Air Cooled Heat Exchangers for All Equipment

An air cooled heat exchanger is amongst the must-haves for all equipment. It is a commonly known fact that when a machine works hard for a prolonged period of time, it can easily heat up and damage itself. In fact, in many cases, when a machine overheats, the consequences can be direr. Factories have caught fires and burned down to the ground simply because the equipment running inside overheated and caused a fire to break out. Thus, it is very important for the equipment to have cooling systems installed inside them to keep them at low temperatures as they function. An air cooled heat exchanger is able to do exactly that. It manages to use the heat of the system to work on and it slowly turns the hot air down to cooler temperatures.

Cover plate Configuration

Some air cooled heat exchangers have a cover plate configuration system and these types are generally used in machines that are installed in refineries. They are supposed to work with machine oils and heavy hydrocarbons, cooling them down as the oils and hydrocarbons power the machines that are supposed to pump out the oil. This type of an air cooled heat exchanger is very easy to maintain. In fact, it has been designed for easy maintenance so that the costs are kept low. The cover is flanged is easily removable and allows cleaners to access the components inside. While this exchanger is quite good at the machines it is built for, it is not recommended for sensitive service applications since it limits the design pressure a lot.

Plug box Configuration

This type of an air cooled heat exchanger is full of possibilities, is highly flexible and can be used in a number of different settings. Since it can work just as well with all kinds of hydrocarbons and gases and can be fitted anywhere in the entire factory (to gel in with all kinds of processes) the demands for this are very high as well. It can be fitted in big and small plants to operate equally well in any condition. The distributor, or the header, of this kind of exchanger is a welded box which is located near the finned tube. It has small holes in it so that one can clean it out without screwing it open and removing the components. It has very low costs but high versatility so is able to meet all sorts of industry demands.

Pipe and Bend Configuration

This kind of air cooled heat exchanger is mostly used when one only has to work with fluids and not gases or hydrocarbons of any kinds. It can come in many different sizes so it can be installed in huge factories or small ones equally well. The header is simply a forged pipe which can be twisted to let the cooled liquid, mostly water or milk, out through the end. The advantage of this kind is that it has been designed to withstand liquids coming out of it at very high pressures. There is no inspection opening provided so it is highly suggested that people use it after they have purified and verified their liquid, especially if it is a product that has to be marketed. However, the welding on the cooled heat exchanger is brilliantly done and is made to withstand even the most hazardous material.

Thus, it is plain as day that in a number of factories and industries, air cooled heat exchangers are as important as the raw materials, especially when it comes to safety precautions and rules. There is a special kind of air cooled heat exchanger available for all factory settings and so, one can easily go out and purchase whatever will work best for their environment.

Air Cooled Heat Exchanger (Part II)

7.0 Design

a)      Tube bundle design

i)        A tube bundle shall be rigid, self contained and designed for handling as a complete assembly.

ii)      Provision is required to be made by vendor to accommodate thermal expansion of tubes.

iii)    All tubes are supported by vendor to prevent sagging or deformation of fins.

iv)    A hold-down member (tube keeper) is provided at each tube support, hold-down members are attached to side frame by bolting.

v)      Tubes of single pass cooler are sloped towards the outlet header.

vi)    Tubes of multiple pass coolers may not be sloped.

vii)  The exchanger may be designed for an internal steam out operation at the temperature / pressure specified by the process licensor.

b)     Heating coils

i)        Heating coils are provided to protect the process tube bundle against freeze up and are provided in the bundle separate from the process bundle.

ii)      Heating coils to cover the full width of process tube bundle.

iii)    Heating coils are normally single pass type.

c)      Headers

i)        Provisions are made in the design of header, to prevent excessive warpage of tube sheets and leakage at tube joints. Any alternative operating conditions including low process flow at low ambient air temperature, freezing of fluids in tubes, steamout, stoppage of fan due to power failure, any cyclic conditions must be included by the vendor in the analysis if specified by the designer.

