Professional manufacturer of diaphragm, plum/jaw, cross slider and beam couplings — zero backlash, high rigidity, bore diameters from Φ3 to Φ78 mm. Trusted for CNC, robotics, semiconductor and automation systems worldwide.

One-piece aluminum hub with TPU elastomer spider. Compact, low inertia, zero-backlash torque transmission. Replaceable spider.
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Aluminum hub riveted with 304 stainless steel diaphragm — one-piece design for higher torque and true zero backlash.
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Black-oxide 45# steel, single & double diaphragm stepped type (OD56–190 mm) for heavy-duty servo and spindle drives.
Learn more →Four pillars behind every coupling we ship.
High-strength aluminum alloy bodies and 304 stainless steel diaphragms for strength, toughness and corrosion resistance.
CNC-machined in one clamping — high dimensional accuracy, clean threads, smooth assembly, stable connection.
Diaphragm elastic deformation and press-fit spider design deliver true zero-backlash, high-rigidity transmission.
5 series, 30+ models covering Φ3–126 mm — one-stop sourcing for every motion application. MOQ: 1 piece.
Diaphragm · Plum/Jaw · Cross Slider · Beam · Encoder — 30+ models
| Model | Bore d1,d2 (mm) | ΦD | L | Rated Torque (N·m) | Ang. (°) | Par. (mm) | Max Speed (rpm) | Torsional Stiffness (N·m/rad) | Weight (g) |
|---|---|---|---|---|---|---|---|---|---|
| CS-19+20 | 3–8 | 19 | 20 | 1 | 1 | ≤0.09 | 50,000 | 1,400 | 11 |
| CS-26+26 | 3–12 | 26 | 26 | 1.5 | 1 | ≤0.14 | 10,000 | 3,700 | 28 |
| CS-32+28 | 5–15 | 32 | 28 | 2 | 1 | ≤0.18 | 10,000 | 5,700 | 46 |
| CS-34+32 | 5–16 | 34 | 32 | 3 | 1 | ≤0.18 | 10,000 | 8,100 | 55 |
| CS-39+34.5 | 8–19 | 39 | 34.5 | 6 | 0.1 | ≤0.23 | 10,000 | 18,000 | 81 |
| CS-44+34.5 | 8–24 | 44 | 34.5 | 9 | 0.1 | ≤0.27 | 10,000 | 20,000 | 99 |
| CS-50+41 | 8–24 | 50 | 41 | 18 | 0.1 | ≤0.30 | 10,000 | 32,000 | 135 |
| CS-56+45 | 10–32 | 56 | 45 | 25 | 0.1 | ≤0.36 | 10,000 | 50,000 | 217 |
| CS-64+53 | 12–38 | 64 | 53 | 60 | 0.1 | ≤0.4 | 9,000 | 70,000 | 348 |
| CS-82+68 | 17–42 | 82 | 68 | 80 | 0.1 | ≤0.5 | 8,000 | 140,000 | 689 |
| CS-94+68 | 19–45 | 94 | 68 | 165 | 0.1 | ≤0.7 | 8,000 | 120,000 | 960 |
| CS-104+70 | 20–48 | 104 | 70 | 235 | 0.1 | ≤0.8 | 8,000 | 120,000 | 1,200 |
| CS-126+78 | 20–55 | 126 | 78 | 350 | 0.1 | ≤0.9 | 7,500 | 135,000 | 1,560 |
Model naming: CS-d1+d2 — d1 = input bore (mm), d2 = output bore (mm). Keyway and non-standard bores available on request.
