Select Inner Layer for Choke Line in H2S Environment

Four conditions are listed below for helping you select proper inner layer for kelly hose / drilling hose / choke line.

• If possible, use HNBR for sour nature gas, oil, or water at temperatures under 250 °F (121 °C). It can bear most of the sour applications and the relative cost is much lower than the PTFE or the Fluoroelastomer (FKM). Meanwhile, the material is new and only several parts set up. You need to check the availability before making the final choice.
• If the temperature is between 250 °F (121 °C) and 400 °F (204 °C), use PTFE for nature gas, oil or water applications.
• On condition that the H2S concentration is lower than 10%, and the temperature is below 250 °F (121 °C), we could use FKM for sour natural gas, oil and water applications.
• Only when the H2S concentration is less than 1% and temperatures is under 150 °F (66 °C), we could use the conventional nitrile.