ii)      When the fluid temperature differential between inlet of one tube pass and the outlet of adjacent tube pass is higher than 110degC then split header construction with ‘U’ tubes or other method of restraint relief shall be employed.

iii)    If the fluid temperature difference between inlet and outlet of multipass bundle exceed 110degC, the need of restraint relief shall be insisted.

iv)    The cover plate header designer shall permit removal of cover without disturbing header piping connections. This helps in providing access to tubes during maintenance and repairs.

v)      The bonnet header design shall permit removal of bonnet with minimum dismantling of header piping. This helps in access to the tubes during maintenance and repairs.

vi)    Plug header are equipped with threaded plug holes provided opposite to the ends of each tube for access. This helps in providing access to the tubes during maintenance and repairs without disturbing the header as well as piping.

d)     Nozzle and other connections

i)        All connection 1 ½” and larger shall be flanged

ii)      In hydrogen service all connections shall be flanged and slip on flange shall not be used.

iii)    Where design conditions require class 900 or higher flange rating, all connections shall be flanged.

e)      Maximum allowable moments and forces for nozzle and headers

i)        In corroded condition each nozzle shall be capable of withstanding the simultaneous application of the forces of the forces and moments as defined in Annexure A.

Annexure-A

ii)      The sum of nozzle on a single header will consist of components that do not exceed Mx of 4500 ft.lbs, My of 6000 ft.lbs, Mz of 3000 ft.lbs and Fx of 2250 lbs, Fy of 4500 lbs and Fz of 3750 lbs. The application of the forces and moments as per Annexure A will cause movement that will tend to reduce the loads to the values given above.

iii)    The total of all nozzle loads on one multi bundle bay shall not exceed 3 times allowed for a single header.

f)       Air side design

The environmental factors such as weather, terrain, adjacent building and equipment will influence the air flow and hence performance of an air cooled heat exchanger for fan dispersion angle refer figure 3.

g)      Drive arrangements

Refer figure 3 and 7 for typical drive arrangement for air cooled heat exchanger.

h)     Design loads

i)        Thermal forces shall include all forces due to partial or complete anchorage of piping or equipment, friction from sliding or rolling of equipment, and forces from expansion or contraction of structure.

ii)      Nozzle load shall include all forces and moment applied to the nozzle face including the dead weight of pipe, thermal forces and the weight of fluid in the piping.

i)          Mechanical Access facilities

i)        The number and location of header access platform interconnecting walkways and ladder shall be specified in enquiry specification during detailed engineering.

ii)      Maintenance platform shall be provided beneath each drive assembly for easy access to drive and for removal and replacement during maintenance of all drive components. The platform shall be provided all around the drive assembly.

iii)    Ladder, Railings, toe plates and safety chains with safety bolts etc. shall be provided for platform as per good engineering practice.

iv)    Header shall be provided with toe bone or knee railing on the side next to the exchanger.

8.0  Design Features of Air Cooled Heat Exchanger

Air cooler consist of tubes, header boxes, fan, motor and sometimes louvers. Tubes are all placed in number of horizontal layers and both ends of the tubes are welded in the rectangular header box. This is similar to tube sheet of conventional heat exchanger. The piping gets connected to nozzles of this header box. Typical drawing of above arrangement is attached here with (refer fig. 2, 5, 6) these header boxes are supported on steel frame. The fan is provided below the tube bundle in force draft arrangement. The fan is provided above tubes in induced draft arrangement.

Following different type of constructions are generally available:

a)         Singlepass Cooler.

b)         Multipass Cooler.

c)          U tube Coolers

In a single pass and multipass cooler with odd number of passes, the fluid enters from one end of the header box and leaves at the other end of the header box.

In multipass with even number of passes and ‘U’ tube, the fluid enters and leaves from the same end of the header box.

The following general design featured shall be taken into account from equipment layout/piping layout point of view.

8.1      The tube bundle has a provision to move in lateral direction + 6 mm or 13mm in one direction. This movement is required for accommodating piping header movement. In case additional movement is required due to piping, needs to be specified during enquiring stage. This is shown in figure 1.

