Conveyor Metal Detection Equipment

GJT-F Metal Detector for Belt Conveyors

Corvelan GJT-F metal detectors find unwanted metal in bulk materials moving on belt conveyors before it reaches crushers or other downstream equipment. The current family covers nominal belt widths from 500 to 2000 mm. We select the starting model from belt width, then check material depth, target metal, belt speed and installation conditions before confirming the equipment.

ApplicationBulk-material belt conveyors that need metal detection before a critical downstream step.
DetectsIron, aluminum, stainless steel and alloy metal targets listed in the GJT-F family data.
Model RangeGJT-5F through GJT-20F for nominal belt widths from 500 to 2000 mm.
Send UsBelt width, material depth, speed, target metal, conveyor layout and the required line action.
GJT-F metal detector installed around a bulk-material conveyor belt

Quick Fit

Is the GJT-F right for your conveyor?

We recommend the GJT-F for belt-conveyed bulk material when unwanted metal must be found before the next process step. Belt width starts the model choice; the material, target metal, speed and installation decide whether the setup is suitable.

Good fit

  • Bulk solids moving on a belt conveyor.
  • A clear point exists before a crusher, mill or other critical equipment.
  • The line can use an alarm, belt stop, PLC signal or another response after detection.

We check first

  • Material depth, belt speed and the metal target.
  • Belt clips or splices, vibration and nearby steelwork.
  • Magnets, large motors, VFDs or other possible interference sources.

Another solution may be better

  • The process needs physical metal removal without a separate reject or separation device.
  • The material moves through a wet slurry, gravity pipe or pneumatic line instead of a belt conveyor.
  • The project needs construction or certification that has not been confirmed for the quoted equipment.

Why & Where

Why use GJT-F, and where should it go?

The detector is most useful where finding metal gives the conveyor enough time to react before a critical machine or process step. Corvelan reviews the line action together with the installation point.

Before a crusher or mill

Detect damaging metal before it reaches crushing, grinding or other vulnerable equipment.

After a transfer point

Check the material after loading or transfer steps where contamination may enter the product stream.

Before another critical process

Place the detector where an alarm, belt stop or other action can still happen before the metal reaches the protected equipment.

As part of the control system

Use the relay output for an alarm, belt stop, PLC input, marking device or another defined line response.

Frame metal detector installed on a bulk material conveyor upstream of a crusher

Process-position diagram showing typical detector locations before critical equipment.

Detector vs Magnetic Separator

GJT-F metal detector vs magnetic separator: what is the difference?

A metal detector finds a metal event and sends a signal. A magnetic separator physically captures suitable magnetic metal. They solve different parts of the contamination problem and can be used together.

QuestionGJT-F Metal DetectorMagnetic Separator
Main jobDetect a metal event and send an output signal.Physically capture or separate suitable magnetic metal.
Iron / steelCan be detected when the target and operating conditions are suitable.Suitable magnetic iron or steel can be captured by the correct separator.
Aluminum / other non-magnetic metalCan be detected under suitable conditions.Conventional magnetic separators do not capture non-magnetic aluminum.
What happens after detection?Relay output can be used for an alarm, belt stop, PLC input or another action.The separator performs the physical magnetic removal step.
Can they work together?Yes. Detection can be added where the line also needs to find metal that a magnet may not remove.Yes. Magnetic removal can be used upstream or downstream depending on the process.

Selection point: tell Corvelan whether you need metal detection, magnetic removal, or both. We will review the material, target contaminant and conveyor layout before recommending the equipment path.

Frame metal detector and suspended magnetic separator installed at different positions along a bulk material conveyor

Engineering diagram comparing metal detection and magnetic removal positions on a conveyor line.

Material & Target Metal

What material and metal target should we review?

Current GJT-F technical specifications cover applications in thermal power, cement, building materials, papermaking, mining, food and chemical processing. We still review the actual conveyed material before selecting the detector.

