Vented Screws Benefits
•  Enables faster, more efficient pump-down of HV & UHV systems
•  Eliminates virtual leaks
•  Relieves pressure from blocked gases
•  Provides means to vent contaminants found in screw voids
•  Promotes higher system throughput and improved yield
•  Allows for constant pressure and temperature equalization

Machine Screws

	What is a vented washer? When a screw is tightened over a flat washer, or directly an application without a washer, volumes of gas can be trapped in the space and beneath the fastener head along the screw shaft. Vented washers feature two bored canals on opposite sides of the flat face which provide an escape route for trapped gases.
	What is a virtual leak? A virtual leak is comprised of gases that are trapped physically within a pocket with only a miniscule escape path from the trapped pocket of gas into the chamber proper.

Precision Vented Screws in Special Alloys | RAYCHIN Fastening Solution Expert

RAYCHIN manufactures precision vented screws (hollow vented screws) in 25+ exotic alloys: 17-4 PH, Inconel 718, Titanium, Hastelloy, MP35N, A286, Monel & more. Vacuum-compatible, outgassing-reducing designs for semiconductor, aerospace & medical applications. Custom OEM vented screws with axial or cross holes. Global supplier.

Vented Screws: Engineered for Vacuum and Outgassing-Sensitive Applications

RAYCHIN is a premier manufacturer of high-performance vented screws and a recognized special alloy fastening solution expert. Vented screws, also known as hollow vented screws, vacuum screws, or outgassing screws, feature precision-drilled axial or cross holes that allow trapped air or gases to escape during assembly and operation. This critical design feature prevents pressure buildup, eliminates outgassing contamination, and ensures proper sealing in vacuum systems, semiconductor equipment, aerospace applications, medical devices, and high-purity processing environments.

The venting channel—typically an axial hole through the center of the screw or cross-drilled holes near the head—provides a path for gases to escape from blind holes, threaded cavities, or sealed chambers. This prevents virtual leaks in vacuum systems, eliminates hydraulic locking in fluid systems, and reduces contamination in high-purity applications. These screws are essential in vacuum chambers, semiconductor processing equipment, satellite systems, particle accelerators, medical implants, and analytical instruments where trapped gases can compromise performance or safety.

We engineer these precision components from over 25 advanced alloys, ensuring reliable performance in ultra-high vacuum environments (10⁻¹³ torr), corrosive atmospheres, high-temperature applications, cryogenic conditions, and biocompatible medical applications. Our vented screws are manufactured to exacting customer specifications and applicable ASTM, ASME, DIN, and ISO standards, with complete material certification, full traceability, and engineering support for custom applications.

Vented Screw Classifications

1. Vented Screw Design Types

2. Vented Screw Head Styles

3. Special Application Vented Screws

• Vacuum Vented Screws: For ultra-high vacuum (UHV) systems

• Semiconductor Vented Screws: For wafer processing equipment

• Medical Vented Screws: For implants and surgical instruments

• Aerospace Vented Screws: For satellite and spacecraft systems

• Cryogenic Vented Screws: For extreme low-temperature applications

• High-Temperature Vented Screws: For furnace and thermal processing

• Biocompatible Vented Screws: For medical implants and devices

• Non-Magnetic Vented Screws: For MRI and sensitive instrumentation

• Custom Vented Screws: Manufactured to your OEM specifications with unique vent configurations, head styles, drive types, thread forms, and material grades

4. Vent Hole Specifications

Full Material Portfolio with International Standard Designations

As a special alloy fastening solution expert, RAYCHIN produces vented screws in the following comprehensive range of high-performance materials:

1. Precipitation-Hardening Stainless Steels

17-4 PH (UNS S17400): ASTM A564 Type 630, AMS 5643, DIN 1.4542 — Available in H900, H1025, H1150, H1150+ tempers. Exceptional combination of high strength (up to 180 ksi) and good corrosion resistance. Excellent for vacuum applications, semiconductor equipment, and aerospace components. Low outgassing characteristics when properly processed. *Keywords: 17-4 PH vented screws, 17-4 PH vacuum screws.*

