Heat exchanger tube cleaning
The NitroJet technology blasts through the hardest deposits without damaging the tubes. Secondary waste streams are minimized through this dry process.
Shell and Tube Heat Exchanger Fundamental
Shell and tube heat exchangers can be used in a variety of industries for a various of applications. A shell and tube heat exchanger composition consists of a series of tubes. Some of the tubes or pipes contain fluid that is heated or cooled depending on a the application. Another set of tubes is used to manipulate the other, hence the first heat exchanger can provide or absorb heat. Shell and tube heat exchangers are usually conducted in high-pressure effort. In this case, heat exchanger tubing is very crucially important as it is the medium where heat is transferred.
Heat exchangers are usually composed of fluoropolymers. Fluoropolymers such as PTFE, PFA, FEP, PVDF are usually utilized in many different areas because of their versatile and tenacious character.
If you are intend to purchase a shell and tube heat exchangers, you must consider 7 critical factors before deciding to purchase one. Consider the following:
1) Heat exchanger tube diameter
The diameter of the tube can be manipulated by the provider. A key point to consider is the nature of the particular liquids used in the pipes. Smaller pipes warrant will clean faster, yet more pipes may be less effective and less compact with respect to space.
2) Thickness of the tube
The thickness of the pipe refers to several factors. Corrosion, flow resistance, axial force, pressure, and the availability of spare parts in connection with a heat exchanger tube thickness.
3) Heat exchanger shell diameter and tube length
A heat exchanger costs is directly influenced by the shell diameter and tube length. Customers who are concerned about the cost of heat exchangers questions which the longest length of pipe to provide without compromising its effectiveness. The possibility of long tubes may be limited because of the limited space, specific job specifications, capabilities and replacement.
4) Tube corrugation
The corrugation of tubes influences the performance of a shell and tube heat exchanger. Corrugated cardboard, the tube increased turbulence of fluids in turn deliver better results.
5) Tube Layout
“Tube layout ‘refers to how a heat exchanger tube is placed in the skull. To date, four major layouts to consider: triangular, twisted triangular, square and rotated square. Triangular tube facilitates a better heat transfer, while the square tubing provides a longer period of purity.
6) Tube pitch
“Tube pitch” refers to the distance between the centers of separate but interconnected tubes. A general rule determines the pitch of a pipe shall not be less than 1.25 times the outside diameter tubes.
7) Heat exchanger baffles
“Baffles” are used in shell and tube heat exchangers for liquid flow in the direct beam. Baffles prevent tubes from sagging, and can also prevent them from vibrating. Baffle spacing is important in relation to pressure drop and heat transfer. Baffles closely shared a greater pressure drop causes, but still too far apart may cause cooler spots between them.
Heat Exchanger Tubing
Heat exchanger tubing is an essential part for a shell and tube heat exchanger. The types, materials and quality of the tube depend on the application and industry. Before an engineer decides to purchase heat exchanger tubing, he needs to inspect and consider several aspects and specifications.
The engineer should first either choose which type of specification he want to refer to. It can be either Welded ASTM or Seamless ASTM.
Regardless of the industries, when an engineer needs a heat exchanger tube parts, he should search for a full service manufacturer and distributor that offers highest quality heat exchanger tubing and the one that has the largest inventories. The heat exchanger tubing company should have unique blend of manufacturing and distribution capabilities and is able to meet critical lead times. The heat exchanger company should also be very capable to offer all testing and added value services to the heat exchanger tubing specifications.
Anderson Tube is an example of a stocking distributor of high quality pressure tubing certified to SA-178 Grade A and SA-214. The company specialized in boiler tubes, condenser tubes, heat exchanger tubes, ferrules, and boiler tube plugs. The entire Anderson Tube products are made in the USA. Their customers include mechanical contractors, original equipment manufacturers, fabricators, end users, exporters, tourist railroads, utility power plants and other distributors located throughout the U.S., Canada and overseas.
Photo credited to ameritube.net 4MG7TD5JDG7K
heat exchanger basics
A ‘heat exchanger’ may be defined as equipment that transfers the energy from a hot fluid to a cold fluid. Here, the process of heating or cooling occurs. In heat exchangers the temperature of each fluid changes as it passes through the exchangers.
Examples of heat exchangers
• Intercoolers and heaters
• Regenerators; refrigeration units
• Automobile radiators
• Milk chiller of a pasteurizing plant
• Condensers and boilers in steam plant
• Evaporators
• Oil coolers of heat engine
Applications:
• Environmental Engineering
• Waste Recovery
• Manufacturing Industry
• Air – conditioning and Refrigeration
• Process chemical food industries
• Electronics
• Power Production
CLASSIFICATION
Heat exchangers may be classified according to the following main criteria:
1. Nature of heat exchanger process
2. Flow arrangement
3. Physical state of fluids
4. Geometry and construction
1. Classification based on Nature of heat exchanger process
(i) Direct contact:
Heat transfer will occurs by direct mixing of two fluids. This is preferred when the direct mixing is harmless or desirable.
