Stainless Steel Standoffs

What Are Stainless Steel Standoffs?

Stainless steel standoffs are precision-engineered fasteners designed to create space between two mounted components while providing robust structural support. These cylindrical spacers typically feature male-female threading (ranging from M2 to M12 metric threads or #4-40 to 1/2"-13 UNC/UNF imperial threads) and are manufactured from high-quality austenitic stainless steel grades, mainly 304 (1.4301) and 316 (1.4401), known for their superior corrosion resistance and mechanical strength.

Product Features & Technical Characteristics

Material Properties

• Grade 304 Stainless Steel: Contains 18-20% chromium and 8-10.5% nickel, offering excellent corrosion resistance in most environments.

• Grade 316 Stainless Steel: Includes 2-3% molybdenum for enhanced resistance to pitting and chloride corrosion, ideal for marine and chemical applications.

Mechanical Strength

• Tensile Strength: Ranges from 515-690 MPa for 304 grade and up to 827 MPa for 316 grade.

• Yield Strength: Approximately 205 MPa for 304 and 240 MPa for 316 stainless steel.

Temperature Resistance

• Continuous service temperatures range from -200°C to 800°C, with intermittent exposure possible up to 925°C without loss of structural integrity.

Surface Finish

• Standard finishes include #4 brushed finish (Ra 0.4-0.8 μm) or polished finish (Ra ≤ 0.2 μm).

• Optional passivation treatment per ASTM A967 enhances corrosion resistance by forming a protective oxide layer.

Dimensional Tolerances

• Manufactured to ±0.05 mm concentricity tolerance and ±0.1 mm length tolerance, ensuring precise alignment and fit.

Electrical Properties

• Volume resistivity of 0.73 μΩ·m at 20°C makes stainless steel standoffs suitable for grounding and electrical shielding applications.

Machining Process

Our stainless steel standoffs are fabricated using advanced CNC machining technology, ensuring:

• Precision turning and threading to meet ISO metric and UNC/UNF thread standards.

• Passivation to boost corrosion resistance and surface quality.

• Rigorous inspection with Go/No-Go thread gauges and coordinate measuring machines (CMM).

• Various surface finishes including polishing, black oxide coating, or customized treatments as requested.

Applications

Electronics & Telecommunications

• Provide 3-10 mm clearance for heat dissipation in PCB mounting.

• Serve as EMI/RFI shielding components through continuous metal contact.

• Used in server racks with M6 standoffs supporting up to 500N axial load for heavy equipment.

Architectural Glazing

• Employed in structural glazing with M10-M12 316L stainless steel standoffs, able to withstand coastal corrosion.

• Comply with European Standard EN 1993-1-4, transferring wind loads up to 3.5 kN/m².

Medical Equipment

• 316LVM standoffs compliant with ISO 13485 for surgical tools and implants.

• Surfaces electropolished to Ra ≤0.15 μm reduce bacterial adhesion, ideal for autoclave sterilization.

Transportation

• Railway applications use standoffs meeting DIN 5510-2 fire ratings.

• Marine applications require ASTM F593 compliance for exposure to saltwater.

Industrial Machinery

• Food processing equipment utilizes standoffs certified by 3-A Sanitary Standard 18-03, featuring radius corners and full penetration welds for hygienic design.

Other Industries

• Aerospace, optical equipment, and any environment demanding high corrosion resistance and mechanical strength.

Maintenance Procedures

Cleaning Protocols

• Routine cleaning with isopropyl alcohol (70-99%) and lint-free wipes.

• For marine environments, remove salt deposits using a 5% acetic acid solution.

• Re-passivate every 12-24 months with 20-50% nitric acid following ASTM A967 Method C.

Inspection Criteria

• Conduct quarterly inspections verifying:

• Thread engagement ≥ 1.5× nominal diameter.

• Absence of visible crevice corrosion (ASTM G78).

• Torque values within ±10% of installation specs.

Replacement Indicators

• Replace standoffs if:

• Pitting exceeds 0.1 mm depth (ASTM G46).

• Thread deformation is greater than 15% of pitch diameter.

• Evidence of galvanic corrosion between dissimilar metals.

Lubrication Requirements

• For threaded parts, apply:

• Molybdenum disulfide (MoS₂) grease for high temperatures above 400°C.

• PTFE-based lubricants for food-grade and sanitary environments.

• Maintain lubricant film thickness of 25-50 μm.

FAQ

Q1: What thread sizes are available for stainless steel standoffs?
A1: We offer metric threads (M2–M12) and imperial threads (#4-40 to 1/2"-13 UNC/UNF), with custom sizes available.

Q2: Are these standoffs suitable for marine environments?
A2: Yes, especially 316 stainless steel standoffs, which provide superior chloride and saltwater resistance.

Q3: Can these standoffs be used in medical applications?

A3: Absolutely. We provide 316LVM standoffs with electropolished finishes compliant with medical sterilization standards.

Q4: How often should maintenance be performed?
A4: Cleaning and inspection should be done quarterly, with passivation every 1-2 years depending on the environment.

Q5: What surface finishes are available?
A5: Standard finishes include brushed (#4), polished, passivated, and black oxide coatings. Custom finishes are also possible.