{"product_id":"r4-offshore-mooring-chain","title":"Grade R4 Offshore Mooring Chain — Stud Link","description":"\u003ch2\u003eGrade R4 Offshore Mooring Chain\u003c\/h2\u003e\n\u003cp\u003eThe workhorse of deep-water mooring. Higher tensile strength and better fatigue resistance, for long-term offshore deployments on floating production units.\u003c\/p\u003e\n\u003cp\u003eStud link offshore mooring chain to \u003cstrong\u003eIACS UR W22\u003c\/strong\u003e, grade\n\u003cstrong\u003eR4\u003c\/strong\u003e, in diameters from 50 mm to\n90 mm. Quoted on request.\u003c\/p\u003e\n\n\u003ch3\u003eMechanical properties\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003ctr\u003e\n\u003cth\u003eYield stress, minimum\u003c\/th\u003e\n\u003ctd\u003e580 N\/mm²\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eTensile strength, minimum\u003c\/th\u003e\n\u003ctd\u003e860 N\/mm²\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eElongation, minimum\u003c\/th\u003e\n\u003ctd\u003e12%\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eReduction of area, minimum\u003c\/th\u003e\n\u003ctd\u003e50%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eLoads, weight and pitch\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eDiameter\u003c\/th\u003e\n\u003cth\u003eProof load\u003c\/th\u003e\n\u003cth\u003eBreak load\u003c\/th\u003e\n\u003cth\u003eWeight\u003c\/th\u003e\n\u003cth\u003e5-link pitch\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e50 mm\u003c\/strong\u003e (1.97 in)\u003c\/td\u003e\n\u003ctd\u003e2,160 kN\u003cbr\u003e220 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e2,740 kN\u003c\/strong\u003e\u003cbr\u003e279 t\u003c\/td\u003e\n\u003ctd\u003e54.8 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,100–1,128 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e52 mm\u003c\/strong\u003e (2.05 in)\u003c\/td\u003e\n\u003ctd\u003e2,327 kN\u003cbr\u003e237 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e2,952 kN\u003c\/strong\u003e\u003cbr\u003e301 t\u003c\/td\u003e\n\u003ctd\u003e59.2 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,144–1,173 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e54 mm\u003c\/strong\u003e (2.13 in)\u003c\/td\u003e\n\u003ctd\u003e2,499 kN\u003cbr\u003e255 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e3,170 kN\u003c\/strong\u003e\u003cbr\u003e323 t\u003c\/td\u003e\n\u003ctd\u003e63.9 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,188–1,218 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e56 mm\u003c\/strong\u003e (2.20 in)\u003c\/td\u003e\n\u003ctd\u003e2,677 kN\u003cbr\u003e273 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e3,396 kN\u003c\/strong\u003e\u003cbr\u003e346 t\u003c\/td\u003e\n\u003ctd\u003e68.7 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,232–1,263 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e58 mm\u003c\/strong\u003e (2.28 in)\u003c\/td\u003e\n\u003ctd\u003e2,860 kN\u003cbr\u003e292 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e3,628 kN\u003c\/strong\u003e\u003cbr\u003e370 t\u003c\/td\u003e\n\u003ctd\u003e73.7 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,276–1,308 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e60 mm\u003c\/strong\u003e (2.36 in)\u003c\/td\u003e\n\u003ctd\u003e3,048 kN\u003cbr\u003e311 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e3,867 kN\u003c\/strong\u003e\u003cbr\u003e394 t\u003c\/td\u003e\n\u003ctd\u003e78.8 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,320–1,353 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e62 mm\u003c\/strong\u003e (2.44 in)\u003c\/td\u003e\n\u003ctd\u003e3,242 kN\u003cbr\u003e331 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e4,112 kN\u003c\/strong\u003e\u003cbr\u003e419 t\u003c\/td\u003e\n\u003ctd\u003e84.2 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,364–1,398 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e64 mm\u003c\/strong\u003e (2.52 in)\u003c\/td\u003e\n\u003ctd\u003e3,440 kN\u003cbr\u003e351 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e4,364 kN\u003c\/strong\u003e\u003cbr\u003e445 t\u003c\/td\u003e\n\u003ctd\u003e89.7 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,408–1,443 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e66 mm\u003c\/strong\u003e (2.60 in)\u003c\/td\u003e\n\u003ctd\u003e3,643 kN\u003cbr\u003e372 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e4,621 kN\u003c\/strong\u003e\u003cbr\u003e471 t\u003c\/td\u003e\n\u003ctd\u003e95.4 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,452–1,488 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e68 mm\u003c\/strong\u003e (2.68 in)\u003c\/td\u003e\n\u003ctd\u003e3,851 kN\u003cbr\u003e393 