Screws, Bolts

Part Number	Description / PDF	Quantity
3425200025 Richco, Inc. (Essentra Components)	HEX SOCKET CAP SCREW, 1/4-20 THR	4948
010640R075 Richco, Inc. (Essentra Components)	ROUND SLOTTED SCREW 6-40 THREAD	1000
010256CD031 Richco, Inc. (Essentra Components)	BINDER COMBINATION SCREW 2-56	0
010832R100 Richco, Inc. (Essentra Components)	ROUND SLOTTED SCREW, NATURAL, NY	6000
50M080125K040 Richco, Inc. (Essentra Components)	HEX SLOTTED SCREW, M8 X 1.25 THR	495
9303 Keystone Electronics Corp.	MACH SCREW PAN HEAD SLOTTED 4-40	10300
020832A100 Richco, Inc. (Essentra Components)	COUNTER SUNK SCREW, SLOTTED, 82	9875
9409 Keystone Electronics Corp.	MACH SCREW BINDING SLOTTED #6-32	8500
NSS-4-6-01 Richco, Inc. (Essentra Components)	MACH SCREW PAN HEAD SLOTTED 4-40	2360
010440P031 Richco, Inc. (Essentra Components)	PAN SLOTTED SCREW 4-40 THREAD 5/	635
020632A075 Richco, Inc. (Essentra Components)	82 SLOTTED CSK SCREW 6-32 THREAD	640
3404400100 Richco, Inc. (Essentra Components)	SOCKET HEAD BOLT, NATURAL, NYLON	9325
021032B062 Richco, Inc. (Essentra Components)	100 SLOTTED CSK SCREW 10-32 THRE	760
010440F043 Richco, Inc. (Essentra Components)	FILLISTER SLOTTED SCREW 4-40 THR	980
SSBOLT6250-C Panduit Corporation	STAINLESS STEEL,5/8-11 X 1/2" HE	0
31025050 Richco, Inc. (Essentra Components)	SHOULDER SCREW, HEX SOCKET, #10-	500
M12-20-M-N-UT US Micro Screw	M1.2X2MACH SCR,NKL,ULTTHN,PH	15000
M3449-SS RAF	11MM HD X 9MM TL X M5	296
3410320050 Richco, Inc. (Essentra Components)	SOCKET HEAD BOLT, NATURAL, NYLON	7728
50M030050P006 Richco, Inc. (Essentra Components)	PAN PHILLIPS SCREW, NATURAL, NYL	858

Screws, Bolts

1. Overview

Screws and bolts are threaded fasteners designed to mechanically join materials. Defined by their helical threads and head configurations, these components enable removable or permanent assemblies in engineering applications. Their importance in modern technology stems from their ability to provide high clamping forces, ease of installation, and adaptability across industries ranging from aerospace to consumer electronics.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Hex Bolt	High torque transmission, hexagonal head for wrenching	Structural steel connections in construction
Socket Head Cap Screw	Internal hex drive, cylindrical head for precise torque	Machinery assemblies requiring flush mounting
Self-Tapping Screw	Drills own thread in mating material during installation	Metal sheet joining in HVAC systems
Carriage Bolt	Dome head with square neck to prevent rotation	Wood-to-metal fastening in furniture
Anchor Bolt	Expandable end for concrete substrate anchoring	Foundation connections in industrial equipment

3. Structure and Composition

Typical configurations include: - Head (hexagonal, cylindrical, or countersunk) - Bearing surface (under-head contact area) - Shank (unthreaded cylindrical section) - Threaded portion (metric or imperial pitch) - Point (tapered or blunt end) Materials range from carbon steel (grades 4.8-12.9) to stainless steel (A2/A4), titanium, and specialty alloys. Surface treatments include zinc plating, galvanization, and phosphate coatings.

4. Key Technical Parameters

Parameter	Significance
Tensile Strength (MPa)	Determines maximum axial load capacity
Proof Load (MPa)	Maximum stress before plastic deformation
Hardness (HV/HRC)	Indicates wear resistance and brittleness
Thread Pitch (mm/TPI)	Dictates engagement quality and assembly speed
Corrosion Resistance Class	Measured by salt spray test hours (e.g., ISO 9227)

5. Application Fields

Automotive: Cylinder head bolts (torque-to-yield), wheel studs
Aerospace: NAS/AN standard fasteners in airframe assemblies
Construction: M20+ diameter bolts in steel bridges
Electronics: 0-80 UNF screws in circuit board mounting
Renewables: Wind turbine tower segment connections

6. Leading Manufacturers

Manufacturer	Key Products
Hilti Corporation	HIT-HY 150 MAX adhesive anchors
Bossard Group	Delta PT self-tapping screws for aluminum
Stanley Black & Decker	FASTORQ structural hex bolts
ARaymond	Push-on quick-connect fasteners for automotive

7. Selection Guidelines

Key considerations:

Material compatibility (e.g., stainless steel in marine environments)
Load requirements (static vs. dynamic loading conditions)
Environmental exposure (temperature range, chemical contact)
Installation method (manual vs. automated torque-controlled tools)
Cost optimization (balance between performance and budget)

Example: Selecting A4-70 stainless bolts for coastal infrastructure projects ensures seawater resistance while maintaining 700MPa tensile strength.

8. Industry Trends

Current developments include:

Hybrid composite fasteners for weight reduction in EVs
Smart bolts with embedded strain sensors (IoT integration)
Self-lubricating coatings reducing installation torque variability
Additive manufacturing of customized thread profiles
Sustainability initiatives: Recyclable alloy development and process energy reduction