Pignoni in ghisa standard europeo | GG22-GG25 DIN 8187 Diametro grande

06B – 24B

Chain Size Range

Z=30 – 150

Tooth Count Range

GG22 – GG25

Grey Cast Iron Grade

ISO 9001

Qualità certificata

Korea Ever-Power cast iron sprockets cover the large-diameter, high tooth count end of the European standard sprocket range — chain sizes 06B through 24B, tooth counts Z=30 to Z=150, in simplex, duplex and triplex configurations to DIN 8187 / ISO R606. These are the correct choice for slow-speed, heavy-load industrial drives where large pitch circle diameters are required and where the operating environment makes carbon steel sprockets unsuitable or uneconomical.

The material is grey cast iron to grade GG22–GG25 (EN-GJL-220 to EN-GJL-250). Grey cast iron has a lamellar graphite microstructure that gives it properties quite different from carbon steel: the graphite lamellae act as an internal solid lubricant at the tooth contact surface, providing inherent wear resistance without external hardening. This is particularly valuable in dusty, abrasive or poorly lubricated environments where a ground-smooth carbon steel tooth flank would be rapidly abraded, but the cast iron surface — slightly porous and graphite-rich — retains a lubrication film and resists micro-abrasion far better.

All cast iron sprockets are surface phosphated after casting and machining. Phosphating converts the outer surface layer to iron phosphate — a tightly adherent, oil-retaining conversion coating that provides a degree of corrosion protection and lubricant retention on the tooth flanks and bore surfaces. It does not add dimensional build-up (typically 1–5 µm thickness) and does not require any correction to bore tolerances after treatment.

Cast iron sprockets are stock bore as standard — bore machined to your shaft diameter on order. All sizes up to 12B are also available from our taper bore European range in cast iron (-CI suffix). For the small-tooth-count carbon steel equivalent covering Z=8 to Z=57, see our European standard stock bore sprockets. Pair with European standard roller chain in DIN 8187 for a matched, factory-direct drive.

⚠️

Speed limitation: Grey cast iron is brittle — it has essentially zero ductility and will fracture rather than deform under impact. Cast iron sprockets must not be used on drives above 50 rpm at the sprocket, or on drives with heavy shock loading (e.g. crusher start-up). For higher-speed or shock-load applications, use the carbon steel range. Cast iron is a slow-speed, steady-load, abrasive-environment material choice.

Caratteristiche tecniche

Quarry, Mining & Cement Plant

Slow primary conveyor drives in stone crushing, limestone quarrying and cement raw material handling. Large-diameter cast iron sprockets on 16B and 24B chain are standard for bucket elevator drives and pan conveyor head drives in these environments. The combination of abrasion resistance, vibration damping and low cost at large diameter makes cast iron the material of choice in these applications. See the full sprocket range for other drive options.

Grain Handling & Agricultural Processing

Grain elevator leg drives, grain cleaner chain drives and feed mill conveyor systems use large-diameter cast iron sprockets extensively. The abrasive nature of grain chaff, dust and grit makes cast iron's graphite surface far more wear-resistant than polished carbon steel under the poorly lubricated conditions typical of these drives. Z=57 to Z=95 in 10B and 12B are common specifications in this sector.

Woodworking & Forestry Equipment

Sawmill log deck chains, debarker conveyors and chip conveyor drives in saw dust and bark chip environments. Sawdust is a fine abrasive that destroys polished steel tooth flanks rapidly — cast iron's self-lubricating graphite surface resists this well. The vibration damping of cast iron also helps in sawmill drives where the chain drive transmits the pulsating torque of a circular saw or bandsaw.

Matching Heavy-Duty Drive Chain

Large cast iron sprockets are most often paired with heavy-duty or standard European standard roller chain in DIN 8187. For 16B and 24B drives, H-series heavy chain or multi-strand chain is common. Standard and H-series duplex and triplex chain in all sizes available.

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★★★★★

"We run 12B-1 chain on large cast iron sprockets Z=76 on our limestone elevator drives. Previous carbon steel sprockets at this size were outrageously expensive and wore out in 8 months in our dusty conditions. Korea Ever-Power GG25 cast iron at the same size has now run 22 months and the tooth profile is still within gauge. The phosphated surface retains chain oil far better than machined steel."

G.B., Maintenance Engineer
Italy – Limestone Processing Plant

★★★★★

"We needed 16B-2 duplex cast iron sprockets at Z=95 for a slow bucket elevator drive — 933 mm tip diameter. Nobody else quoted from stock inside 8 weeks. Korea Ever-Power produced and shipped in 4 weeks. The casting quality and bore tolerance were correct. We have since placed a standing order for annual supply."

D.F., Procurement Manager
Poland – Grain Elevator OEM

★★★★★

"Our sawmill uses 10B-1 chain on Z=57 cast iron sprockets throughout the log deck and green chain conveyor system. Sawdust here is extremely abrasive. After three years with Korea Ever-Power GG25 sprockets, we have had no tooth profile failures. Previously steel sprockets needed replacement every 18 months. The vibration reduction was also noticeable — the drive runs markedly quieter."

H.L., Plant Manager
Sweden – Sawmill

Request a Quote for Cast Iron Sprockets

Specify chain size, tooth count, strand (simplex/duplex/triplex) and required bore diameter. Large-diameter and non-catalogue tooth counts available to order. OEM quantities with material certificates welcome. Response within one working day.