Dust Collection System

Dust Collection System for Plasma Cutter

January 2026 - July 2026

Context

This project involved designing a dust collection system for an industrial fabrication shop to work in conjunction with their new plasma cutter. I served as the design engineer and project manager, responsible for requirements gathering, system sizing, specifying custom equipment, and client coordination from project conception through closeout and commissioning.

Challenge

The customer requested a dust collection solution for their brand new plasma cutter. My challenge was to design a dust collection system compatible with the plasma cutter. After conducting multiple meetings with the customer, the following driving requirements became apparent:

The system shall provide continuous duty dust collection for the plasma cutter.
The system shall exhaust outdoors.
The equipment and ductwork shall be designed and installed in a manner to minimize used floorspace.

Desing Approach

Working closely with the customer and staying within the guiding requirements, the following key design decisions were made:

1) Use of a cyclonic pre-separator

Pros: Removes heavy particulate from the airstream, and acts as a spark cooler mitigating the risk of a fire.
Cons: Adds an additional 3.48 inches w.g. static pressure to the system therefore requiring a larger 15HP blower motor, which will add cost.
Justification: The added upfront equipment cost is necessary to eliminate sparks from the airstream and reduce the risk of a fire.

2) 12 filter Donaldson DFE cartridge-style dust collector

Pros: Cartridge style filters handle fine, dry dust. 12 filters with 3048 sq.ft of filter media in a small footprint allows for a low air to media ratio of 1:1.38.
Cons: Cartridge filters are less resistant to abrasion.
Justification: The cyclonic pre-separator handles the abrasive material, and the cartridge dust collector handles the leftover fine particulate. This design also extends filter life lowering operating costs.

3) Implementation of automatic airflow controller with variable frequency drive

Pros: Automatically monitors system airflow and adjusts fan to maintain 4200 CFM. All the operator needs to do is press start, and the system self monitors and adjusts autonomously
Cons: Adds design complexity and cost.
Justification: Allows for in-field tuning of airflow to best support customer’s manufacturing process, and maintains target airflow. It also lowers the electricity usage of the system significantly.

Technical Specifications

System Overview:

Plasma cutter recommended airflow 3800-4200 CFM
Target airflow (Q): 4200 CFM

14” ductwork from plasma cutter to cyclone

Velocity (V): 3930 FPM
Static pressure drop (ΔP): 0.44 w.g.

Cyclone pre-separator:

Minimum inlet velocity (Vmin): 3500 FPM
Inlet velocity (Vin): 3930 FPM
Static pressure drop (ΔP): 3.48 w.g.

16” ductwork from cyclone to dust collector

Velocity (V): 3010 FMP
Static pressure drop (ΔP): 1.18 w.g.

12 filter cartridge duct collector and motor

Filter media area: 3048 sqft
Air to cloth ratio: 1:1.38
Static pressure drop (ΔP): 1.5 w.g. with clean filters, 3.5 w.g. end of filter life
Total system static pressure drop: 9.6 w.g. (including 1 w.g. hood losses)
Motor size: 15HP

Outcome

I completed system startup and verification in July 2026, with my team supporting equipment installation to bring the project in on schedule. I commissioned the system and set the automatic airflow control at 3,900 CFM (below the 4,200 CFM maximum) to reduce dust loading on the cartridge filters and extend filter life, while maintaining sufficient capture for the plasma cutting process. Airflow at this setting was verified via pitot tube, and the customer was notified that airflow can be increased up to the 4,200 CFM design maximum through the VFD control if their process demands greater capture in the future. In the weeks following startup, the customer confirmed that the dust collection equipment and plasma cutting process are working as intended.