A spiral tube heat exchanger is a coil assembly fitted in a compact shell that optimizes heat transfer efficiency and space. Every Sentry® spiral assembly has welded tube to manifold joints for durability and strength. The coil assembly is welded to a head and fitted in a compact shell. The spaces or gaps between the coils of the spiral tube bundle become the shell side flow path.
 
Typical applications include:

• Pump seal coolers
• Sample coolers
• Inter/after coolers
• Acid heaters/coolers
• Instant hot water heaters
• Process condensers

Benefits

The spiral shape of the flow for the tubeside and shellside fluids creates centrifugal force and secondary circulating flow that enhances the heat transfer on both sides in a true counterflow arrangement. Since there are a variety of multiple parallel tube configurations (diameter, number and length), efficiency is not compromised by limited shell diameter sizes as it can be with shell and tube designs.

The profile of a spiral is compact and fits in a smaller footprint than a shell and tube design. Since the tube bundle is coiled, space requirements for tube bundle removal are significantly reduced.

When exotic material is required, a spiral tube heat exchanger minimizes the material used since manifolds replace the channels, heads and tubesheets of a conventional shell and tube design. The shell side is usually smaller than a comparable shell and tube design and there are no requirements for tube supports or pass dividers.

Features

• Up to 40% more efficient than a typical shell and tube heat exchanger
• Pressure ratings up to 5000 psi (345 bar)
• Temperature ratings up to 1000°F (540°C)
• Compact and lightweight
• Highly resistant to thermal and pressure shock
• Standard tube-side material is 316 Stainless Steel; shell-side is carbon steel; exotic materials available for both sides
• Bolted or welded shell construction
• Heat transfer areas up to 150 ft2 (14 m2)
• ASME "U" stamp available

Dual Tube Coil Heat Exchanger

Helically wound tube-in-tube full counter flow heat exchangers well suited for a variety of applications. Widely used for gas/vapor condensation.

• Variety of lower flow applications
• Fully drainable inner and outer coil
• No dead spots or crevices
• Wide variety of materials available including copper, 316 Stainless Steel, Inconel® 625, Hastelloy®, titanium, zirconium, PTFE, and a variety of other nickel and stainless steel alloys
• Tri-clamp and electropolished units to meet sanitary requirements
• Direct replacement for Parker DHTC

Single tube helical coil heat exchangers are well suited for OEM applications including oil coolers, sump coolers, sample coolers and other high pressure, high temperature, low flow applications.

• Pressure ratings up to 5000 psi (345 bar)
• Temperature ratings up to 1100°F (593°C)
• Compact and lightweight
• No dead spots or crevices
• Highly resistant to thermal and pressure shock
• Removable shell on most models
• Standard 316 Stainless Steel tube-side construction with other exotic materials available
• ASME "U" stamp available

Blowdown heat recovery

The Sentry® XC blowdown system provides the best performance of any boiler heat recovery product available. The XC blowdown system maximizes boiler blowdown heat recovery while controlling solids with a reliable mechanical automatic proportional control valve. The proportional thermostatic control valve regulates blowdown flow to be counter-current with and proportional to make up water flow. This means that blowdown energy is always transferred to the make up flow providing for 90%+ heat recovery. The valve is simple to adjust and maintain.

Our rugged ASME code stamped heat exchanger is specially designed for severe blowdown service. It has a removable bundle, stainless steel tubes and extra heavy U bends. Rated for up to 250 psig (17 barg). Up to six boilers can be connected to a single system.

Benefits:

The XC blowdown system is specifically designed to eliminate the twin hazards of blowdown systems: flash steam, which destroys heat exchangers, valves and piping, and overheated makeup, which scales the heat exchanger and liberates dissolved gases that corrode the exchanger, piping and deaerator inlet.

All systems are completely pre-piped for a broad range of boiler capacities, and installation is simple.

Features:

• One to six boilers in the same recovery unit
• Typically recovers 90% of heat lost during blowdown
• Quick payback in energy savings
• Boiler pressure ratings from 35 to 250 psig (2.4 to 17.2 barg) for a broad range of boiler capacities