Overview
The Murtfeldt G1 12 B-1 is an automatic chain tensioner in the Spann-Box® Size 1 series, designed for roller chains conforming to DIN 8187/8188 (ASA/JIS) standards. This tensioner is available in several variants to meet a wide range of requirements and features a robust design with steel housing that ensures high durability and reliable performance, even under demanding conditions. Mounted underneath the chain, the G1 12 B-1 uses a spring-loaded mechanism to automatically maintain proper tension throughout the drive’s operating range.
Key Features
- Automatic Spring Tensioning: The Spann-Box is mounted easily and efficiently underneath the chain, integrating seamlessly into existing systems.
- Size 1 Configuration: Engineered for 1/2″ pitch roller chains, optimizing compatibility with common industrial chain drive systems
- Durable Steel Housing: Robust design with steel housing ensures high durability and reliable performance, even under demanding conditions.
- Reversible Operation Support: Many tensioning systems are suitable for reversible operation.
- Reduced Vibration: The automatic chain tensioning system reduces vibrations and extends the lifespan of the chains.
Technical Specifications
- Manufacturer: Murtfeldt GmbH & Co. KG (Germany)
- Model Designation: G1 12 B-1 / Spann-Box® Size 1
- Mounting Position: Below chain (underneath)
- Chain Pitch Compatibility: 1/2″ (12.7 mm)
- Chain Standards: DIN 8187, DIN 8188 (ASA/JIS)
- Housing Material: Steel
- Operating Temperature Range: -40°C to 60°C (standard version)
- Spring Tension Options: Adjustable via locking pin mechanism
- Condition: Used, fully functional
Typical Applications
The Murtfeldt G1 12 B-1 is ideal for:
- Manufacturing machinery with continuous chain drives
- Conveyor systems requiring consistent chain tension
- Power transmission equipment in food, packaging, and automotive sectors
- Systems where guides combined with chain tensioners increase the lifespan of chains and are designed for low-friction movements in systems and machines, characterized by high wear resistance and excellent sliding properties.
- Applications demanding reduced vibration and extended chain service life
Compatibility & Replacements
Compatible With
- 1/2″ pitch (ISO 606) roller chains per DIN 8187 standard
- ASA/JIS roller chains per DIN 8188 standard
- Murtfeldt chain guides and sliding rail systems
- Standard chain drive systems with mounting provision below the chain
- Both single-direction and reversible chain drive applications
Replaces / Drop-In Replacement For
Verify exact interchangeability with your system integrator or contact Murtfeldt Application Technology before ordering. The G1 12 B-1 designation indicates Size 1 tensioner for 1/2″ chains; confirm profile type and housing configuration with your existing equipment.
Works With
- Murtfeldt Spann-Box® sliding guides and deflection profiles
- Standard ISO 606 roller chain systems
- DIN-compliant chain drive assemblies
- Manual and automatic chain tensioning layouts
- Reversible (bi-directional) chain drive configurations








