Abstract: The receiving station of LNG Dalian Company Limited often had interlock shutdown at commissioning because of the abnormal operation of SCV. Therefore, it is necessary to modify SCV to make the operation normal and satisfy the need of production. By cutting a section of protecting casing of ignition gun, lengthening the extending length downwards of the ignition gun, the original situation of needing 4-5 times of ignition to ignite SCV has been improved, raising the one-time success rate of ignition to 100%. By changing the positions of flame detector and observation mirror, the misoperation and shutdown of SCV because there is fire in furnace but it is not detected by flame detector no longer occur. By adding a throttling orifice plate at the air release valve of the main pipeline of natural gas, the interlock shutdown due to high inlet pressure does not happen anymore when igniting. The technical renovation above ensures the steady operation of SCV.