Shell & Tube
Koch Heat Transfer has extensive experience in the construction, fabrication, qualification and design of Heat Exchangers, high-pressure vessels, separators and reactors up to 200 ton weight, with up to 250 Barg shellside using Breech-Lock and 1,000 tubeside Barg using Taper-Lok ®, depending on the diameter.
Over 800 BREECH-LOCK high pressure heat exchangers are in operation worldwide. Approximately 400 have been manufactured by KHT.
BREECH LOCK CLOSURE
- Extremely Reliable High Pressure Sealing
- Seating of Gaskets by Small Diameter Bolts
- Absence of Threaded Holes in Forging or in Cladding
- Possibility if In-Service
- Seating of Internal Gaskets
- Easy dismantling/re-assembly for Inspection
- No Need of Welding During Re-Assembly
- Reduced Maintenance Times and Cranage Costs with Our Special Dismantling Jig
Heat exchangers provide a higher heat transfer coefficient than any other type of tubular heat exchanger which avoids the need for baffles. The unique helix shaped tubes are arranged in a triangular pattern. Each tube is firmly and frequently supported by adjacent tubes, as shown in illustration above, yet fluid swirls freely along its length. This support system eliminates tube vibration, which is a common problem in some heat exchanger services. The twist arrangement for baffle-free support with gaps aligned between the tubes also provides for easier cleaning on the shellside.
The TWISTED TUBE heat exchangers are round at each end, allowing for conventional tube-to-tubesheet joints to be used.
Twisted Tube Bundle
Hairpin heat exchangers
Hairpin heat exchangers utilize true counter-current flow to maximize the temperature differences between shellside and tubeside fluids, resulting in less surface area required for a given duty.
This arrangement allows for a temperature cross (when the hot fluid outlet temperature is below the cold fluid outlet temperature) and a close temperature approach for maximum heat recovery.
Our closure designs provide an effective means of providing a removable tube bundle for a variety of design conditions and applications. All of our closures have the following features:
A hairpin heat exchanger should be considered when one or more of the following conditions exist:
- The process results in a temperature cross.
- High pressure tubeside application.
- A low allowable pressure drop is required on one side.
- Cyclic service.
- High flowrate ratios between shellside and tubeside fluids.
- High terminal temperature differences (300°F or greater).
- When an augmentation device will enhance the heat transfer coefficient.
- When the exchanger is subject to thermal shock.
- When flow induced vibration may be a problem.
- When heating or cooling vapors.
- When complete vaporization is required.
- When solids are present in the process stream.
- When the mechanical advantages of a hairpin are preferred.