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e4,885 kN\u003c\/strong\u003e\u003cbr\u003e498 t\u003c\/td\u003e\n\u003ctd\u003e101.3 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,496–1,533 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e70 mm\u003c\/strong\u003e (2.76 in)\u003c\/td\u003e\n\u003ctd\u003e4,064 kN\u003cbr\u003e414 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e5,156 kN\u003c\/strong\u003e\u003cbr\u003e526 t\u003c\/td\u003e\n\u003ctd\u003e107.3 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,540–1,579 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e73 mm\u003c\/strong\u003e (2.87 in)\u003c\/td\u003e\n\u003ctd\u003e4,392 kN\u003cbr\u003e448 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e5,572 kN\u003c\/strong\u003e\u003cbr\u003e568 t\u003c\/td\u003e\n\u003ctd\u003e116.7 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,606–1,646 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e76 mm\u003c\/strong\u003e (2.99 in)\u003c\/td\u003e\n\u003ctd\u003e4,731 kN\u003cbr\u003e482 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e6,001 kN\u003c\/strong\u003e\u003cbr\u003e612 t\u003c\/td\u003e\n\u003ctd\u003e126.5 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,672–1,714 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e78 mm\u003c\/strong\u003e (3.07 in)\u003c\/td\u003e\n\u003ctd\u003e4,962 kN\u003cbr\u003e506 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e6,295 kN\u003c\/strong\u003e\u003cbr\u003e642 t\u003c\/td\u003e\n\u003ctd\u003e133.2 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,716–1,759 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e84 mm\u003c\/strong\u003e (3.31 in)\u003c\/td\u003e\n\u003ctd\u003e5,682 kN\u003cbr\u003e579 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e7,208 kN\u003c\/strong\u003e\u003cbr\u003e735 t\u003c\/td\u003e\n\u003ctd\u003e154.5 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,848–1,894 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e87 mm\u003c\/strong\u003e (3.43 in)\u003c\/td\u003e\n\u003ctd\u003e6,056 kN\u003cbr\u003e618 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e7,682 kN\u003c\/strong\u003e\u003cbr\u003e783 t\u003c\/td\u003e\n\u003ctd\u003e165.8 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,914–1,962 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e90 mm\u003c\/strong\u003e (3.54 in)\u003c\/td\u003e\n\u003ctd\u003e6,439 kN\u003cbr\u003e657 t\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e8,167 kN\u003c\/strong\u003e\u003cbr\u003e833 t\u003c\/td\u003e\n\u003ctd\u003e177.4 kg\/m\u003c\/td\u003e\n\u003ctd\u003e1,980–2,030 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cem\u003eProof and break loads calculated from the IACS UR W22 formulas. Tonnes\nare metric tonnes-force, given for comparison — the specification works in\nkN.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003eAny diameter, not just the ones listed\u003c\/h3\u003e\n\u003cp\u003eW22 does not publish a load table — it publishes formulas, so the figures\nabove are calculated rather than looked up and we can quote a diameter that is\nnot on the list. For \u003cstrong\u003eR4 stud link\u003c\/strong\u003e, with \u003cem\u003ed\u003c\/em\u003e in\nmillimetres and the result in kN:\u003c\/p\u003e\n\u003ctable\u003e\n  \u003ctr\u003e\n\u003cth\u003eProof load\u003c\/th\u003e\n\u003ctd\u003e0.0216 × d² × (44 − 0.08d)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eBreak load\u003c\/th\u003e\n\u003ctd\u003e0.0274 × d² × (44 − 0.08d)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eWeight, stud link\u003c\/th\u003e\n\u003ctd\u003e0.0219 × d² kg\/m\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eFive link pitch\u003c\/th\u003e\n\u003ctd\u003e22d minimum, 22.55d maximum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003cp\u003eStudless chain is available in every grade. Its break loads are identical to\nstud link; the proof loads are lower above R3, and weight is calculated per\ndesign and submitted to class. Studless is normally deployed once, for permanent\nmoorings with a predetermined design life (W22 §1.1.3).\u003c\/p\u003e\n\n\u003ch3\u003eAccessories — do not substitute anchor chain parts\u003c\/h3\u003e\n\u003cp\u003eW22 covers the mooring accessories as well as the chain: common stud and\nstudless links, connecting common links, enlarged links, end links, detachable\nconnecting links, end shackles, subsea connectors, swivels and swivel shackles.\nKenter shackles are covered too, with their own machining requirement — the\nfillet radius must be at least 3 percent of nominal diameter (§3.1.3).\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eThey are made to the R grade, and they are not interchangeable with\nanchor chain accessories.