| Model | Bore d1,d2 (mm) | ΦD | L | Rated Torque (N·m) | Ang. (°) | Par. (mm) | Max Speed (rpm) | Torsional Stiffness (N·m/rad) | Weight (g) |
|---|---|---|---|---|---|---|---|---|---|
| CD-19+27 | 3–8 | 19 | 27 | 1 | 0.12 | ≤0.18 | 50,000 | 700 | 14.6 |
| CD-26+35 | 5–12 | 26 | 35 | 1.5 | 0.15 | ≤0.18 | 10,000 | 1,850 | 37 |
| CD-28+32.2 | 5–14 | 28 | 32.2 | 1.5 | 0.15 | ≤0.18 | 8,000 | 2,500 | 45 |
| CD-32+41 | 5–14 | 32 | 41 | 2 | 0.17 | ≤0.18 | 10,000 | 2,850 | 67 |
| CD-34+45 | 5–15 | 34 | 45 | 3 | 0.17 | ≤0.18 | 10,000 | 4,050 | 77 |
| CD-39+50 | 8–19 | 39 | 50 | 6 | 0.22 | ≤0.36 | 10,000 | 9,000 | 118 |
| CD-44+50 | 8–24 | 44 | 50 | 9 | 0.22 | ≤0.36 | 10,000 | 10,000 | 144 |
| CD-50+57 | 8–24 | 50 | 57 | 18 | 0.23 | ≤0.54 | 10,000 | 16,000 | 235 |
| CD-56+64 | 10–32 | 56 | 64 | 25 | 0.27 | ≤0.72 | 10,000 | 25,000 | 318 |
| CD-68+75 | 12–38 | 68 | 75 | 60 | 0.31 | ≤0.8 | 9,000 | 35,000 | 492 |
| CD-82+98 | 17–42 | 82 | 98 | 80 | 0.55 | ≤0.8 | 8,000 | 70,000 | 1,013 |
| CD-94+98 | 19–45 | 94 | 98 | 165 | 0.55 | ≤1.3 | 8,000 | 50,000 | 1,502 |
| CD-104+102 | 20–48 | 104 | 102 | 235 | 0.55 | ≤1.3 | 8,000 | 60,000 | 1,650 |
| CD-126+110 | 20–55 | 126 | 110 | 350 | 0.60 | ≤1.3 | 8,000 | 67,500 | 1,980 |
Model naming: CD-d1+d2. Select CD when the CS standard length is insufficient or higher torque margin is required.
| Model | Bore d1,d2 (mm) | ΦD | L | Rated Torque (N·m) | Ang. (°) | Par. (mm) | Max Speed (rpm) | Torsional Stiffness (N·m/rad) | Weight (g) |
|---|---|---|---|---|---|---|---|---|---|
| CFC-14+22 | 3–6.35 | 14 | 22 | 0.2 | 1 | ≤0.6 | 46,000 | 20 | 10 |
| CFC-20+25 | 3–10 | 20 | 25 | 0.2 | 1 | ≤0.6 | 15,000 | 46 | 15 |
| CFC-20+30 | 3–10 | 20 | 30 | 0.2 | 1 | ≤0.6 | 15,000 | 46 | 19 |
| CFC-25+30 | 4–12 | 25 | 30 | 0.6 | 1 | ≤0.6 | 16,000 | 65 | 33 |
| CFC-25+34 | 4–12 | 25 | 34 | 0.6 | 1 | ≤0.6 | 16,000 | 65 | 42 |
| CFC-30+35 | 4–12 | 30 | 35 | 1 | 1 | ≤0.6 | 15,000 | 72 | 50 |
| CFC-40+40 | 5–16 | 40 | 40 | 6.5 | 1 | ≤0.6 | 12,000 | 72 | 60 |
| CFC-40+50 | 5–19 | 40 | 50 | 32 | 0.02 | ≤0.8 | 10,000 | 450 | 127 |
| CFC-40+55 | 6–24 | 40 | 55 | 32 | 0.02 | ≤0.8 | 10,000 | 450 | 154 |
| CFC-55+49 | 10–32 | 55 | 49 | 46 | 0.02 | ≤0.8 | 8,000 | 1,200 | 241 |
| CFC-55+78 | 8–32 | 55 | 78 | 46 | 0.02 | ≤0.8 | 8,000 | 1,200 | 341 |
| CFC-80+114 | 14–40 | 80 | 114 | 109 | 0.02 | ≤1.0 | 6,000 | 2,800 | 433 |
| CFC-95+90 | 15–45 | 95 | 90 | 109 | 0.02 | ≤1.0 | 6,000 | 2,800 | 583 |
| CFC-105+140 | 22–65 | 105 | 140 | 420 | 0.02 | ≤1.0 | 3,800 | 3,400 | 1,650 |
| CFC-120+160 | 22–65 | 120 | 160 | 520 | 0.02 | ≤1.0 | 3,000 | 4,600 | 3,230 |
Model naming: CFC-d1+d2. TPU spider is replaceable.
