Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
Monel 400 Anchor Bolts - L-Bolt, J-Bolt, Headed & Swedged, UNS N04400
Monel® 400 anchor bolts (also called Monel 400 L-bolts, Monel 400 J-bolts, UNS N04400 anchor bolts, nickel-copper anchor bolts, or 2.4360 anchor bolts) anchor structural steel, equipment skids, jetty bollards and crane base plates to reinforced concrete in chloride-laden marine, sour gas and hydrofluoric acid service. The mechanical floor is set by ASTM F468 Class A (Ni 400, weldable); the embedded geometry follows the project structural drawing and may reference ASTM F1554 for dimensional convention. Chemistry derives from ASTM B164 bar; the alloy registers as UNS N04400 and DIN 17743 NiCu30Fe (2.4360). Monel is a registered trademark of Special Metals Corporation; TorqBolt is not authorized by, affiliated with or endorsed by Special Metals.
Geometry Types - L, J, Headed and Swedged
Four embedded-end profiles cover the anchorage envelope in nickel-copper. Geometry selection follows the rebar cage layout, slab thickness and required pull-out. Mechanical floor and material certification are identical across all four (F468 Class A).
| Geometry | Embedded shape | Hook / head dimensions | Specify when |
|---|---|---|---|
| L-bolt | 90 degree bend at the embedded end | Hook leg 4 to 6 times shank diameter; bend radius 3 times shank diameter | Shallow embedment, moderate pull-out, clear rebar layout |
| J-bolt | 180 degree return at the embedded end | J return 4 times shank diameter; bend radius 3 times shank diameter | Congested rebar cage where 90 degree leg interferes |
| Headed anchor | Hex or square head forged on the embedded end | Hex head 1.5 times shank across flats; embedment 8 to 12 times shank diameter | Maximum pull-out per inch of embedment; head bears in pure compression |
| Swedged anchor | Rolled deformations along the embedded length | Deformation pitch 1 to 2 times shank diameter; full bond on embedment length | No hook clearance; bond-controlled anchorage; thin slab pours |
Embedment Design and Concrete Pull-Out
Anchor design follows ACI 318 Chapter 17 (anchorage to concrete) and the structural engineer's calculation governs embedment depth. Three failure modes drive the design: concrete cone breakout, steel tensile fracture and pull-out. The F468 Class A floor (70 to 130 ksi tensile) exceeds the cone breakout capacity of typical 4000 to 6000 psi concrete at the embedment depths used in marine and chemical-plant foundations, so concrete strength and edge distance govern the load envelope. Headed anchors with embedment of 8 to 12 times the shank diameter develop near-full F468 yield; L-bolts and J-bolts develop 60 to 80 percent of headed-anchor capacity at the same embedment. Edge distance below 6 times the shank diameter triggers a side-face blowout check per ACI 318 17.6.4.
Size Range - M16 to M64 / 5/8 to 2-1/2 inch
Sizes are produced from ASTM B164 hot-finished bar (condition AR or HF, sulfur 0.024 max for Class A). M48 through M64 and 1-3/4 through 2-1/2 inch indent through ASTM B564 forging stock with mechanicals matched to F468 Heavy Forged Equivalent. Thread cut to ASME B1.1 UNC or ISO 261 metric coarse; projecting thread length is typically 3 to 5 times the shank diameter.
| Metric size | Tensile area (sq.mm) | Imperial size | Tensile area UNC (sq.in) | Typical stocked length |
|---|---|---|---|---|
| M16 | 157 | 5/8 | 0.226 | 200 to 600 mm / 8 to 24 in |
| M20 | 245 | 3/4 | 0.334 | 250 to 750 mm / 10 to 30 in |
| M24 | 353 | 7/8 | 0.462 | 300 to 900 mm / 12 to 36 in |
| M27 | 459 | 1 | 0.606 | 350 to 1050 mm / 12 to 48 in |
| M30 | 561 | 1-1/8 | 0.763 | 400 to 1200 mm / 14 to 48 in |
| M36 | 817 | 1-1/4 | 0.969 | 500 to 1500 mm / 18 to 60 in |
| M42 | 1120 | 1-1/2 | 1.405 | 600 to 1800 mm / 24 to 60 in |
| M48 | 1470 | 1-3/4 | 1.90 | 700 to 2000 mm / indent |
| M56 | 2030 | 2 | 2.50 | 800 to 2200 mm / indent |
| M64 | 2680 | 2-1/2 | 3.25 | 900 to 2500 mm / indent |
F468 Mechanical Floor (Class A, Weldable)
Anchor bolts in Monel 400 are supplied to ASTM F468 Class A (UNS N04400, sulfur 0.024 max, weldable). Class B (UNS N04405, sulfur 0.025 to 0.060) is not recommended for embedded service because the higher sulfur compromises field welds to the rebar cage and reduces toughness. The verified F468 Class A floor (source: ASTM F468/F468M-2016 Table 2) is reproduced below.