8.2      The tube expands in longitudinal direction and normally a provision is made such that the inlet header side is a fixed side and tube expands in the other direction.

9.0  Consideration from Equipment Layout Point of View

9.1              This equipment requires smooth air flow for cooling purpose hence the location of the equipment should be such that it is not closely surrounded by equipment or structure which blocks the air flow path.

9.2              To give a better air flow, this is installed on the top of the pipe rack, or structure so that there is no obstruction to reduce air flow. At the same time by installing on top of the rack, the space on the ground can also be saved and the plant becomes more compact.

9.3              Normally tube bundle length is fixed based on the width of the piperack or structure so that the supporting legs of air cooler bundle comes on the main beams, which can simplify the pipe rack design. Also it is preferable to adjust piperack / structure longitudinal column spacing based on the width of the air cooler bundle so that legs of bundle straight away sit on top of the column. This may not be possible to adjust some times as each tube bundle may have varied width depending on service condition and adjusting piperack columns for different width may not be feasible from structural design and detailing point of view.

9.4              It is required to provide walkways between two sets of air coolers. This means say one cooler may consist of 10 bundles and other one of 5 bundles then walkways should be provided between, after tenth bundle and before starting of next five bundles. This walkway shall be minimum 1.5 to 2.0 m wide as this will be the only place at that elevation to store tools and parts during maintenance.

9.5              The air coolers on the piperack shall be located such a way that at least from one side the bundles are accessible with crane.

9.6              Air cooler should have access platform mounted on the air cooler structure at least on the operating side. Platform all around is better for maintenance.

9.7              Air coolers have motors hanging at the bottom of the cooler. It is required to provide access platform underneath the cooler for motor & for maintenance. This platform can be a localized also.

9.8              To access the air cooler platforms or motor maintenance platform, a regular staircase is required to be provided.

9.9              Inlet piping of air cooler has a symmetrical distribution and loops as explained later in this article. This is required to be supported hence either air cooler structural columns need to be extended upwards to support piping or piperack / structure columns. This data is required to be given very early in the project as it is to be considered in piperack design.

10.0  Consideration from Piping Point of View

The air coolers are mainly used where very large quantity of vapor is required to get condensed or very large quantity of gas/ liquid is required to be cooled. The application is very common in case of column overhead vapor condensation. Following points need to be taken care while laying air cooler piping.

10.1          Piping distribution to air cooler should be symmetrical from centre line of complete air cooler assembly.

The typical configuration of inlet piping is shown in Figure 8, 9, 10, 11.

10.2          In case of supply line having very low pressure, care shall be taken to keep no. of bends to minimum without sacrificing functional and stress requirement. Line sizing during the distribution should be sufficient, if required check with process department.

10.3          Length of each branch pipe for all bundles from its header shall be more or less same to keep pressure drop same and equal distribution of fluids to all bundles.

10.4          Inlet side header box shall be considered as a fixed point (in tube direction) for piping connection. But the bundle can move in transverse direction of tubes + 6 mm or if it is fixed at one edge then it can move by 13 mm in the other direction. This movement is required for piping header expansion compensation. If air cooler is required to be mounted in eccentric position i.e. to get 13 mm movement in one direction, vendor shall be informed early enough.

10.5          The transverse movement of bundle can occur only when piping connected to nozzles generate enough force to overcome friction at the bundle support point. That is why normally at the support point vendor provides S.S plate, PTFE plate or ball bearings to ease the movement.

10.6          The force due to thermal expansion of piping created on the bundle nozzle shall be less than the limits given by API 661.

10.7           While doing stress analysis, the following considerations shall be given.

10.7.1    It is ideal to simulate the complete air cooler with tubes, header boxes and support points in computer program. But most of the time it is difficult, then model air cooler bundle as a rigid element with total weight of bundle with supports and friction co-efficient depending on type of supports.

