Leaf Chains and Hoisting Chains

Korea Ever-Power leaf chains are high-strength pin-and-plate assemblies designed for tension applications rather than power transmission. Unlike roller chains, a leaf chain carries its full load through stacked link plates pinned together without a bush or roller – making the structure compact, highly flexible, and capable of extremely high tensile loads in a narrow profile suited to the confined spaces inside forklift mast channels. BL and LH series leaf chains for forklift mast assemblies, industrial door drives, counterweight systems, and hoist mechanisms. Minimum breaking loads from 11.1 kN to over 1,600 kN. Manufactured to ISO 4347 and ANSI B29.8 standards.

Категория:

11.1 kN

Min. Breaking Load

1,600+ kN

Max. Breaking Load

ISO 4347

and ANSI B29.8

5:1

Safety Factor

Leaf Chain and Hoisting Chain - Product Overview

The EP range includes two series. BL series chains follow ANSI B29.8, the dominant standard in North America and Korea, and are specified by a two-digit code indicating pin diameter class and link plate count per link (e.g. BL622 means 6/8-inch pitch, 2-by-2 plate lacing). LH series chains follow the ISO 4347 European designation and share dimensional compatibility with many European forklift OEM specifications. Both series are manufactured from alloy steel plates and through-hardened pins, with each chain pre-tested at proof load before leaving the production line.

Applications extend beyond forklifts into industrial vertical door counterweights, crane hoist blocks, tensioning mechanisms on press beds, and load-levelling devices on automotive assembly fixtures. For any application requiring a maintenance replacement, the EP chain model number and pitch can be cross-referenced directly to the OEM part number on request.

Korea Ever-Power leaf chains and hoisting chains BL LH series product

Leaf Chain vs Roller Chain - Key Differences

A leaf chain is purely a tension member. It has no rollers and no bushes - only interleaved inner and outer link plates clamped by hardened pins. This allows far more plates to be stacked onto a single pin than would fit in a roller chain of the same pitch, producing breaking loads several times higher at the same pitch dimension. The absence of rollers also removes the need for any rotational clearance between bush and roller, which means the chain can fold much more tightly around small pulley or sheave diameters - important in the tight space envelope of a forklift mast.

However, a leaf chain cannot transmit rotational power through a sprocket tooth engagement. It is always used over a plain cylindrical drum, a guide sheave, or a slotted anchor pin. The practical upshot is that leaf chains appear almost exclusively in linear hoisting and tensioning applications, never in rotating drive trains.

Leaf Chain Anatomy

Link Plates

Stamped alloy steel; multiple plates per link for load capacity

Pin

Through-hardened alloy; primary shear and bending member

Lacing Ratio

2x2, 3x3, 4x4, 6x6 etc; higher ratios give greater strength

Anchor Pin / Clevis

End fitting connecting chain to mast carriage or ram

 

BL Series Leaf Chain Specifications - EP-BL4 to EP-BL8

Standard: ANSI B29.8. All dimensions in mm. Minimum breaking load (MBL) is per chain strand at proof load. The BL number consists of pitch class and lacing designation (e.g. BL623 means 19.05 mm pitch, 2x3 lacing).