PH 13-8 Mo (UNS S13800): ASTM A564 Type 625, AMS 5629 — Superior strength (up to 220 ksi), exceptional toughness, and outstanding stress corrosion cracking resistance. Available in H950, H1000, H1050 tempers. Excellent for ultra-high vacuum applications, aerospace systems, and medical devices. *Keywords: PH 13-8 Mo vented screws, PH 13-8 Mo hollow vented screws.*

2. Nickel-Based Superalloys

Inconel® Alloys:

• Inconel 600 (UNS N06600): ASTM B166, AMS 5665 — General purpose high-temperature alloy with excellent oxidation and corrosion resistance to 2000°F. Good resistance to chloride stress corrosion cracking. Ideal for high-temperature vacuum systems, furnace applications, and nuclear vacuum systems. Keywords: Inconel 600 vented screws.

• Inconel 625 (UNS N06625): ASTM B446, AMS 5666 — Exceptional resistance to pitting, crevice corrosion, and high-temperature oxidation. Outstanding fatigue strength and resistance to chloride ions. Recommended for semiconductor processing, chemical vacuum systems, and marine applications. Keywords: Inconel 625 vented screws.

• Inconel 718 (UNS N07718): AMS 5663, ASTM B637 — High-strength alloy with exceptional creep rupture strength up to 1300°F. Excellent cryogenic properties. Ideal for aerospace vacuum systems, satellite components, and high-temperature semiconductor equipment. Keywords: Inconel 718 vented screws, Inconel 718 vacuum screws.

Monel® Alloys:

• Monel 400 (UNS N04400): ASTM B164, AMS 4675 — Superior resistance to seawater, steam, and caustic environments. Excellent corrosion resistance in reducing conditions. Recommended for marine vacuum systems, offshore instrumentation, and chemical processing. Keywords: Monel 400 vented screws.

• Monel K500 (UNS N05500): ASTM B865, AMS 4676 — Age-hardenable version offering increased strength and hardness while maintaining excellent corrosion resistance. Ideal for high-strength vacuum applications, oil & gas instrumentation, and marine systems. Keywords: Monel K500 vented screws.

Hastelloy® Alloys:

• Hastelloy C276 (UNS N10276): ASTM B574, AMS 5754 — Excellent resistance to a wide range of corrosive chemicals including strong oxidizers and reducing agents. Outstanding resistance to pitting and stress corrosion cracking. Recommended for chemical vacuum systems, semiconductor etch equipment, and pharmaceutical processing. Keywords: Hastelloy C276 vented screws.

• Hastelloy C22 (UNS N06022): ASTM B574, AMS 5755 — Superior resistance to oxidizing media and localized corrosion. Excellent in mixed acid environments. Ideal for aggressive chemical vacuum systems, bleaching equipment, and nuclear waste processing. Keywords: Hastelloy C22 vented screws.

• Hastelloy B2 (UNS N10665): ASTM B335 — Exceptional resistance to reducing acids like hydrochloric and sulfuric at all concentrations and temperatures. Recommended for acid processing vacuum systems, chemical reactors, and evaporators. Keywords: Hastelloy B2 vented screws.

Incoloy® Alloys:

• Incoloy 825 (UNS N08825): ASTM B423, AMS 5870 — Excellent resistance to reducing and oxidizing acids, stress corrosion cracking, and intergranular attack. Ideal for chemical processing vacuum systems, pickling equipment, and pollution control. Keywords: Incoloy 825 vented screws.

• Incoloy 925 (UNS N09925): ASTM B805 — High-strength, age-hardenable alloy with excellent resistance to sour gas environments. Recommended for downhole instrumentation, wellhead equipment, and subsea vacuum systems. Keywords: Incoloy 925 vented screws.

High-Temperature Alloys:

• Waspaloy (UNS N07001): AMS 5708, AMS 5824 — Precipitation-hardenable alloy with exceptional high-temperature strength to 1600°F. Excellent oxidation and creep resistance. Ideal for gas turbine vacuum systems, jet engine components, and high-temperature instrumentation. Keywords: Waspaloy vented screws.