10.7.2    After modeling piping along with each bundle as explained above, the piping stress analysis to be carried out. During this analysis all the nozzles in longitudinal & transverse direction to be considered as rigid i.e. anchor. After the analysis, check the loading on each nozzle. If these loading are within the limits of API 661 there is no problem. By modeling the air cooler either as rigid element or as a normal equipment, with weight & support friction, the nozzle loads shown by computer in operating condition will be taking care of bundle movement. In case nozzle loads on some nozzles exceed API 661 limits, the configuration of such pipe needs to be modified to reduce nozzle loads.

10.7.3    In case it is difficult to model air cooler due to some reason, the following method should be adopted.

Consider all nozzles as anchor points and model complete piping system as usual. Now do the analysis & find out which all nozzle loads exceeds, the nozzle where load is exceeding the values of API 661, feed 1 mm nozzle movement to that nozzle and carry out analysis. This 1 mm movement shall be fed in the direction in which header will try to move the bundle. If it still does not meet go on adding movement of 1 mm & check till results are satisfactory. In the first case where nozzle is considered as anchor point, find out the difference between actual loads & API loads, that will tell whether the differential loading will allow bundle to move or not with friction factor on support point. Of course this is a very crude method of analysis and as far as possible should be avoided unless it is a very small air cooler and nozzle load is not governing the design.

10.7.4    The outlet piping when analyzed, the bundle movement due to inlet piping should be modeled if analysis for inlet & outlet is not done together. Again nozzle loading criteria for outlet piping to be met as per API 661.

Fig1A – Typical Air Cooler Arrangement

Fig 1B: Air Cooler Section

Fig 2: Typical Bay Arrangement

Fig 3: Fan Dispersion Angle

Fig 4: Typical Plenum Arrangements

Fig 5: Typical Construction of Tube bundles with Removable Cover Plate and Removable Bonnet Headers

Fig 6: Typical Construction of a Tube Bundle with Plug Headers

Fig 7: Typical Drive Arrangements

Fig 8: Air Cooler Inlet Piping – Various options

Fig 9: Air Cooler Outlet Piping – Various Options

Fig 10: Air Cooler Pigtail Configurations – Various Options

Fig 11: Air Cooler Pigtail Configurations – Various Options

Air Cooled Heat Exchanger (Part I)

1.0 Introduction to Air Cooled Heat Exchanger

This kind of heat exchanger are used in petrochemical and refineries to utilize the atmospheric air to cool the hydrocarbon, process and utility fluids by means of indirect heat transfer from fluid (within the tube) to be cooled by air being circulated by means of forces / induced draft fan. In order to increase the heat transfer area, fins are also attached to the periphery of tubes. These heat exchangers are generally designed, inspected and tested as per API661 standard.

These exchangers are similar to the radiator of a motor car. The air cooled heat exchangers are mainly used where the heat load is very high and conventional heat exchanger becomes extremely big with large water requirement. By using air cooled heat exchanger, water requirement reduces drastically and cooling tower size comes down. The air cooler are of very large size as the heat transfer co-efficient with air is very low. Due to the large size, they are mounted on top of the pipe rack to save space.

2.0  Types of Air Cooled Heat Exchanger

There are three types of air cooled heat exchanger:

a)         Forces Draft

b)         Induced Draft

c)         Natural Draft (used for applications like transformer oil cooling)

The outline sketch and components are as identified in figure 1A & B.

3.0  Definitions used for Air Cooled Heat Exchanger

The general terms used for air cooled heat exchangers are defined below:

a)      Bank

A bank is one or more bays including one or more items arranged on a continuous structure.

b)     Bare tube surface

Total area of the outside surface of the tubes in sq. meter.

c)      Bay

A bay is one or more tube bundle serviced by two or more fans and that include structure, plenum and other attendant equipment.

d)     Finned Surface

The finned surface of a tube is the total area of the outside surface of fins exposed to air.

e)      Forced Draft exchanger

This is the one designed with the tube bundles located in the discharge side of the fan.

f)       Induced Draft exchanger

This is the one designed with the tube bundles located on the suction side of the fan.

g)      Tube bundle

This is an assembly of headers, tubes and frames.

