How to Read an Oilfield Hose Spec Sheet

A spec sheet is often the first real point of comparison between suppliers, but the terms on it aren't always self-explanatory. Working pressure, FSL rating, ID, MBR, license number, each one tells a buyer something specific, and skipping past any of them can mean missing a detail that matters for the application.

This guide walks through the fields most commonly found on an oilfield hose spec sheet and what each one actually means.

Working Pressure

Working pressure is the maximum pressure a hose is rated to handle under normal operating conditions. It's usually listed alongside a separate test pressure, the pressure the hose was tested to during qualification, which is typically higher than the working pressure as a safety margin.

A higher working pressure number isn't automatically "better." The right number is whatever matches the actual operating conditions of the application, oversizing pressure capacity doesn't add value if the application never approaches that range.

FSL Ratings

Within API standards like 7K and 16C, hoses are qualified to specific Flexible Service Level, or FSL, ratings. These reflect additional performance and safety testing beyond the base standard, covering things like cycle testing and burst performance under repeated pressure and flexing.

Two hoses can both be built to the same API standard while being qualified to different FSL levels. The FSL rating is often a more specific indicator of a hose's tested performance than the base certification alone.

Inside Diameter (ID)

ID determines flow capacity, not just physical fit. A hose with too small an ID for the application can create pressure drop or flow restriction issues, even if every other spec matches. Available ID ranges vary by product and by supplier, so this is worth confirming directly rather than assuming standard sizing applies.

Minimum Bend Radius (MBR)

MBR is the tightest radius a hose can be bent to without damaging its internal reinforcement. This matters for rig floor layout and routing, a hose bent tighter than its rated MBR is at higher risk of premature failure, even if it's otherwise rated for the application's pressure and temperature.

MBR is easy to overlook on a spec sheet, since it doesn't show up in day-to-day conversation the way pressure rating does, but it directly affects how safely a hose can be installed and routed.

Certification and License Numbers

A certification or license number is what makes a compliance claim verifiable. "API licensed" or "certified" on its own is a claim. A specific license number tied to a specific product and pressure range is evidence.

Buyers should confirm that a listed license number actually covers the specific product, size, and pressure rating being purchased, not just the supplier's company in general. Licenses are typically scoped to specific product lines, not issued as a blanket approval for everything a manufacturer makes.

Temperature Range

Working temperature range defines the conditions a hose is rated to perform in, both the low and high end. This matters as much for cold-weather operations as it does for high-heat applications, a hose rated for a wide pressure range isn't necessarily rated for the temperature extremes of a specific job site.

Comparing Two Spec Sheets Side by Side

When comparing suppliers, it helps to line up the same fields for each option: working pressure, tested pressure, FSL rating, ID, MBR, temperature range, and license number. A supplier that omits one of these fields isn't necessarily hiding something, but it's worth asking for the missing number directly rather than assuming it matches the other option.

Questions to Ask When a Spec Sheet Is Incomplete

What is the tested pressure, not just the working pressure?

  • What FSL level is this specific product qualified to?

  • What is the minimum bend radius for this hose?

  • Can you provide the specific license or certificate number for this product and pressure range?

  • What is the full working temperature range, both low and high end?

Final Thoughts

Once the working pressure, FSL rating, ID, MBR, temperature range, and license number are all on the table, buyers can compare two suppliers field by field, rather than on price alone. The same framework holds regardless of the application, whether the hose in question is rated for 500 PSI or 15,000 PSI, the fields stay the same. Only the numbers change. Copper State Rubber's full catalog lists these fields for every product line it manufactures. View or download Copper State Rubber's full catalog here.

Adam Hyman