Wednesday, September 17, 2014

Ways for FRP cooling towers manufacturers to play around with design to suit needs of clients


FRP is an interesting material which allows manufacturers to play around with its shape and achieve desired results. Majority of the products are produced in conventional designs and profiles but it has adjustable mechanical properties which are leveraged by cooling tower manufacturers in Delhi.

To get into the details, most manufacturers use four types of reinforcement in FRP namely E-Glass, Aramid, S- Glass and Carbon. All these have different qualities like density, tensile strength, tensile modulus and % elongation to break- E Glass has the maximum density (0.094 lbs/in3), S Glass has maximum Tensile strength (665,000 psi) and E Glass has more tensile modulus 10.5 (106 psi) and elongation to break (4.8%). For these reasons E Glass is the most commonly used variant as reinforcement in FRP cooling towers. 

Further there are Two main Types of Reinforcement – continuous strand mat and continuous strand roving. The most economic style is continuous strand mat where a resin is used as a binder for glass fibres. Layered with roving, these are mats of intertwined glass fibres and the ratio of mat to roving is important for manufacturers as it decides the longitudinal and transverse strengths.  In continuous strand roving- the key is number of roving used and their location as both these affect the product’s performance. Roving is the one behind tensile strength of structure and its pultrusion can make the reinforcement look closer to the surface of product. Resins are the veils used on surface of the product to distance the reinforcement which otherwise influences corrosion resistance etc.  Commonly used materials for resins are polyster, epoxy and vinylsester. Epoxy is the one which is more popular and add considerable strength to the structure and commonly are teamed with E Glass.

Cooling tower manufacturers play around with FRP to suit their needs and add different chemicals to augment its properties like aluminium silicate for finish and insulation, calcium carbonate for opacity and cost effectiveness etc. the material offers lot of opportunities and its flexibility makes it the most popular material for cooling tower construction.

Tuesday, September 9, 2014

Reasons why FRP cooling towers are clients’ and manufacturers’ favourite

When we see cooling towers in Delhi, we notice that the most commonly used material is the FRP. This material is relatively new as compared to others like wood, steel, concrete etc. Earlier FRP was used as a supporting secondary material implying use in pipes, fan stacks etc. rather than the primary one which is visible to the eyes and therefore people have this misconception that Fibre reinforced polymer is a new material- well it has been around for more than 30 years in cooling towers.

With number of benefits of FRP like sustainability in adverse weather conditions, flexibility in design, cost effectiveness and ease of installation etc. the material has been rapid growth in applications in the industry and has become one of the favourite materials. This has also led to flourishing of number of FRP cooling tower manufacturersin Delhi region. The key is to find a genuine manufacturer who designs compact and space saving cooling towers as these seems to be in demand from the clients. The flexibility of shape with this material is far more than comparable ones like wood, steel etc. it allows the designer to achieve better aesthetics with the same buckling strength. The material has inherent qualities suitable for a weather resistant tower like moisture, corrosion resistance etc. and also requires less maintenance. Areas where there is high wind load, FRP offers better resistance than other alternatives.

Many view FRP as cost effective but one should understand that their initial costs are comparable to others; it is over period of time that this material requires low maintenance, less service, rare replacement, less laborious installation & transportation etc. The industries also experience lower number of downtime due to low maintenance requirements which again is beneficial. Other benefit is it is environment friendly as has no impurities that can percolate into water being cooled. The noise emissions can also be significantly reduced with intelligent designing of structures with FRP.  One can also see increasing use of pultruded FRP towers especially in western countries like US etc. 

Thus we see that growing popularity of FRPcooling towers can be attributed to its various beneficial properties and the liberty it gives cooling tower manufacturers to play around with shape and come up with attractive designs. Some genuine manufacturers are able to produce excellent products with FRP which might have high initial cost but over the time they give better returns as they need low maintenance compared to others.

Thursday, July 31, 2014

Intelligent addition to Cooling Towers resulting in huge power savings- PVC fills

PVC fill in cooling tower is perforated material has small corrugations which results in some tensions on the surface and this aids in containing the static air. This static air is responsible for keeping the water flowing from top to bottom of cooling tower for a longer period, which implies that water is cooled more. Since the cooling is more, this results in a more efficient tower.Another quality of PVC fill is that it is self- extinguishing which reduces the risk of spread in case of fire. This is a major risk for towers in an industrial set up with multiple machineries, especially in hot temperatures like in Delhi. 


As cooling tower manufacturers and design teams try to increase effectiveness of towers by playing with structure and material, the concept of fills come in. Fills are nothing but medium added in the tower which increases the contact surface and time between air and water which makes the evaporative process more effective. Let us understand why this happens- basic mechanism in a cooling tower is the heat exchange between falling water and air passing through it and this exchange is affected by 3 main factors- surface area, amount of time this interaction remains and turbulence or perforation in running water which defines how well they get mixed. 

Different materials can be used for fill by the manufacturer depending on requirement of the client as different materials offer different propositions and selection should be made considering factors like amount of heat, quality of water, horse power etc. Different clients have different needs depending on the purpose like some need to address high corrosion, high UV exposure, water clogging due to dirty water, risk of fire spread, high airborne contamination, bacteria, expensive installation due to high labor costs etc. Thus there are different materials used for fill like stainless steel, PVC etc. PVC fills are most popular given their advantages like lightweight, easy to install, good heat transfer properties etc

PVC Fills in towers need replacement and maintenance too as over the time due to usage; it leads to clogging with dirty water, risk of structure coming down due to weather- high humidity or heat etc. It is advisable to replace the fill at appropriate time as thermal performance of the tower is highly affected also making it efficient reducing the cost of operation. This reduced operating cost can be measured by reduction in fan power consumption in definite terms.


Thus PVC fills are an amazing accessory to add to the effectiveness of cooling towers without going overboard with expenses and the savings are quite attractive as a result of improved efficiency of the towers. This is shown by much lower power requirement for pumping.