STAINLESS STEEL HEAVY HEXAGON FULL NUTS UNI 5587

Heavy Hexagon Full Nuts UNI 5587 — UNI 5587 is the Italian national standard for a heavy-series full nut, defining a thicker-section body than the equivalent DIN 934 or ISO 4032 nut at the same nominal thread size, giving extra thread engagement and a larger bearing area for joints carrying higher clamping loads than a standard nut is really sized for. That extra section works the same way as any heavy series specification — DIN 6330 or the ASME heavy series serve the same purpose under different national standards — by giving a higher-grade or larger bolt more engaged thread to actually develop its full rated strength, rather than the nut itself becoming the weak point in a high-tensile joint. UNI 5587 turns up specifically on structural, marine, and heavy engineering work where equipment, drawings, or specifications originating from Italian or wider European industrial standards call for it by name; outside of that context, DIN 6330 or an ISO/ASME heavy series equivalent generally covers the same functional need, so the choice mostly comes down to which standard a project's documentation specifies rather than any performance difference. Dimensions between UNI 5587 and its DIN or ASME counterparts are broadly similar but not guaranteed identical, so where a drawing specifically calls up UNI 5587, sourcing the actual standard rather than substituting a similar-looking heavy nut matters for anyone working to a QA-controlled specification. There's no locking feature built in — it's a plain heavy nut relying on standard friction and correct torque, so where the structural joint also needs vibration resistance, a separate locking method should be specified in addition. A2 stainless covers general heavy engineering indoor use; A4 is worth the extra cost for structural or marine applications exposed outdoors, given how often heavy-series nuts end up in long-service, hard-to-inspect connections. Sizing follows the mating high-tensile bolt's diameter, pitch, and grade, with the nut's property class checked against the bolt's stated strength.

FAQs
Is UNI 5587 dimensionally identical to DIN 6330?
Broadly similar, since both are heavy-series hexagon nuts serving the same purpose, but they originate from different national standards and dimensions aren't guaranteed identical, so where a drawing specifically calls for UNI 5587, that standard should be sourced rather than substituted.

Why would a UK project specify an Italian standard nut?
Most commonly because the original equipment, drawings, or a wider European specification originated from an Italian or continental European source and calls up UNI 5587 by name, rather than any UK-specific reason to prefer it over a DIN or ISO equivalent.

How does UNI 5587 compare to DIN 6330?
Both are heavy-series hexagon nuts offering greater thread engagement than standard nuts, but they originate from different national standards (Italian UNI versus German DIN) and may differ in exact dimensions; the applicable standard should be confirmed against the drawing.

Is UNI 5587 self-locking?
No, it is a plain heavy hexagon nut relying on standard friction and correct torque, with no built-in locking feature.