Mainline Compressed Air Filter CJ-030 C

1. Purpose and Operating Principle

The Grade C filter (polymer pre-filtration cartridge) is the first, coarsest stage of compressed air preparation in the CJ line. It reduces residual oil content in the stream to ≤3 ppm and prepares the air for further, finer filtration (stages T, A, X, H — see “Cartridge Compatibility” below). Grade C itself is not rated by the manufacturer for the micron size of particles retained — the technical documentation only states its residual oil figure and initial pressure drop.

2. Technical Specifications

3. Decoding the CJ-030 C Code

• CJ — mainline filter series (up to 1.6 MPa).
• 030 — body size (rated flow 3.5 m³/min).
• C — filtration grade (pre-filtration, polymer cartridge).

4. Design Features

1. Aluminum alloy body of high strength and hardness, with electrophoretic coating inside and out — corrosion resistance when operating with condensate.
2. Stainless steel cartridge frame with a diamond-pattern mesh — large airflow surface area and low resistance.
3. Drain valve with O-ring seal — leak-tight condensate drainage without PTFE tape, fast and convenient installation.
4. Modular CJ series design — the filter belongs to a line of body-compatible sizes (CJ-005…CJ-150, CJX-200…CJX-400), simplifying selection by flow rate.

5. Installation Recommendations

1. Mounting orientation. Install the filter vertically, with the condensate drain port facing down — for proper discharge of contaminants.
2. Selection by flow rate. The rated flow of the CJ-030 C is 3.5 m³/min (123.6 CFM). At flows close to the maximum, account for the inlet-pressure correction factor (see the manufacturer’s “Pressure Correction Factor” table): below roughly 6–7 bar, actual throughput decreases.
3. Threaded connection. G 1-1/2″ thread — use the drain valve’s standard sealing elements; no additional PTFE tape is required.
4. Multi-stage filtration. For systems requiring higher air purity (painting, food production, precision pneumatic automation), install additional stages with FJ-030 T/A/X/H cartridges after the CJ-030 C, either in the same housing or in separate housings of the same size.

6. Cartridge Compatibility (within the FJ line)

The 030-size housing in the CJ series also accepts finer-grade cartridges from the same line:

• FJ-030 C — pre-filtration, residual oil ≤3 ppm (standard cartridge).
• FJ-030 T — fine coalescing filter, residual oil ≤1 ppm, particles ≤100,000/m³ in the 0.5–1 µm range.
• FJ-030 A — ultra-fine coalescing filter, residual oil ≤0.1 ppm.
• FJ-030 X — high-efficiency oil removal, ≤0.003 ppm, particles ≤10,000/m³ in the 0.5–1 µm range.
• FJ-030 H — activated carbon filter, ≤0.003 ppm, additional removal of oil vapor and odors.

ℹ️ The figures for the T/A/X/H cartridges are taken from the manufacturer’s general “Filtration accuracy of fj filter element” table (applicable to the whole CJ line) and do not refer to the CJ-030 C itself, which ships with a Grade C cartridge.

7. Common Mistakes

• Using the Grade C filter as the only filtration stage where residual oil content below 1 ppm is required — Grade C is designed only for coarse pre-filtration.
• Mounting in a non-vertical position — impairs condensate drainage through the drain valve.
• Using PTFE tape on the drain valve — not required and not provided for by the design; use the standard O-ring seal.
• Ignoring the pressure correction factor — at reduced inlet pressure, the filter’s actual throughput drops (see the manufacturer’s table).

8. Applications

• Compressed air mainlines of industrial facilities — the first stage of air preparation.
• Air preparation ahead of fine/ultra-fine filtration — precedes installation of T, A, X, H cartridges in painting, food production, and precision pneumatic automation systems.
• General industrial pneumatic equipment — protects pneumatic tools and actuators from large contaminants and excess oil.

9. Expert Opinion

Vitalii Boluchevski, lead engineer at Acvatron SRL (18 years of experience): “The CJ-030 C filter is the workhorse of the first air-preparation stage: it doesn’t make the air perfectly clean on its own, but without it the more expensive fine cartridges further down the line clog and fail quickly. Always put it first in the chain.”

10. FAQ

1. What filtration grade does the CJ-030 C have? Grade C — preliminary (coarse) filtration on a polymer cartridge, residual oil content ≤3 ppm.

2. Can the CJ-030 C be used as the only filter in a system? Yes, if air purity requirements are modest (e.g., general industrial pneumatic tools). For painting, food production, or precision pneumatic automation, an additional fine-filtration stage is needed after it (T/A/X/H cartridges).

3. What thread does the filter have? G 1-1/2″.

4. Is PTFE tape needed for installation? No — the drain valve is fitted with an O-ring seal, so no additional sealing is required.

5. What flow rate does the CJ-030 C handle? The rated flow is 3.5 m³/min (123.6 CFM) at a pressure of roughly 7 bar and above; at lower inlet pressure, actual throughput decreases according to the manufacturer’s correction factor.