Refer figure 1A, 1B, 2, 3, 4, 5 and 6 to understand the above definition.

4.0 Content of Enquiry Documents (Special Requirements)

The enquiry documents shall specify any special requirements concerning location of airflow, any obstruction to airflow and other heat sources.

5.0  Vendors Responsibilties

The vendor’s proposal shall include the following:

a)      A proposal drawing showing major dimensions in plan, elevation, nozzle size and orientation

b)      The proposal shall state whether the vertically mounted electric motors are to be shaft up or shaft down.

c)      It should show the supporting arrangement of the tube bundle / plenum, fan and fan drive assembly.

d)     It should show the relation of the tube bundle part of the bay with respect to the plenum to depict the movement of the nozzle installed on inlet and outlet headers.

e)      It should show the platform and ladder for accessibility, operatibility and maintenance of fan, drive assembly and piping hooked up to the nozzles located on the inlet and outlet header.

f)       It should show the weight of components, part of fan and drive assembly to derive the lifting beams, monorail and hoist arrangement to be permanently installed for maintenance of such components.

g)      The supporting column shall be located such that it matches the supporting structure to house the air cooled heat exchanger e.g. pipe rack or building structure.

h)      Allowable nozzle loading standard or data must be furnished to meet the same during detailed engineering.

i)        The fixed point of the tube bundle shall be defined such that the inlet nozzles (hot fluid side) experience minimum movements in comparison to (cold fluid side) outlet nozzle to maintain the nozzle loading within allowable limits.

j)        In order to achieve the smooth movement of the tube bundle headers and nozzles over plenum, a friction between the tube bundle and plenum must be means of providing smooth surface such as Teflon pads, stainless steel plate, graphite pads or similar material which can withstand the system temperature and compressive load of component at support.

6.0 Approvers Responsibilities

The approver shall approve following information received from vendor :

1. Maximum and minimum design temperature.
2. Overall dimensions.
3. Dimension and location of supports.
4. Nozzle size, rating, facing, location, projection, allowable movements and loading on nozzle (forces and moments).
5. Weight of components for erection and maintenance.
6. Drive mounting details.
7. Screen platform and ladders.

The Use of Plate Heat Exchangers and Air to Water Heat Exchangers in the Air Conditioning Industry

Heat exchangers are devices specially created for efficiently transferring the heat from a liquid to another liquid over a hard surface. This heat transfer can be absorption or heat dissipation. Heat and cooling exchangers are found every day on all sorts of devices, from boilers, or furnaces, to refrigerators and air conditioning systems.

As a device for heat transfer, it is a purpose of the heat exchanger to transmit heat as efficiently as possible. This allows the selection of the ultimate tool, for example, when it arrives to saving energy by recuperating wasted heat and causing it to be useful. In the case of a misuse of energy or heat flux that is not recovered, a brazed plate exchanger redirects the hidden flow of heat into something that can be used.

Whether for heating, ventilation, air conditioning or cooling, the brazed plate heat exchangers are perfectly suited for all applications. In ventilation, air conditioning and cooling systems, brazed plate heat exchangers ensure clean air and a chilly breeze. The brazed plate heat and cooling exchangers are a piece of equipment preferred for the mechanical industry.



The heat brazed plate exchangers, along with the air to water heating and cooling exchangers are the basic components of any air conditioning system. Without them, this machine would be nothing more than a fan. Companies that manufacture air conditioners are entirely dependent on heating exchanger producers. This dependence reflects highly in the financial statements of the suppliers of heating plate exchangers, since the air conditioner industry has increased at a fast pace.

The heat plate exchangers are widely used for heating, cooling and even refrigeration. Heavy Industries that use this technique are the power plants, chemical and petrochemical, petroleum and refined petroleum, natural gas processing plants and waste water treatment.

Gaskets that connect the disks are the main weakness of this heat plate exchanger's frame. Depending on the speed of the fluid and corrosion, seals can begin to lose, after a period, after the downtime that require maintenance and replacement. Pressure drop in the heat and cooling exchanger is high, and this may require the purchase and operating costs and more efficient pumping system. Although the maintenance is easier for a plate exchanger, it can still become clogged. This leads to long periods of inactivity.

