Guarantee for a quality carpet

A carpet is the guarantee of a decorative floor soft to the touch and sound + heat-insulated. It is composed of fibers produced from different ways ; which generates a wide range of prices. The carpet is an excellent floor covering in bedrooms, living rooms as well as passing areas such as corridors and stairs.

The yarn quality importance 

Single or assembled twisted yarns (BCF or Spun) are very often used when manufacturing woven and tufted wall to wall carpets because they allow numerous technical and above all design possibilities: it allows increasing the thickness of a yarn, gather several yarns of different natures, combine yarns of several colours or yarns with graduated dyeing affinities.

In general, these yarns are processed in a special way, that is to say the heat-setting, in order to develop the volume of the yarns and to make sure that the new properties obtained from the twisting remain permanent. Twist is set at a high temperature in autoclave or in a continuous process.

These treatments require a very high stringency in the procedure. A heat-set yarn in a wall to wall carpet is a guarantee that the velvet aspect will last because it reinforces its resistance to upsetting deformation and to plunger puncture, its resistance to wear, its dyeing affinity, its dimensional stability and its design. The yarn tips are "individualized" on the surface, which gives the velvet a particular grained aspect.

SUPERBA’s solution

From a quality point of view, SUPERBA has developed its equipment for saturated steam continuous heat setting of carpet yarns under pressure. The overheated steam and the hot air are synonyms of high temperature treatment with existence of air. This can result in oxidizing the fibers, bleeding of colouring agents if the yarns are dyed, dehydration and yellowing (wool) and destruction of oiling. However, numerous handlings mean high costs for heat setting in autoclave because of the labour force and the consumption of required energy. Yarn wastes are also quite important.

SUPERBA's carpet yarn continuous heat-setting equipment sets any kind of fibers used to manufacture wall-to-wall carpet: synthetic fibers (polyamide, acrylic, polyester, polypropylene…), natural fibers (wool) and various blends. Heat-set yarns are used to manufacture a lot of different velvet structures of wall-to-wall carpets, ranging from traditional velvet to Shag and Saxony velvet.

The heat-setting of carpet yarns is a necessary process if you want to obtain a high quality woven or tufted carpet.

The process - the quality guaranteed with steam

For processing carpet yarns, SUPERBA uses a patented heat-setting tunnel to set the yarn twist and frieze in a continuous process, without tension, at high temperature and in a saturated environment. The temperature ranges, combined with the saturated steam environment furthermore allow a perfectly gentle treatment of the yarns and prevent any possible oxidation. 

        Non heat set                           Heat set               

Heat-setting in saturated steam affords numerous advantages :

• Improvement of the synthetic yarn dyeing affinity by modification of the yarns,

• Tension release in the yarn twist levels,

• Unrestrained development of yarn bulk in order to obtain better covering rate in the 
  carpet,

• Possibility to associate yarns of different nature or colours,

• Programmable heat-setting temperature depending on the nature of the used yarn

A tunnel to maintain the pressure

On TVP3 (or previous TVP/2S) carpet heat-setting lines, SUPERBA uses a patented heat-setting process to continuously set, without any tension, at high temperatures and in a saturated steam field, the yarn twist and frieze.

The heat-setting tunnel patented by SUPERBA comprises 3 main parts :

• An entrance area, with a tightening head

• A central area, which length is between 9 to 18 meters depending on the materials being processed by the user,

• An exit area, with a tightening head.

The tightening heads serve as locks, since the material can enter and exit without allowing steam to escape from the tunnel. The steam pressure can reach 4 bars i.e. approx. 150°C. The saturated steam pressure is computer-controlled  and is in relation to the setting temperature, with a precision of +/- 0.3°C (steady state)

Description of the line & running principle :

See end of this section for other layout possibility

The heat-setting line is continuously fed by a RAT3 creel (1) equipped with both operating and reserve bobbins. Each yarn is individually controlled by an electronic motion detector set up on the feeding creel.

Creel for bobbins 

The yarn bundle formed by 24, 36, 48 or 60 ends passes through the PRE/3 pre-feeder (2) then is laid down without any tension in oval parallel coils by a DAV/3 coiling head (3), on an endless perforated stainless steel conveyor band(4).

 

The yarn layer is first treated inside the HEP/3 (5) pre-steamer. At the contact of the dynamic steam under atmospheric pressure (T° about 100°C) the fibres freely shrink giving to the yarn its ideal and regular bulk over all the laying.

HEP3 – pre-steamer at atmospheric pressure

Then the yarn layer goes through a RTV/3 cooling device (6) before entering the TVP3 heat-setting tunnel under pressure (7), composed of two cooling chambers, inlet and oulet which can be equipped with a TCC (turbo cooling), and one heat-setting chamber of 9 to 18 meters long. The inlet and oulet tightness of the tunnel is guaranteed by two TEP3 tightening heads and equipped with rollers of special high tenacity rubber. The optimum, constant and regular pressure between the tightening rollers is achieved through pneumatic jacks and PLC controlled, allowing a great flexibility of use.

TEP3 – pneumatic tightening head   

In the heat-setting chamber (7), with pure saturated steam under pressure at high temperature (up to 150°C), the yarn undergoes a thermic shock that definitively sets the fibres and yarns crimp, twist and molecular structure. Moreover, the use of pure saturated steam (without air) has the advantage of eliminating any risk of fibre oxidation and dehydration, encountered with other treatment fluids. A CBS/3 steam circulation blower system forces the steam passage through the yarn layer to ensure a uniform and homogeneous treatment in the laying.

The heat-setting temperature can be programmed with an accuracy of +/-0.3°C (steady state), up to 150°C depending on the yarn quality and type.

The heat-setting time can be adjusted by means of the conveyor band speed for each type of yarn in order to get the optimum quality.

TVP3 – heat-setting line                            TVP3- Control-panel (panel at line outlet)

A powerful computerized central unit with a large colour touch screen display automates and controls the running of the TVP/3 line. All the treatment parameters are centralized and memorized. An unlimited number of process recipes is available, ensuring absolute treatment reproducibility with no human interference. It controls the output, supervises the running of all the elements on the line and takes action whenever needed. Advanced functions such as history files, downtime reports, efficiency forecast calculation or maintenance manager are included ensuring traceability for a maximal quality; for a higher level of control, the system can be connected to PLANT-TRACK, our supervision software

 
TVP3 – Control panel : main desk                                    Screen shots from TVP3 control system

The heat-setting yarn layer goes through a STV/3 dryer (8) and a RTV/3 cooling device (9) before being unwound on the back frame (10) and stocked in a MAT/3 accumulator (11).

 
MAT3 – High capacity yarn accumulator

The yarns are separated, and then wound around conical or cylindrical bobbins on a B401 automatic doffing winder (12). The accumulator is used as a buffer between the heat-setting line and the winder, thus avoiding the line stoppage during the doffing on the winder.

TVP3 : a different layout possibility 

Configuration with creel and winder on the side (Note that in this configuration, one operator is able to look at line entry and exit and run the line from one central location )

1. ASD automatic splicing device (13): inserted between the MAT/3 accumulator and the B401 winder, ASD enables quick & reliable splicing of the complete bundle in one single operation thus increasing the process efficiency.

48 ands automatic splicing device

2. MF/4 friezing machine (17) : production at a reduced cost of frieze or textured yarns combined with the heat-setting operation

MF4 60 ends friezing machine

3. MCD Dyeing machine: creation of fancy yarns, space dyed yarns with long, short spots or solid colour, etc… combined with the heat-setting operation

6 colours MCD machine with CDM module in front