THK SRG20 Linear Guide Block
The THK SRG20 is an ultra-high rigidity, heavy-load linear guide that utilizes caged rollers as rolling elements, offering twice the rigidity of conventional ball-type LM guidesTHK. Designed to global standard dimensions (interchangeable with THK HSR series), it ensures 4-way equal load capacity, smooth motion, and long-term maintenance-free operation for precision machinery requiring high stiffness and heavy load handling.
1. Product Overview
The THK SRG20 is an ultra-high rigidity, heavy-load linear guide that utilizes caged rollers as rolling elements, offering twice the rigidity of conventional ball-type LM guides. Designed to global standard dimensions (interchangeable with THK HSR series), it ensures 4-way equal load capacity, smooth motion, and long-term maintenance-free operation for precision machinery requiring high stiffness and heavy load handling.
2. Core Specifications (Source: THK Official Technical Catalog)
Basic Performance Ratings
- Dynamic Load Rating (C):
- SRG20XA: 20.6 kN
- SRG20XLA (Long Block): 26.7 kN
- Static Load Rating (C₀):
- SRG20XA: 46.9 kN
- SRG20XLA (Long Block): 63.8 kN
- Permissible Moments:
- M₁ (Rolling): 1.07 kN·m (XA), 1.44 kN·m (XLA)
- M₂ (Yawing): 1.07 kN·m (XA), 1.44 kN·m (XLA)
- M₃ (Pitching): 0.68 kN·m (XA), 0.91 kN·m (XLA)
- Contact Angle: 45° (4-row, equal load in radial, reverse-radial, and lateral directions)
- Operating Temperature: -20°C to 80°C
- Standard Preload: C0 (Standard Clearance), C1 (Slight Preload), C2 (Medium Preload)
Dimensional Data (Block)
| Parameter | SRG20XA | SRG20XLA |
|---|---|---|
| Block Height (M) | 30 mm | 30 mm |
| Block Width (W) | 63 mm | 63 mm |
| Block Length (L) | 86.2 mm | 106.2 mm |
| Mounting Hole | M6 x 10 | M6 x 10 |
| Weight (Block) | 1.49 kg | 1.92 kg |
Rail Specifications
- Rail Width: 30 mm
- Rail Height: 20 mm
- Standard Rail Lengths: 160–3000 mm
- Weight (Rail): 4.6 kg/m
3. Key Features (THK Official)
- Ultra-High Rigidity: Rollers (length >1.5x diameter) provide exceptional rigidity, double that of ball-type guides.
- 4-Way Equal Load: Uniform load capacity in radial, reverse-radial, and both lateral directions.
- Smooth, Stable Motion: Roller cages prevent skewing, minimize friction fluctuation, and ensure quiet, consistent movement.
- Long-Term Maintenance-Free: Cages eliminate roller-to-roller friction and enhance grease retention.
- Global Standard Dimensions: Direct interchangeability with THK HSR series for easy design-in.
- Superior Dust/Contamination Protection: Compatible with end seals, side seals, LaCS scrapers, and FS fluorine seals.
4. Standard Variants
- SRG20XA: Standard flange type (mount from top/bottom).
- SRG20XLA: Long-type flange (higher load/rigidity).
- SRG20XV: Narrow-width block (space-saving, top-mount only).
5. Typical Applications
- High-precision machine tools & machining centers
- Heavy-duty industrial robots & automation systems
- Precision measuring instruments
- Semiconductor manufacturing equipment
- Large-scale 3D printers & laser processing machines
- Press machinery & injection molding equipment