Ex: cooling towers
(ii) Indirect contact:
Heat transfer will occurs through a separating wall between two fluids
Ex: Regenerators and Recuperators
2. Classification based on Flow arrangement
According to the relative directions of two fluid streams the heat exchangers are classified into the following three categories:
(i) Parallel flow or co-current flow heat exchangers
(ii) Counter-flow heat exchangers
(iii) Cross-flow heat exchangers
(i) In a parallel or co-current flow heat exchanger
As the name suggests, the two fluid streams (hot and cold) travel in the same direction. The two streams enter at one end and leave at the other end. The flow arrangement and variation of temperatures of the fluid streams in case of parallel flow heat exchangers, are shown in the below figure. It is evident from the figure that the temperature difference between the hot and cold fluids goes on decreasing from inlet to outlet.
In parallel flow, it is not possible to bring the outlet temperature of the cold fluid nearly to the inlet temperature of the hot fluid. This type of heat exchanger needs a large heat transfer area, so, it is rarely used in practice.
It is particularly useful when sudden cooling or sudden heating is required.
Examples: Oil coolers, oil heaters, water heaters etc.
(II) Counter-flow heat exchangers
In a counter-flow heat exchanger, the two fluids flow in opposite direction. The hot and cold fluids enter at the opposite ends. The flow arrangement and temperature distribution for such a heat exchanger are shown schematically in the below figure.
In this flow, it is possible to bring the outlet temperature of the cold fluid nearly to the inlet temperature of the hot fluid. This type of heat exchanger needs a small heat transfer area, so, it is widely used in practice.
Examples: Oil coolers, oil heaters, water heaters etc.
(iii) Cross-flow heat exchangers
In cross-flow heat exchangers, the two fluids (hot and cold) cross one another in space, usually at right angles. The flow arrangement and temperature distribution for such a heat exchanger are shown schematically in the below figure.
Source: enggyd.blogspot.com/2010/03/description-of-heat-exchange-equipment.html
Sandia mini-reactor fits in three-storey office space
The Sandia mini-reactor would be about the size of a two- or three-storey office building. At its heart is a small uranium core submerged in a tank of liquid sodium. The sodium capturies the high temperatures of the core and carries it to a heat exchanger, where liquid carbon dioxide then absorbs the heat. The CO2 expands rapidly, forcing its way through a jet-like turbine that spins an electric generator. It would be a closed-loop system, meaning the CO2 would be recycled over and over again.
Cleaning Shell and Tube Heat Exchangers
Tube Tech International proved that previous industry standards for cleaning such equipment with U bends were inadequate and, for the first time on this unit, Tube Tech gave not only the straight legs, but also the U sections a complete internal clean.
Tranter SUPERCHANGER® Operation & Maintenance – Plate Heat Exchanger
Who says O&M instructions have to be in print? Combining real-life footage with animation, this video offers clear instructions in 10 segments. Direct mailed to customers for added value.
An Introduction to Heat Exchanger
A heat exchanger is an equipment or device built for efficient heat transfer from one medium to another, whether the media are separated by a solid wall so that they never mix, or the media are in direct contact. Heat exchanger are widely used in refrigeration, space heating, air conditioning, power plants, chemical plants, petrochemical plants, petroleum refineries, and natural gas processing. A common example of a heat exchanger is the radiator in a car, in which the heat source, being a hot engine-cooling fluid, water, transfers heat to air flowing through the radiator.
In industry, specifically process or manufacturing plants there are other types of heat exchanger such as plate heat exchangers, spiral heat exchangers and shell and tube heat exchangers. All of these heat exchangers are special and have their dedicated purpose or function when being employed. The price, size, specification, purpose and design varies within each other.
Heat exchanger must be properly maintained in order for it to be working efficiently and effectively. Energy is being transferred from one side to the other, thus it acts like an energy saver. When the heat exchanger is no longer efficiently transferring heat, it is time for cleaning. Hence, the heat exchanger will be stopped and cleaned from scale sticking on the surface of the wall. Failing to clean the heat exchanger will result to tremendous lost of energy.
Cleaning Heat Exchanger Tubes
Heat exchangers tubes are part of the heat exchangers, which is used to efficiently transfer heat from one medium to another without mixing the fluids physically. The device has a range of applications such as space heating, cooling, power, air conditioning, petrochemical factories, chemical factories, refineries and processing of natural gas.