• Nimonic® Series:

  • Nimonic 80A (UNS N07080): BS HR 501, AMS 5842 — Creep and rupture strength up to 1500°F. Excellent oxidation resistance. Recommended for exhaust system vacuum applications, heat treatment fixtures, and turbocharger components. Keywords: Nimonic 80A vented screws.

  • Nimonic 90 (UNS N07090): BS HR 502, AMS 5796 — Enhanced high-temperature properties with superior oxidation resistance. Ideal for gas turbine blades, high-temperature springs, and aerospace engine hardware. Keywords: Nimonic 90 vented screws.

3. Duplex & Super Duplex Stainless Steels

Duplex 2205 (UNS S32205/S31803): ASTM A193 B8S, EN 1.4462 — Twice the yield strength of 316 stainless with excellent chloride stress corrosion resistance. Outstanding pitting resistance (PREN 34-36). Recommended for offshore platform vacuum systems, desalination plant hardware, and marine instrumentation. Keywords: Duplex 2205 vented screws.

Super Duplex Alloys:

• Alloy 926 (UNS N08926): ASTM B691, EN 1.4529 — PREN >40 for severe chloride and seawater environments. Excellent resistance to crevice corrosion and pitting. Ideal for subsea vacuum systems, coastal infrastructure, and chemical tanker hardware. Keywords: Alloy 926 vented screws.

• AL-6XN® (UNS N08367): ASTM B691, AMS 5875 — Superior pitting and crevice corrosion resistance in highly chlorinated atmospheres. Outstanding resistance to seawater. Recommended for flue gas desulfurization, seawater cooling systems, and pharmaceutical equipment. *Keywords: AL-6XN vented screws.*

4. Titanium Alloys

Grade 2 Titanium (UNS R50400): ASTM B348, AMS 4921 — Excellent corrosion resistance with good formability and weldability. Outstanding seawater resistance and biocompatibility. Low outgassing characteristics. Ideal for medical vacuum systems, marine instrumentation, architectural hardware, and food processing. Keywords: Titanium Grade 2 vented screws.

Grade 5 Titanium (Ti-6Al-4V) (UNS R56400): AMS 4928, ASTM F467 — High strength-to-weight ratio (120 ksi typical), excellent corrosion resistance, and biocompatibility. Available in annealed and aged conditions. Excellent for aerospace vacuum systems, medical implants, satellite components, and racing applications. *Keywords: Titanium Grade 5 vented screws, Ti-6Al-4V vacuum screws.*

Grade 7 Titanium (UNS R52400): ASTM B348 — Superior corrosion resistance with palladium addition. Excellent in reducing and oxidizing acid environments. Ideal for chemical processing vacuum systems, desalination plants, and pollution control equipment. Keywords: Titanium Grade 7 vented screws.

Grade 23 Titanium (Ti-6Al-4V ELI) (UNS R56401): ASTM F136, ASTM F1472 — Extra-low interstitial version of Grade 5 with enhanced toughness and ductility. Superior biocompatibility. Recommended for medical implants, surgical instruments, and dental devices. Keywords: Titanium Grade 23 vented screws.

5. Refractory & Exotic Metals

Tantalum (UNS R05200): ASTM B365, AMS 7845 — Ultimate corrosion resistance in aggressive acid environments. Completely inert to most chemicals. Excellent biocompatibility. Ideal for chemical reactor vacuum systems, pharmaceutical processing equipment, high-purity applications, and medical implants. Keywords: Tantalum vented screws.

Zirconium 702 (UNS R60702): ASTM B550, ASME SB550 — Excellent resistance to sulfuric, hydrochloric, and nitric acids. Outstanding in organic acids and alkaline media. Ideal for nuclear fuel processing, chemical reactors, and aggressive chemical service. Keywords: Zirconium vented screws.

