Ceramic foam filters are the fastest way to cut casting defects and boost yield in aluminum foundries. For Indian buyers, selecting the right pore size and material delivers measurable reductions in surface defects and scrap. For high-value components that demand consistent purity, adtech’s alumina and SiC foam filters offer industrial-grade performance at factory pricing, and many Indian foundries combine local supply with imported ADTECH filters to meet tight quality targets.
Why this topic matters to Indian foundries
Molten metal filtration is no longer optional. With rising quality standards for automotive, foil, and aerospace aluminum, foam ceramic filters reduce oxides, entrained dross, and turbulent flow defects. The right filter selection reduces rework, shortens machining allowance, and raises first-pass yield. Independent studies show optimized ceramic filtration improves mechanical properties and lowers scrap in alloy castings.
Who adtech is, in one line
adtech Metallurgical Materials Co., Ltd produces alumina and silicon-carbide ceramic foam filters plus filtration accessories for molten aluminum, and maintains an active sales presence for Indian buyers.
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Industrial-grade PPI control (10–60 PPI) suited for sand casting, gravity die, permanent mold.
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Supply chain options: local stockists plus direct factory export pricing.
Adtech ceramic foam filters product advantages
| Feature | What it means for a foundry | Practical benefit |
|---|---|---|
| Material options: Alumina, SiC, Zirconia | Filters can be matched to alloy chemistry and melt temperature | Lower chemical reaction risk, longer filter life |
| Controlled pore sizes (PPI range) | Match filtration depth to casting type | Better capture of oxide films, fewer surface faults |
| High porosity, high thermal shock resistance | Filter tolerates sudden temperature swings | Fewer filter failures during pour |
| Factory direct pricing for bulk orders | Lower per-unit cost for frequent users | Reduced cost per casting, improved margin |
| Standardized sizing and custom shapes | Fits existing filter boxes or bespoke rigs | Eases retrofit and reduces engineering time |
Table source: adtech product pages and company literature.
Five Indian ceramic foam filter manufacturers
Below are five Indian companies that manufacture or supply ceramic foam filters. Each entry includes location and a short note on capabilities.
| Company | Location | Short capability note |
|---|---|---|
| Patronage Filtex India Pvt. Ltd. | Kolhapur, Maharashtra | Claims state-of-the-art manufacturing for alumina, SiC, zirconia foam filters. |
| Techno Crat Foundrychem Pvt. Ltd. | Pune, Maharashtra | Foundry-chemical and filter supplier listed on national B2B platforms. |
| S S Khardekar India Pvt. Ltd. | Pune area (operations nationwide) | Established foundry product maker; supplies ceramic filters under trade partnerships. |
| Jagannath Company | Delhi | Foundry supplier and exporter that lists ceramic foam filters among product lines. |
| Imperial World Trade / Protech Industries | Rajkot / Kolhapur | Large trading houses and manufacturers supplying ceramic foam filters across India. |
These vendors appear in Indian B2B directories and trade listings; buyers often use them for local stock or small-batch orders.
How Indian-made filters compare with imports (table)
| Dimension | Strength of India-made filters | Typical limitation compared with imports |
|---|---|---|
| Lead time | Shorter domestic delivery for small orders | Larger production runs need long lead time if custom |
| Price (small volume) | Competitive for small batches | Per-unit price may be higher than Chinese factory direct for container loads |
| Quality consistency | Many firms produce good parts for general casting | High-precision PPI control and advanced QA more common in specialized exporters |
| Technical support | Local agents can visit plant rapidly | Some exporters provide deeper filtration engineering support |
| Availability of advanced materials | Vendor-dependent | Exporters often stock advanced SiC/ZrO2 grades in larger volumes |
Factors that determine ceramic foam filter price (table)
| Factor | Why it affects price |
|---|---|
| Material type (Alumina, SiC, Zirconia) | Raw material costs vary widely |
| Pore size (PPI) and density | Tight, high-PPI filters need finer raw materials and tighter process control |
| Dimensions and custom shapes | Custom sizes need tooling and lower-volume runs |
| Batch volume | Higher volume yields lower per-unit cost |
| Finish and quality control | Extra inspection and certification add cost |
| Shipping, packaging, customs | International freight and duties can add significantly |
| Local taxes and duties | GST and local levies alter landed cost in India |
Procurement checklist (short table + bullets)
| What to verify | Minimum acceptance criteria |
|---|---|
| Material certificate | Mill test certificate showing composition |
| PPI rating | Manufacturer PPI tolerance ± specified value |
| Thermal shock rating | Test data or certificate |
| Dimensions | Fit check drawing and sample approval |
| Packaging | Moisture-proof, labeled boxes for traceability |
| Lead time | Confirm production and shipping schedule |
Practical procurement bullets:
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Request a sample and run a trial pour before committing to a long-term agreement.
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Negotiate an acceptance test protocol that measures inclusion capture and pressure drop.
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Insist on traceable labeling for each batch to enable root-cause work if defects recur.
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For imported filters, plan customs HS codes and duties; for bulk import, unit landed cost often beats local per-piece price.
Why many Indian foundries use adtech filters
Several Indian foundries purchase adtech filters from China for container shipments when they need predictable PPI control and factory pricing at scale. Public manufacturer pages and trade posts indicate adtech exports to Indian clients and list Indian buyers of adtech metallic filtration products. Combining local suppliers for urgent small orders and adtech imports for bulk orders is a common cost-quality tradeoff in India.
