Historically, high alloy downhole completion equipment has been manufactured from precipitation hardened “PH” nickel alloy bar stock. Often times starting with bar results in significant material loss, additional machining time and costs, and limitations to part lengths when compared to starting with a cold-worked nickel alloy tube.
Utilizing our job shop mill, CRA produces cold worked seamless heavy-walled tubes for mechanical applications. CRA manufactured tubes are offered to semi-finished near shape dimensions with close tolerances allowing for significant reduction in machining hours and cost. Providing reliable, quality products produced with accelerated deliveries creates opportunities to meet customer’s delivery requirements while reducing inventory risk.
Presented below are comparisons of the two most commonly used ph nickel alloys, 925 & 718, to alternative cold worked nickel alloys, 2535 & 2550.
Standard API Strength Classifications
These nickel alloys are all suitable for most sour service applications. Alloy 2550, with its high Pitting Resistance Equivalent Number (PREN), is also suitable for injection wells and high chloride environments. Where hydrogen embrittlement is a concern, the cold worked nickel alloys are preferred. While hydrogen embrittlement failures have been experienced with high strength ph nickel alloys, no such failures have been reported with the cold worked alloys and laboratory studies have shown them to be essentially immune.
*While every effort has been made to ensure the accuracy of the above review, assessment, conclusions, and report, the appropriateness of their application and their interpretation remain the sole responsibility of the user.