Every January our sales engineers read back through the RFQs that landed in the NAVI Titanium inbox. Enquiries are the cheapest market research a manufacturer can buy: a buyer writes when a filter in the line has stopped behaving, or when a new project forces them to specify something they have never purchased before. Read two hundred in one sitting and patterns appear that no single order shows.
Three framed 2025 for us. Polymer and fibre media kept losing ground in hot, oxidising duties. Requests for titanium grew faster than any other alloy, driven by electrolysis and battery-material work. And the tone shifted: fewer people asked what a sintered filter is, far more asked how to prove one works before releasing budget. Below are the six questions we fielded most often, answered as we answer them.
What buyers asked us in 2025
|
|
Question |
Share |
What the buyer is really worried about |
|
1 |
Powder, mesh or fibre felt - which structure? |
28% |
Rebuilding the housing after a wrong pick |
|
2 |
Same micron rating, different results - why? |
19% |
Rejection at incoming inspection |
|
3 |
How many cleaning cycles before replacement? |
17% |
Spare budget and disposal cost |
|
4 |
What pushes lead time past six weeks? |
15% |
Project milestone dates |
|
5 |
Will porous parts arrive dry, intact and oil-free? |
12% |
Transit damage and contamination claims |
|
6 |
Is metal still the right long-term bet? |
9% |
Technology route risk |
*Internal tally of 212 written enquiries received Jan–Dec 2025. Indicative only.
1. "Powder, mesh or fibre felt - which one do I actually need?"
This sits behind most failed trials. All three are "sintered metal", but they filter differently and fail differently.
Sintered Powder
Irregular grains bonded grain to grain, 0.5–100 µm, 30–45% porosity. Depth filtration, thick walls, easy to weld into an assembly. Strongest where the contaminant is soft or deformable.
Weak spot: once blinded inside the wall, it recovers slowly.
Sintered Mesh
Five woven wire layers diffusion-bonded into one sheet, 1–300 µm. Surface filtration, low clean pressure drop, high mechanical strength. The default for backwashing and pleated high-area cartridges.
Weak spot: hard, sharp particles wedge in the weave.
Sintered Felt
Random metal fibres, 3–80 µm, porosity to 80%. Highest dirt-holding capacity and best permeability per unit thickness. Favoured in polymer melt and hot-gas duties.
Weak spot: cost, and it needs rigid support under high differential pressure.
2. "We ordered 10 µm before and it behaved like 40 µm."
Because "10 µm" means nothing on its own. A rating without a test method is a marketing number - specify the method on your drawing.
|
Test |
Standard |
What it tells you |
When to demand it |
|
Bubble point |
ASTM F316 / ISO 2942 |
Largest pore opening, integrity check |
Every element, incoming inspection |
|
β-ratio (multi-pass) |
ISO 16889 |
Real capture efficiency under continuous flow |
Hydraulic and lube circuits |
|
Permeability |
ISO 4003 |
Flow per unit area at a given ΔP |
Sizing a new vessel |
|
Pressure cycle / burst |
In-house |
Margin before collapse |
Pulse-jet and backwash systems |
Two rules follow. State the fluid and temperature you test at - a gas bubble point and a liquid bubble point are not interchangeable. And ask for the certificate carrying the part number, not a generic datasheet.
3. "Can it be cleaned, and how many times?"
Usually yes; the honest answer is that it depends on what blinded it. Here is how the four common methods compare in the field.
01
Backwash or pulse
Recovers 70–90% of original permeability where the contaminant sits as a surface cake. Cheapest option, but needs ΔP headroom in the design.
02
Ultrasonic with solvent
The practical answer for depth-blinded powder elements. Excellent recovery, though not for thin-wall or long unsupported tubes.
03
Chemical soak
Citric or nitric for stainless, alkaline for organic foulants. Never hydrochloric or any chloride-bearing solution on 316L; pitting follows within weeks.
04
Thermal burn-off
Vacuum or controlled-atmosphere treatment for polymer residue. Not for bronze, nor for anything with a plated or brazed joint.
A well-specified 316L element survives 30–80 cleaning cycles. We log recovery per customer so replacement is decided by data, not guesswork.
4. "Why is one quote 4 weeks and the next one 11?"
Because the variables sit in different places. This is the breakdown we walk through when a buyer asks for a cheaper or faster option.
|
Driver |
Price effect |
Lead time |
How to keep it down |
|
Alloy grade (316L → C276, Ti, Inconel) |
×2 to ×6 |
+3 to +8 weeks for mill stock |
Confirm the real corrosion environment |
|
New tooling for a non-standard shape |
One-off tooling fee |
+2 to +3 weeks |
Reuse an existing die or adjust the housing |
|
Absolute vs nominal rating |
+10 to +25% |
Extra test days |
Specify absolute only where it matters |
|
Documentation (EN 10204 3.1, COA, bubble-point report) |
Small |
+3 to +5 days |
Agree the list at order stage |
|
Batch quantity and furnace nesting |
−15 to −30% at volume |
Consolidated runs |
Bundle annual demand into one release |
5. "How do porous parts survive a sea freight?"
Better than buyers expect, provided packing is treated as part of the product. Porous bodies hold moisture, and moisture plus salt air plus a 40-day container is how a good element arrives with rust bloom.
Dry and degrease - ultrasonic clean, deionised rinse, oven dry; oil-free gloves from here on.
Bubble-point record - every element gets a serialised test value before packing.
Seal - vacuum bag with desiccant and a humidity indicator card.
Cradle - foam or moulded pulp supports; thin-wall tubes never touch the crate wall.
Case - ISPM-15 treated timber for export, "do not weld or machine on site" on the lid.
Arrival check - visual, dimensional, weight and a repeat bubble point within 48 hours.
6. "Where is the market going - is metal still the right bet?"
Electrolysis is pulling titanium forward.
Porous transport layers and gas-diffusion structures in PEM and alkaline stacks are our fastest-growing enquiry line. Grade 2 titanium sinters well, conducts, and survives the anodic environment - buyers who once asked only for 316L now ask for Ti.
PFAS scrutiny is quietly rewriting media specs.
Where a PTFE or PVDF membrane was the default five years ago, procurement now asks for a PFAS-free alternative. A sintered metal element answers that in one sentence.
High-purity is raising the documentation bar.
Battery cathode and semiconductor wet chemistry customers accept nothing less than full traceability, passivation records and cleanroom packing. The metal is the easy part; the paperwork decides who reaches the approved vendor list.
What this means for the next project
The market is not asking for a cheaper disposable anymore. It is asking for a filter that can be validated, cleaned, documented and kept in service through a full audit cycle - a different purchasing decision, and one that rewards buyers who specify the test method before the price.
NAVI Titanium supplies sintered powder, mesh laminate and fibre felt elements in stainless steel, titanium, Hastelloy, Inconel, Monel, nickel and bronze, as cartridges, discs, tubes, plates and welded assemblies built to your STEP file. Send the fluid, temperature, differential pressure and target rating; our engineers return a structure recommendation, a rated drawing and a realistic lead time. Samples ship for trials before any production release.
