The DES-CASE DC-ND series Non-Desiccant Breathers are designed for applications where desiccant filtration is unnecessary — specifically low-humidity environments and systems using water-based fluids. Two models cover a wide range of reservoir sizes: the DC-ND-2 for smaller systems and the DC-ND-35 for large-scale industrial reservoirs.
What Are DES-CASE Non-Desiccant Breathers and When Should You Use Them?
DES-CASE Non-Desiccant Breathers prevent particulate contamination without desiccant media. They are the correct choice when moisture absorption is not a concern — such as low-humidity plant environments, oil-misting applications, high-dust environments, or systems running water-based fluids where a desiccant breather could absorb the working fluid itself.
Typical industries served include storage, manufacturing, and automotive. Typical applications include water-based fluid systems, oil misting, low-humidity environments, and high-dust conditions where particulate ingression is the primary contamination threat.
How Does the ePTFE Filter Media Work in DES-CASE DC-ND Breathers?
Both DC-ND models use ePTFE (expanded polytetrafluoroethylene) filter media rated at 0.3 µm absolute. This submicron efficiency stops fine airborne particulates before they enter reservoir headspace. The ePTFE construction also contributes to broad chemical compatibility — the DC-ND series is compatible with all mineral oils, most synthetic oils, and diesel fuels. For other fluids, Des-Case technical support should be consulted.
The housings are built from Nylon 6/6 with 33% glass fill, providing structural rigidity across the full operating temperature range of -40°F to 300°F (-40°C to 149°C). The DC-ND-35 housing also incorporates Plastisol and PTFE components for its larger-format assembly.
What Are the Airflow and Flow Rate Specs for DC-ND-2 vs DC-ND-35?
Airflow and reservoir sizing capacity differ significantly between the two models at a differential pressure of 1 psi (0.07 bar):
- DC-ND-2: Max airflow 0.67 cfm (19 L/min); max reservoir fluid flow 5 gpm (19 L/min)
- DC-ND-35: Max airflow 40 cfm (1,132 L/min); max reservoir fluid flow 300 gpm (1,132 L/min)
For gearbox, pump, and storage tank reservoirs, the DC-ND-2 is sized for systems up to 15 gallons (57 L). The DC-ND-35 sizing should be determined per flow rate for larger applications. The same 15-gallon guideline applies to hydraulic and central lube reservoirs for the DC-ND-2. Des-Case notes that humidity level, frequency of airflow, ambient temperatures, and chemical compatibility must all be considered when sizing — larger or special applications require thorough analysis and direct contact with Des-Case engineering.
Summary
- DES-CASE DC-ND Non-Desiccant Breathers filter to 0.3 µm absolute using ePTFE media — no desiccant required.
- Operating temperature range is -40°F to 300°F for both DC-ND-2 and DC-ND-35 models.
- The DC-ND-2 handles up to 0.67 cfm and 5 gpm; the DC-ND-35 scales to 40 cfm and 300 gpm at 1 psi ΔP.
- Compatible with mineral oils, most synthetic oils, and diesel fuels; ideal for water-based fluid and low-humidity applications.
- Reservoir sizing beyond 15 gallons or in special circumstances requires direct consultation with Des-Case technical support.
Products discussed in this episode
Browse all DES-CASE products on PE Energy Industrial Supply.
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