polysius® Apron feederReliable feeding for the toughest application

The rugged RKF feeder that keeps hammer, impact, roll-sizer and roller crushers fed — and the maintenance and revamp programme that keeps it running for the next decade.

apron feeders in operation
more than
500
frequency-controlled capacity
up to (in t/h)
14000
up to width × length
3 x (in m)
30
inclination range
in (°) 0-
30

Different feeders for different requirements

Feeders aren't all the same. The polysius® RKF apron feeder is built for the toughest duty — feeding crushers with run-of-mine lumps, dosing material to downstream processes, and running wherever bulk materials have to be conveyed, in cement, lime, energy, sugar and beyond.

Duty: Feeds hammer, impact, roll-sizer and roller crushers; dosing and silo discharge.
Size: Built up to 3 m wide and 30 m long, in horizontal and inclined layouts.
Capacity: Frequency-controlled conveying extending above 14,000 t/h.
Incline: Special apron design realises inclination angles from 0° to 30°.
Running gear: Lifetime-lubricated tractor chains and rollers, sizes D4 to D11, matched to the toughness of the task.

Seven parts, one dependable machine.

Every apron feeder is built from the same well-proven building blocks — designed for a long, low-maintenance life.

Apron feeder pans

Single pans with a formed sealing lip that keeps fines out of the lower section.

Crawler / tractor chain

Lifetime-lubricated, sealed chain in sizes D4–D11, with repair links on hand.

Upper & lower rollers

Sealed, lifetime-lubricated rollers — no re-greasing in service.

Drive sprockets

Segmented, flame-hardened cast-steel sprockets renewed easily in situ.

Slide rails

Graphite-casting rails that take the wear — and need no grease.

Drive & tail station

Robust drive and tensioning at either end of the feeder.

Feeder structure

The heavy steel frame that carries it all under the harshest conditions.

Built to be serviced

Self-aligning, modular parts — swap wear items without stopping the line.

Option Items

Automatic lubration system can be reducing maintenance effort and supporting reliable long-term operation; Vibration sensors

What to replace – and what to check.

A handful of wear parts carry the load. Keep an eye on them, and the feeder rewards you with availability and lower energy use. Here's what each part is, and the best-practice check for it.

Drive sprockets

Renewed easily in situ thanks to the segmented design — no full teardown to replace the teeth.

Best-practice check

Visual check for cracks and broken teeth
Check power consumption
Do not reuse screws

Single pans

A formed sealing lip stops fines passing into the lower section; a square bar on top eases transport.

Best-practice check

Visual check for cracks and broken teeth
Check power consumption to avoid feeder damage

Slide rails

Graphite-casting rails take the wear (≈10 mm) and come in 1,500 mm lengths for quick replacement.

Best-practice check

Visual check of the 2–3 mm gap between pan and rail
Check power consumption to avoid feeder damage

Upper & lower rollers

Sealed, lifetime-lubricated rollers need no further lubrication. All common brands available (diameters vary by brand).

Best-practice check

Visual check that rollers still rotate
Check power consumption to avoid feeder damage

Tractor chain

Lifetime-lubricated, sealed tractor chain. A repair link is available to fix an urgent situation fast.

Best-practice check

Visual check of single links for cracks
Check chain tension
Check power consumption to avoid feeder damage

How to upgrade your polysius® apron feeder.

Bring an ageing feeder — ours or a third party's — back to life. Lower OPEX at low CAPEX, reduce energy, and invest for the next decade.

Update the drive system

From hydraulic to electromechanical drive with frequency converter

Up to 50% less investment than a new hydraulic drive
Decreased maintenance and downtime
Less power consumption from the frequency-controlled drive
No hydraulic expert required for further maintenance

Revamp of the complete feeder

Improve your production — the solution is based on your existing design

Reduction of maintenance costs and time
Safety improvement through less maintenance
Short plant downtime of just 2–4 weeks
Higher availability and lower power consumption from lifetime-lubricated parts

Revamp solutions for all feeders — sized to your plant and budget.

Scope	Example conversion	Where
Small	Renovation to RKF 2,000 × 10,750 – D7	Honduras
Medium	Convert PB to RKF 2,000 × 11,900 – D6	Germany
Maximum	Convert PB to RKF 1,500 × 9,500 – D4	Germany

Reference: Apron Feeder Modernizations – Honduras & Germany

The projects in Honduras and Germany show how existing installations can be upgraded to modern performance and reliability standards while maximizing component reuse.

In Honduras, an existing feeder was converted to an RKF 2,000 x 10,750-D7. In central Germany, a cement plant apron feeder was fully modernized under extremely challenging conditions, including winter temperatures down to –20 °C. Further projects in Germany included conversions to RKF 2,000 x 11,900-D6 and RKF 1,500 x 9,500-D4. The modernization concept focused on replacing wear-intensive components while retaining major structural elements wherever possible. Newly designed single-pan apron plates with integrated sealing lips prevent material leakage and protect downstream components. Plate thicknesses of 10 to 30 mm ensure high resistance to impact and abrasion.

A well-maintained machine consumes less energy.

Every check above protects availability and keeps power consumption where it belongs — the cheapest tonne per hour is the one you don't lose to downtime.

Contact Our Specialists

Third-party upgrade

From just a feeder to a polysius® RKF. We integrate our core technology into your existing plant and bring obsolete feeders back to life — investing for the next decade.

Tailor-made integration

High engineering standard for RKF integration into the existing plant, with an advanced 3D scan as the engineering basis where needed.

Lower OPEX, low CAPEX

Decrease operating costs at modest capital outlay — with capacity increases possible, and local sourcing of steel parts while Polysius focuses on the core parts.

Back to life

Bring an obsolete feeder back to life by renewing the core parts or a complete overhaul, and cut energy use with an updated drive concept.

What we need to know to improve your feeder.

Share a few operating parameters and our team will come back with the right maintenance or revamp path for your machine — new, existing or third-party.

Prefer to talk? Our apron-feeder specialists reply within two working days.

Group Leader Technical Sales and Project Coordination Service Cement RevampsTim Hücking

Telephone +492525994233

E-mail

Links & Downloads

Brochure Apron feeders pdf | 579 kb Brochure Apron feeder modernizations & converts pdf | 1.3 mb

Reliable feeding for

the toughest application.