GL chain coupling uses the chain to engage simultaneously with two parallel sprockets with the same number of teeth to connect the two halves of the couplings, which are normally enclosed in the housing to improve lubrication conditions and prevent contamination. A common chain is engaged with two parallel sprockets with the same number of teeth at the same time to achieve the connection of the two halves of the coupling. In order to improve lubrication conditions and prevent contamination, the coupling is generally sealed in the housing. The chain coupling has the advantages of simple structure, compact size, light weight and convenient assembly and disassembly. GL chain coupling has a simple structure (four pieces). Disassembly does not need to move the connected two shafts, compact size, light weight, has a certain compensation ability. It has the advantages of low installation accuracy, reliable operation, long service life and low cost. Roller chain couplings shall operate in well lubricated and protected conditions. Applicable to GL chain coupling shaft hole diameter D =16-190mm, shaft hole length L=42-352mm, nominal torque T=40-25000m, permissible speed 200-1400r/min without a shell, 900-4500r/min with a shell.