The specifications cover iron, aluminum, stainless steel and alloy metal targets. Detection depends on more than metal type, so send the target size or shape when it matters to your process.

Send these material details when available:

  • Material and physical form
  • Target metal and target size or shape
  • Normal and maximum material depth on the belt
  • Particle size, moisture and bulk density when relevant
GJT-F metal detector on a conveyor handling coarse bulk material

Working Principle

How does a GJT-F conveyor belt metal detector work?

Bulk material passes through the sensing opening. A metal object changes the electromagnetic signal. The electronics evaluate that change and the relay sends a detection signal to the conveyor control system.

01 — Material passesThe conveyor carries material through the sensing zone.
02 — Metal changes the signalA metal object changes the electromagnetic response.
03 — Electronics evaluateThe detector checks and amplifies the change.
04 — Relay sends the outputThe line can use the signal for an alarm, stop or another action.

Model Selection

How does Corvelan select the starting GJT-F model?

Belt width gives us the first model to review. We then check material depth, target metal, belt speed, the installation environment and the action required after detection.

Engineering selection review photo showing a GJT-F metal detector on a bulk material conveyor during installation review

Educational selection flow: belt width is the starting point, not the final model decision.

Nominal belt width (mm)Starting model to reviewWhat Corvelan checks next
500GJT-5FMaterial depth, target metal, normal and maximum belt speed, available space, vibration, belt splice or clips, nearby magnets or motors, and the required alarm / stop / PLC action.
650GJT-6F
800GJT-8F
1000GJT-10F
1200GJT-12F
1400GJT-14F
1600GJT-16F
1800GJT-18F
2000GJT-20F
Do not select by belt width alone. A belt width match does not confirm detection performance or installation suitability.

Model Selection Table

GJT-F models for 500–2000 mm nominal conveyor belt widths

The current GJT-F family covers nine models for nominal belt widths from 500 to 2000 mm. Use the table for family specifications, then confirm the application conditions before treating any sensitivity value as a pass/fail requirement.

ModelBelt width (mm)Power (W)Belt speed (m/s)Family reference sensitivity*Weight (kg)
GJT-5F500≤400.8–2.5φ20 mm iron/aluminum sphere*105
GJT-6F650≤400.8–2.5φ20 mm iron/aluminum sphere*125
GJT-8F800≤500.8–2.5φ20 mm iron/aluminum sphere*160
GJT-10F1000≤500.8–2.5φ20 mm iron/aluminum sphere*190
GJT-12F1200≤500.8–2.5φ20 mm iron/aluminum sphere*255
GJT-14F1400≤600.8–2.5φ20 mm iron/aluminum sphere*290
GJT-16F1600≤600.8–2.5φ20 mm iron/aluminum sphere*350
GJT-18F1800≤650.8–2.5φ20 mm iron/aluminum sphere*430
GJT-20F2000≤700.8–2.5φ20 mm iron/aluminum sphere*480

*Reference sensitivity: the published product family specifications lists a φ20 mm iron/aluminum sphere reference but does not state the controlled test method. We use it as a family selection reference, not as an unconditional minimum-detection guarantee for every material, burden depth or installation.

Family electrical input listed in the supplied data: AC 220 V ±10%, 50 Hz.

Installation Dimensions

Check the GJT-F dimensions before planning the installation

Use A, B, C, D, E, L and L1 from the family drawing to check whether the detector frame and support area fit the available conveyor space. The final layout still depends on the selected model and site clearances.

ModelA (mm)B (mm)C (mm)D (mm)E (mm)L (mm)L1 (mm)
GJT-5F820690250410250740300
GJT-6F1000840250410250890300
GJT-8F120010102504102501090300
GJT-10F140012402504102501320300
GJT-12F163014702504303001550370
GJT-14F183016802504303001740370
GJT-16F205018902504303001950370
GJT-18F228021202504303002180370
GJT-20F250023402504303002400370

Performance & Installation

What can change GJT-F detection or installation performance?