To make sure that your device is properly taken care of, you will need to clean it regularly. Remember that almost all deposits can be moved by chemical means. This cleaning should only be done by a professional, because the improper use of chemicals can damage the device. Also, mechanical removal uses a number of different techniques. There are special scrapping brushes that reach the tiniest corners of the device.

No matter how you choose to clean your heat exchanger, keep in mind that it is recommended to ask for an expert's help. Try and prevent fouling as much as possible.

Compact Plate Fin Heat Exchangers

A plate-fin is a variety of custom shell and tube heat exchangers design that utilizes a plated and finned chamber in order to move heat in between fluids. It is often classified as a compact exchanger of heat to emphasize its relatively high heat conversion surface area to quantity ratio. The plate-fin is widely used in several industries, like the aerospace business for its compact size and light-weight properties, as well as in cryogenics exactly where its ability to facilitate warmth transfer with little temperature differences is required.

Going Deeper Into Plate-Fin Custom Shell And Tube Heat Exchangers Design

A plate fin custom shell and tube heat exchangers design was actually developed by an Italian technician, Paolo Fruncillo. A plate-fin exchanger consists of layers of corrugated sheets divided via flat metal dishes, usually aluminum, to establish a number of finned chambers.

Separate cold and hot fluid streams circulation through alternating levels of the exchanger and are generally enclosed in the sides through bars at the sides. Heat is moved from one stream with the fin interface towards the separator plate and with the next set of fins to the adjacent fluid. The actual fins also serve to boost the structural integrity from the heat exchanger and allow this to withstand high demands while providing a long surface area for the exchange of heat.



A high level of flexibility is present within plate-fin custom shell and tube heat exchangers design as they can operate along with any blend of natural gas, water, as well as two-phase liquids. Heat transfer in between multiple process channels is also accommodated; having a variety of fin levels and types because different entry as well as exit points are readily available for each stream.

The main kinds of fins tend to be: plain, which make a reference to basic directly finned and triangular or even rectangular designs; herringbone, in which the fins are positioned sideways to produce a zig zag path; and serrated and perforated that refer to cuts as well as perforations in the fins to augment circulation distribution and enhance heat transfer.

The drawback to plate-fin custom shell and tube heat exchanger design is that fact that they are susceptible to fouling because of their compact flow pipes. They also can't be mechanically cleaned, as well as require other cleanup methods in addition to proper filtration to eliminate potential fouling streams.

Inside a plate-fin, the fins are often capable of being rearranged. This enables both liquids to result in cross counterflow, counterflow, cross flow or even parallel flow. When the fins were created properly, the actual plate-fin heat exchanger can work in ideal countercurrent arrangement.

The cost of a plate-fin custom shell and tube heat exchangers design is typically greater than conventional warmth exchangers due to a higher level associated with detail required throughout the manufacturing process. However, these types of costs can often be outweighed through the savings made by the added exchange of heat.

The Basics of Heat Exchangers

Heat exchangers are a staple in today's devices. They are not only present in the simplest of devices; exchangers have also found their use in big industries and machineries in the world today. They are basically devices found in some machines that enable it to transfer heat from one medium to another. They facilitate the efficient transfer of heat from one object to another.



Use of Heat Exchangers

One example of this is the radiators found in cars or air conditioners. What usually happens is that a heat source transfers water that will cool the engine through the exchanger. The exchanger will transfer heat from the water to air leaving the engine cooler.

Heat exchangers are widely used for the purposes of space heating air conditioning and even refrigeration. Heavy industries that also use this technology include power plants, chemical and petrochemical plants, oil and petroleum refineries, natural gas processors and sewage treatment facilities.

Types of Heat Exchange Flow

Heat exchangers can be classified into two types, mainly according to their flow arrangements. These are the parallel-flow and the counter-flow exchangers.

