 |
| Quantity: | |||||||||
|---|---|---|---|---|---|---|---|---|---|
Product Description
Every plastic pellet that enters your injection molding machine carries invisible risk. Buried inside what appears to be clean, virgin material can lurk ferrous metal contaminants — a fragment of chipped tool steel, rust scale from a storage silo, a stray screw shaving from a regrind operation. None of them are visible. All of them are destructive.
When a ferrous particle enters the barrel, it becomes an abrasive projectile driven forward by the reciprocating screw at thousands of PSI. It gouges the barrel wall, wears down the screw flight, and scars check rings and non-return valves. It clogs hot runner nozzles. It leaves burn marks, black specks, or pits on molded parts that fail visual inspection or — worse — reach the customer before the defect is discovered. In the worst case, a hard metal fragment bridges across a mold cavity and the mold closes on it, stamping a permanent crater into a $50,000 tool.
These failures are not hypothetical. They are everyday realities in injection molding plants that skip one of the simplest and cheapest protections available: a magnetic separator at the material inlet.
Install a CJ Series Magnetic Frame from Chenxing Machinery between your bin-gate dryer and the injection machine feed throat, and you stop ferrous metal at the last possible point before it enters the barrel. No ferrous particle larger than a few microns passes. No damage to screw, barrel, or mold. And the device that does this costs a fraction of one emergency screw replacement and operates at zero ongoing cost — no electricity, no compressed air, no consumables.
The economics are straightforward. A single screw and barrel replacement for a mid-size injection machine costs 10,000. A mold cavity repair runs 5,000, and the downtime to pull the mold, send it out, and reinstall it is measured in days — not hours — of lost production. The CJ Magnetic Frame costs less than the deductible on most equipment insurance policies, and it works every shift, every day, drawing zero amps.
Three models cover the full range of injection molding machines from 15g to 6300g shot capacity. Select by your machine size and dryer model to ensure complete coverage of the hopper cross-section.
| Model | Fits Injection Molding Machine (g) | Compatible Bin-Gate Dryer | Number of Magnetic Tubes |
|---|---|---|---|
| CJ-1 | 15–500 | STG-U16 ~ STG-U80 | 7 |
| CJ-2 | 500–2500 | STG-U125 ~ STG-U315 | 9 |
| CJ-3 | 2500–6300 | STG-U400 ~ STG-U800 | 11 |
CJ-1: Designed for small-tonnage machines (15–500g shot). Fits standard STG-U16 through STG-U80 bin-gate dryers. Seven magnetic tubes spaced to cover the full hopper cross-section of compact machines. Ideal for precision molding cells producing small medical, electronic connector, or micro-component parts where even a single black speck is unacceptable.
CJ-2: The mid-range workhorse for medium-tonnage machines (500–2500g shot). Pairs with STG-U125 through STG-U315 dryers. Nine magnetic tubes provide increased capture capacity for higher material throughput. Suitable for automotive component, consumer goods, and general industrial injection molding.
CJ-3: Heavy-duty protection for large-tonnage machines (2500–6300g shot). Compatible with STG-U400 through STG-U800 dryers. Eleven magnetic tubes deliver maximum ferrous capture area for high-volume material flow. For large-part molding — pallets, container bins, automotive bumpers, furniture components — where material throughput demands the largest capture surface.
All CJ models mount directly onto the hopper or dryer discharge flange. No adapter plates, no modifications to existing equipment. If you can access the hopper neck, you can install the frame.
The CJ Magnetic Frame operates on one of the oldest and most reliable principles in physics: ferromagnetism.
The frame consists of multiple parallel magnetic tubes arranged in a grid that spans the entire hopper cross-section. Each tube is a high-strength permanent magnet encased in a durable metal sleeve. When installed at the hopper inlet or between the dryer outlet and the feed throat, the frame presents a magnetic field that every pellet must pass through on its way into the barrel.
As plastic pellets flow under gravity through the hopper, they cascade over and between the magnetic tubes. Ferrous particles — iron chips, rust flakes, screw shavings, stray steel fragments — are pulled out of the material stream and held firmly against the tube surfaces. Non-ferrous and clean pellets pass through unimpeded.
There is no power supply. No control panel. No moving parts. No consumable filter media. The permanent magnets maintain their field strength for years of continuous service. The only maintenance required is periodic removal of the accumulated ferrous debris — a task that takes minutes and requires no tools beyond a rag or brush.
