7BBL Conical Unitank: What It Actually Does in a Working Brewery

A 7BBL unitank is a dual-purpose vessel. It handles fermentation and conditioning in the same tank, which cuts transfer steps and reduces oxygen pickup between stages. For a brewpub running 2–4 brews per week, that matters more than a spec sheet suggests. You knock out into one tank, dry hop, crash cool, carbonate, and serve or package without racking to a separate bright beer tank.

Build Details That Decide Service Life

We fabricate these tanks from SUS304 as standard, with 316L available for sour programs or aggressive CIP chemistry. The cone is typically 60 degrees for yeast drop; a shallower 45-degree cone gives more usable volume but drains slower and leaves more hop sludge behind.

Wall thickness: 3mm for the shell and cone, 2mm for the outer jacket cladding. Interior welds are ground flush and passivated, then polished to a 0.4–0.6μm Ra finish on product contact surfaces. Oxide scale left in a weld seam is where pitting starts, so we acid-passivate every interior joint before pressure testing.

Cooling, Pressure, and Cleaning

Single-zone or dual-zone dimple jackets cover the cone and lower cylinder. In practice, a single jacket zone is fine up to 7BBL if your glycol supply holds 28–30°F. Dual zone helps when you crash cool from 68°F to 34°F in under 24 hours.

Working pressure is 15 PSI, tested to 30 PSI, with a pressure relief valve and a separate sample/carbonation port. Do not confuse working pressure with the PRV setting — the PRV is your last line of defense, not your operating target.

For CIP, we fit a rotating spray ball on the top manway plus a racking arm at the cone. A dedicated CIP port keeps caustic and acid cycles out of your sample valve threads.

Typical Specifications

Questions Buyers Ask Before Ordering

Is 7BBL the right size? It fits brewpubs and small production houses. If you plan to distribute, size for your largest expected batch — a tank that is always full ferments more consistently than one running half loads.

Do I need glycol on both zones? Only if you crash cool hard or brew lagers with long cold conditioning.

Can I carbonate in the unitank? Yes, with a carb stone and PRV rated for your target volumes. Confirm the valve configuration before fabrication — adding ports later costs more than ordering them now.

Before requesting a quote, have these ready: batch size in BBL, beer styles, number of tanks, available floor space, ceiling height, glycol capacity, and your preferred connection standard. Tell us your batch size, beer type, number of fermentation tanks and available space. We can recommend the tank volume, cooling area and configuration for your brewery.