The parallel-flow exchange involves the two mediums going in the exchanger through the same side of the device. For example, two fluids will enter the exchanger at the same side and travel parallel each other for the whole process.

The counter-flow exchange, on the other hand, is the opposite of the first process. Here, fluids will enter the device from different ends and meet each other for the process of heat exchange. Many exchangers use this flow since it has been proven to be the more effective of the two processes because it can transfer more heat from the heating medium to the other. In this set-up, the mediums travel to one another and are then processed by the exchanger.

Traditionally, exchangers are designed in a way that the surface area between the two exchanging fluids is maximised whilst minimising the resistance to the exchange flow at the same time. Additional fins installed in either direction where the fluids enter can also enhance exchangers. These fins can add to the surface area of the exchangers whilst also helping control the flow of fluids during the exchange process.

Temperature during the Heat Exchange Process

Depending on the size of the exchanger, temperature will vary during the exchange process. The temperature will also vary according to the position of the device. But many industries that use exchangers almost always have their own defined mean temperature.

This temperature is usually defined in terms of the Log Mean Temperature Difference or the LMTD. Sometimes though the temperature is still hard to determine through the LMTD method, in this case, the NTU method is then used.

Types of Heat Exchangers

There are several types of heat exchanger used today. These include shell tube exchangers, plate exchangers, adiabatic wheel, plate fin, fluid exchangers, dynamic scraped surface, phase-change exchangers, HVAC air coils, spiral exchangers and the direct contact exchangers.

Company profile of PERFEX INTERNATIONAL

PERFEX INTERNATIONAL is an established manufacturing company specializes in Radiators, Charged Air Coolers, Heat Exchangers and Oil Coolers for power generation and other industries.

PERFEX INTERNATIONAL is the name that is synonymous with perfect heat transfer equipment and total solutions. Our key success factor is to establish strong partnership with our valued customers and deliver quality products & services at competitive prices without compromising our customer’s needs.

At PERFEX, we strongly believed that apart from quality products and reliability on delivery, we are committed and aim to meet and even exceed our customer’s expectation.

Services
 
Manufacturing and supply of:

• set mounted radiators
• Pulley driven radiators
• Motor driven radiators
• Remote oil cooler
• Change air cooler
• Shell & tubes heat exchangers
• Set mounted fuel coolers
• Air cooled heat exchangers
• Automotive radiators
• Condenser/evaporator coils
• Industrial fans with aluminum & plastic impellers
• Service & repair of all above products
• Technical Support

Consultation and providing technical solution

• Installation and commissioning
• Trouble-shooting
• Technical presentation, seminar and training

Content Us

PERFEX INTERNATIONAL PTE LTD

82, Tuas Ave 11, Singapore 639097 

Tel :  (65) 6863 1911

Fax :  (65) 6863 1511 

Profile on Ad-Meth Mech-Field Pte Ltd

Ad-Meth Mech-Field Pte Ltd

Refurbishment, hydrojetting, and maintenance services for heat exchangers and air fin coolers
Ad-Meth Mech-Field Pte Ltd was established in 1991 to provide the local petrochemical & process industry in Singapore with specialized mechanical fabrication, high pressure water jet cleaning, refurbishment and maintenance services for heat exchangers and air fin coolers.

Since then, we have expanded our business scope into the trading of tubes, fittings, provision of high and ultra high pressure water cleaning as well as process & mechanical design of heat exchanger.
Ad-meth design & fabricate heat exchangers with a full range of Low Temperature and Regular or Carbon Steel, Stainless Steel, Duplex, Incoloy, Nickel, Hastelloy and Clad Materials.

All units are designed, inspected and tested at our workshop, meeting the requirements of the ASME Code, and TEMA standards.

Our staff are capable, experienced and are fully committed to providing the best product quality and service to all our clients. Our close and amicable working relationship with our clients, vendors and contractors alike is testament to our technical competence and the confidence and trust with which we have garnered over the years.