\u003c\/strong\u003e W22 §1.2.3 is explicit that each grade is\napproved individually and that approval for a higher grade does not constitute\napproval of a lower one, and §1.6.1 requires the forge or foundry supplying\naccessories to be separately approved by the Classification Society. A Grade 3\nKenter made for anchor chain is not an R4 mooring Kenter, whatever the diameter\nsays.\u003c\/p\u003e\n\u003cp\u003eLooking for ship's anchor chain rather than offshore mooring? That is\nGrade 1\/2\/3 to IACS UR A1 — see\n\u003ca href=\"\/collections\/stud-link-anchor-chain\"\u003estud link anchor chain\u003c\/a\u003e and the\n\u003ca href=\"\/collections\/lr-kenter-shackles\"\u003eKenter joining shackles\u003c\/a\u003e that go\nwith it.\u003c\/p\u003e\n\n\u003ch3\u003eORQ — the name this used to have\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eORQ, \"Oil Rig Quality\"\u003c\/strong\u003e, is the older name for offshore\nmooring chain, from before IACS formalised the R grades. It still turns up\nconstantly in enquiries, drawings and rig inventories, and it sits at the bottom\nof the modern range — broadly where \u003cstrong\u003eR3\u003c\/strong\u003e is now.\u003c\/p\u003e\n\u003cp\u003eIf your specification, your rig drawing or your old certificate says ORQ, we\ncan quote it. See \u003ca href=\"\/pages\/orq-and-oversize-mooring-chain\"\u003eORQ and\noversize mooring chain\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ch3\u003eLarger than 90 mm\u003c\/h3\u003e\n\u003cp\u003eThe sizes listed match the diameters we carry across the rest of the range,\nso every chain size has a \u003ca href=\"\/collections\/lr-kenter-shackles\"\u003eKenter\njoining shackle\u003c\/a\u003e to pair with it. \u003cstrong\u003eAbove 90 mm the chain is made to\norder\u003c\/strong\u003e — W22's own tolerance bands run to 222 mm and the formulas above\nhold the whole way, so we can quote any diameter exactly.\n\u003ca href=\"\/pages\/orq-and-oversize-mooring-chain\"\u003eTell us what you need\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ch3\u003eCertification\u003c\/h3\u003e\n\u003cp\u003eSupplied with Classification Society certification. Chain is manufactured in\ncontinuous lengths by flash butt welding and heat treated in a continuous\nfurnace — batch heat treatment is not permitted (§3.2.1.1). Link shape and\nproportion conform to \u003cstrong\u003eISO 1704\u003c\/strong\u003e or a specially approved design.\u003c\/p\u003e\n\u003cp\u003eTell us the grade, the diameter, the length and the society, and we will quote\nit delivered.\u003c\/p\u003e","brand":"Dibblee","offers":[{"title":"50 mm — break 2,740 kN (279 t)","offer_id":50201027641621,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"52 mm — break 2,952 kN (301 t)","offer_id":50201027674389,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"54 mm — break 3,170 kN (323 t)","offer_id":50201027707157,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"56 mm — break 3,396 kN (346 t)","offer_id":50201027739925,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"58 mm — break 3,628 kN (370 t)","offer_id":50201027772693,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"60 mm — break 3,867 kN (394 t)","offer_id":50201027805461,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"62 mm — break 4,112 kN (419 t)","offer_id":50201027838229,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"64 mm — break 4,364 kN (445 t)","offer_id":50201027870997,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"66 mm — break 4,621 kN (471 t)","offer_id":50201027903765,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"68 mm — break 4,885 kN (498 t)","offer_id":50201027936533,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"70 mm — break 5,156 kN (526 t)","offer_id":50201027969301,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"73 mm — break 5,572 kN (568 t)","offer_id":50201028002069,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"76 mm — break 6,001 kN (612 t)","offer_id":50201028034837,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"78 mm — break 6,295 kN (642 t)","offer_id":50201028067605,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"84 mm — break 7,208 kN (735 t)","offer_id":50201028100373,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"87 mm — break 7,682 kN (783 t)","offer_id":50201028133141,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"90 mm — break 8,167 kN (833 t)","offer_id":50201028165909,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}],"url":"https:\/\/www.kentershackle.com\/products\/r4-offshore-mooring-chain","provider":"Kenter Shackles","version":"1.0","type":"link"}