{
 "version": "2026-10-20",
 "license": "Dimension sheets: CC BY 4.0. Standard and published-size files: CC BY 4.0. Xem Studio's own designs (files_license = Xem Studio Design License): free to use and sell things from, not to redistribute as files — https://xemstudio.com/license/. Other publishers' files: their own license, linked beside them.",
 "slug": "u-bolts-by-pipe-size",
 "name": "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",
 "kind": "standard",
 "category": "Hardware",
 "group": "Fasteners",
 "year": null,
 "question": "What size U-bolt do I need for a 2 in pipe, and what thread and inside width does it have?",
 "tags": [
  "u-bolt",
  "u bolt",
  "pipe clamp bolt",
  "muffler clamp",
  "pipe support",
  "square tube u-bolt",
  "fastener",
  "rod size",
  "tool"
 ],
 "aliases": [
  "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"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "not-scanned",
 "les": false,
 "free_files": 0,
 "url": "https://xemstudio.com/objects/u-bolts-by-pipe-size/",
 "sheet_txt": "https://xemstudio.com/objects/u-bolts-by-pipe-size/sheet.txt",
 "sheet": {
  "basis": "Albany County Fasteners' U-bolt size chart (round pipe and square tubing), with one Zoro listing as a cross-check; numbers only",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "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."
  ],
  "table": {
   "columns": [
    "support",
    "nominal size",
    "pipe OD",
    "U-bolt inside dia",
    "thread",
    "inside width",
    "thread length"
   ],
   "rows": [
    [
     "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\""
    ]
   ]
  }
 },
 "sheet_text": "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 — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/u-bolts-by-pipe-size/  (sheet CC BY 4.0)\nBasis: Albany County Fasteners' U-bolt size chart (round pipe and square tubing), with one Zoro listing as a cross-check; numbers only\nCatalog version: 2026-10-20\n\nSizes: see table below\n- 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.\n- 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.\n- 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.\n- 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.\n\nsupport  nominal size  pipe OD  U-bolt inside dia  thread  inside width  thread length\nround pipe (NPS)  1/2\"  0.840\"  7/8\" to 1\"  3/8\"-16  1-1/4\" to 2\"  2\" to 3\"\nround pipe (NPS)  3/4\"  1.050\"  1-1/8\" to 1-1/4\"  3/8\"-16  1-1/2\" to 2\"  2\" to 3\"\nround 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\"\nround 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\"\nround pipe (NPS)  1-1/2\"  1.900\"  2\"  1/2\"-13  2-1/4\" to 3\"  3\" to 4\"\nround pipe (NPS)  2\"  2.375\"  2-1/2\"  1/2\"-13  2-1/2\" to 3-1/2\"  3\" to 4\"\nround pipe (NPS)  2-1/2\"  2.875\"  3\"  5/8\"-11  3\" to 4\"  3-1/2\" to 5\"\nround pipe (NPS)  3\"  3.500\"  3-1/2\" to 4\"  5/8\"-11  3-1/2\" to 5\"  4\" to 6\"\nround pipe (NPS)  4\"  4.500\"  4-1/2\" to 5\"  3/4\"-10  4\" to 6\"  4\" to 6\"\nround pipe (NPS)  5\"  5.563\"  5-1/2\" to 6\"  3/4\"-10  5\" to 7\"  5\" to 7\"\nround pipe (NPS)  6\"  6.625\"  6-1/2\" to 7\"  7/8\"-9  6\" to 8\"  6\" to 8\"\nsquare tubing  1\" × 1\"  —  1\" × 1\"  3/8\"-16  2\" to 2-1/2\"  2-1/2\" to 3\"\nsquare 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\"\nsquare 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\"\nsquare tubing  2\" × 2\"  —  2\" × 2\"  1/2\"-13  3\" to 4\"  3\" to 4\"\nsquare tubing  2-1/2\" × 2-1/2\"  —  2-1/2\" × 2-1/2\"  5/8\"-11  3-1/2\" to 5\"  4\" to 5\"\nsquare tubing  3\" × 3\"  —  3\" × 3\"  5/8\"-11  4\" to 6\"  4\" to 6\"\nZoro listing (cross-check, 'pipe size' 3/8 in)  3/8\"  —  —  1/4\"-20  3/4\" (inside height 2-1/4\")  1-1/2\"\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- 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 — https://www.albanycountyfasteners.com/media/55/34/ee/1764619822/u-bolt-size-chart.pdf\n- 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 — https://www.zoro.com/zoro-select-14-20-x-38-pipe-size-black-oxide-u-bolt-10-pk-u172420250038/i/G9010836/\n\nNo true-size file yet: the published figures do not fix the whole shape; a measured scan is planned.\nAPI: https://xemstudio.com/api/geometry?object=u-bolts-by-pipe-size\n",
