Certified Four-Bag Filter Housings

What this case study is, and is not. This is a documented supply case — what was specified, what was built, and what documentation came with it, all traceable to the manufacturer’s certificate and hydro-test report. We have not published operating results because we do not hold Flexiparts’ process data, and we do not publish numbers we cannot evidence.

The requirement

Three rapid-opening multi-bag filter housings for an Australian industrial installation, specified for frequent bag change-out with the documentation to satisfy a pressure-equipment review.

What was supplied

Item	Specification
Description	Rapid-opening four-bag filter housing
Quantity	3 units
Design pressure	0.8 MPa
Design temperature	80 °C
Filter area	2 m² across 4 bags
Overall size	878 × 766 × 1300 mm
Shell material	SS304, ø508 mm
Welding & connecting material	SUS304
Connections	DN50 PN16 PL RF B, HG20592 / 304
Sealing material	Fluoro rubber (Viton)
Surface treatment	Inner and outer mirror polishing
Manufactured to	JB4735-1997
Batch / completion	202410017 · 9 December 2024

The testing

Each vessel was hydrostatically tested before despatch, to a procedure written against the German AD pressure-vessel rules (chapter 9, section 2.1):

Test pressure 1 MPa — above the 0.8 MPa design pressure
Hold time 30 minutes
Chamber volume 200 L
Result passed hydro-test and leak test, no leakage recorded
Certified 10 December 2024, responsible engineer named on the certificate

The documentation went with the vessels

Product certificate stating every parameter in the table above, plus the hydro-test report showing test pressure, hold time and result. That is what a pressure-equipment review asks for, and supplying it after the fact is far harder than specifying it before manufacture.

View the certificate & hydro-test report

Why the quick-open cover mattered here

The unit was specified as rapid-opening rather than bolted. On a housing changed frequently, the cover mechanism is the difference between a two-minute task and a twenty-minute one — and a bolted cover retensioned unevenly by a rushed operator is the most common cause of seal failure on this equipment.

What we would ask for next time. Where the installation is subject to Australian pressure-equipment registration or third-party inspection, that requirement is best raised at enquiry stage — documentation specified before manufacture costs nothing, and retrofitting it afterwards is expensive or impossible.

Specify the same thing

The vessel supplied here is a four-bag housing in the quick-open family. See the four-bag specification, the rest of the quick-open range, or send us your duty for a quote.

FAQ

Questions about this process

What was supplied?

Three rapid-opening four-bag filter housings in SS304, mirror polished inside and out, Viton sealed, DN50 PN16 connections, 0.8 MPa design pressure, 80 degrees C design temperature, 2 square metres of filter area across four bags.

How were they tested?

Each vessel was hydro-tested to 1 MPa, above the 0.8 MPa design pressure, held for 30 minutes with no leakage, to a procedure written against the German AD pressure-vessel rules. The certificate names the responsible engineer.

Are there operating results?

No, and none are published. Misonics does not hold the customer's process data and does not publish numbers it cannot evidence. This is a documented supply case.

Three certified vessels,
documented before despatch.