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Showing all 3 results

Spiral Strands

Description

Spiral Strands are assembly of two or more layers of round wires held helically around a centre usually of a single round wire. The wires are generally laid in opposite direction at different layers which is known as contra lay arrangement.

Direction of lay

The outer layer of wires in spiral strands are of right hand lay unless mentioned otherwise by the customers.

Protection from corrosion

The wires have galvanized coated surface finish. If specially called for ; the wires can be given additional protection against corrosion in the inner payers of the strands with a compatible filling of an active pigment(inorganic zinc paint) that remains like a paste. The dosing of the inner filling is such that it does not emerge from the strands while in use.

Tensile grade

The Spiral Strands are generally supplied in 1570 grade & 1770 grade. However, strands with lower grades can also be supplied.

Construction

Generally the Strands of following construction are commonly used. However, tailor-made designs to suit consultants’/contractors’ requirements can also be taken up.

  • 1×7(6-1)
  • 1×19 (12: 6-1)
  • 1×37 (18: 12: 6-1)
  • 1×61 (24: 18: 12:6-1)
  • 1×91(30:24: 18: 12:6-1)
  • 1×127(36:30:24: 18: 12:6-1)

Pre-stretching

Spiral Strands are pre-stretched under controlled conditions.

End Fittings

Spiral Strands are supplied with end fittings having desired lengths within the specified tolerances and is ready to install condition as per the requirements.

Minimum Breaking Force and Mass
Nominal Diameter Metallic Area Mass (Approx) Minimum Breaking Force
1570 N/mm2 1770 N/mm2
mm inch mm2 kg/m lb/ft kN 1000lb kN 1000lb
Construction 1×19
11 71/16 70.0 0.587 0.394 99.9 22.5 113 25.3
13 1/2 98.8 0.820 0.551 140 31.4 157 35.4
14.5 9/16 123 1.02 0.685 174 39.0 196 44.0
16 5/8 150 1.24 0.834 211 47.5 238 53.6
19 3/4 211 1.756 1.18 298 67.0 336 75.5
Construction 1×37
22 7/8 282 2.34 1.57 390 87.6 439 98.8
26 1 394 3.27 2.20 544 122 614 138
29 11/8 490 4.07 2.73 677 152 763 172
32 11/4 597 4.95 3.33 824 185 930 209
35 1 3/8 714 5.93 3.98 986 222
38 1 1/2 842 6.98 4.69 1160 261
42 1 5/8 1030 8.53 5.73 1420 319
Construction 1×61
20 233 1.93 1.30 322 72.3 363 81.5
22 7/8 282 2.34 1.57 389 87.5 439 98.6
26 1 393 3.27 2.19 544 122 613 138
29 1 1/8 489 4.06 2.73 676 152 762 171
32 1 1/4 596 4.95 3.32 823 185 928 209
35 1 3/8 713 5.92 3.98 985 221 1110 250
38 1 1/2 840 6.98 4.69 1160 261 1310 294
42 1 5/8 1030 8.52 6.73 1420 319
45 1 3/4 1180 9.78 6.57 1630 366
48 1 7/8 1340 11.1 7.48 1850 416
50 1450 12.1 8.11 2010 452
51 2 1510 12.6 8.44 2090 470
52 1570 13.1 8.78 2170 489
54 2 1/8 1700 14.1 9.46 2340 527

*  Special requirements on breaking forces can also be met.
*  Spiral Strands may be provided conforming to various relevant national and international standards to suit customer needs.
*  Spiral Strands can also be provided in sizes and constructions not included in the tables of this brochure.

Locked Coil Wire Ropes

Locked Coil Wire Ropes are manufactures from steel throughout, being built up by laying series of concentric; layers of shaped wires or a combination of round and shaped wires over a core made with round wires. The term ‘Locked Coil’ is derived from the fact that the wires of the outer layer and some of the wires of the inner layers are so designed to have a special shape so that they remain interlocked with one another. Full Locked Type construction which is more common in structural projects has an outer wire covering of ‘Z’ shaped wires which fir one to another; each wire being held in position by the adjacent wires.