leaf-chains-dismension-1

EP Model Pitch (mm) Pin Dia. (mm) Plate Width (mm) Plate Thickness (mm) Min. Breaking Load (kN) Wt. (kg/m)
EP-BL422 12.70 4.45 7.92 1.52 11.1 0.27
EP-BL434 12.70 4.45 7.92 1.52 20.0 0.41
EP-BL444 12.70 4.45 7.92 1.52 24.5 0.47
EP-BL446 12.70 4.45 7.92 1.52 28.9 0.54
EP-BL522 15.875 5.08 9.53 1.93 17.8 0.40
EP-BL534 15.875 5.08 9.53 1.93 31.1 0.62
EP-BL544 15.875 5.08 9.53 1.93 37.8 0.72
EP-BL546 15.875 5.08 9.53 1.93 44.5 0.82
EP-BL622 19.050 5.94 12.07 2.42 26.7 0.58
EP-BL623 19.050 5.94 12.07 2.42 33.4 0.69
EP-BL634 19.050 5.94 12.07 2.42 44.5 0.88
EP-BL644 19.050 5.94 12.07 2.42 53.4 1.04
EP-BL646 19.050 5.94 12.07 2.42 62.3 1.20
EP-BL666 19.050 5.94 12.07 2.42 80.1 1.50
EP-BL688 19.050 5.94 12.07 2.42 106.8 2.00
EP-BL822 25.400 7.92 15.88 3.18 44.5 0.96
EP-BL834 25.400 7.92 15.88 3.18 75.6 1.48
EP-BL844 25.400 7.92 15.88 3.18 89.0 1.75
EP-BL846 25.400 7.92 15.88 3.18 107.0 2.05
EP-BL866 25.400 7.92 15.88 3.18 138.0 2.58
EP-BL888 25.400 7.92 15.88 3.18 178.0 3.28

LH Series Leaf Chain Specifications - EP-LH0822 to EP-LH2066

Standard: ISO 4347. LH designation uses pitch code and lacing configuration. LH0822 denotes 25.4 mm pitch (08 prefix), 2x2 lacing. LH2066 denotes 63.5 mm pitch (20 prefix), 6x6 lacing.

EP Model Pitch (mm) Pin Dia. (mm) Plate Width (mm) Plate Thickness (mm) Min. Breaking Load (kN) Wt. (kg/m)
EP-LH0822 25.40 7.92 15.88 3.18 44.5 0.96
EP-LH0834 25.40 7.92 15.88 3.18 75.6 1.48
EP-LH0844 25.40 7.92 15.88 3.18 89.0 1.75
EP-LH1022 31.75 9.53 19.05 4.00 66.7 1.55
EP-LH1034 31.75 9.53 19.05 4.00 111.2 2.43
EP-LH1044 31.75 9.53 19.05 4.00 133.4 2.88
EP-LH1222 38.10 11.10 22.23 4.80 89.0 2.18
EP-LH1234 38.10 11.10 22.23 4.80 150.0 3.43
EP-LH1244 38.10 11.10 22.23 4.80 178.0 4.00
EP-LH1634 50.80 14.27 28.58 6.35 267.0 6.67
EP-LH1644 50.80 14.27 28.58 6.35 320.0 7.85
EP-LH2034 63.50 19.05 36.45 7.94 480.0 11.80
EP-LH2044 63.50 19.05 36.45 7.94 578.0 13.92
EP-LH2066 63.50 19.05 36.45 7.94 800.0 18.80

BL vs LH Series - Comparison and Selection

Criterion EP-BL Series (ANSI B29.8) EP-LH Series (ISO 4347)
Standard ANSI B29.8 ISO 4347 / FEM 4.004
Primary markets USA, Korea, Japan, SE Asia Europe, UK, Australia, Middle East
Pitch range 12.70 mm to 25.40 mm (BL4 - BL8) 25.40 mm to 63.50 mm (LH08 - LH20)
Typical application Light to medium forklifts, 1 to 5 tonne capacity Medium to heavy forklifts, 3 to 20+ tonne
Lacing options 2x2 through 8x8 2x2 through 6x6
End fittings Anchor pin, clevis, or tab-end; OEM matched on request Anchor pin, clevis, or tab-end; OEM matched on request
OEM compatibility Toyota, Komatsu, Mitsubishi, Doosan forklift specs Linde, Jungheinrich, BT, Hyster/Yale specs

Five Manufacturing Advantages of EP Leaf Chains

100% Proof Load Testing

Every EP leaf chain is tensioned to proof load - typically 50% of minimum breaking load - before despatch. Any link showing deformation, cracking, or joint opening is removed from the batch. This is not sampling: it is a 100% test on every chain supplied.

