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Engineering Tools · U-Bolt Reference

DN50 U-Bolt Dimensions Chart (for 60.3 mm Pipe)

DN50 U-Bolt Dimensions (unit mm)

Form: round bar bent into a U with threads cut or rolled on both leg ends, closed by nuts and washers to clamp pipe or section. Round bend (semicircular) and square bend (right-angle) are distinct forms agreed by drawing; this chart covers the round bend basis.

Matching pipe OD (nominal DN)60.3 mm (DN50)
Inside width A (mm)76 mm
Leg length (mm)49 mm
Overall height H (mm)109 mm
Matching thread size Catalog pairingM10 (pitch P=1.5 mm)
Thread length (per leg)50 mm
Rod diameters availableM10 / M12 / M16
Bend centreline length (mm)135.1 mm
Developed length (mm)233.1 mm

Thread pairing source tags: "Catalog pairing" means the value was extracted size by size from the spec_json of U-bolt SKUs in the product catalog (same source as the product pages; the extraction script ops/tools/gen-ubolt-dims.py can be re-run to verify). "Assumed" would mean the catalog has no SKU covering that pipe-OD band and a conventional pairing was assumed and flagged here. All 11 bands in this chart are catalog pairings; none is assumed.

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Other Sizes

Pipe OD Reverse Lookup: Which U-Bolt Fits (all 11 sizes)

Sizing entry point: measure the actual pipe outside diameter, find that band in the left column, and the same row gives the inside width, leg length, overall height and matching thread for that pipe size; click the DN number to open that size. Pipe ODs follow the GB/T 1047 metric series. If the measured OD falls between two bands, or the pipe is inch (NPS), size to the next band up and confirm with the supplier.

Pipe OD (mm)Nominal DNInside width A (mm)Leg length (mm)Overall height H (mm)Matching threadRod diameters available
21.3DN15332360M6M6
26.9DN20402870M6M6 / M8
33.7DN25483176M6M6 / M8 / M10
42.4DN32563786M8M8 / M10
48.3DN40624092M8M8 / M10 / M12
60.3DN507649109M10M10 / M12 / M16
76.1DN659457125M10M10 / M12 / M16
88.9DN8010666138M12M12 / M16 / M20
114.3DN10013678171M12M12 / M16 / M20
139.7DN12516484191M16M16 / M20
168.3DN15019296217M20M20

"Rod diameters available" lists every round bar diameter the catalog offers for that pipe-OD band; the default pairing is the lightest of them (tagged on each size page), and one step up suits heavy or vibrating duty. Bend type, thread length and the number of matching nuts and washers are confirmed by drawing or at inquiry.

DN50 Unit Weight by Configuration (per available rod diameter)

A U-bolt's unit weight moves with rod diameter and developed length together: developed length = 2 x leg length + bend centreline length (a semicircle of radius (inside width + rod diameter)/2), so the bend grows with the rod too and each step up in diameter adds weight faster than the square of the diameter alone.

Rod diameterBend centreline length (mm)Developed length (mm)Unit weight (g/pc)Bulk (kg/1,000 pcs)
M10Default pairing135.1233.1144144
M12138.2236.2210210
M16144.5242.5383383

Unit weight = developed length x pi/4 x d^2 x 7.85 g/cm3 for carbon steel, rounded to avoid false precision (display-layer tiered decimals: at least 2 decimals below 1 kg, 1 decimal from 1 to 10 kg, whole kg at 10 kg and above). Matching nuts and washers are counted separately; see the related charts at the foot of the page.

Material Density Conversion

Table values are for carbon steel (7.85 g/cm3); other materials convert by density ratio: weight x factor (geometry unchanged).

MaterialDensity (g/cm3)Conversion Factor
Carbon Steel7.85×1.000
304 Stainless Steel7.93×1.010
316 Stainless Steel7.98×1.017
Brass8.5×1.083

Calculation Basis and Assumptions Disclosed

Calculation basis

  • Dimensions come from fastenerCalc: inside width, leg length and overall height are mapped from UB_PIPES (DIN 3570 series geometry, same source as the product catalog SKUs); the matching thread size comes from UB_THREAD (extracted size by size from the live prd_sku.spec_json, see the source tag in the table above); pitches follow the GB/T 196 metric coarse table.
  • Unit weights are computed from geometry: developed length = 2 × leg length + bend centreline length, the bend taken as a semicircle on the centreline (radius = (inside width + rod diameter)/2), rod at nominal full diameter, 7.85 g/cm³ for carbon steel, base metal only, coating excluded — the same developed-length basis as the catalog spec_json developedLengthMm, reconciled row by row.
  • The main values are computed at nominal full diameter, the same basis as the catalog unit_weight_g; the threaded portions of both legs are roll formed and lose a little material — applying the 0.97 rolled-thread allowance puts this size at roughly 139.4 g/pc (about 3% lower). Either basis can be used for batch costing; the main table stays unadjusted so it matches the catalog.

Scope & limits

  • Unit weights are theoretical geometry estimates for quotation, freight and packing budgets; trade settlement is against actual measurement.
  • Actual weight varies with bend radius, thread accuracy and coating (hot-dip galvanizing ≈ +4.5%).
  • Inside width, leg length and overall height are catalog-modelled dimensions; square bends, extended legs, inch pipe (NPS) and special thread forms are made to drawing, and this chart is not an acceptance basis.
  • Theoretical estimate tolerance ±5%.

Cite this chart

YAXIIO. DN50 U-Bolt Dimensions Chart (for 60.3 mm Pipe). https://www.yaxiio.com/en/tools/u-bolt-chart/dn50 (accessed 2026-10-29).

Free to cite and embed — attribution required: “YAXIIO” + a link to this page.

FAQ

How do I pick a U-bolt by pipe outside diameter?

Measure the actual pipe OD first, then use the reverse lookup table on this page: an OD of 60.3 mm maps to DN50, and that row gives inside width 76 mm, leg length 49 mm, overall height 109 mm and matching thread M10. When the measured OD falls between two bands, take the next band up so the inside width still clears the pipe; for inch pipe (NPS), match the metric band of the same nominal bore and confirm with the supplier.

How are the bend, developed length and overall height of a U-bolt measured?

Inside width A is the clear distance between the inner faces of the legs (76 mm for DN50); leg length is the straight run from the end of the bend to the thread end (49 mm); overall height H is the total height from the outside of the bend to the leg ends (109 mm); the bend centreline length is taken as a semicircle of radius (inside width + rod diameter)/2, which is 135.1 mm for DN50; developed length = 2 x leg length + bend = 233.1 mm. A different measurement convention changes the quoted figure, so agree it with the supplier before ordering.

Related References

Disclaimer: This table is engineering estimate data for selection, quotation and freight estimation reference only, not a design basis or acceptance standard.