U-Type Double-Sided Friction<a href='https://mengpengparts.com/hook-washer/' target="_blank"> Hook Washer</a> | Single Piece Assembly Anti-Wear Washer | Mengpeng HardwareU-Type Double-Sided Friction Hook Washer | Single-Piece Simplified Assembly Hinge Washer
Mengpeng U-type double-sided friction Hook Washer is an integrated one-piece standard hinge component specially developed to solve complicated two-gasket assembly problems. Equipped with dual independent friction surfaces and integrated anti-rotation hook, it replaces separate single dimple washer + flat washer, delivers double-sided abrasion protection for low-hardness plastic/aluminum moving brackets, simplifies production assembly and improves rotational damping uniformity for miniature thin pivot structures.
Core Design & Main Solved Industry Pain Points
Traditional single friction washer solution requires matching an extra flat washer, bringing extra parts, multiple assembly steps and low line efficiency. This U-shaped integrated part combines two friction planes into one component:
Dual friction surfaces isolate both soft moving housing and hard fixed metal plate from direct friction, avoid permanent groove abrasion;
Single-piece structure cuts assembly procedures, greatly boost production line output and reduce labor cost;
Integrated bent hook realizes circumferential anti-rotation & maximum angle limit, no washer follow-up rotation;
Oil storage dimples on both sides reserve lubricant to stabilize consistent torque for long cycles.
Structural Appearance Features
Whole U-shaped one-time stamping structure, two circular friction discs connected by integrated bent lug;
Double friction faces with oil storage blind pits to hold tiny lubricating grease, slow torque attenuation;
Dual 90° bending hook locks into bracket slot for full anti-rotation without shift;
Ultra-thin thickness range 0.4–0.8mm, fit compact slim pivot internal space.
Important Process Restriction: Surface polishing or grinding is forbidden, it will deform hook structure and cause assembly jamming failure.
Critical Dimension Control Standards
| Controlled Item | Tolerance Requirement | Failure Risk If Over Tolerance |
|---|
| Inner Hole Diameter | ≤0.05mm | Shaft eccentricity, unsmooth rotation & unstable torque |
| U-Bending Offset (Lug Center Distance) | ≤0.05mm | Two friction planes out of parallel, partial single-point friction |
| Connect Lug Width | ≤0.03mm | Too loose to lock slot; too tight difficult assembly |
| Bilateral Flatness After Bending | ≤0.02mm | Uneven contact, fluctuating rotation handfeel |
| Bending Surface Quality | No inner indentation, no outer crack | Lug fracture under repeated opening cycles, washer failure |
Full Technical Specification Sheet
| Parameter Item | Standard In-Stock Spec | Matching Engineering Value |
|---|
| Outer Diameter OD | 6.0mm ~ 24.0mm | Match miniature hinge bracket cavity |
| Inner Diameter ID | 3.55mm ~ 10.05mm (±0.05mm max tolerance) | Precise shaft fit to eliminate rotation shake |
| Available Thickness | 0.4 / 0.5 / 0.6 / 0.8mm | 0.5/0.6mm mainstream slim specification |
| Raw Material | 65Mn Spring Steel / SK7 Thin Sheet Steel | SK7 preferred for ultra-thin 0.4~0.6mm versions |
| Heat Treatment Hardness | HRC 43 ~ HRC 48 | Balance bending toughness & friction wear resistance |
Surface Treatment Selection By Working Environment
Nickel Plating: Indoor dry small electronics, cost-effective general anti-rust;
Electroless Nickel / Black Zinc: Indoor high humidity & high temperature devices, 24-hour salt spray resistance;
Zinc-Nickel Alloy Plating: Automotive & outdoor equipment, high salt spray & temperature alternating resistance.
Standard Production Process Flow
Raw Material Hardness Inspection → U-Type One-Piece Integrated Stamping → Deburr Edge Polishing → Fixture Compression Tempering → Anti-Corrosion Plating → Full Dimension & Flatness Test → Torque Rotation Simulation Test → Anti-Rust Sealed Packaging
Applicable Assembly Scenarios
Thin portable consumer electronics: tablet stands, fill light brackets, headset rotary shafts
Small household appliances: humidifiers, desktop fans, mini fryer flip lids
Lightweight automotive interior parts: sun visor, storage box simple hinges
Portable testing & miniature medical equipment adjustment joints
All slim compact pivot structures requiring simplified assembly workflow
Comparison: Single Dimple Washer VS Double-Sided U Hook Washer
| Comparison Item | Single Sparse Dimple Hook Washer | U-Type Double-Sided Friction Hook Washer |
|
|---|
| Assembly Parts Count | 2 pieces (washer + flat pad) | 1 single integrated piece |
|
| Friction Protection Surface | Only single side protects housing | Dual-sided protect both moving & fixed parts | Assembly Efficiency |
FAQ For Global Hardware Engineers & Buyers
What core advantage does double-sided U washer have over single hook washer?
It replaces two separate gaskets with one integrated part, simplifies assembly lines and cuts labor cost; dual friction planes protect both plastic/aluminum moving housing and metal fixed bracket, delivering smoother linear rotation torque without uneven friction.
Why polishing grinding is forbidden for this washer?
Grinding will change internal bending stress, deform the integrated hook structure, leading to slot jamming and assembly failure during mass production.
Which material to choose for ultra-thin 0.5mm pivot design?
SK7 thin spring steel is the optimal selection, with excellent bending performance without crack after U-shape forming.
Contact Mengpeng Hardware Standard Washer Bulk Supply
Dongguan Mengpeng Hardware Electronics Co., Ltd.
Official Website: https://www.mengpengparts.com
Email: sale1@mphardware.com
WhatsApp / Phone: +86 137 9888 8216
Structural Features
The component has a circular outer profile and circular inner hole, with a connecting “ear” structure between the two rings.
The ear section is formed with two 90-degree bends, creating a dual-hook mechanical engagement structure.
Important: This part must not be polished or ground. Surface grinding may cause the two hook structures to deform or interlock, affecting assembly performance.
Key Functional Role
In rotating shaft assemblies, this gasket acts as a friction transmission medium between non-hardened moving brackets and flat washers.
It helps generate a stable damping feel by creating dual friction interfaces, improving motion smoothness and rotational control.
Critical Control Dimensions
| Parameter | Key Requirement |
|---|
| Inner & Outer Diameter | Must ensure concentric alignment for stable rotation |
| Flatness | Critical for uniform friction contact and torque consistency |
| Bending Offset (Ear to Center Distance) | Key control dimension affecting assembly fit and damping force |
English
