Boronizing in Masoneilan Control Valves

Unmatched Erosion Resistance for Demanding Environments.

Your control valves are up against more than just pressure – they’re fighting off constant wear, abrasive grit, and challenging flow conditions every day. Most coatings can only take you so far. At Fluid Tech, we’ve seen first-hand how quickly a standard valve trim can get chewed up in harsh service. That’s why we put our trust in boronized Masoneilan valves, because sometimes, you just need something tougher.

What Makes Boronizing Different?

Boronizing (also called boriding) isn’t your run-of-the-mill surface coating. It’s a process that takes boron and actually diffuses it right into the metal’s surface, turning it into an ultra-hard boride layer. So instead of a thin film sitting on top, you end up with a whole new hardened zone that stands up to serious punishment. Think of it as a real upgrade to your valve’s armour, giving your Masoneilan valves the muscle they need for the roughest process environments. Standard treatments just can’t keep up

Key Features of Boronized Masoneilan Valves

• Exceptional Hardness: Iron borides formed during boronizing reach hardness levels between HV 1500 and 1800. For nickel and cobalt-based materials, the hardness shoots up to HV 2200–2800.
• Deep Case Depth: On steels with low alloy content, boronizing creates a hardened layer up to 0.010” deep – ideal for resisting long-term erosion.
• High Temperature Stability: Boronized layers remain stable up to 1500°F, much higher than most conventional coatings can handle.
• Consistent Protection on Complex Parts: Because boronizing isn’t a line-of-sight process, even intricate valve trims and parts with odd geometries get full protection.

Excellent Wear and Abrasion Resistance: Field data and third-party research confirm that boronized Masoneilan valves experience up to 10 times less material loss compared to carburized or nitrided equivalents.

Masoneilan Rotary Control Valves

The Boronizing Process – Built for Longevity

The most widely used boronizing method is pack cementation. Masoneilan valve trims are placed in a special container packed with boride salts. The entire assembly is then heated in a conventional oven at roughly 1700°F for 12–24 hours. At that temperature, boron-rich gases permeate the component, diffusing deep into the surface and forming ultra-hard borides

What does this mean for your operation? Every contact surface exposed to process flow – especially trims that see high-velocity fluids or slurries, gets long-lasting protection.

Boronizing vs. Nitriding: When Tough Isn’t Tough Enough

Nitriding is a familiar technology for hardening valve components and is often used for “standard” severe service conditions. But in the harshest applications – severe flashing, cavitation, or fluids containing sand and abrasive particles – boronizing is the better choice.

• Temperature Advantage: Boronizing is stable at much higher temperatures (up to 1500°F), while nitriding starts to lose effectiveness above 1000°F.
• Full Geometry Coverage: Because it’s not limited to “line of sight,” boronizing covers every nook and cranny, so even trims with complicated shapes get protected.
• Wear Resistance: The boronized layer reduces erosive material loss by a factor of ten compared to nitrided or carburized steels.

Example: In mines or mineral processing plants, Masoneilan boronized valves regularly outperform conventional trims, holding up under slurries and abrasive fluids that would quickly erode untreated surfaces.

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