The Lee Company SDBB Series is a single-coil miniature 3-way pilot solenoid valve engineered for extreme-environment fluid control across aerospace, defense, motorsport, space, and oil & gas applications. Its 0.875-inch diameter flange body combines a pressure rating of 3000–5000 psi with an operating temperature range of -65°F to +275°F, driven by a low-power 7.8W magnetic circuit with ≤15 ms pull-in response at 28V DC.

What Is MultiSeal Technology and Why Does It Replace O-Rings?

Lee's patented MultiSeal porting system uses polyamide-imide seal elements integrated into the valve body, allowing two ports to be sealed within the same axial plane without O-rings or back-up rings. This provides 360° port placement flexibility, eliminates seal extrusion failures under high pressure, and simplifies manifold design by removing the need for individual port seal grooves. The result is a lighter, more compact fluid control package with fewer potential leak paths — critical in weight-sensitive aerospace and motorsport systems.

What Fluids and Environments Is the SDBB Rated For?

Wetted materials include 15-5 PH CRES body and ball seat, 440C CRES ball and pin, and 302 CRES spring — all passivated per aerospace material specifications. The valve is compatible with MIL-PRF-83282, MIL-PRF-5606, Skydrol (phosphate ester), and other hydraulic fluids. Internal leakage is controlled to ≤1 cc/min, with zero external leakage across the full pressure and temperature range. Rated service life is 1,000,000 cycles, and the integral 0.004-inch filter screen protects the seat from contamination.

Frequently Asked Questions

What electrical interface options does the SDBB Series offer?

The SDBB is available with rear lead-wire termination or a connector with gold-plated shell and pins for bayonet-style mating. Nominal operating voltage is 18–32V DC (28V DC nominal), with a coil resistance of 92–108 Ω and pull-in voltage of approximately 18V DC. A dual-coil variant is available for applications requiring electrical redundancy.

How does the Lohm rate relate to conventional flow coefficients?

The Lee Company uses Lohm rates (liquid ohms) rather than Cv or Kv to characterise flow resistance. The SDBB is offered in three ratings — 1800 Lohms (3000 psi), 2200 Lohms (4000 psi), and 2800 Lohms (5000 psi) — with lower Lohm values indicating higher flow capacity. This system allows direct calculation of pressure drop versus flow for incompressible fluids using Lee's published Lohm laws.