One sensitivity number does not describe the whole application. We check the metal target, material, conveyor and surrounding equipment together.

CheckWhy it mattersWhat to send Corvelan
Target metalType, size, shape and direction affect the detection target.Metal type and the smallest piece that matters.
Material depthChanges the distance between the target and sensing zone.Normal and maximum depth on the belt.
Material conditionConductive, magnetic or highly mineralized material can change the detector response.Material, moisture, particle size and bulk density when relevant.
Belt speedThe family reference is 0.8–2.5 m/s.Normal and maximum speed.
VibrationThe family instruction shows direct frame mounting below 0.5 mm vibration amplitude and a separate fixed support above that reference.Photo, video or measured vibration information if available.
Belt splice / clipsMetal parts in the belt can affect the detection setup.Photo, drawing or splice / clip type.
Nearby equipmentMagnets, large motors, VFDs and heavy steelwork can affect the installation environment.Conveyor layout and the position of nearby equipment.

Family installation references

  • Power: AC 220 V ±10%, 50 Hz.
  • Vibration: below 0.5 mm is the family reference for direct conveyor-frame mounting.
  • Nearby belt-type magnetic separator: the supplied family layout shows more than 10 m as an example arrangement, not a universal rule for every site.
  • Access: leave room for the control enclosure, wiring checks and test pieces.
GJT-F metal detector installed on an industrial belt conveyor

Controls & Response

How can the GJT-F connect to the conveyor control system?

The detector finds metal and sends a control signal; it does not physically remove the metal by itself. The GJT-F family data lists one normally open (NO) and one normally closed (NC) relay contact, plus a 1–10 second delayed relay release. The outputs can connect to an alarm, belt stop, PLC, marking device or another reject / separation device.

Detection Check

How do we check whether the GJT-F can meet your detection target?

A useful target needs more than one sensitivity number. The φ20 mm iron/aluminum sphere value in the family table remains a family reference because the supplied sheet does not give a complete controlled test method.

1 — Target metalDefine the metal type, approximate size, shape and the smallest piece that matters.
2 — Material conditionDefine the conveyed material, material depth and relevant moisture or mineralization.
3 — Conveyor conditionConfirm belt speed, splice or clip type, vibration and the installation arrangement.
4 — Required line actionConfirm whether detection should trigger an alarm, belt stop, PLC input or another action.
5 — Check methodIf a recorded pass/fail check is required, agree on the test piece, position, operating condition and record before order.

Important: the family φ20 mm reference is not published here as an unconditional minimum detection guarantee.

Family Information & Project Check

What is confirmed for the GJT-F family, and what do we confirm for your project?

The current GJT-F published product family specifications and real family installation photos support the product identity, model range, listed electrical/control data, dimensions and installation references used on this page. Detection performance for a specific line still depends on the actual material, target metal and installation condition.

MODEL RANGEGJT-5F to GJT-20F for nominal belt widths from 500 to 2000 mm.
BELT SPEED REFERENCE0.8–2.5 m/s is listed in the current family data.
POWER / OUTPUTAC 220 V ±10%, 50 Hz; one NO and one NC relay contact are listed.
DELAY / INSTALLATION1–10 s relay release; vibration and nearby-magnet references are treated as family installation guidance.
Confirmed from current family information
  • GJT-5F through GJT-20F model range.
  • 500–2000 mm nominal belt-width range.
  • 0.8–2.5 m/s family belt-speed reference.
  • AC 220 V ±10%, 50 Hz input.
  • One normally open (NO) and one normally closed (NC) relay contact.
  • 1–10 second delayed relay release.
  • Below 0.5 mm conveyor-frame vibration as the family reference for direct mounting.
  • More than 10 m from a belt-type magnetic separator in the supplied example layout.
  • φ20 mm iron/aluminum sphere value as a family sensitivity reference, not an unconditional minimum guarantee.
We confirm for each project
  • The smallest metal target that matters to your process.
  • How the conveyed material and material depth affect the required detection check.
  • The exact mounting position, support and surrounding steelwork.
  • Belt splice / clip details, vibration and nearby magnetic or electrical equipment.
  • Alarm, belt-stop, PLC or other required control action.
  • The pass/fail test method if a recorded acceptance check is required.
  • Any special construction, documentation or certification required by the project.
GJT-F metal detector spanning a conveyor carrying bulk material
Real GJT-F family conveyor installation view. No exact submodel or performance result is inferred from the photo alone.
Industrial conveyor installation view of a GJT-F metal detector
Real installation view used to review detector position, access and surrounding conveyor steelwork.
GJT-F frame metal detector integrated with conveyor steelwork
Real GJT-F family installation view showing how the detector frame integrates around the conveyor.