Direction of lay

The wires of the outer layer in a Locked Coil Wire Rope are laid in right hand direction unless requested otherwise by the customer. The wires of the next inner layer below the top layer are laid in opposite direction. The wires of the subsequent inner layers are laid same or opposite direction as per the requirement of design.

Protection from corrosion

All Locked Coil Wire Ropes are adequately lubricated both internally and externally for protection against corrosion. If specially called for; the inner layers can be lubricated with a compatible filling of an active pigment (inorganic zinc paint) that remains like a paste. The dosing of the inner filling is such that id doesnot come out during use. The surface finish of the wires are either bright or drawn galvanized. The zinc coating for the round wires conform to international standards. The zinc coating on the shaped wires are maintained as per requirement.

Tensile Grade

In order to achieve the desired breaking force of Locked Coil Wire Ropes an appropriate combination of tensile grades is used for shaped and round wires.

Construction

The arrangement of wires in the ropes are as per Usha Martin’s standard design. A construction having multiple layers of shaped wires can be manufactured. However, Locked Coil Wire Ropes of special construction can be designed as per the requirement of the customer.

Pre-stretching

Locked Coil Wire Ropes are pre stretched under controlled conditions.

End Fittings

Locked Coil Wire Ropes are supplied with end fittings having desired lengths within the specified tolerance and in ready to install condition as per the requirements.

Minimum Breaking Force and Mass
Nominal Diameter Metallic Area Mass (Approx) Minimum Breaking Force
1370 N/mm2 1470 N/mm2 1570 N/mm2
mm inch mm2 kg/m lb/ft kN 1000lb kN 1000lb kN 1000lb
Center of Round Wires and 1 Layer of Shaped Wires
20 254 2.16 1.45 321 72.2 344 77.3 368 82.7
22 7/8 308 2.61 1.75 388 87.2 416 93.5 445 100
25 398 3.37 2.27 501 113 538 121 574 129
26 1 430 3.65 2.45 542 122 582 131 601 140
28 499 4.23 2.84 629 141 674 152 720 162
29 1 1/8 535 4.54 3.05 674 152 723 163 773 174
30 572 4.86 3.27 722 162 774 174 827 186
32 1 1/4 651 5.53 3.72 821 185 881 198 941 212
34 735 6.25 4.20 927 208 994 224 1060 239
35 1 3/8/ 779 6.62 4.45 982 221 1050 237 1130 253
36 824 7.00 4.70 1040 234 1120 251 1190 268
38 1 1/8 919 7.80 5.24 1160 260 1240 279 1330 298
40 1018 8.65 5.81 1280 288 1380 309 1470 330
Center of Round Wires and 2 Layer of Shaped Wires
25 412 3.50 2.35 520 117 558 125 596 134
26 1 446 3.79 2.55 562 126 603 136 644 145
28 517 4.40 2.95 652 147 700 157 747 168
29 1 1/8 555 4.72 3.16 699 157 750 169 801 180
32 1/1/4 676 5.74 3.85 851 191 914 205 976 219
35 1 3/8 808 6.87 4.61 1020 229 1090 246 1170 262
38 1 1/2 953 8.10 5.44 1200 270 1290 290 1380 309
40 1060 8.97 6.02 1330 299 1430 321 1520 343
42 15/8 1160 9.89 6.64 1470 330 1570 354 1680 378
45 1 3/4 1340 11.40 7.63 1680 379 1810 406 1930 434
48 17/8 1520 12.9 8.68 1920 431 2060 462 2200 494
49 1580 13.5 9.04 2000 449 2140 482 2290 514
50 1650 14.0 9.42 2080 467 2230 501 2380 536

*  Special requirements on breaking forces can also be met.
*  Spiral Strands may be provided conforming to various relevant national and international standards to suit customer needs.
*  Spiral Strands can also be provided in sizes and constructions not included in the tables of this brochure.