This is what separates the CJ Magnetic Frame from powered magnetic separators, metal detectors with reject gates, or X-ray inspection systems: those technologies have their place downstream or for finished-product inspection, but they cost tens of thousands of dollars to purchase, require ongoing calibration and maintenance, and introduce their own points of failure. The CJ Magnetic Frame costs a small one-time investment and never needs calibration, never trips a false reject, and never causes a false pass. It simply works.
Feature: Multiple parallel magnetic tubes arranged to span the entire diameter of the hopper or dryer outlet. Seven tubes on CJ-1, nine on CJ-2, eleven on CJ-3 — spacing is engineered so that no pellet path bypasses the magnetic field.
Benefit: Unlike single-bar or single-plate hopper magnets that leave gaps around the edges, the CJ frame ensures every gram of material is scanned. A ferrous particle cannot "slip through the side" of the field.
Feature: Each CJ model is keyed to a specific range of injection machine shot capacities and STG-U series bin-gate dryer models. The frame dimensions, tube count, and mounting flange pattern are pre-configured for these machines.
Benefit: No guesswork, no field modifications, no return shipments because "it didn't fit." Order the model that matches your machine and dryer, and installation is a direct bolt-on. This also means the magnetic field is correctly positioned at the optimal height in the material column for maximum capture efficiency.
Feature: High-strength permanent magnets inside each tube. No electromagnet coils, no power supply, no wiring.
Benefit: Zero electricity cost. Zero risk of a power outage disabling your metal protection. The magnets retain their field strength for the operational life of the machine — typically a decade or more in normal service. If you run 24 hours a day for 10 years, your operating cost for magnetic separation is exactly zero.
Feature: Metal frame and durable metal sleeves encasing each magnetic tube. Withstands the vibration, temperature cycling, and incidental contact common in injection molding environments.
Benefit: Unlike plastic-housed magnets that crack under mechanical stress or temperature exposure, the CJ frame handles the ambient heat of a dryer outlet (typically 80–120°C for most materials) and the physical demands of daily production without degradation.
Feature: Bolt-on flange design that mates to standard hopper and dryer flanges. Removal requires loosening a few bolts — no disassembly of the material handling system.
Benefit: Cleaning frequency is the only operational consideration, and the CJ frame is designed to make that as fast as possible. Remove, wipe the tubes clean of captured ferrous debris, reinstall. Typical cleaning cycle: 5 minutes. This encourages regular maintenance instead of avoidance.
Feature: Positioned as the last line of defense before material enters the barrel, the CJ frame captures ferrous contaminants that would otherwise reach the screw, barrel, check ring, hot runner manifold, nozzle tip, and mold cavity.
Benefit: One 3,000 screw, a 50,000 mold, and an injection machine worth 500,000. The protection-to-cost ratio is among the highest of any auxiliary equipment in a molding plant.
Feature: The CJ Magnetic Frame is material-agnostic. It works with PP, PE, ABS, PS, PA, PC, PET, PVC, POM, TPE, and any other pelletized thermoplastic — as well as regrind and masterbatch.
Benefit: One frame serves all materials. No adjustments, no settings to change, no parameters to reconfigure when switching materials or colors.
The CJ Magnetic Frame installs at the hopper inlet — typically between the outlet flange of the bin-gate dryer and the feed throat of the injection molding machine. It can also be mounted directly on a machine hopper if no dryer is in use.
Position: Place the frame on the hopper or dryer flange, ensuring the magnetic tubes face downward into the material flow path.
Bolt: Secure with the provided fasteners through the pre-drilled flange holes.
Verify: Confirm the frame sits flush and does not obstruct the hopper throat or interfere with the material gate mechanism.
No welding, no drilling, no modifications to existing equipment. The frame uses the same bolt pattern as standard hopper-to-dryer flange connections. Typical installation time is under 15 minutes.
The only maintenance required is periodic cleaning to remove accumulated ferrous debris from the magnetic tube surfaces.
Recommended cleaning frequency: Every 40–80 operating hours, or at each material or color change. For operations processing high-regrind-content material or post-consumer recycled feedstock, check weekly and increase frequency if accumulation is rapid.
Cleaning procedure: Remove the frame from the hopper (loosen bolts, lift off). Wipe each magnetic tube with a dry cloth or brush to remove captured particles. For heavy accumulation, use a non-magnetic scraper. Reinstall. Total downtime: 5 minutes.
Inspection: During each cleaning, visually inspect tube sleeves for wear or damage. Sleeves are replaceable if needed — contact Chenxing Machinery for spare parts.
No lubrication points. No filter replacements. No calibration. One of the lowest-maintenance pieces of equipment on your molding floor.