Through-Hardened Alloy Pins

All EP leaf chain pins are through-hardened to HRC 48-52 using controlled atmosphere heat treatment. The hardness profile is verified on sample pins from each heat treatment batch. A surface-only hardened pin would fail by bending at the core under repeated shock loads typical of forklift operation.

Consistent Plate Stamping Tolerances

The pin holes of every plate are punched with a tolerance of plus or minus 0.01 mm. Loose pin holes cause fretting between plates and pins that generates iron oxide debris - the principal accelerator of leaf chain fatigue. Tight tolerances throughout the plate stack keep the chain straight, prevent premature side-plate cracking, and extend service life.

Lubricated Pins at Assembly

EP leaf chains are assembled with a penetrating lubricant applied to each pin before pressing. Unlike roller chains, leaf chains have no built-in oil reservoir. Without factory-applied lubricant in the pin-hole interface, a new chain begins dry and generates high wear from first use. Factory lubrication reduces the initial wear rate and bridges the gap until the maintenance programme begins.

Custom Length with End Fittings

EP leaf chains are supplied cut to length with OEM-specified end fittings pressed, welded, or pinned in place. Common fittings include threaded anchor pins with hex lock nuts, tab-end plates for sheave systems, and clevis ends for carriage attachment. End fitting dimensions are verified against the OEM drawing or sample before each order is cut.

Applications

Forklift Mast Assemblies

EP-BL and EP-LH chains are direct OEM-compatible replacements for forklift mast hoist chains on Toyota, Komatsu, Linde, Hyster, Yale, Mitsubishi, Doosan, BT, and Jungheinrich trucks from 0.5 tonne to 25 tonne. Both the free-lift and main hoist chain positions are covered. Chains are cut to the exact mast lift height and fitted with the appropriate anchor and clevis hardware.

Industrial Counterweight Systems

High-speed industrial vertical doors, machine tool quills, and press-bed counterbalance mechanisms use EP-LH1034 to EP-LH1644 chains running over steel sheaves. The chain must maintain dimensional stability under repeated tensile cycling without creep or measurable elongation. EP chains are tested to 10 million cycles at 30% of breaking load with no measurable joint play increase in pre-production type testing.

Hoist and Crane Reeving

EP-LH2034 to EP-LH2066 heavy leaf chains in the 63.5 mm pitch range are used in overhead crane hoist blocks, shipyard gantry chains, and mining cage suspension systems. Breaking loads over 800 kN on a single chain strand make these the highest-capacity tension components in the Korea Ever-Power range. Multi-strand reeving setups using two or four chains in parallel are standard for lift capacities above 30 tonnes.

Automotive Assembly Line Fixtures

Body-in-white carriers, powertrain assembly pallets, and precision vertical adjustment fixtures on automotive assembly lines use leaf chains because the high load capacity in a narrow section allows the fixture to carry vehicle body panels or engine blocks without the chain protruding beyond the fixture boundary. EP-BL644 and EP-BL646 are common in these applications.

Leaf Chain Inspection and Replacement Guidelines

Leaf chain failure in a forklift is a serious safety risk. The following guidelines reflect ISO 4347 and FEM 4.004 inspection requirements and should form the basis of a regular maintenance programme.

A

Check Chain Elongation

Measure 12 or 25 links at working tension. Replace when elongation exceeds 3% of nominal length. For BL622 at 19.05 mm pitch, 25 links nominal is 476.25 mm; replace at 490.5 mm or more.

B

Inspect for Cracked Plates

Clean the chain with a degreasing solvent and inspect every link plate for surface cracks, especially near the pin holes and at the waist of the plate. Any cracked plate is immediate cause for replacement regardless of elongation.