At Ad-Meth Mech-Field Pte Ltd, we believe in working closely with our clients to achieve the best value with no compromise on safety, quality and the environment.A Leading Provider in Cleaning & Refurbishing Services for Heat Exchangers

Backed with more than 2 decades of experience and numerous safety awards, Ad-Meth is Singapore’s leading provider in cleaning & refurbishing services for heat exchangers and other equipment mechanical design and fabrication works.

Design, Fabrication, Retubing & Repair of Heat Exchanger

We have extensive experience in Mechanical Design & Fabrication, Retubing & Repair of Air Cooler, Heat Exchangers (Shell and Tube Bundle), U-Tube Bending, Machining and Drilling of Tubes Sheets and Baffle Plates, Welding Works and with pipes and flanges.

With in house capability for pressure vessel and heat exchanger design and analysis, all our fabricated Heat Exchangers & Air Fin Fan Cooler conforms to ASME codes and TEMA standards.

Contact us

Add: 38 Gul Circle Singapore 629573

Tel: +65 6268 0300

Fax: +65 6268 6765

Email: email@admeth.com

Profile on NEPTUNE Heat Exchangers Pte Ltd

The Company
A joint venture Company since 1992 between Singapore and UK partners catering to the International Shipping and Industrial markets where high quality but affordable air coolers and exchangers were in demand. Neptune Heat Exchangers (NHE) is now a major player & command a high market share due to our good workmanship, high quality product, affordable pricing & speed of production.

Site Inspection

Scope of Work
We manufacture all types of Charge Air Coolers, Shell & Tube Condensers & Heaters, Blast Air Coolers, Radiators, Oil Coolers etc for Marine & Industrial Engines & Machinery. We maintain a huge database of some 5000 drawings of all Air Coolers and Exchangers in order to respond quickly to our Customers need. In instances where we do not have the required measurements, our Company will despatch a technician to any Asian or European port or city at no cost to our Customer...

Stocks from Germany and Japan - meeting the most stringent requirements

Company Policy
Our products are quality assured & hydro tested and are certified by the relevant Classification Societies prior despatch from our factory. Over and above these checks we provide warranty against bad workmanship and defective materials.

We make sure you will be satisfied with our solutions to your problems.

Our high quality products are exported Worldwide and the regular repeat orders we received is proof of our Customers Satisfaction.

PRODUCTION

Our factory is located within the vicinity of major Shipyards & Port Area. We have a production team of skilled & experienced workers under supervision from our Production Manager. Modern Computerised NC machines are use in this precision work with support from computers to generate working and final drawings.

MARINE

Materials are all imported and meeting quality requirements of British & ASTM Standards. Air Coolers are made from 90/100 Cupro-Nickel Tubes, Hot-Rolled Naval Brass Plates & high quality Copper fins. Our Air Coolers are manufactured with new "Square" or "Block" Finned design which has:-

a) 25% more Cooling Surface Area & Improved Pressure Drop
b) Strong Resistance to Vibration & Elimination of Tube Sagging
c) Cleaner Air Flow Through Fins & Easier Maintenance.

However, to meet certain customer preferences we can also manufacture air coolers with round copper fins and aluminium brass tubes.

Heat Exchangers such as FW, LO, FO Coolers & Heaters, Crane Oil Coolers and Air Cond Evaporators using different materials and designs are regularly manufactured by us.

INDUSTRIAL

Besides Charge Air Cooler, we manufacture Blast Air Coolers, Radiatiors, Intercoolers, Heaters & Coolers for Power Plants, Refineries, Cement Plants, Mills, Factories, Desalination Plants etc. Materials such as Aluminium, Brass, Cupro-Nickel, Titanium, Stainless Steel as required by Clients can be offered.

Contact us

NEPTUNE HEAT EXCHANGERS PTE LTD

4 Penjuru Place, 2-8 Penjuru Tech Hub #01-19, Singapore 608782

Tel: (65) 6863 8272 Fax: (65) 6863 8273

If you are interested to know more of our products, or if you have any questions, please give us a call or e-mail us...

Albert Koh 

General Manager

Mobile - +65 9668 0672(24hrs)

albertkoh@nhe-exchangers.com