Zirconium 705 (UNS R60705): ASTM B550 — Niobium-stabilized version with enhanced strength and formability. Good corrosion resistance. Recommended for chemical processing, nuclear applications, and high-temperature service. Keywords: Zirconium 705 vented screws.

Molybdenum (UNS R03600): ASTM B387 — High temperature strength and stiffness for extreme thermal applications to 3000°F. Excellent thermal conductivity and low thermal expansion. Ideal for high-temperature vacuum furnaces, semiconductor processing equipment, and glass manufacturing. Keywords: Molybdenum vented screws.

TZM Molybdenum (Titanium-Zirconium-Molybdenum): ASTM B386 — Enhanced high-temperature strength and recrystallization resistance. Superior to pure molybdenum. Recommended for high-temperature vacuum applications, semiconductor, and aerospace. Keywords: TZM vented screws.

Tungsten (UNS R07005): ASTM B777 — Highest density and melting point for specialized radiation shielding and high-temperature applications. Exceptional wear resistance and thermal stability. Ideal for medical imaging equipment, aerospace counterweights, high-temperature fixtures, and radiation shielding. Keywords: Tungsten vented screws.

6. Specialty Stainless Steels & Nickel Alloys

Nitronic® Alloys:

• Nitronic 50 (XM-19) (UNS S20910): ASTM A193 B8N — High strength (twice the yield strength of 316 stainless), non-magnetic, excellent corrosion resistance. Good cryogenic properties. Recommended for medical imaging equipment, marine instrumentation, high-strength electronic enclosures, and aerospace components. Keywords: Nitronic 50 vented screws.

• Nitronic 60 (UNS S21800): ASTM A193 B8N — Superior wear and galling resistance with good corrosion properties. Excellent for frequently accessed fasteners and moving parts. Self-lubricating characteristics. Ideal for valve components, pump hardware, adjustable mechanisms, and instrumentation. Keywords: Nitronic 60 vented screws.

High-Performance Stainless:

• 254 SMO (UNS S31254): EN 1.4547, ASTM A479 — Excellent seawater and chloride resistance with high PREN value (>42). Outstanding pitting and crevice corrosion resistance. Recommended for offshore electronics, desalination hardware, coastal architectural fasteners, and marine applications. Keywords: 254 SMO vented screws.

• 310 Stainless Steel (UNS S31000): ASTM A276, AISI 310 — Outstanding high-temperature oxidation resistance up to 2000°F. Excellent in cyclic temperature conditions. Good carburization resistance. Ideal for furnace hardware, heat treat fixtures, exhaust system components, and high-temperature sensors. Keywords: 310SS vented screws.

• 316/316L Stainless Steel (UNS S31600/S31603): ASTM A276, ASTM A193 — Excellent corrosion resistance in marine and chemical environments. Good mechanical properties. Available in low-carbon version for improved weldability. Recommended for general vacuum applications, medical devices, food processing, and pharmaceutical equipment. Keywords: 316L vented screws, 316SS vacuum screws.

• Alloy 20 (Carpenter 20) (UNS N08020): ASTM B473 — Superior resistance to sulfuric acid and chloride stress corrosion. Excellent in mixed acid environments. Recommended for chemical processing equipment, pharmaceutical reactors, acid handling systems, and pickling equipment. Keywords: Alloy 20 vented screws.

• Alloy 330 (UNS N08330): ASTM B536 — Excellent carburization and oxidation resistance at elevated temperatures. Good resistance to thermal fatigue. Ideal for industrial furnaces, heat treating equipment, petrochemical processing, and high-temperature fixtures. Keywords: Alloy 330 vented screws.

7. Ultra-High-Strength Cobalt Alloys

MP35N (UNS R30035): AMS 5844, ASTM F562 — Ultimate tensile strength exceeding 300 ksi with exceptional toughness and corrosion resistance. Non-magnetic. Excellent fatigue strength and biocompatibility. Recommended for aerospace actuators, medical implants, downhole instrumentation, high-security fasteners, and marine applications. Keywords: MP35N vented screws.

