Selection Guide for Elevator Screw Bolts / Anchor Bolts (2026 Edition)
Choose the anchor bolt type based on the application scenario (this is the most crucial step).
Elevators are dynamic load and high-frequency vibration equipment, and the type of anchor bolt directly determines safety. Three types of scenarios are used for precise matching:
| Application Scenarios | Prohibited Uses | Recommended Anchor Bolt Types | Key Advantages | Applicable Areas |
|---|---|---|---|---|
| Main load-bearing fixings (traction machine, guide rails, hoistway structure) | Ordinary metal expansion bolts, plastic expansion anchors | Undercut mechanical anchor bolts | Mechanical interlocking, high tensile/shear strength, vibration resistant, suitable for dynamic loads | Post-anchoring for traction machine foundation, car guide rails, counterweight frame, and hoistway beams and columns |
| Auxiliary fixing (lightweight brackets, decorative elements, non-load-bearing pipelines) | Undercut anchor bolts (high cost) | Chemical anchors (standard type) or Grade 4.6 standard bolts | Easy installation, suitable for non-load-bearing connections, controllable cost | Elevator shaft lighting brackets, decorative panels, lightweight cable trays |
| Humid/corrosive environments (basements, coastal areas, chemical plant elevators) | Carbon steel ordinary anchor bolts | Stainless steel undercut anchor bolts (304/316) | Corrosion-resistant, rust-proof, suitable for harsh environments, lifespan ≥ 50 years | Basement elevator shafts, coastal project elevator shafts, corrosive media environments |
❌Absolute contraindication
Ordinary metal expansion bolts are strictly prohibited for use in the main load-bearing parts of elevators! Due to the continuous vibration of the elevator, they are prone to loosening and pulling out, posing a high risk of elevator safety accidents.
Determine the strength grade based on the load class.
The anchor bolt strength must match the elevator’s tonnage and operating speed, with tensile/yield strength being the key factor.
| Elevator operating conditions | Recommended anchor bolt strength grade | Key parameters (MPa) | Applicable scenarios |
|---|---|---|---|
| Standard passenger/freight elevators (≤2m/s, ≤1000kg) | 8.8 grade carbon steel anchor bolts | Tensile strength ≥800, Yield strength ≥640 | Used for fixing guide rails and traction machines in most residential and commercial elevators. |
| High-speed elevators (>2m/s), heavy-duty freight elevators (>1000kg), and elevators installed in existing buildings | Grade 10.9 carbon steel anchor bolts | Tensile strength ≥ 1000, Yield strength ≥ 900 | Main load-bearing nodes for high-speed elevators, heavy-duty freight elevators, and elevators installed in older residential areas |
| Non-load-bearing auxiliary components | 4.6 grade carbon steel anchor bolts | Tensile strength ≥ 400, Yield strength ≥ 240 | For decorative elements, pipelines, and other non-load-bearing parts |
| Humid/Corrosive Environments | 304/316 Stainless Steel Anchor Bolts | 304: Tensile strength ≥ 520; 316: Tensile strength ≥ 570 | Suitable for corrosive environments such as coastal areas and basements; strength meets non-heavy load requirements. |
✅ System requirements
Anchor bolts, nuts, and washers must be of the same grade (e.g., 8.8 grade anchor bolts with 8.8 grade nuts), and mixing with lower-grade components is strictly prohibited; anti-loosening measures (double nuts, thread locker, or spring washers) must be added to withstand vibration.
Choose materials based on the environment.
1. Normal dry environment (indoor elevator shafts, dry machine rooms)
Recommended: 8.8/10.9 grade hot-dip galvanized carbon steel anchor bolts
Advantages: Low cost, high strength, hot-dip galvanized coating provides corrosion protection, meeting conventional usage requirements.
2. Humid environment (basement elevator shafts, humid areas of elevator machine rooms)
Recommended: 304 stainless steel undercut anchor bolts
Advantages: Moisture-resistant, rust-proof, better cost-effectiveness than 316, suitable for 80% of humid environments.
3. Highly corrosive environment (seaside, chemical parks, acid/alkaline elevator shafts)
Recommended: 316 stainless steel undercut anchor bolts
Advantages: Resistant to chloride ion corrosion, extremely strong rust resistance, longest lifespan.
Specify specifications and parameters (size matching)
Diameter Selection
Main load-bearing parts: ≥M12 (M16 preferred). Using M8 or smaller diameter anchor bolts to fix the guide rails/traction machine is strictly prohibited.
Auxiliary parts: M6~M10 is sufficient for light loads.
Anchoring Depth
The depth of the anchor bolt embedded in the concrete should be ≥60mm (for M12 anchor bolts). For every increase in diameter size, the anchoring depth should increase by 10-15mm. Insufficient anchoring depth is strictly prohibited, as it can easily lead to pull-out failure.
Concrete Requirements
The concrete strength of the foundation should be ≥C30. If it is old concrete (C25 or below), the number of anchor bolts needs to be increased or higher specification anchor bolts should be used.