| F468 marking | Diameter (in) | Hardness | Tensile (ksi) | Tensile (MPa) | Yield min (ksi) | Yield min (MPa) | Elongation |
|---|---|---|---|---|---|---|---|
| F 468U | 0.250 to 0.750 | 75 HRB to 25 HRC | 80 to 130 | 552 to 896 | 40 | 276 | 20% |
| F 468U | 0.875 to 1.500 | 60 HRB to 25 HRC | 70 to 130 | 483 to 896 | 30 | 207 | 20% |
| F 468U4 | 0.875 to 1.500 | 75 HRB to 25 HRC | 80 to 130 | 552 to 896 | 40 | 276 | 20% |
| F 468HF | all (heavy forged equivalent) | 60 to 95 HRB | 70 to 120 | 483 to 827 | 30 | 207 | 20% |
F468 caps hardness at 25 HRC across the embedded service range, well inside the 35 HRC ceiling set by NACE MR0175 for nickel-copper bolting in H2S service. Anchor bolts therefore clear the sour-service hardness gate by design. Each lot ships with EN 10204 type 3.2 mill test certificate covering chemistry, mechanicals, hardness, and dimensional inspection.
Companion Nuts, Washers and Leveling Hardware
Anchor bolts ship as a kit: bolt + two nuts + two washers + leveling sleeve when specified. Nut chemistry matches the bolt to prevent galvanic discontinuity at the flange interface.
- Heavy hex nuts to ASTM F467 Class A (heavy hex pattern) - one above the base plate, one below as a leveling nut.
- Plain washers to ASME B18.22.1 (Monel 400 washer, DIN 125 dimension) for preload distribution.
- Fender washers (DIN 9021, outside diameter 3 times shank) for oversized base-plate holes.
- Lock nuts to F467 (prevailing torque or DIN 985 nylon insert) on rotating equipment skids.
- Leveling sleeves in F468 threaded rod or B164 round bar for grout-pocket installations.
Applications - Marine, HF Alkylation, Naval Foundations
Marine jetty bollards and dolphin foundations: Splash-zone exposure to chloride seawater pits austenitic stainless (316L) and crevice-attacks duplex grades at the concrete interface. Monel 400 anchors resist seawater chloride attack through the splash zone. Detail in marine engineering and seawater corrosion.
HF alkylation equipment foundations: Monel 400 is the default bolting on HF-wetted flanges per API RP 751. Foundation anchors for HF alkylation pumps, drums and exchangers match nickel-copper chemistry to the flange bolting to hold a single corrosion potential at the equipment skirt. Detail in HF acid resistance and HF alkylation.
Naval crane bases and deck-mounted equipment: Magnetic permeability of Monel 400 stays below 1.001 in the annealed condition, qualifying the anchor for non-magnetic hardware on minesweepers and degaussing-coil installations. Headed and swedged geometries dominate naval specifications because the structural pour is shallow over deck plating.
Frequently Asked Questions
L-bolt versus J-bolt versus swedged? L-bolt suits shallow embedment with moderate pull-out (90 degree leg). J-bolt clears rebar interference (180 degree return). Headed anchor delivers the highest pull-out per inch of embedment. Swedged anchor develops bond along the full embedded length where rebar interference rules out hook geometries.
What is the standard length? Project drawing governs. Indicative: M16 in 200 to 600 mm; M24 in 300 to 900 mm; M36 in 500 to 1500 mm; 5/8 inch in 8 to 24 inch; 1 inch in 12 to 48 inch; 1-1/2 inch in 18 to 60 inch.
What embedment depth applies? Set by the structural engineer per ACI 318 Chapter 17. Typical cast-in headed anchors run 8 to 12 times the shank diameter. Pull-out is concrete-governed because the F468 Class A tensile floor (70 to 130 ksi) exceeds typical concrete cone breakout capacity.
Related Products and Specifications
Companion pages: Monel 400 bolts (F468 hub), foundation bolts (heavier section), threaded rod (cut-to-length anchor rod), U-bolts, eye-bolts, stud bolts, and ASTM F468 specification. The nickel-copper alloy family covers metallurgy across Monel 400 / R-405 / K-500.
Request for Quote
Send geometry, shank diameter, embedded length, projecting thread length, spec, drawing reference and quantity to info@torqbolt.com or WhatsApp +91-22-66157017. Ex-Mumbai price and lead time returned within one working day. Domestic India 3 to 7 working days; export through JNPT. Each shipment carries EN 10204 type 3.2 plus the NACE MR0175 statement when sour service is specified.
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