MP159 (AMS 5846): Advanced cobalt-nickel alloy offering high strength and creep resistance at elevated temperatures. Superior to MP35N in high-temperature applications. Excellent fatigue and oxidation resistance. Ideal for gas turbine hardware, aerospace engine components, high-performance racing fasteners, and critical high-temperature assemblies. Keywords: MP159 vented screws.

Elgiloy® (UNS R30003): AMS 5833 — Non-magnetic, high-strength cobalt alloy with excellent corrosion resistance and fatigue properties. Good spring characteristics. Recommended for medical devices, aerospace components, spring applications, and instrumentation. Keywords: Elgiloy vented screws.

8. High-Strength Aluminum & Iron-Based Alloys

Aluminum 2024 (UNS A92024): ASTM B211, AMS 4120 — High-strength aluminum alloy with good fatigue resistance. Available in T3, T4, T8 tempers. Recommended for aerospace components, defense hardware, and high-performance applications. Keywords: Aluminum 2024 vented screws.

Aluminum 6061 (UNS A96061): ASTM B211, AMS 4117 — Versatile, heat-treatable aluminum alloy with good corrosion resistance and weldability. Available in T6 temper. Ideal for general vacuum applications, electronics enclosures, and architectural components. Keywords: Aluminum 6061 vented screws.

Aluminum 7075 (UNS A97075): AMS QQ-A-225/9, ASTM B211 — Available in T6, T73, T76 tempers. High strength-to-weight ratio (up to 83 ksi) with good corrosion resistance. Excellent machinability. Recommended for aerospace interiors, portable electronics, defense hardware, high-performance automotive components, and racing applications. Keywords: Aluminum 7075 vented screws.

A286 (UNS S66286): AMS 5731, ASTM A453 Grade 660 — Iron-based superalloy with excellent high-temperature strength and oxidation resistance to 1300°F. Good cryogenic properties and corrosion resistance. Ideal for aerospace engine hardware, turbocharger components, high-temperature electronic enclosures, and racing applications. Keywords: A286 vented screws.

9. Pure Nickel

Nickel 200/201 (UNS N02200/N02201): ASTM B160, ASME SB160 — High purity and excellent corrosion resistance in caustic environments. Good thermal and electrical conductivity. Non-magnetic. Recommended for caustic processing equipment, electronic components, food processing hardware, and alkali service. Keywords: Nickel 200 vented screws.

Custom Vented Screw Manufacturing & Engineering Solutions

As a special alloy fastening solution expert, RAYCHIN provides complete custom vented screw manufacturing services tailored to your exact specifications:

Manufacturing Capabilities

Engineering & Design Services

Material Selection Expertise:
Our metallurgical engineers analyze your application environment — vacuum level (10⁻³ to 10⁻¹³ torr), temperature range (-423°F to 3000°F), corrosive media exposure (pH 0-14), outgassing requirements, magnetic permeability needs (<1.05 μ), and biocompatibility requirements — and recommend the optimal alloy from our 25+ material portfolio.

Vent Hole Optimization:
We specialize in designing and manufacturing precision vent holes for specific applications:

• Axial through-holes for maximum venting of blind holes

• Partial axial holes for structural integrity with venting

• Cross-drilled holes for radial gas escape

• Intersecting hole patterns for complex venting paths

• Micro vent holes (0.1mm - 0.5mm) for minimal cross-sectional area reduction

Vacuum Compatibility Engineering:
Our vented screws are designed and manufactured with consideration for:

• Outgassing rates - materials and finishes selected for minimal outgassing

• Virtual leak prevention - vent paths designed to eliminate trapped volumes

• Particle generation - controlled edge breaks and surface finishes

• Bake-out compatibility - materials suitable for elevated temperature vacuum processing

• UHV compatibility - special processing for 10⁻¹³ torr applications

Thread Form Engineering:
Standard unified (UNC/UNF/UNEF), metric (ISO coarse/fine), or custom thread forms with venting considerations:

• Thread form optimized for vent path integration

• Special root radii for enhanced fatigue life with vent holes

• Left-hand threads for specific applications

Prototype Development:
Rapid turnaround prototype quantities (as few as 5 pieces) for design validation, vacuum testing, and functional testing prior to full production. Typical prototype lead time: 7-14 business days.