2024 India case study (one foundry)
Project overview (company anonymized for confidentiality in public posts)
Client: a Tier-1 alloy wheel caster in Chennai. Timeline: February 2024. Problem: high rejection rate due to oxide films and hard spots while using a generic local 30 PPI filter.
Intervention
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Replaced generic filter with adtech 30 PPI SiC filter tuned for gravity die process.
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Adjusted pouring gating and filter box placement per supplier recommendations.
Outcome (before / after)
| Metric | Before (generic local filter) | After (adtech filter + process tune) |
|---|---|---|
| Rejection rate | 6.5% | 1.8% |
| Surface defects per 1,000 casts | 40 | 9 |
| Scrap weight reduction | High | ~72% reduction in defect rework |
| Yield improvement | Baseline | Net positive margin increase reported |
The client performed metallographic checks and confirmed fewer oxide inclusions in test coupons. The result demonstrates how consistent filter PPI and correct placement yield fast returns on filter investment.
Technical selection: PPI, material, shape
Choosing PPI
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10–20 PPI: use for sand casting where flow must be high.
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30–40 PPI: common for gravity die and many general-purpose runs.
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50–60 PPI: reserved for foil, plating baseboard, and ultra-clean applications.
Pick the coarsest PPI that still meets defect targets. Coarser filters let metal pass faster; finer filters trap smaller inclusions but increase back-pressure and can slow filling.
Material selection
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Alumina: economical and good thermal stability for many aluminum alloys.
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Silicon carbide (SiC): better wear resistance and higher temperature tolerance, preferred for alloy/foil work.
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Zirconia: used when alloy chemistry or critical applications demand the best chemical inertness.
Shape and mounting
Square and round plates fit standard boxes. Custom shaped filters reduce dead volume for small pours and improve flow uniformity.
Quality assurance and test methods
Key tests to require from the vendor:
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Bulk density and open porosity measurement.
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Pore size distribution and PPI certification.
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Thermal shock cycles data or certificate.
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Filtration efficiency tests on standard contamination coupons.
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Traceable batch numbering and packaging photo proof.
Independent lab testing on sacrificial samples is recommended before wide adoption. Filtration research indicates real improvements in mechanical performance when filters meet design parameters.
Procurement negotiation tips
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Ask for a small sample shipment for lab validation before a full order.
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For bulk import, negotiate FOB factory price and choose freight term that the buyer controls.
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Include acceptance criteria in contract that tie payment to passing weld or inclusion tests.
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If the seller claims superior performance, request test data and client references in India.
Indian local strengths and weaknesses
Strengths
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Faster local re-supply for urgent small orders.
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Easier vendor visits and quicker technical support.
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Lower logistics paperwork for small batches.
Weaknesses
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For container-volume orders, local per-piece price may be higher.
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Advanced high-PPI control and consistent QA processes might be less standardized across all local vendors.
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Some Indian buyers continue to import Chinese filters for specialized requirements. Evidence of import activity is visible in customs and trade records.
Common pitfalls foundries make when introducing ceramic foam filters
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Selecting PPI purely on price rather than on casting type.
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Installing filters with gaps that allow metal to bypass filtration.
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Overlooking packaging and moisture protection during local transport.
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Failing to pre-wet or condition filters when required by manufacturer practice.
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Skipping metallurgical checks after trial pours.
FAQs
1: What pore size should I choose for gravity die casting?
Use 30–40 PPI for a balance between flow and filtration. If product requires ultra-clean surface, test 50 PPI in pilot pours.
2: Can ceramic foam filters be reused?
No. Filters trap inclusions and the internal structure fills. Reuse risks reintroducing contaminants.
3: Why do some filters produce higher back pressure?
Higher PPI and denser filters reduce permeability and raise pressure. Design gating to compensate.
4: Are India-made filters compatible with all aluminum alloys?
Most are compatible, but confirm chemical composition and thermal tolerance for specialty alloys.
5: How should filters be stored on site?
Keep in dry, dust-free, temperature-stable storage in sealed boxes. Moisture degrades binders.
6: Do I need a custom filter box for different sizes?
Standard boxes cover many sizes; for small-volume or thin-wall parts, custom boxes can reduce metal waste.
7: How fast will I see ROI from better filters?
ROI can occur within weeks if scrap reduction and yield gains are significant. Perform a controlled trial to calculate precise payback.
8: Is a Chinese factory direct order cheaper?
For full-container volumes, factory direct pricing often reduces unit cost. Factor in duties and lead time.
9: What documentation should a supplier provide?
Material certificates, PPI verification, batch numbers, and test reports for porosity and thermal shock.
10: Which is better, alumina or SiC?
Choose alumina for economy and general work. Choose SiC when higher temperature tolerance or abrasion resistance is required.
Quick decision checklist for buyers
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Define casting type and quality target.
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Choose candidate PPI range.
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Order samples from both a local vendor and adtech for A/B testing.
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Run metallographic and inclusion-count comparison on test pours.
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Evaluate total landed cost including duties, freight, and local taxes.
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Decide on stock strategy: local emergency stock plus periodic import for volume.