C

Check Pin Rotation

Mark pin ends and verify they have not rotated in the outer plates during operation. Pin rotation means the press fit has failed; the chain must be replaced immediately. Rotating pins generate rapid plate wear and can lead to sudden failure.

D

Lubricate at Every Service

Apply a chain lubricant with good penetration to the full chain length at every scheduled service - typically every 250 to 500 hours for forklifts operating in normal indoor environments. Use a spray applicator and allow the oil to penetrate into the pin holes before wiping off the excess.

Korea Ever-Power leaf chain quality inspection and service support

Related Products - Chains and Matching Sprockets

Korea Ever-Power sprockets and chain wheels for driving conveyor agricultural and engineering chains

Every chain in the Korea Ever-Power range has a matching sprocket available. Sprockets are manufactured in C45 carbon steel, ductile iron, and case-hardened alloy steel to suit the tooth form geometry of each specific chain series. Using a matched EP sprocket alongside an EP chain guarantees correct pitch engagement, consistent tooth load distribution, and maximum chain service life.

The sprocket range covers simplex, duplex, and triplex tooth profiles for standard A and B series roller chains; agricultural tooth forms for CA, CC, and S series chains; ISO 1977 tooth profiles for M series conveyor chains; and custom tooth forms for WH series engineering chains. Bore machining, keyway, set screw, taper lock, and QD bushing hub designs are all available. Standard bore sizes ship within 5 working days; finished-bore and special-hub sprockets ship within 10 working days.

View Matching Sprockets →

Korea Ever-Power driving chains A and B series roller chain

Driving Chains

A and B series short pitch precision roller chains for power transmission drives. Simplex to triplex, pitch 9.525 mm to 76.2 mm.

View Driving Chains

Korea Ever-Power engineering chains for heavy industrial conveying

Engineering Chains

Welded steel, cast iron, and forged chains for cement, steel, mining, and chemical conveying. Heavy-duty pitch range up to 300 mm.

View Engineering Chains

Korea Ever-Power stainless steel chain

Stainless Steel Chains

SUS304 and SUS316L roller chains for food, pharmaceutical, and chemical environments requiring corrosion resistance or washdown.

View SS Chains

Korea Ever-Power conveyor chains

Conveyor Chains

Small and large pitch conveyor chains, double pitch, attachment chains, and industry-specific conveyor solutions for packaging, food, and manufacturing.

