Spherical Plain Bearings

I. Part-Number Coding Rules (GB/T 304)

Basic structure: Type code + dimension-series code + bore code + supplementary code

1. Type Codes (Core)

GE: Radial spherical plain bearing (most widely-used)

GAC: Angular-contact spherical plain bearing

GX: Thrust spherical plain bearing

SI: Female-thread rod-end; SA: Male-thread rod-end

SB/SBB: Inch-size radial type; GEM/GEW: Wide inner ring / outer ring with snap-ring groove

2. Dimension-Series Codes (Width / Outer Diameter)

E: Standard series (often omitted in marking)

C: Extra-light series; H: Heavy series; EW/EM: Wide inner ring / wide series

3. Supplementary Codes (Structure / Seal / Lubrication)

ES: Split outer ring, with lubrication grooves / holes

2RS: Double-sided sealing rings

EC: Self-lubricating (PTFE liner, maintenance-free)

T/K: Self-lubricating rod-end; L: Left-hand thread

II. Common Part-Numbers and Specifications (d × D × B, mm)

1. Radial Spherical Plain Bearings (GE series, relubricatable type)

Part-Number	Bore d	Outer Diameter D	Width B	Features
GE10E	10	19	9	Standard, no lubrication holes
GE20ES	20	35	16	Split outer ring, with lubrication grooves
GE30ES-2RS	30	47	20	Double-sided seal, dust-proof and water-resistant
GE50ES-2RS	50	75	28	Heavy-duty, sealed version
GE100ES-2RS	100	150	70	Large-size, heavy-load

2. Self-lubricating Radial Type (GE…EC, maintenance-free)

GE15EC: 15 × 26 × 12

GE25EC: 25 × 40 × 16

GE40EC: 40 × 60 × 22

3. Rod-end Spherical Plain Bearings (SI / SA series)

SI20ET-2RS (female thread): d = 20 mm, M20×1.5, overall length 78 mm

SA30T/K (male thread): d = 30 mm, M30×2, overall length 117 mm

4. Angular-contact / Thrust Type

GAC25T (angular-contact): 25 × 47 × 15

GX20 (thrust): 20 × 42 × 15

III.Main Applications

For hinge joints and linkages requiring angular swing: Hydraulic cylinder hinge points of engineering machinery Linkage mechanisms, tie rods Excavators, cranes Automotive suspension and steering tie rods Agricultural machinery Metallurgical and hoisting equipment Testing machines, tooling fixtures

Model	d(mm)	D(mm)	B(mm)	C(mm)	α(°)	Cr(kN)	Cor(kN)	(r/min)	W(kg)
GE12ES	12	22	10	7	10	13.2	66	80	0.016
GE15ES	15	26	12	9	8	17.0	85	70	0.025
GE17ES	17	30	14	10	10	21.2	106	70	0.040
GE20ES	20	35	16	12	9	30.0	146	60	0.064
GE25ES	25	42	20	16	7	48.0	240	60	0.115
GE30ES	30	47	22	18	6	62.0	310	50	0.149
GE35ES	35	55	25	20	6	79.0	399	50	0.228
GE40ES	40	62	28	22	7	99.0	495	45	0.318
GE45ES	45	68	32	25	7	127	640	45	0.410
GE50ES	50	75	35	28	6	154	770	40	0.550