Washers - Bushing, Shoulder

Part Number	Description / PDF	Quantity
12SWS0456 Richco, Inc. (Essentra Components)	SHOULDER WASHER .115 ID .250 OD	940
12SWS0188 Richco, Inc. (Essentra Components)	SHOULDER WASHER .090 ID .187 OD	975
11SFW0025 Richco, Inc. (Essentra Components)	FINISHING WASHER .260 ID .683 OD	1000
B-434-2 Aearo Technologies, LLC – a 3M company	BUSHING 1/2" THERMOPLASTIC	1254
12SWS2574 Richco, Inc. (Essentra Components)	SHOULDER WASHER .380 ID .750 OD	3000
12SWS1233 Richco, Inc. (Essentra Components)	SHOULDER WASHER .253 ID .625 OD	0
12SWS1001 Richco, Inc. (Essentra Components)	SHOULDER WASHER, NATURAL, NYLON	24668
12SWS0394 Richco, Inc. (Essentra Components)	SHOULDER WASHER .177 ID .276 OD	1000
B-533-V2775 Aearo Technologies, LLC – a 3M company	BUSHING 3/4" THERMOPLASTIC	0
12SWS0475 Richco, Inc. (Essentra Components)	SHOULDER WASHER, NATURAL, NYLON	2631
12SWS1052 Richco, Inc. (Essentra Components)	SHOULDER WASHER .190 ID .488 O	0
12SWS0430 Richco, Inc. (Essentra Components)	SHOULDER WASHER, NATURAL, NYLON	4890
12SWS1066 Richco, Inc. (Essentra Components)	SHOULDER WASHER .193 ID .625 O	0
12SWS3612 Richco, Inc. (Essentra Components)	SHOULDER WASHER .190 ID 1.000 OD	500
12SWS1092 Richco, Inc. (Essentra Components)	SHOULDER WASHER .195 ID .500 O	0
12SWS0821 Richco, Inc. (Essentra Components)	SHOULDER WASHER, NATURAL, NYLON	4490
12SWS0431 Richco, Inc. (Essentra Components)	SHOULDER WASHER .125 ID .240 OD	1000
B-435-V2590 Aearo Technologies, LLC – a 3M company	BUSHING 1/2" THERMOPLASTIC	2476
10SCM006010 Richco, Inc. (Essentra Components)	SHOULDER WASHER 6.1MM ID 12.2MM	950
12SWS1169 Richco, Inc. (Essentra Components)	SHOULDER WASHER, NATURAL, NYLON	2000

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