Washers - Bushing, Shoulder

Part Number	Description / PDF	Quantity
12SWS0634 Richco, Inc. (Essentra Components)	SHOULDER WASHER .112 ID .350 O	0
12SWS1176 Richco, Inc. (Essentra Components)	SHOULDER WASHER .166 ID .545 O	0
12SWS3513 Richco, Inc. (Essentra Components)	SHOULDER WASHER .335 ID .875 OD	1000
12SWS0258 Richco, Inc. (Essentra Components)	SHOULDER WASHER .123 ID .283 OD	1000
12SWS1204 Richco, Inc. (Essentra Components)	SHOULDER WASHER .324 ID .600 O	0
12SWS0911 Richco, Inc. (Essentra Components)	SHOULDER WASHER .163 ID .428 O	0
12SWS3019 Richco, Inc. (Essentra Components)	SHOULDER WASHER .408 ID .750 OD	1000
12SWS2586 Richco, Inc. (Essentra Components)	SHOULDER WASHER .281 ID .750 OD	3000
12SWS1219 Richco, Inc. (Essentra Components)	SHOULDER WASHER .172 ID .625 O	0
12SWS4001 Richco, Inc. (Essentra Components)	SHOULDER WASHER .515 ID 1.125 OD	4000
24SW0250 Richco, Inc. (Essentra Components)	SHOULDER WASHER, 1/4 SCREW, .260	10790
12SWS2500 Richco, Inc. (Essentra Components)	SHOULDER WASHER .156 ID .510 O	0
12SWS2565 Richco, Inc. (Essentra Components)	SHOULDER WASHER .310 ID .750 OD	2000
12SWS0906 Richco, Inc. (Essentra Components)	SHOULDER WASHER .170 ID .625 OD	1000
12SWS0306 Richco, Inc. (Essentra Components)	SHOULDER WASHER .116 ID .250 OD	3000
12SWS1095 Richco, Inc. (Essentra Components)	SHOULDER WASHER .349 ID .502 O	0
10SCM003006 Richco, Inc. (Essentra Components)	SHOULDER WASHER 3.1MM ID 6.2MM O	900
12SWS3021 Richco, Inc. (Essentra Components)	SHOULDER WASHER .390 ID .745 OD	2880
12SWS2504 Richco, Inc. (Essentra Components)	SHOULDER WASHER .328 ID .687 OD	1000
24SW0004 Richco, Inc. (Essentra Components)	SHOULDER WASHER, #4 SCREW, .122	6059

Washers - Bushing, Shoulder

1. Overview

Washers - Bushing, Shoulder are precision mechanical components combining the functions of a bushing and a washer. Featuring a stepped outer diameter design, they provide axial load distribution while maintaining precise radial alignment. These components are critical in modern machinery for reducing friction, preventing vibration-induced loosening, and protecting assembly surfaces. Their engineered geometry enables simultaneous load-bearing and spacing functionality in compact designs.

2. Major Types & Functional Classification

Type	Functional Characteristics	Application Examples
Standard Shoulder Bushing Washer	Uniform wall thickness, concentric shoulder design	General-purpose machinery, automotive linkages
Threaded Shoulder Bushing	Integrated internal threading for secure fastening	Aerospace fastening systems, vibration equipment
Split Shoulder Bushing	Segmented design for easy installation/removal	Heavy equipment maintenance, shaft repair
Flanged Shoulder Washer	Extended flange for enhanced load distribution	Structural steel connections, rail systems

3. Structural Composition

Typical construction features:

Tapered or stepped outer diameter (15 -30 transition angle)
Controlled inside diameter tolerance ( 0.025mm to 0.1mm)
Material composition: Carbon steel (SAE 1045), Stainless Steel (AISI 304/316), Bronze (SAE 841), or Polymer (Nylon 6/66)
Surface treatments: Zinc plating (8-24 m), Black Oxide, DLC coating, or PTFE impregnation
Hardness range: 200-400 HV depending on application requirements

4. Key Technical Parameters

Parameter	Significance
ID/OD Dimensional Tolerance	Ensures proper fit with shaft and housing (typically H7/g6)
Shoulder Height	Determines axial positioning accuracy ( 0.1mm standard)
Hardness Rating	Affects wear resistance and load capacity
Surface Roughness (Ra)	Impacts friction coefficient (Ra 0.8-3.2 m typical)
Corrosion Resistance	Determines service life in harsh environments

5. Application Fields

Primary industries:

Automotive: Suspension systems, transmission linkages
Aerospace: Flight control actuation systems, engine mounts
Industrial Machinery: CNC machine tool spindles, robotic joints
Railway: Bogie pivot joints, coupler systems
Renewable Energy: Wind turbine pitch bearings, solar tracker mechanisms

6. Leading Manufacturers & Products

Manufacturer	Key Product Series	Technical Features
MISUMI	WSB Series	Modular design, 12 standard sizes
Nord-Lock Group	Shox Washer	Combined wedge-locking and bushing function
Bossard Group	Proliant SW	High-strength steel (12.9 class)
IKEUCHI	Oiles SPB	Self-lubricating polymer composite

7. Selection Guidelines

Key selection criteria:

Load Requirements: Calculate radial/axial loads using ISO 76:2006 standards
Environmental Factors: Consider operating temperature (-50 C to +300 C range)
Material Compatibility: Prevent galvanic corrosion between mating components
Installation Clearance: Allow 0.5-1.5mm radial play for thermal expansion
Case Study: In wind turbine pitch bearings, stainless steel shoulder washers with solid lubricant pockets demonstrated 40% longer service life versus conventional designs

8. Industry Trends

Emerging development directions:

Material innovation: Graphene-reinforced polymers for weight reduction
Smart integration: Embedded strain sensors for condition monitoring
Manufacturing advancement: Additive manufacturing for complex geometries
Sustainability focus: Bio-based coatings replacing hexavalent chromium
Standardization efforts: ISO/TC 2/SC 12 developing global design standards