For plant equipment to function properly, they must be free of debris, varnish and contaminates. Two common techniques for system cleaning are high-velocity oil flushing and air blowing. But when should you use air blowing vs. HVOF?
Air blowing is a somewhat more versatile and cost-effective way to remove loose debris and hydro testing fluid, though HVOF is better suited for more robust applications. Fundamentally, High-Velocity Oil Flushing (HVOF) is an efficient way to eliminate debris and varnish from pipelines as well as newly constructed systems. An HVOF procedure involves flushing oil at a specifically engineered force so that the circulating fluid removes debris from the internal pipe surfaces. The fluid is then filtered and re-injected to remove more debris.
Similarly, Air blowing removes construction debris and other contaminants from process and piping systems. Air is forced through piping and systems at high speeds, scrapping debris and blowing them out. The blows are sequenced at a minimum cleaning force ratio (CFR), which is 1.5 times the force under normal operating conditions. There are several types of air blowing methods, including Decompression (rapid pressurizing and de-pressurizing), Pulse/Puffing (Valves Puff Air in Batches), and Continuous Blowing.
HVOF and Air Blowing: Advantages and Disadvantages
Both the HVOF and air blowing methods come with advantages and disadvantages. summarized in the chart below:
Selecting the right cleaning method depends on several factors. Age of the system, size and shape of the piping, cleaning goals, and level of contamination are a few of the more important factors. Using a pre-commission or preventive maintenance partner experienced in cleaning is the best way to ensure the right method is selected and executed safely and quickly.
About Energy Services International
Energy Services International provides complete lubricant analysis, cleaning, varnish removal and more to the oil and gas, energy, petrochemical, and refinery industries.
At ESI, we:
- Are a one-stop shop for all commissioning services
- Offer deep experience
- Use in-house planning, engineering, and procedure development
Our team of highly trained, certified professionals have served some of the biggest plants worldwide. We deliver a job well done, time and again, on time, on schedule and on-budget. In the process, we build trusting relationships that stand the test of time.