PML
Magnetic Roller Separator
Magnetic Roller Separator
Starting from Rs.98,843
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Product Details
At a Glance
A magnetic roller separator (also called a roll-type magnetic separator or magnetic destoner) is a self-cleaning, high-intensity roller that removes fine and weakly-magnetic iron contamination from dry bulk material in continuous processing lines. PML's roller separators reach up to 14,000 Gauss, the highest intensity in PML's separator range, for continuous operation up to 80°C.
Fine, weakly-magnetic iron contamination is difficult to remove from dry bulk material without stopping the line to clean the separator constantly. The PML Magnetic Roller Separator — also known as a roll-type magnetic separator or magnetic destoner — is built for exactly that challenge: a high-intensity magnetic roller running up to 10,000 Gauss, capturing fine and weakly-magnetic particles continuously, with self-cleaning operation that keeps production running.
How It Works
Material is fed onto a conveyor belt via a feeder unit. At the discharge point, it enters the magnetic zone of the high-intensity NdFeB roller (which doubles as the head pulley). Magnetic particles are attracted and carried further along the belt before dropping into a dedicated collection chute once they clear the field; non-magnetic material continues forward as purified product. Because the roller itself does the separating as the belt runs, there's no separate cleaning cycle needed — it's continuous, self-cleaning operation by design.
Also a Magnetic Destoner
Beyond iron removal, the same system effectively removes small stones, soil particles and other metallic impurities from grains and similar bulk materials — a dual-purpose separator for grain and food processing lines.
Key Advantages
- Up to 10,000 Gauss
High enough field strength to capture fine and weakly-magnetic particles that lower-intensity separators miss.
- Single, Double or Triple Stage
Configure additional stages in series for progressively higher purity requirements.
- Continuous Self-Cleaning
No shutdowns for manual cleaning — separation happens continuously as the belt runs.
- Hygienic Contact Parts
Stainless steel contact parts available for food and pharmaceutical applications.
Construction
The system comprises a high-intensity NdFeB magnetic roller acting as the head pulley, a non-magnetic tail pulley, a conveyor belt in Kevlar or an application-specific material, a feeder unit, separate discharge chutes for magnetic and non-magnetic material, and a mild steel structural frame with stainless steel contact parts where hygiene requires it.
Where It's Used
Glass sand purification, mineral processing (quartz, silica, feldspar), food processing (grains, spices), chemical industries, and recycling or general bulk material handling. See how customers are using this equipment on our food & powder processing page, in grain, flour and feed handling on our grain, flour & feed page, in foundry and recycling on our foundry & recycling page, or in plastics and chemical processing on our plastics & chemical processing page.
Frequently Asked Questions
Single, double or triple stage — which do I need?
It depends on the purity level you need to hit. A single stage handles most standard separation needs; double or triple stages in series are used where output purity requirements are stricter.
Does it need manual cleaning?
No — the roller design is inherently self-cleaning as the belt runs continuously, unlike static magnetic separators that need periodic manual clearing.
Can it remove stones as well as iron?
Yes — the same system functions as a magnetic destoner, removing small stones and soil particles alongside metallic contamination from grains and similar materials.
What is the conveyor belt made from?
Kevlar, or an application-specific material selected to suit your process.
Is it suitable for food or pharma lines?
Yes — stainless steel contact parts are available where hygiene requires it, for food and pharmaceutical applications.
Why Buy From PML
- 65+ years of magnetic separation engineering — high-intensity separation systems for glass, mineral, food and chemical processing.
- Made and tested in-house — every roller is manufactured and checked to its stated Gauss rating.
- Configurable staging — single, double or triple stage systems built around your purity target.
- Magnetic calibration and audit services available to verify field strength over time.
Need help specifying the right stage configuration? Enquire now and our engineering team will size the right separator for your process.
Why Magnetic Strength Drops in Ferrous Separators (and When to Replace)
Separation efficiency falls as magnetic strength decreases. Below are the most common causes of reduced field strength in NdFeB (neodymium) magnetic separation equipment, along with the warning signs that indicate a magnet or separator needs replacing.
Causes of Reduced Magnetic Strength
- Thermal demagnetization: Standard Neodymium-Iron-Boron (NdFeB) grades lose magnetic strength when exposed to temperatures above their rating — often starting at 80°C / 176°F for standard grades. Exceeding these limits causes a permanent loss of magnetic flux.
- Corrosion and core oxidation: NdFeB is highly iron-rich and oxidizes quickly. If moisture, washdown liquids, or corrosive chemicals breach the outer stainless steel cladding, the magnet swells, crumbles, and loses field strength.
- Mechanical damage and internal cracking: NdFeB is brittle. Dropping magnetic tubes during cleaning, or subjecting them to heavy equipment vibration, causes internal micro-fractures that break the continuous magnetic circuit.
- Strong opposing magnetic fields: A sufficiently strong opposing field can overcome a material's coercivity and flip or randomize its magnetic domain polarity. High alternating current (AC) electric fields, in particular, create powerful local alternating magnetic fields that rapidly scramble domain alignment.
- Material buildup ("air gap" effect): Accumulated fine iron on the surface acts as a barrier, pushing the active magnetic field further away from incoming material. Because magnetic force decays exponentially with distance, even a few millimetres of buildup severely reduces capture rates.
- Increased process velocity or burden depth: Running material too fast, or in overly thick layers, prevents fine ferrous particles from spending enough time in the peak magnetic field zone to be pulled out of the flow.
Signs an NdFeB Magnet or Separator Needs Replacing
- Drop in gauss rating: Annual or semi-annual gauss testing shows a permanent drop of 10–15% or more from the baseline specification.
- Bulging or "pillow" swelling: The protective stainless steel tube cladding looks warped, swollen, or cracked — a sign of internal oxidation where rust has expanded inside the shell.
- Dead spots along the field: Measuring with a gauss meter reveals localised spots with zero or drastically lower magnetic pull across the grid or tube surface.
- Downstream metal contamination: Ferrous fines or tramp iron start showing up in final product testing or downstream machinery detectors despite the separator being clean.
- Structural casing punctures: Scratches, gouges, or pinhole leaks in the stainless steel jacket expose the internal magnetic circuit to moisture and process fluids.
Regular gauss testing (at least annually) is the most reliable way to catch strength loss before it affects downstream product purity — PML's own range of Gaussmeters and magnetic field meters covers this. If you're seeing any of the signs above, talk to our team about testing or replacing your separator.
