Thursday, November 17, 2016

Shell and Tube Heat Exchanger Refurbishment

shell and tube heat exchangers tube bundle removed for refurbish
Two shell and tube heat exchangers getting refurbished
at industrial site. Tube bundles have been removed.
Shell and tube heat exchangers are regularly employed throughout industrial and commercial sites as a means of producing heated or cooled fluids. They consist of a pressure vessel and an internal tube bundle. The flow paths of the pressure vessel and the tube bundle are isolated from one another, giving a shell and tube heat exchanger four nominal connections.

  • Vessel inlet
  • Vessel outlet
  • Tube bundle inlet
  • Tube bundle outlet
Most often, the subject process fluid to be heated or cooled will flow through the pressure vessel, contacting the surface of the tube bundle contained within. If the heat transfer fluid flowing through the tubes is warmer than the process fluid in the vessel, heat will conduct through the tube wall into the process fluid, increasing its temperature. If the fluid in the tube bundle is cooler than the process fluid in the vessel, the process operates in the reverse fashion. Construction details of shell and tube heat exchangers can vary, but the basic operating scheme remains constant.

The lack of moving parts and ruggedly constructed nature of shell and tube heat exchangers tends to grant them a good measure of longevity for most applications. Regardless of any exceptions to that statement, there will eventually come a time when refurbishment or replacement is needed. If the pressure vessel is serviceable, or can be made so with a reasonable amount of cost, replacing the tube bundle may be the main element of an operation aimed at returning the heat exchanger to like new service.

Tube bundles are just that, bundles of tubes. With the right set of dimensional information and specifications, an identical fabrication can be purchased and put in place. It is not always necessary to revisit the original manufacturer. If drawings are still on file for the unit, sufficient information can be gleaned from them to produce a replacement tube bundle that will provide rated performance.

Ordering up a replacement tube bundle is not complicated, but the operation can be smoothed out through contact with involvement of an experienced engineer that can make sure all the necessary information is on hand and step you through the process. 

Tuesday, November 8, 2016

Spiral-Trol Valve Disassembly Video

globe valves control valves pneumatic actuator
Globe control valves with pneumatic actuators
Spirax-Sarco
Spirax-Sarco is a globally recognized manufacturer of valves, traps, and a host of other steam system specialties. Their Spira-Trol line of globe valves can be employed throughout a steam of other process fluid system to provide accurate flow regulation. The valves are available with several options of electric or pneumatic actuators, as well as positioning controllers.

The video included below provides a demonstration of the simplicity involved in disassembling the valve in-line for regular maintenance or inspection. The video is short, as is the length of time needed to access the valve internals. These valves are designed for easy maintenance.

Share your fluid process and steam control challenges with application experts. The combination of your process knowledge and their product application expertise will deliver effective solutions.

Tuesday, November 1, 2016

New High Pressure Float Type Steam Trap

steam trap high pressure float type
Model FTC62 High Pressure Steam Trap
Courtesy Spriax Sarco
Steam is utilized by industrial operations as a source of heat and power. Commercial and institutional facilities widely employ steam as a heating source. The overall cost of operating a steam system is generally significant, regardless of the size of the organization. Designing a system to deliver efficient performance and maintaining that performance throughout many years of expected operation requires continuous monitoring and attention.

One facet of efficient operation is to remove condensate from the steam system and return it to the boiler. This operation is the primary function of a steam trap. Additionally, a steam trap will also remove non-condensible vapor from the system. Liquid water and non-condensible vapor both will undermine efficiency in a common steam system.

There are many versions of steam traps available, and it is important to match the capacity and performance range of the trap to the steam system. Spirax-Sarco, globally recognized steam system specialties manufacturer, has added  a new steam trap model series to their already extensive offering.

The FT62 Series, which is available with a carbon steel (FTC62) or stainless steel (FTS62) body, has stainless steel internal components. It is intended for application on light and heavy condensate loads on steam systems with differential pressure up to 900 psig (62 bar).  The unit includes an integral air vent and an easily maintainable in-line strainer.

More information is provided below, with good illustration of the exterior and interior setup of the steam trap. Share your steam system requirements and challenges with experienced application specialists, combining your facility and process knowledge with their product application expertise to develop effective solutions.