Engineering diagrams illustrate the detection principles, installation positions and key selection factors.

What Happens Next

What happens after you send Corvelan your conveyor details?

We use the submitted information to narrow the model, check the installation conditions and define the remaining inputs required for quotation.

01We review belt width, speed, material depth and available space.
02We review the target metal and the smallest piece that matters to your process.
03We review vibration, nearby equipment, belt splice and the required control action.
04We prepare the model and project information needed for the quote.

FAQ

GJT-F conveyor metal detector questions

What metals can the GJT-F metal detector detect?

Our current GJT-F family data lists iron, aluminum, stainless steel and alloy metals. The smallest metal size the detector can find in real use still depends on metal size, shape and direction, material depth, the conveyed material and installation conditions.

What conveyor belt widths are available?

Our current GJT-F family range covers nominal belt widths from 500 to 2000 mm, from GJT-5F through GJT-20F. We confirm the final model against the actual belt profile, material depth and available installation space.

What does the φ20 mm sensitivity reference mean?

The family table lists a φ20 mm iron/aluminum sphere reference. Because the supplied sheet does not give a complete test method or cover every material condition, we use this value as a selection reference. If the smallest metal size is critical, we check it under the agreed operating condition.

Can the GJT-F be installed near a magnetic separator?

The family layout drawing shows more than 10 m from a belt-type magnetic separator and non-magnetic rollers near the detector as an example arrangement. Send us the actual layout because magnet type, steelwork and electrical interference vary from site to site.

Can it work with metal belt clips or splices?

The family data references a metal belt-clip detection function. We confirm the actual clip or splice design and include it in the detection check for your conveyor.

Does the GJT-F remove the metal after detection?

No. The GJT-F detects the event and provides alarm/relay outputs. Physical removal requires the separate response designed into your line, such as belt stop/manual removal, a reject device or another separation device.

What should I send Corvelan for GJT-F selection?

Start with the material, target metal, throughput and conveyor/installation drawing or condition. If available, also send belt width, speed, burden depth, splice type, vibration, nearby magnetic/electrical equipment, power and the action you want after detection.

What to Send for a Quote

What do we need to select your GJT-F and prepare a quote?

Start with the four items below. Add conveyor and detection details when available so we can check the model and installation with less back-and-forth.

Required to Start

  • Material and physical form
  • Target metal / damaging object
  • Throughput — how much material the conveyor carries per hour
  • Conveyor or installation condition / drawing

Strongly Recommended

  • Belt width and trough profile
  • Normal and maximum belt speed
  • Normal and maximum material depth on the belt
  • Particle size, moisture and bulk density if relevant
  • Belt splice/clip or steel-cord details
  • Vibration and nearby equipment

If You Have a Pass/Fail Target

  • Target metal size, shape and orientation
  • Where the test piece should be placed
  • Required alarm / belt-stop / PLC action
  • Required standards or project documents
  • Any test record you need with the order

Send these details to Corvelan. We will check the GJT-F model range, installation conditions and the control action you need before preparing the quote.

Next Step

Send Your Metal Detection Requirement

Send the material, target metal, throughput and conveyor details. We will review the starting model, installation conditions and the detection requirements needed to complete the quotation.

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