Brand: Flender

Flender ELPEX Highly Flexible Couplings ELPEX, ELPEX-B, ELPEX-S

Name: Flender ELPEX Highly Flexible Couplings – Datasheet & Quote
Brand: Flender
SKU: ELPEX

Description

Highly flexible couplings for engine drives and non-uniform torque: ELPEX, ELPEX-B and ELPEX-S

The Flender ELPEX series groups three highly flexible coupling families from catalog FLE 10.3 (edition 2026.1): ELPEX with split flexible rings, ELPEX-B with an elastic tire, and ELPEX-S with rubber disk elements. Flender says their low torsional stiffness and damping capacity make them especially suitable for coupling machines with a highly non-uniform torque pattern, and ELPEX and ELPEX-B are free of torsional backlash.

Typical uses given in the catalog include mill drives in the cement industry, marine main and secondary drives, large excavators driven by an electric motor or diesel engine, and, for ELPEX-S, diesel motor and reciprocating compressor drives. All three suit reversing operation and horizontal or vertical mounting.

Technical specifications

Parameter	Specification
Catalog	Flender FLE 10.3, Edition 2026.1
ELPEX (flexible ring)	9 sizes, rated torque 1,600 Nm to 90,000 Nm; natural rubber 70 Shore A; -40 to +80 C; types ENG, EFG, ENGS and EFGS (fail-safe)
ELPEX-B (elastic tire)	15 sizes, rated torque 57 Nm to 19,000 Nm; natural rubber -50 to +55 C or chloroprene (FRAS) -15 to +70 C; types EBWN, EBWT, EBWZ
ELPEX-B size 105 / 630	Rated torque 57 Nm / 19,000 Nm; maximum torque 114 / 38,000 Nm; max speed 5,400 / 1,200 rpm
ELPEX-B torsional data	Damping coefficient 0.9; fatigue torque 0.3 x rated; maximum torque 2 x rated; angle up to 4 degrees
ELPEX-S (rubber disk)	12 sizes, rated torque 330 Nm to 63,000 Nm in the catalog text; -40 to +80 C; four rubber versions per size; types ESN, ESD, ESDR, ESNR, ESNW, ESDW, EST
ATEX marking ELPEX-B	II 2G Ex h IIC T6…T5 Gb X; II 2D Ex h IIIC T85 C…100 C Db X; I M2 Ex h Mb X
ATEX marking ELPEX-S	II 2G Ex h IIC T4…T3 Gb X; II 2D Ex h IIIC T120 C…160 C Db X; I M2 Ex h Mb X (type EST not available in Ex version)
Metal parts	EN-GJL-250 grey cast iron, EN-GJS-400 spheroidal graphite cast iron or steel

How the three designs differ

ELPEX-B has a slit elastic tire fixed to the hubs with clamping rings, so the tire can be changed without moving the machines, and if it is irreparably damaged the metal parts rotate freely without contact. ELPEX uses split flexible rings with progressive torsional stiffness and an optional fail-safe device with cams, frequently required for marine drives. ELPEX-S uses vulcanised rubber disk elements with a linear stiffness; with substantial overload the rubber disk is irreparably damaged and the coupling throws the load, limiting the overload. Four rubber grades are offered per size to tune torsional vibration behaviour, and the ELPEX-S can also be built with a fail-safe device.

Selection notes

Check maximum torque, fatigue torque against dynamic load and frequency factor, maximum speed, shaft misalignment, bore and mounting geometry as described in the catalog. For ELPEX-S in explosive atmospheres the fatigue torque must be reduced by 70 or 50 percent depending on load, and type EST is not permitted. Coupling items are grouped in Electric Motors; a related published product is the Flender ONE gear unit.

Documents and quotation

The Flender document is attached. Seven Star LLC supplies Flender couplings on request and quotes against the exact type, size and bore. The attached PDF is the full catalog FLE 10.3; confirm the series, size and flywheel or flange connection before ordering. The ELPEX-S size range in the catalog text reads 330 to 63,000 Nm while the overview page lists 200 to 63,000 Nm, so check with the size table.

Datasheets & Documents

Datasheet Flender catalog FLE 10.3 Edition 2026.1 Highly Flexible Couplings (EN) Download

Reviews (0)

Reviews

There are no reviews yet.

How would you rate this product?

About brand

Large industrial gearboxes are the product most engineers associate with Flender, a company founded in 1899 and based in Bocholt, Germany, that builds gear units, couplings and drive systems. Seven Star LLC sources and supplies Flender gear units and their spare parts for mills, conveyors, pumps and marine drives in Oman, working from the nameplate data. On some nameplates the name appears as Siemens Flender.

Flender gearbox types listed here

Four items are listed. Flender ONE is the manufacturer's redesigned single-stage helical gear unit. The H2SV 09 is a two-stage helical gear unit of size 09 with a solid output shaft, shown here with a cooling coil and oil tank. The NAVILUS line covers marine gearboxes, listed in a multiple-input, single-output arrangement that brings several engines onto one propeller shaft, and in a version for dredgers. Flender couplings such as the flexible N-EUPEX type are often ordered with a gear unit.

Ordering a Flender gearbox or parts: what we need

Send a photo of the nameplate showing type, size, serial or order number, ratio, power and speeds. For spares, the serial number lets the parts list be traced, so add the item number of the bearing, seal or gear set you need. For a new unit, give the driven machine, motor power and speed, output speed, mounting position, shaft arrangement, ambient temperature and cooling method. Marine and dredger gearboxes for GCC yards also need the class society.

Browse Flender products by category: Electromotors, Electric Motors & Pumps.