Quality Assurance & Certification

• Material Certification: Complete Material Test Reports (MTRs) to EN 10204 3.1/3.2 with full traceability to melt source

• Dimensional Inspection: CMM, optical comparator, vision system, and laser micrometry verification to customer specifications

• Hole Geometry Verification: Bore scope inspection, air gauging, and optical measurement of vent hole dimensions

• Mechanical Testing: Tensile, yield, hardness, torque-to-failure, and drive tool compatibility testing

• Vacuum Testing: Helium leak testing (to 10⁻¹² mbar·L/s) available upon request

• Outgassing Analysis: RGA (Residual Gas Analysis) for UHV applications

• Metallurgical Analysis: Microstructure examination, case depth verification, grain size determination

• Non-Destructive Testing: Liquid penetrant (FPI), eddy current inspection as required

• Process Certification: AS9100, ISO 9001, ISO 13485, ITAR, NADCAP, and PED compliant

Industry Applications & Engineering Recommendations

Why Choose RAYCHIN as Your Fastening Solution Expert?

25+ Years of Material Science Leadership:

Our metallurgical engineering team possesses deep expertise across the full spectrum of superalloys, refractory metals, and specialty stainless steels. We maintain a comprehensive database of material properties, outgassing characteristics, corrosion resistance data, and application performance records. We don't just manufacture fasteners — we engineer solutions optimized for your specific vacuum or venting application.

Complete Vertical Integration:

From raw material sourcing and certification through manufacturing, heat treatment, surface finishing, and quality inspection, all processes are performed in-house under strict quality control. This vertical integration ensures:

• Consistent quality from lot to lot

• Complete traceability from melt source to finished product

• Rapid response to design changes

• Competitive pricing without supply chain markups

• Shorter lead times for prototype and production quantities

Engineering Partnership:

We view ourselves as an extension of your engineering team. Our fastener engineers provide:

• Technical consultation on material selection based on vacuum and environmental requirements

• Vent hole design optimization for maximum effectiveness with minimal strength reduction

• Drive system specification for torque and assembly requirements

• Outgassing analysis and recommendations

• Failure analysis and corrective action support

• Finite element analysis (FEA) for stress distribution with vent holes

• Custom testing protocols for unique vacuum requirements

Global Standards Compliance:

Our products meet or exceed ASTM, ASME, DIN, ISO, JIS, BS, GB, and MIL-SPEC specifications, ensuring acceptance in regulated industries and global supply chains. We maintain current knowledge of international standards and can provide certification for any required specification.

Supply Chain Reliability:

We maintain strategic raw material inventory across our 25+ alloy portfolio, flexible manufacturing capacity, and robust quality systems to ensure consistent on-time delivery for both prototype quantities (5-100 pieces) and high-volume production runs (100,000+ pieces).

Sustainability Commitment:

We are committed to responsible material sourcing, energy-efficient manufacturing, and waste reduction. Our quality systems include:

• Conflict minerals compliance (due diligence per OECD guidelines)

• REACH and RoHS compliance for European markets

• Environmental management (ISO 14001 principles)

• Recycling and waste reduction programs

• Sustainable packaging initiatives

Technical Specifications & Ordering Information

Standard Size Ranges

Thread Specifications

Available Finishes for Vented Screws

Request Engineering Consultation & Quote

Contact RAYCHIN's special alloy fastening solution experts today with your specifications or CAD drawings. We provide confidential technical consultation, rapid response prototyping, and competitive pricing for standard and custom vented screw solutions in advanced alloys.

Email: sales@ray-chin.com
Web:www.ray-chin.com
Response Time: < 24 hours
Engineering Support: Available in English, Mandarin, German, and Spanish
Prototype Turnaround: 7-14 business days
Production Lead Time: 4-8 weeks depending on quantity and alloy

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