Removable blankets

Anything that gets opened, inspected or serviced: gate and globe valves, control valves, flange pairs, strainers, manways, heat exchanger heads and channel covers, pump casings, expansion joints and autoclave doors. If maintenance touches it twice a year, hard insulation is the wrong answer — a removable cover is.

They also solve the access problem on otherwise hard-insulated systems. On a pipe run we hard-insulate the straight pipe and sew blankets for the valves, so the run stays sealed and the valves stay serviceable. Same logic on a tank: fixed insulation on the shell, removable covers on the manway and nozzles.

A bare 6-inch gate valve loses about as much heat as four to five feet of bare pipe of the same size — all that cast body and bolted flange is surface area, and at steam temperature every square foot of bare steel sheds roughly 780 Btu per hour. A boiler room with a dozen naked valves is quietly running an extra burner.

A fitted cover recovers about 85 percent of that loss. A dozen 6-inch valve covers on 350°F lines running around the clock save on the order of $5,400 a year, and the set costs about $4,800–7,700, so payback lands near 14 months. There is a safety line item too: a valve at 350°F is an injury waiting at hand height, and the industry design target for touchable surfaces is about 140°F per ASTM C1055.

The shell is silicone-coated fiberglass cloth — it sheds water and oil, takes plant abuse, and handles the heat. Inside goes high-temperature needled insulation blanket sized to the service temperature, and where the hot face needs it — steam traps, superheated lines, anything with sharp studs or bolt heads — we line the inside with stainless steel mesh.

Closure is D-rings with lacing wire, or straps and buckles where the crew prefers them; either way the cover cinches tight to the body with no chimney gaps at the stem or flanges, because a loose cover with air moving through it gives back a big share of the savings. Every cover is patterned from measurements we take on your valve, not picked from a catalog of approximate sizes.

Hard insulation is cheaper per square foot and seals better on things that never open — that is why straight pipe gets sections and jacket, not blankets. But on a valve, hard insulation dies at the first repack: the mechanic cuts it off, the jacket goes in the scrap bin, and the valve stays bare until someone budgets to re-insulate it. Usually nobody does.

A removable cover breaks that cycle. It comes off in a minute or two by hand, sits on the floor during the work, and goes back on the same shift — no insulation contractor, no purchase order, no bare valve for the next five years. The full comparison is in removable vs. permanent insulation.

Per cover, by line size: valves on 1–3 inch pipe run $220–460, 4-inch $320–520, 6-inch $400–640, 8-inch $480–760, and 12-inch $620–980. Odd shapes — exchanger heads, manways, pump casings — price by the pattern, in the same range for comparable surface area. Small orders carry the shop's $1,500 job minimum.

The count is the part people get wrong, so we do it for you. On the free walk-down we tag and count every bare valve and fitting, shoot each one with the IR gun, and hand you a written estimate within 24 hours — a per-cover list you can rank by payback, not a lump sum. Or get ahead of us and run your count through the calculator first.

Cost and energy figures on this page are planning examples, not measured results from a CJM project. Material, thickness and installation selections depend on the actual conditions and site requirements.