Many properties of textile materials vary considerably with moisture regain – the ratio of the moisture to the bone-dry weight of the material expressed as a percentage. In this interview, Sujeeth Pai, Director of Sales and Service for Danfoss Drives in India, explains the effect of relative humidity (RH) on various textile manufacturing processes and importance of air compressors in maintaining air quality.
Why maintaining air quality in a textile unit is important?
The atmospheric conditions with respect to temperature and relative humidity play a very important role in the manufacturing process of textile yarns and fabrics. The properties like dimensions, weight, tensile strength, elastic recovery, electrical resistance, rigidity etc. of all textile fibres whether natural or synthetic are influenced by moisture regain.
Moisture regain is the ratio of the moisture to the bone-dry weight of the material expressed as a percentage. Many properties of textile materials vary considerably with moisture regain. This in turn is affected by the ambient Relative Humidity (RH) and temperature. Ideal humidity levels increase the strength of the fibre, lowers static electricity and heat levels by evaporation and settles the fluff and dust in the air. From cotton to yarn to weaving, each process requires different RH levels and the same applies to different fibres.
Similarly, compressed air is a key utility in the textile industry for both natural & man-made textiles. Compressed air is required at every stage of manufacturing. Large volumes of air are required by integrated cotton textile industries having Airjet Looms as well as in the polyester yarn industries. Moreover, compressed air is a very critical requirement in the POY valued added segment such as texturing.
What type of solutions are offered by your company for maintaining air quality?
Danfoss offers optimum process control through VFD solutions for supply & return air fans along with air-washer based on monitoring relative humidity & temperature control. Maintaining accurate relative humidity has a direct impact on the properties of textiles, such as tensile strength, elasticity, fibre diameter and friction. Furthermore, this can help save up to 20% energy cost on fans & water injection pumps. By maintaining relative humidity levels, the occurrence of static discharge which can adversely impact production output & maintenance down-time, can be eliminated.
Air compressors tend to have lower part-load efficiencies & high unload power. This presents textile industries with an opportunity to reduce energy cost on compressed air by 10% to 30%. Danfoss’s Customized VFD Solution for air compressors make energy savings possible. An added advantage is it helps in reducing air leakages and maintains accurate discharge pressure within +/- 0.1 bar which is important for value added processes.
What should be the parameters to select the right systems for maintaining air quality in a textile unit?
Various parameters like inlet air temperature & relative humidity, the type of process such as spinning, weaving, texturing etc., type of fabric, heat dissipated by the machines and so on, play a role in deciding the optimal air quality for textile unit. Once these factors are adhered to, one can maximise product weights, improve quality and increase machine speeds. On the flip side, if any of the mentioned considerations fall short, it could result in loss of production, damage machinery and harm staff.
Could you please highlight on some of new systems/products you are developing for improving air quality?
New generation of VFD solutions for humidification & air compressor applications offer capabilities in condition-based monitoring for early detection and planned maintenance of events like motor winding insulation failure, changes in load envelope due to clogging of air filter in a compressor or bearing failure resulting in higher vibrations. The drives are motor type independent and offer the possibility to use the same VFD models for various motor technologies including PM Motors & Synchronous Reluctance Motors. Integrated remote monitoring capabilities with Cloud interface will ensure quick response, easier access to information & accurate resolution in case of failures to increase machine uptime.
What are the emerging trends in air engineering systems with respect to their usage in textile units?
In the recent times, some of the few important emerging trends in air engineering systems for textile units include space optimization, power saving, improving energy efficiency and remote monitoring. Danfoss Energy Efficient VFD solutions come with high power density and smallest footprint complying to IE2 efficiency levels as per Eco Design Directive EN – 50598.