

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Albany County Fasteners	U-bolt size chart: round pipe and square tubing, U-bolt inside diameter, thread size, inside width range, thread length range	web	Distributor chart; numbers only
Zoro (Zoro Select listing)	Round U-bolt 1/4-20 for 3/8 in pipe: inside width 3/4 in, inside height 2-1/4 in, thread length 1-1/2 in	web	Retail listing; numbers only

Xem scan

File coming

No downloadable true-size file yet: the published figures do not fix the whole shape, and Xem never guesses a number. A measured scan is planned; request it and it moves up.

Let your AI pull this. Add https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.

Set it up →

Plain text: sheet.txt · JSON: /api/geometry?object=u-bolts-by-pipe-size

Schematic, not to scale.