| Model | Bore d1,d2 (mm) | ΦD | L | Rated Torque (N·m) | Ang. (°) | Par. (mm) | Max Speed (rpm) | Torsional Stiffness (N·m/rad) | Weight (g) |
|---|---|---|---|---|---|---|---|---|---|
| FZG-30+50 | 9.9–14 | 30 | 50 | 14.8 | 0.8 | ≤0.6 | 20,000 | 510 | 115 |
| FZG-35+55 | 9.9–16 | 35 | 55 | 16 | 0.8 | ≤0.6 | 18,000 | 510 | 185 |
| FZG-40+55 | 10–19 | 40 | 55 | 19 | 0.8 | ≤0.8 | 18,000 | 520 | 250 |
| FZG-40+66 | 10–22 | 40 | 66 | 19 | 0.8 | ≤0.8 | 18,000 | 550 | 280 |
| FZG-55+78 | 12–22 | 55 | 78 | 68 | 0.8 | ≤0.8 | 13,000 | 1,510 | 700 |
| FZG-65+90 | 14–28 | 65 | 90 | 190 | 0.8 | ≤0.8 | 10,500 | 2,800 | 1,100 |
| FZG-80+114 | 19–45 | 80 | 114 | 270 | 0.8 | ≤0.8 | 8,600 | 3,600 | 1,850 |
| FZG-95+126 | 20–50 | 95 | 126 | 440 | 0.8 | ≤1.0 | 7,200 | 4,700 | 5,680 |
| FZG-105+140 | 22–50 | 105 | 140 | 720 | 0.8 | ≤1.0 | 5,800 | 5,800 | 7,730 |
| FZG-120+160 | 24–65 | 120 | 160 | 1,040 | 0.8 | ≤1.0 | 7,200 | 7,200 | 9,300 |
Model naming: FZG-d1+d2. 304 stainless steel body — ideal for sanitary, corrosive and humid environments.
Black-oxide 45# carbon steel hubs with stepped diaphragm design for heavy-duty power transmission. High torsional strength and durability for large servo and spindle drive applications.
| Type | Model (OD × L) |
|---|---|
| Single Diaphragm | OD56 – L45 |
| OD68 – L56 | |
| OD82 – L68 | |
| OD94 – L68 | |
| OD104 – L80 | |
| OD115 – L91 | |
| OD126 – L93 | |
| OD144 – L103 | |
| OD152 – L104 | |
| OD178 – L124 | |
| OD190 – L145 | |
| Double Diaphragm | OD56 – L64 |
| OD68 – L74 | |
| OD82 – L98 | |
| OD94 – L98 | |
| OD104 – L102 | |
| OD115 – L110 | |
| OD126 – L115 | |
| OD144 – L166 | |
| OD152 – L184 | |
| OD178 – L218 | |
| OD190 – L260 |
Data source: CROCNC internal quotation sheet. Custom bore diameters and keyways available on request.
More series available: CRO-HC cross slider · CRO-IC beam · CRO-B encoder · CRO-SE/LF/CW high-sensitivity diaphragm · CRO-NB/MB 8-screw high-rigidity. Download full catalog (PDF) →
Every photo below is from our own production line in Shenzhen.





Shenzhen Crocnc Equipment Co., LTD (CROCNC) is a professional enterprise integrating the R&D, manufacturing and sales of precision shaft couplings. Located in Guangming District, Shenzhen, we focus on making couplings for servo and stepping motor applications — doing one thing and doing it well.
From CNC machining of aluminum and stainless steel components to surface treatment, assembly and packing, our in-house capability ensures consistent quality across the entire range. Our philosophy is "Customer First" — building a recognized coupling brand with proprietary intellectual property.


Serving 30+ industries across automation and precision machinery.
Servo motor to ball screw connections on milling, turning and grinding machines.
Joint and axis transmission for industrial and collaborative robot arms.
High-precision motion stages where zero backlash is critical.
Beam delivery and axis drive coupling for cutting heads.
Pick-and-place, bonding and assembly equipment.
Precision drive components for photovoltaic and battery manufacturing lines.
For inquiries, custom specifications, OEM/ODM or export orders.