A limpet coil jacketed vessel uses an external helical half-round or full-round pipe coil welded to the vessel outer wall, carrying heating or cooling media. Rated to 15 bar, with superior structural strength versus standard annular jackets, it delivers U = 300–1,400 W/m²·K across −20°C to 250°C. Ideal for high-pressure steam systems, thermal oil circuits, and reactors requiring robust thermal cycling resistance.
Heating or cooling media flows through the continuous external coil in a helical path from bottom to top — or in counter-current configuration for uniform temperature distribution. The coil’s intimate wall contact maximises conductive heat transfer through the vessel wall into the process. Coil pitch, coil diameter, and number of turns are engineered to deliver the required heat duty. High-pressure rating (up to 15 bar) enables high-temperature steam operation above 180°C.
Challenges
Lower Heat Transfer Area than Half-Pipe
Single coil row provides less surface area per unit vessel height.
External Coil Insulation Requirement
Exposed coil surface loses heat to atmosphere without lagging.
Thermal Cycling Stress on Coil Welds
Repeated heating/cooling cycles fatigue fillet welds at coil-to-wall attachment points.
Uneven Coil Coverage in Conical Base
Coil pitch limits thermal coverage of conical or dished vessel base sections.
CIP Inaccessibility of Coil-Wall Gap
External gap between coil and vessel wall may trap contamination in food/pharma use.
Solutions
- Double-Coil (Inner + Outer) Configuration: Doubles effective heat transfer area; provides redundant thermal circuit.
- Full External Insulation Cladding: Mineral wool + SS cladding reduces external heat loss to <2% of heat duty.
- Full-Penetration TIG Weld at Coil Attachment: Continuous fusion weld eliminates stress concentration at coil root.
- Conical Base Coil Extension or Base Jacket: Separate dimple jacket on conical base ensures complete thermal coverage.
- Pressure Testing to 1.5× MAWP: Hydraulic test before dispatch validates weld integrity and media containment.
Applications
- Chemical: High-pressure polymerisation, exothermic reactions, thermal oil-heated resin synthesis.
- Pharmaceutical: High-temperature API synthesis, autoclave-grade reactor heating, solvent recovery.
- Food & Beverage: High-pressure cooking, sterilisation, confectionery production above 150°C.
- Dairy: UHT pasteurisation support, high-temperature whey processing.
- Specialty Chemicals: Thermal oil-heated bitumen, wax, and high-melting-point material processing.
Models & Capacities
2B — Limpet Coil Jacketed Vessel (JV-LC) — 100 L to 10,000 L — −20 to 250°C — Up to 15 bar — U 300–1,400 W/m²·K — Steam / HW / Thermal Oil | ||||||||||
Model | Capacity [L] | Coil Pressure [bar] | Motor [kW] | Op. Temp [°C] | Media Type | U [W/m²·K] | Coil Area [m²] | Vessel H × Ø [mm] | Overall H [mm] | Weight [kg] |
JV-LC-100 | 100 | Up to 15 | 0.75 – 1.5 | −20 to 250 | Steam / HW / Oil | 300 – 1,200 | 0.3 | Ø500 × 620 | 1,900 | 160 |
JV-LC-300 | 300 | Up to 15 | 1.5 – 3.0 | −20 to 250 | Steam / HW / Oil | 350 – 1,300 | 0.8 | Ø700 × 950 | 2,500 | 320 |
JV-LC-500 | 500 | Up to 15 | 2.2 – 4.0 | −20 to 250 | Steam / HW / Oil | 350 – 1,350 | 1.2 | Ø850 × 1,100 | 3,000 | 500 |
JV-LC-1000 | 1,000 | Up to 15 | 4.0 – 7.5 | −20 to 250 | Steam / HW / Oil | 400 – 1,400 | 2.0 | Ø1,100 × 1,250 | 3,600 | 850 |
JV-LC-5000 | 5,000 | Up to 15 | 11 – 22 | −20 to 250 | Steam / HW / Oil | 350 – 1,300 | 8.0 | Ø2,000 × 1,900 | 5,500 | 3,200 |
JV-LC-10000 | 10,000 | Up to 15 | 22 – 45 | −20 to 250 | Steam / HW / Oil | 300 – 1,200 | 14 | Ø2,600 × 2,600 | 7,200 | 6,500 |