Category Archives for LTX Units and Line Heaters

LTX Coil Sizing – Coil Lengths

With the known temperatures on each end of the coil, the heat duty for each coil can be calculated from the heat transfer theory. Since the bath is at a constant temperature, LMTD can be calculated as: The overall film … Continue reading

16. September 2009 by Jack
Categories: Coil Sizing | Tags: | Leave a comment

LTX Coil Sizing – Choose Wall Thickness

Before choosing a wall thickness it is necessary to choose a pressure rating for the coil. Typically, the high-pressure coil (L1) is rated for the shut-in pressure of the well, and the low-pressure coil (L2) is rated for the maximum … Continue reading

16. September 2009 by Jack
Categories: Coil Sizing | Tags: | Leave a comment

LTX Coil Sizing – Choose Coil Diameter

Erosional flow criteria will almost always govern in choosing the diameter. Sometimes it is necessary to check for pressure drop in the coil. Typically, pressure drop will not be important since the whole purpose of the line heater is to … Continue reading

16. September 2009 by Jack
Categories: Coil Sizing | Tags: | Leave a comment

LTX Coil Sizing – Choose Temperatures

In order to choose the coil length and diameter, a temperature must first be chosen upstream of the choke; the higher Th the longer the coil L] and the shorter the coil L2. In Heat Transfer Theory we showed that … Continue reading

16. September 2009 by Jack
Categories: Coil Sizing | Tags: | Leave a comment

Fire Tube Size

The area of the fire tube is normally calculated based on a heat flux rate of 10,000 Btu/hr-ft2. The fire-tube length can be determined from: where L = fire tube length, ft q = total heat duty, Btu/hr d = … Continue reading

16. September 2009 by Jack
Categories: LTX Units and Line Heaters | Tags: | Leave a comment

LTX Units Heat Duty

To calculate the heat duty it must be remembered that the pressure drop through the choke is instantaneous. That is, no heat is absorbed or lost, but there is a temperature change. This is an adiabatic expansion of the gas … Continue reading

15. September 2009 by Jack
Categories: LTX Units and Line Heaters | Tags: | Leave a comment

Line Heaters

As shown in Figure 5-2, the wellstream enters the first coil at its flowing tubing temperature and pressure. Alternatively, it could be choked at the wellhead to a lower pressure, as long as its temperature remains above hydrate temperature. There … Continue reading

15. September 2009 by Jack
Categories: LTX Units and Line Heaters | Tags: | Leave a comment

LTX Units

These units are designed to allow hydrates to form and to melt them with the heat of the incoming gas stream before they can plug downstream equipment. In addition, the low-temperature separation that occurs in an LTX unit results in … Continue reading

15. September 2009 by Jack
Categories: LTX Units and Line Heaters | Tags: | Leave a comment