View Conveyor Chains

Frequently Asked Questions

How do I identify the correct leaf chain for my forklift?
Three pieces of information determine the replacement chain: pitch (the distance between pin centres), lacing (the number and arrangement of plates per link), and the overall chain length with end fitting dimensions. The pitch and lacing code are usually stamped on the outer plates of the original chain - for example BL644 or LH1034. The chain length must be measured when the mast is at the bottom of its travel with the chain slack removed. If the original chain data plate is missing, supply the forklift model number and serial number and our technical team will cross-reference the OEM specification.
What is the recommended safety factor for a forklift leaf chain?
ISO 4347 and ANSI B29.8 both require a minimum design safety factor of 5:1 on leaf chains used in forklift mast applications - that is, the minimum breaking load of the chain must be at least five times the maximum load the chain will carry in service, including dynamic loads from acceleration, braking, and shock. In practice, most forklift OEMs design to a 5:1 or 6:1 factor. Korea Ever-Power BL and LH series chains are rated at their minimum breaking load per the respective standard, and the selection tables allow users to verify the working load does not exceed 20% of the MBL for a 5:1 factor.
How often should forklift leaf chains be replaced?
Replacement intervals depend on duty cycle, lubrication frequency, environment, and load profile. As a baseline, ISO 4347 recommends replacement when chain elongation reaches 3% of nominal length, or after any evidence of cracked plates, pin rotation, or corrosion - whichever comes first. In practical forklift maintenance programmes, heavily used trucks in 2-shift operation often reach the 3% elongation limit within 6,000 to 8,000 operating hours. Lightly used trucks may run 15,000 to 20,000 hours. Regular lubrication at 250-hour intervals is the single most effective way to extend chain life. As a precaution, many fleet operators on a mileage-based maintenance contract replace chains every 3 years regardless of measured elongation to eliminate the risk of a surprise failure.
Can a leaf chain be repaired by replacing individual links?
No. ISO 4347 and most forklift OEM service manuals prohibit the repair of a leaf chain by replacing individual links or pins. The reason is that the plates and pins of a leaf chain are press-fitted to a specific interference dimension that cannot be replicated in the field. A field-replaced pin would have insufficient interference and would fail in rotation, leading to rapid plate erosion. If any plate, pin, or link is damaged, the entire chain must be replaced with a new chain of the same designation. On a forklift mast, both chains on a duplex mast should be replaced at the same time - replacing only one chain introduces an asymmetric load that accelerates failure on the older chain.
What lubricant is correct for a leaf chain?
A low-viscosity chain oil with good penetrating properties and rust-inhibiting additives is the correct lubricant for leaf chains. The oil must be thin enough to penetrate into the pin-hole clearance by capillary action; heavy gear oils or greases sit on the surface and provide no benefit at the interface where wear actually occurs. In mast environments where oil drip onto the floor is unacceptable, a wax-based or dry-film chain lubricant is acceptable if reapplied frequently. Avoid any lubricant containing solvents that attack the paint or seals of adjacent hydraulic components. For food-industry pallet trucks, NSF H1-approved white mineral chain oil is the correct product.
Do you supply leaf chains with custom lengths and end fittings?
Yes. Korea Ever-Power supplies EP leaf chains cut to any length from 0.5 m to 20 m, with end fittings pressed, peened, or bolted in place to OEM or customer drawing. Common end fittings in stock include M8 through M48 threaded anchor pins with hex nuts, clevis ends with drilled pin holes, tab-end plates, and weld-on anchor plates. Custom fittings not in the standard range can be machined to drawing for orders above a minimum quantity. Please supply the chain designation, overall length measured between pin centres of the end fittings, and a sketch or dimension sheet of the end fittings required when requesting a quotation.

What Our Customers Say

★★★★★

"We maintain a 120-truck Toyota and Linde fleet and switched to Korea Ever-Power EP-BL646 and EP-LH1034 chains three years ago. Elongation at the 6,000-hour mark averaged 1.8%, below our 3% threshold. We extended the replacement interval from 4,000 to 6,000 hours, which cut chain costs significantly."

P.W., Fleet Maintenance Manager
Australia - Logistics and Distribution

★★★★★

"Our vertical door counterweight system runs EP-LH1234 chains over 400 mm sheaves at 1,200 cycles per day. After 18 months of continuous operation there was no measurable plate cracking or pin rotation on any of the 16 chains in service. We carried out the first lubrication interval at 500 hours as recommended and the chains remain in excellent condition."

F.M., Maintenance Supervisor
Germany - Automotive Assembly Plant

★★★★★

"We ordered EP-BL622 chains cut to length with threaded anchor pin ends matched to our Hyster S7.0 specifications. The chains arrived dimensionally correct with the OEM anchor pin thread pitch, and the 100% proof load certificate was included in the delivery paperwork. No issues in 12 months of heavy port use."

C.A., Workshop Manager
South Korea - Container Port Operations

★★★★★

"The EP-LH2044 chains on our 20-tonne overhead crane reeving replaced chains from a European supplier at a significantly lower unit cost. The material certificates matched our procurement requirements and the chains passed our incoming inspection load test at 300 kN without any joint movement."

H.J., Chief Engineer
Netherlands - Heavy Steel Fabrication

Request a Quotation for EP Leaf Chains

Supply the chain designation (BL or LH model number), quantity, overall length, end fitting type, and forklift or equipment model. Our team cross-references OEM specifications and responds within one business day.

Детали

Editor

Cxm