SHOULDER BOLTS

Product Specification :
Product Specification: Shoulder Bolts (Stripper Bolts)
Shoulder Bolts, also commonly known as Stripper Bolts, are unique fasteners with three distinct sections: a head, an unthreaded enlarged shoulder, and a smaller diameter threaded end. They act as shafts, dowels, or pivots for moving parts, allowing for rotation or sliding while the threaded end is secured into a base component.
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1. Anatomy and Design
The precision of a shoulder bolt lies in the relationship between its three parts:
The Head: Usually a socket head (driven by an Allen key) to allow for high torque in recessed areas.
The Shoulder: A precision-ground smooth cylinder. The length and diameter of the shoulder are the most critical dimensions.
The Threaded Neck: A smaller diameter section that secures the bolt into the assembly.

2. Technical Specifications & Tolerances
Shoulder bolts are "precision" fasteners, meaning they are manufactured to much tighter tolerances than standard hex bolts.
Feature    Metric Specification    Imperial Specification
Diameter Tolerance    h8 (e.g., $+0.000 / -0.033\text{mm}$)    $+0.000 / -0.002\text{ inches}$
Material    Alloy Steel or 303/316 Stainless    Alloy Steel or 303/316 Stainless
Hardness (Alloy)    $32\text{--}43 \text{ HRC}$    $32\text{--}43 \text{ HRC}$
Tensile Strength    Up to $1100\text{ MPa}$    Up to $140,000\text{ PSI}$

3. Key Dimensions for Selection
When ordering shoulder bolts, you must specify four dimensions:
Shoulder Diameter: The diameter of the smooth shaft (determines the size of the hole in the moving part).
Shoulder Length: The length of the smooth shaft (determines the "travel" or thickness of the parts being held).
Thread Diameter: Often one size smaller than the shoulder (e.g., a $10\text{mm}$ shoulder bolt usually has an $M8$ thread).
Thread Length: The length of the threaded portion.

4. Common Applications
Pivot Points: Acting as an axle for pulleys, gears, or rollers.
Linkages: Connecting moving arms in mechanical assemblies.
Punch and Die Sets: In tool and die making, they are used as "stripper bolts" to guide the stripping plate as it moves against spring pressure.
Guides: Used as sliding rails for drawer mechanisms or heavy machinery slides.

5. Installation Performance
Seating: The shoulder should be tightened until the "undercut" (the shoulder face) sits flush against the base material. The moving part then sits on the shoulder with a slight clearance.
Pre-loading: Because the shoulder is meant to bottom out against a surface, you can apply high torque to the threads without "squeezing" or binding the moving part.
Reaming: To ensure a smooth fit, the hole in the moving part is often reamed rather than just drilled, ensuring it matches the "h8" tolerance of the shoulder bolt.