A typical example of this instrument is located in cars, more familiarly known as radiator, where it works as a means to transfer heat from the water of the engine, to the air through the generator. There are several types of radiators and each is crafted to suit the application where each is used.
After certain period of time of heat exchanger operation, it will be inefficient. Hence, a better way to increase the capacity of working with the heat exchanger tubes is a complete cleaning. There are a number of advantages of cleaning the heat exchanger. The first reason is to protect the system of sudden and unexpected errors. Apart from this, they will also function properly and the cleaning will also improve the efficiency of the device. Check the heat exchanger tubes at least once every three months to lengthen the life of your heat exchanger and will make you have every penny’s worth of your investment.
Since the cleaning of heat exchanger tubes is beneficial, how does one do it? What are the procedures for cleaning? Here are some points to consider:
* Pull the heat exchanger unit from any electrical devices. This is followed by removal of loose materials found close. This will prevent possible pushing of these materials towards the tube’s interior once you start brushing.
* The next thing to do is remove the material inside the tube before you use the appropriate size of the brush to clean. Nylon brush cleaning process each sound within the pipe and the removal of existing materials or furniture inside.
* Sometimes the cleaning of the interior is not enough for you by just scraping the internal walls to remove the materials of the tube. It is important that you scratch using materials that are less strong than the materials from the heat exchanger materials to avoid damaging the tubes.
* After all the above step, let the water rush through the inside, to remove other materials not perfectly taken out by scraping. It will also lighten up the interiors.
Who Invented the Electric Water Heater?
The answer to who invented the electric water heater begins around 1850 with an experiment that was created in which both water and bath, on the underneath side, were heated by gas jets. An Englishman Benjamin Maughan, however in 1868 invented the first instant water heater called “The Geyser”, a device where the water was heated as it flowed into the bath. They were known to be quite dangerous.
Maughn’s invention influenced the designs of a Norwegian mechanical engineer by the name of Edwin Ruud, who immigrated to Pittsburg. Ruud who invented the electric water heater (automatic storage) in 1889, founded the Ruud Manufacturing Company, which is still in operation today, and pioneered the advancement of them, in both the residential and commercial market.
The Water Heater is still sometimes referred to as a geyser in the UK. Other terms include: an electric water boiler, electric dispensing pot, or electric water urn.
There are various kinds of water heaters. The most common of them are the storage water heaters. Instantaneous (tankless) heaters are newer on the market, and newer still, solar heaters.
Storage Tank Water Heaters:
This is typically the kind of water heater you saw growing up, the big white tank often beside the furnace. Tank type heaters come in different varieties – gas, oil & electric. This refers to the type of burner used to heat the water. Energy efficiencies between the different types of burners on the tank water heaters can differ greatly. In this tank, cold water is used to fill the tank, and an element, usually near the top & bottom inside the tank is used to heat it. In between the inside tank and the outer shell is often insulation to help keep the water hot, without the elements having to do all of the work.
Instantaneous Water Heaters:
Instantaneous Water Heaters, also called Tankless are just that. They do not have a tank, and therefore are thought to be more energy efficient. Sometimes they are called an in-line heater, as it only heats the water it needs as it passes through, and therefore energy is not wasted by heating extra water all day that is not in use.
Other terms for Tankless are Combination, Combi Boilers, Continuous Flow, Inline, Flash, On-Demand or Instant-On Water heaters.
These particular Water Heaters are rapidly gaining in popularity and will soon become the standard. Often, one main Tankless Water Heater will be installed near the furnace, and supplemental smaller Tankless ones will be situated in tactical spots, such as a far reaching bathrooms, etc to be located right where the water is being used. This strategy saves water as well as energy, thereby making this option one of the most efficient, as well as saving on space.
Solar Water Heaters:
If you’re fortunate enough to live someplace sunny most of the year around, a solar powered water heater may be an option for you. Solar collectors are typically installed on the exterior of the building on the roof or nearby. If insufficient sunlight or at night, an automatic sensor turns off and keeps the remaining water from cooling.
For colder climates, you’re not out of luck. The evacuated tube collector solar powered heater is an alternate type of solar water heater, smaller and deemed more efficient, also roof mounted, is said to work very well in cold climates.
True to its name, the evacuated tube collector solar powered heater has a row of glass tubes which contain heat conducting rods. Inside the heating rods is antifreeze, which is in a circulating loop. The heat is captured and transferred into a heat exchanger. The result is excellent, with very low heat loss due to the fact that once the inside coating has absorbed solar radiation, the air has been evacuated from the glass tubes to create a vacuum.
Stephan Bevan writes for the Toronto Plumbing contrator: Draincom.com. If you need a water heater repair or installation please give us a call at: 
416-989-5757
.