 "sources": [
  {
   "publisher": "Albany County Fasteners",
   "title": "U-bolt size chart: round pipe and square tubing, U-bolt inside diameter, thread size, inside width range, thread length range",
   "url": "https://www.albanycountyfasteners.com/media/55/34/ee/1764619822/u-bolt-size-chart.pdf",
   "formats": [
    "web"
   ],
   "license": "Distributor chart; numbers only",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Zoro (Zoro Select listing)",
   "title": "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",
   "url": "https://www.zoro.com/zoro-select-14-20-x-38-pipe-size-black-oxide-u-bolt-10-pk-u172420250038/i/G9010836/",
   "formats": [
    "web"
   ],
   "license": "Retail listing; numbers only",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "not-scanned",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "wire-rope-clips-crosby-g450-g429",
  "hex-nuts-inch",
  "flat-washers-inch",
  "threaded-rods-metric",
  "strut-channel-1-5-8",
  "emt-conduit",
  "steel-pipe-asme-b36-10m-nps-1-8-to-24"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no tolerance added)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no tolerance added. Where a part meets another part, the object lists its mating features (feature, exact size, what it mates with, fit class: press, slide, run, socket, clamp or designed). Apply your process's allowance to those features only; 'designed' gaps are part of the design and stay as drawn. Typical accuracy by process and ISO 286 fits: https://xemstudio.com/tolerances/",
 "mating": [
  {
   "feature": "inside diameter",
   "exact": "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)",
   "mates": "steel pipe of the nominal size (round pipe rows) or tube of the listed section (square rows)",
   "fit": "clamp",
   "files": "all"
  },
  {
   "feature": "thread",
   "exact": "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)",
   "mates": "UNC nut and washer / backing plate of the same thread (hex-nuts-inch, flat-washers-inch)",
   "fit": "designed",
   "files": "all"
  }
 ],
 "fit_classes": {
  "press": "stays put: pin, tube, bearing or magnet held by interference. ISO 286 equivalent: H7/p6 (locational interference) or tighter.",
  "slide": "assembles by hand and is held by a grub, pinch or clamp: shaft in a hub, rod in a socket, spigot in a bore. ISO 286 equivalent: H7/g6 or H7/h6.",
  "run": "turns or slides in use: pin in a link, rod through a guide. ISO 286 equivalent: H8/f7 (close running).",
  "socket": "large sliding fit: syringe barrel, sleeve, bobbin in a bore. ISO 286 equivalent: H9/d9 (free running) or looser.",
  "clamp": "split part that closes on the mating part with screws: make it at size.",
  "designed": "a gap that is part of the design (piston fit option, displacer gap, air gap): do not change."
 },
 "faq": [
  {
   "q": "What U-bolt fits 2 in pipe?",
   "a": "Albany County Fasteners' chart: inside diameter 2-1/2 in, thread 1/2-13, inside width 2-1/2 to 3-1/2 in, thread length 3 to 4 in (pipe OD 2.375 in)."
  },
  {
   "q": "What thread does a U-bolt for 4 in pipe use?",
   "a": "3/4-10 on the chart, inside diameter 4-1/2 to 5 in, inside width 4 to 6 in, thread length 4 to 6 in."
  },
  {
   "q": "What is the inside width of a U-bolt?",
   "a": "The leg spacing: the chart prints ranges, for example 1-3/4 to 2-1/2 in for 1 in pipe and 3-1/2 to 5 in for 3 in pipe."
  }
 ],
 "files_license": null,
 "offers": [],
 "markdown": "https://xemstudio.com/objects/u-bolts-by-pipe-size/index.md"
}