A ferrous metal particle entering the injection barrel travels forward with the melt at injection pressure — often 1,000–2,000 bar. If it reaches the mold cavity during injection, the mold closes on it. Tool steel against tool steel under clamping force results in a permanent indentation, crack, or crater in the cavity surface. Mold repair costs 5,000 per cavity, and the mold is out of production for days. The CJ Magnetic Frame captures that particle at the hopper inlet, before it ever reaches the barrel. For roughly the price of one mold polishing service call, you prevent an unlimited number of potential mold strikes.
Every 40–80 operating hours under normal conditions, or at every material/color change. If you process high percentages of regrind or post-consumer recycled material — which typically carry higher ferrous contamination — inspect weekly and increase cleaning frequency as needed. The visual indicator is clear: when you can see a layer of black ferrous powder or particles coating the tubes, it is time to clean. A saturated magnet loses capture efficiency, so regular cleaning directly protects your equipment.
Permanent magnets do degrade, but the rate is extremely slow. Modern rare-earth and ferrite permanent magnets used in industrial magnetic separators typically retain over 95% of their original field strength after 10 years of continuous service. The CJ frame's magnets are selected for stability under the operating temperature range of standard injection molding environments (up to approximately 120°C ambient at the hopper). The limiting factor is usually mechanical — sleeve wear from abrasive materials — rather than magnetic decay. Sleeves are replaceable; the magnets themselves are effectively lifetime components.
Match your machine's shot capacity (in grams) and bin-gate dryer model to the table below:
15–500g machine with STG-U16 ~ STG-U80 dryer → CJ-1 (7 tubes)
500–2500g machine with STG-U125 ~ STG-U315 dryer → CJ-2 (9 tubes)
2500–6300g machine with STG-U400 ~ STG-U800 dryer → CJ-3 (11 tubes)
If your dryer model falls outside the STG-U series, provide your hopper flange dimensions to Nicole at ceo@cxsljx.com and we will confirm compatibility or recommend an alternative mounting solution.
Yes. The CJ Magnetic Frame uses a standard bolt-on flange that mates with the existing hopper or dryer outlet flange. No drilling, no welding, no cutting. If your hopper has a standard bolted flange connection to the dryer or feed throat, installation is a direct fit. For machines with non-standard or proprietary flange patterns, Chenxing Machinery can supply adapter plates — contact us with your flange dimensions.
None. The CJ Magnetic Frame uses permanent magnets — no electricity, no compressed air, no consumables, no filter elements. The purchase price is the total cost of ownership for years of service, apart from occasional sleeve replacement if wear occurs. Compare this to powered electromagnetic separators, which consume electricity continuously and require periodic coil replacement, or to metal-detector-plus-reject systems that need calibration, compressed air supply, and maintenance of pneumatic valves and gates. For the task of protecting the injection machine from ferrous contamination at the hopper, the CJ Magnetic Frame is both the simplest and the most cost-effective solution.
No. The magnetic field holds captured ferrous particles firmly against the tube surfaces. Gravity and material flow are not strong enough to dislodge them. Even at maximum throughput rates, the captured debris remains in place until the operator physically wipes it away during the next cleaning cycle. This is a key advantage over grate-style magnets where material flow can occasionally wash particles off the magnet faces — the CJ frame's tube geometry creates a shielded capture zone that the material stream passes over without scrubbing.
Adding magnetic protection to your injection molding line is one of the fastest, lowest-cost ways to reduce unplanned downtime and protect capital equipment. Here is how to get started:
Step 1 — Identify Your Machine: Note your injection machine shot capacity (grams) and bin-gate dryer model (STG-U series label on the dryer body).
Step 2 — Select Your CJ Model: Use the specification table above to match your machine to the correct CJ frame. One frame per machine.
Step 3 — Contact Nicole for a Quote: Reach out with your machine specifications and quantity required. We will confirm model compatibility, provide pricing, and advise on lead time.
Step 4 — Install and Forget: Bolt the frame onto your hopper or dryer flange in under 15 minutes. Set a recurring cleaning reminder for every 40–80 hours. Your screw, barrel, and mold are now protected — at zero ongoing cost.
For integrated production lines that require upstream material preparation beyond magnetic separation, Chenxing Machinery also supplies high-speed mixers, plastic crushers, and complete PVC pelletizing lines — ask Nicole about system-level solutions.
Contact Chenxing Machinery Today:
Contact Person: Nicole
Phone / WhatsApp: +8615951187228
Email: ceo@cxsljx.com
Company: Zhangjiagang Chenxing Machinery Co., Ltd.
Website: www.chenxingmachinery.com
