Estis Compression: From Cooling Gap to Improved Thermal Control
Estis Compression
Estis Compression, now a part of Flowco, Inc., is a leading provider of natural gas compression leasing, sales, installation, service, and maintenance. Headquartered in Kilgore, Texas, Estis operates across major oil and gas production regions in the United States. As an industry leader in well pad compression services, Estis continually seeks design improvements to optimize performance.
One key operational challenge is maintaining optimal process gas temperatures to ensure efficiency and prevent hydrate formation.
Recognizing a gap in cooling control, Estis partnered with Horton Inc., a thermal management solutions expert, to explore the implementation of advanced fan control technologies.
The overcooling Issue
Estis identified a widespread issue: overcooling of process gas and jacket water due to constant-speed, direct-drive fans.
This problem is especially prevalent in colder months, even with manual or pneumatic louvers in place. Overcooling can lead to hydrate formation, which risks damaging compressors or taking them offline for extended periods. Additionally, excessive cooling forces operators to flare or recycle high-BTU gas, reducing efficiency and increasing costs. Additionally, excessive cooling forces operators to flare or recycle high-BTU gas, reducing efficiency and increasing costs. Maintaining discharge temperatures within customer specifications proved difficult, and increased service calls and maintenance reduced uptime. Initial workarounds—such as manually adjusting louvers or covering radiators—offered inconsistent results. Estis needed a more precise, automated method to control airflow and temperature.
Horton: Advancing Estis’ Thermal Control
Horton, with decades of experience in thermal management for industries such as trucking, mining, power generation, and agriculture, proposed a customized solution. Building on a fan drive system originally developed for mining haul trucks, Horton created a prototype fan drive compatible with the industry-standard fan used in Estis compressors. The system dynamically adjusted fan speed based on real-time data from multiple process gas temperature sensors, jacket water, and compressor oil temperatures. This data-driven approach enabled precise fan speed control according to customized performance maps.
Following successful winter field tests in Texas, Horton developed a refined, ground-up solution: the High Torque Pulley Clutch. This design replaces the existing driven sheave on the fan shaft, requiring minimal changes to the compressor package. After programming temperature setpoints and connecting the wiring harness, the clutch modulates fan speed precisely—working in tandem with automatic louvers to deliver optimal temperature control.
Consistent cooling in all conditions
During extended testing across both winter and summer seasons, the system demonstrated a significant improvement in thermal control. Average fan speed dropped to 175 RPM—down from the previous constant speed of approximately 510 RPM—with brief increases during peak demand.
Process gas temperatures were maintained within optimal ranges, preventing a majority of the scrubber fallout and subsequent scrubber dumps.
The system successfully decoupled process gas and jacket water temperatures from ambient conditions, ensuring stable and efficient compressor operation year-round.