Transmission chain

steelin Nebulite®round

Overview
The Wear Resistant Round Link Chain is a mining/industrial chain engineered for enhanced wear resistance and tailored mechanical performance. It is available with three surface/heat treatment options to match application requirements: Low Temperature Tempering (LTT), Quenching Only (QO) and Carbonitriding (C-N).

Types of wear-resistant chains

• LTT (Low Temperature Tempering) — G90: Tempering below the A1 temperature to raise breaking load and maintain moderate hardness while retaining higher elongation. Hardness: 40–42 HRC (~390 HB). Elongation: ~14%.
• QO (Quenching Only) — G60: Quenching without tempering (temperature above AC3) to increase surface hardness with reduced elongation and some reduction in breaking load. Hardness: 45–47 HRC (~450 HB). Elongation: ~10%.
• C-N (Carbonitriding) — G40: Carbonitriding creates a hard surface shell (depth up to ~15% of chain diameter) with surface hardness up to ~64 HRC (~800 HV) and a tougher, more ductile core that preserves limited elongation. Relative elongation: ~1–3.5%.

Table: Chain dimensions (d x p) and weights
Header: Chain Size d x p (mm) | Diameter d (mm) | Pitch P (mm) | Inside Width b1 min. (mm) | Outside Width b2 max. (mm) | Weight (kg/m)
14 x 50 | d = 14 ±0.4 | P = 50 ±0.5 | b1 = 17 | b2 = 48 | 4.0
18 x 64 | d = 18 ±0.5 | P = 64 ±0.5 | b1 = 21 | b2 = 60 | 6.6
19 x 64.5 | d = 19 ±0.6 | P = 64.5 ±0.6 | b1 = 22 | b2 = 63 | 7.4
22 x 86 | d = 22 ±0.7 | P = 86 ±0.9 | b1 = 26 | b2 = 73 | 9.5
24 x 86 | d = 24 ±0.7 | P = 86 ±0.9 | b1 = 28 | b2 = 79 | 11.6
24 x 87.5 | d = 24 ±0.7 | P = 87.5 ±0.9 | b1 = 28 | b2 = 79 | 11.5
26 x 92 | d = 26 ±0.8 | P = 92 ±0.9 | b1 = 30 | b2 = 85 | 13.7
30 x 108 | d = 30 ±0.9 | P = 108 ±1.1 | b1 = 34 | b2 = 97 | 18.0
34 x 126 | d = 34 ±1.0 | P = 126 ±1.3 | b1 = 38 | b2 = 110 | 22.7
38 x 126 | d = 38 ±1.1 | P = 126 ±1.4 | b1 = 42 | b2 = 121 | 30.1
38 x 137 | d = 38 ±1.1 | P = 137 ±1.4 | b1 = 42 | b2 = 137 | 29.0
42 x 137 | d = 42 ±1.1 | P = 137 ±1.4 | b1 = 48 | b2 = 137 | 36.9
42 x 146 | d = 42 ±1.1 | P = 146 ±1.5 | b1 = 48 | b2 = 137 | 36.0

Table: Parameter by Chain Size, Treatment, Chain Grade, Test Force (kN) and Breaking Force min. (kN)
Header: Chain Size | Treatment | Chain Grade | Test Force (kN) | Breaking Force min. (kN)
14 x 50 | LTT | G90 | 175 | 277
14 x 50 | QO | G60 | 125 | 185
14 x 50 | C-N | G40 | 75 | 123
18 x 64 | LTT | G90 | 288 | 458
18 x 64 | QO | G60 | 190 | 305
18 x 64 | C-N | G40 | 125 | 205
19 x 64.5 | LTT | G90 | 319 | 510
19 x 64.5 | QO | G60 | 213 | 340
19 x 64.5 | C-N | G40 | 143 | 227
22 x 86 | LTT | G90 | 425 | 684
22 x 86 | QO | G60 | 285 | 456
22 x 86 | C-N | G40 | 190 | 304
24 x 86 / 24 x 87.5 | LTT | G90 | 500 | 814
24 x 86 / 24 x 87.5 | QO | G60 | 340 | 540
24 x 86 / 24 x 87.5 | C-N | G40 | 225 | 362
26 x 92 | LTT | G90 | 595 | 955
26 x 92 | QO | G60 | 400 | 637
26 x 92 | C-N | G40 | 265 | 425
30 x 108 | LTT | G90 | 793 | 1270
30 x 108 | QO | G60 | 525 | 848
30 x 108 | C-N | G40 | 350 | 565
34 x 126 | LTT | G90 | 1020 | 1635
34 x 126 | QO | G60 | 680 | 1089
34 x 126 | C-N | G40 | 450 | 725
38 x 126 / 38 x 137 | LTT | G90 | 1275 | 2040
38 x 126 / 38 x 137 | QO | G60 | 850 | 1360
38 x 126 / 38 x 137 | C-N | G40 | 565 | 906
42 x 137 / 42 x 146 | LTT | G90 | 1550 | 2495
42 x 137 / 42 x 146 | QO | G60 | 1038 | 1662
42 x 137 / 42 x 146 | C-N | G40 | 693 | 1108

Notes
Surface hardness and mechanical properties vary by treatment: LTT emphasizes higher breaking load with moderate hardness and greater elongation; QO yields higher hardness with reduced elongation; C-N produces a hard surface shell and a more ductile core. Carbonitrided shell depth can reach approximately 15% of the chain diameter.

Characteristics / Technical specifications

• Product name: Wear Resistant Round Link Chain
• Brand: TOPONE CHAIN
• Available treatments: LTT (G90), QO (G60), C-N (G40)
• LTT hardness: ~40–42 HRC (≈390 HB); elongation ~14%
• QO hardness: ~45–47 HRC (≈450 HB); elongation ~10%
• C-N surface hardness: up to ~64 HRC (≈800 HV); core elongation ~1–3.5%; carbonitriding depth up to ~15% of chain diameter
• Multiple chain dimensions available (d x p) with specified tolerances and associated weights (see dimensions table above)
• Test force and minimum breaking force provided per chain size and treatment (see parameter table above)