Double twist stranders

GCREurodraw has more than 30 years of experience in the design and construction of plants and machinery for the production of strand and rope for every possible application.

GCR Eurodraw has developed technology in two sectors essentially:

The first covers a complete range of double-twist machines and plants for the production of steel cord to reinforce tires.

The second includes double-twist, skip and tubular machines for the production of strands and ropes made of bare, galvanized or stainless steel wires.

Furthermore, GCR Eurodraw has developed machines for the production of flexible shafts, flexible shafts with a metal and fabric wrap for screw drives; as well as special ropes to meet specific customer's requirements, with particular characteristics of resistance and fatigue, that are mainly used in the automotive industry.

And, last but not least, GCR Eurodraw offers tubular closing machines for the production of wire rope; and high productivity plants for the production of P.C. strand for the construction industry, with GCR Eurodraw skip stranders.

Overall, GCR Eurodraw offers a wide range of machinery that covers most of the requirements of the main producers of strand and rope. The only, self-imposed limitation is the maximum diameter of the finished product, which does not exceed 30 mm.

Some of the most interesting developments pursued by GCR Eurodraw have centered on continuing research into the principle of the double twist; not only for production of more or less complex strands but also, through indirect cabling, for production of wire ropes assembled with different layers of wires and/or strands.

This has resulted in double-twist machines that assure extremely high productivity with improved resistance to fatigue; that are, in fact, far superior to results obtained with classic tubular machines.

DOUBLE TWIST STRANDER range to produce steel cord includes:

DT2: “in – out” stranding machine with two inner spools and two external spools for production 1x2; 1x3; 2+1; 2+2, 1+6; standard, open, ST and HT.

DT3: “in – out” stranding machine type with three inner spools and up to four outer spools for production: 1x2; 1x3; 1x4; 2+1; 2+2; 2+3; 3+2; 4+3; 4x4HE; 3x7HE;  standard, open, ST and HT.

DTU: “out-in” type buncher for production of 1x4; 1x5; 1x7; 1x12 ST and HT ; 1x19 ST strands and cord.

DTS: “in-out-in” type buncher, for production 2+7; 3+9; 3+6  ST and HT cords.

DTA: “in-out-in” type cabling machine, for production 7x3; 7x4; 7x7; 7x19; 3+9+15; 1x19; 1x27; ST and HT cords.

Pay-off spools used on GCR machines vary depending on customer requirements, ranging from 190 to 400 mm flange diameter and weighing 20 to 140 kg.

Production speeds of GCR machines are among the highest available on the market; while at the same time they are, for all practical purposes, absolutely silent during operation.

Specific solutions have been adopted for tensioning/back pull of the filament and core pay-off wires or strands and for passage of the twists at deviation points of the wires/strands and their contact with the machine organs.

GCR machines offer numerous adjustment possibilities to obtain a product with very specific characteristics (diameter, lay, linearity, twists, flare, break elongation, elongation to fixed load, elongation stiffness, etc.) that, in particular, are required by every producer of radial tires.

The range of machines for production of steel cord also includes wrapping machines for laying of the spiral wrap on the finished cord construction; more precisely:

MV1: wrapping machine for cord constructions with diameters of 0.60 to 1.20 mm

MV2: wrapping machine for cord constructions with diameters of 1.00 to 4.00 mm.

DOUBLE TWIST machines for production of strands and ropes made of bare, galvanized or stainless steel wires.

DTUR: “out-in” type buncher with free catenary  for production of strands and ropes 1x7; 1x12; 1+6+12; 1+9+9; 1+6+(6+6); 1x25; 1x 36; Seale /Warrington; Filler strands etc. (for take-up spools with diameters of 250 to 500 mm).

DTUF: “out-in” type buncher with bow, for production of strands and ropes 1x7; 1x12; 1+6+12; 1+9+9; 1+6+(6+6); 1x25, 1x36;  Seale /Warrington; Filler strands etc. (for take-up spools with diameters of 400 to 1250 mm)

DTSR: “in-out-in” cabling machine with free catenary, for production of counter-layers strands and ropes 3+9; (1+6)+12 SZ; etc. (for take-up spools with diameters of 250 to 500 mm)

DTSF: “in-out-in” cabling machine with bows, for production counter-layers strands and ropes type 3+9; (1+6)+12 SZ; (for take-up spools with diameters of 500 to 1250 mm)

DTSFS: special double-twist “in-out-in” type cabling machine with bows, for production of  multi-layer flexible shafts. This range of special machine is supplied with wrapping machines to apply a metal wrap on the shaft with cotton filling.

DTAR: “in-out-in” type cabling machine with free catenary, for production of cables 6x7+FC; 6x7+IWRC; 6x19FC; 6x19IWRC; 6x19Filler ;6x19 Seale /Warrington; 8x19 +FC; 8x19 +IWRC; 8x19Filler ;8x19 Seale /Warrington; (1x4 + 8x7+8x7) rotation resistant, etc. (for take-up spools with diameters of 350 to 500 mm)

DTAF: “in-out-in” type cabling machine with bows, for production of cables 6x7+FC; 6x7+IWRC; 6x19FC; 6x19IWRC; 6x19Filler ;6x19 Seale /Warrington; 8x19 +FC; 8x19 +IWRC; 8x19Filler ;8x19 Seale /Warrington; (1x4 +8x7+8x7) rotation resistant, etc. (for take-up spools with diameters of 500 to 1250 mm)

Here too, pay-off spools used on GCR machines vary depending on Customer requirements and can range from 250 to 800 mm flange diameter and weight from 30 to 1000 Kg. Production speeds are among the highest available on the market. Similar solutions have been adopted for tensioning/back pull of the filament and core pay-off wires and strands and for passage of the twists at the deviation points of the wires/strands and their contact with the machine organs.

This range of machines is offered with the option of applying electromagnetic brakes, with dancer and sensor adjustment, or direct sensor readout of the pay-off pull. And these machines too are designed with multiple adjustment possibilities, to obtain products with the specific characteristics required by every user.

The machines can also be supplied with special pay-offs for textile cores and specially designed heads for production of compact ropes. All the machines are driven A.C. motors supplied by vectorial frequency inverters, with  digital synchronizations of the various motors installed. PLC or microprocessors for management of the functions and visualization of the operating parameters are an integral part of the electrical/electronic equipment.