Description
YL3 YL Type Flanged Coupling – 14–45mm Bore Rigid Bolted-Flange Shaft Connector to GB5843-86
The YL3 YL type flanged coupling is a YL type flanged coupling designed to connect two co-axial cylindrical shaft ends rigidly through a bolted flange joint, conforming to Chinese national standard GB5843-86. With a 90 mm outer diameter, 14–45 mm bore range, and nominal torque rating of 25 N·m, the YL3 serves shaft connections in industrial drives where a rigid, zero-backlash connection is required combined with the ability to disconnect the two shaft ends by removing the flange bolts — without moving either shaft axially. Maximum speed rating is 6400 rpm for cast iron hubs and 10000 rpm for cast steel hubs. Overall hub length: 90 mm, face distance L0: 108 mm.
The YL type flanged coupling consists of two identical hub halves, each machined with a bore and keyway to receive one shaft end, and each terminating in a precision-machined circular flange. The two flanges are bolted together with 3×M8 reamed-hole precision bolts that both clamp the faces together and transmit shear torque through the bolt shank. Torque is transmitted from each shaft into its hub through the key-keyway engagement, through the hub body to the flange face, and across the bolted joint to the opposing hub and shaft. The result is a rigid, zero-backlash connection that can be separated by removing the 3 flange bolts without disturbing shaft alignment — an advantage over sleeve couplings that require axial shaft movement for installation or removal.
The YL3 conforms to GB5843-86, which specifies dimensions for flanged couplings for cylindrical shaft connections transmitting nominal torques from 10 to 20,000 N·m. Bore and keyway dimensions conform to GB3852-1997. The complete YL and YLD flanged coupling range is listed on our product catalog page.
Technical Specifications
| Parameter | Value |
|---|---|
| Model | YL3 |
| Type | YL Type Flanged Coupling |
| Standard | GB 5843-86 |
| Bore Range (d) | 14–45 mm |
| Outer Diameter (D) | 90 mm |
| Flange Diameter (D1) | 69 mm |
| Overall Length (L) | 90 mm |
| Spacer / Face Distance (L0) | 108 mm |
| Flange Bolts | 3×M8 |
| Nominal Torque (Tn) | 25 N·m |
| Max Speed – Cast Iron | 6400 rpm |
| Max Speed – Cast Steel | 10000 rpm |
| Rotational Inertia | 0.006 kg·m² |
| Mass | 1.99 kg |
Structure Drawing
Dimension Reference
Rigid Zero-Backlash Connection
The bolted flange joint transmits torque rigidly with zero angular play. Every rotational increment on the driving shaft is replicated exactly on the driven shaft — essential for position feedback and phase-critical drive applications.
Disconnect Without Shaft Movement
Removing the flange bolts disconnects the two shaft ends without moving either shaft axially. This allows motor removal, driven equipment service, or shaft inspection without disturbing bearing housings or shaft alignment.
Cast Iron / Cast Steel Options
Hub material choice of cast iron (6400 rpm) or cast steel (10000 rpm) covers both standard industrial speed requirements and higher-speed applications. The torque rating is the same for both materials.
GB5843-86 Standard Compliance
Full conformance to national standard GB5843-86 ensures dimensional interchangeability with other GB-compliant couplings. Keyway dimensions per GB3852-1997 ensure compatibility with standard motor and driven equipment shaft keyways.
Manufacturing
Typical Applications
- Process pump motor shaft connections — close-coupled pump rigid flanged drive coupling
- Marine auxiliary drive connections — offshore equipment rigid shaft coupling to marine material standards
- Mining equipment drive shaft connections — sustained duty rigid coupling for conveyor and agitator drives
- Compressor and blower motor connections — rigid flanged coupling for sustained high-torque drives
For custom bore configurations and volume supply, contact our technical team.
Customer Reviews and Case Studies
★★★★★
Netherlands — Industrial Fan OEM
The YL3 flanged coupling is our standard for connecting fan impeller shaft sections on our large industrial fan product range. The rigid connection maintains accurate shaft concentricity and the bolted flange allows impeller removal for cleaning without disturbing the drive bearing.
— Product Engineer, Rotterdam
★★★★★
South Korea — Chemical Processing Equipment
Installed on agitator drive shaft connections in our mixing vessel product range. The YL3’s 6,400 rpm iron / 10,000 rpm steel speed ratings cover our full agitator operating range and the coupling’s rigid connection prevents torsional play affecting the agitator speed control system.
— Equipment Engineer, Incheon
★★★★☆
Canada — Pump OEM
Used on motor to pump shaft connections in our close-coupled pump range. The YL3 flanged coupling allows motor removal for service without disturbing the pump shaft or impeller, which reduces our field service time significantly.
— Applications Engineer, Vancouver
Frequently Asked Questions
What alignment is required before installing a YL flanged coupling?
Both shaft ends must be accurately aligned before connecting the YL coupling. Recommended alignment tolerances are: parallel offset ≤ 0.03–0.05 mm; angular deviation ≤ 0.05 mm/m. These are tighter than flexible coupling requirements. Use a dial indicator or laser alignment tool. For YLD type, the alignment tenon provides centring on reconnection, but initial installation alignment is still required.
What torque should the YL coupling flange bolts be tightened to?
Tightening torque varies by bolt size: M6 approximately 10 N·m; M8 approximately 25 N·m; M10 approximately 50 N·m. Use a calibrated torque wrench and tighten bolts in a cross-pattern sequence. Reamed-hole (precision fit) bolts should be lightly oiled before insertion to prevent galling during tightening.
Can the YL/YLD coupling accommodate different bore sizes on each hub?
Yes. The two hub halves can be machined to different bore diameters, provided each bore falls within the model’s specified bore range. Specify d1 and d2 independently when placing your order.
What is the rated torque basis for YL/YLD flanged coupling?
The nominal torque Tn is the design torque for continuous operation. The coupling is sized based on the shear stress in the coupling bolts and the keyway bearing stress. For applications with shock or cyclic loading, apply a service factor (1.5 for smooth loads, 2.0–2.5 for shock loads) to the application torque before comparing with Tn.
Does the YLD spacer body add significant rotational inertia?
The spacer tube contributes additional rotational inertia compared to the standard YL type. For motor sizing and drive system dynamics calculations, the YLD’s additional inertia should be calculated using J = (m × r²)/2 for a thin-walled cylinder approximation and added to the total reflected inertia at the motor shaft.
Source the YL3 YL Flanged Coupling
Ever Power manufactures the YL3 and the complete YL/YLD flanged coupling range to GB5843-86 direct from our factory. Specify bore sizes, hub type (Y or J₁), and material (cast iron or cast steel) for a prompt technical and commercial response.