Safety and security measures to prevent the crane from tipping over (1) Roads at the crane site must be level and strong and should deal with backfill and soft soil layers. If the soil is soft, the roads should be paved separately. The crane shall not be parked on a slope or moved high or low on either side of the crane. (2). Overloading is strictly prohibited. (3). Tilting the chain tensioner is prohibited. Tilting the crane can lead to overload and wire rope entanglement, double-row protection factory may even lead to rope breakage and overturning accidents. Tilted slings will also make the heavy objects vibrate rapidly after leaving the ground, which may damage people or other objects. (4). Slings for bundled components should be calculated. All lifting tools,screen tensioners should be checked regularly to identify damaged persons. The bundling method should be correct and firm to prevent the sling from breaking or slipping during the lifting process. Ningbo double maintenance plant to make the crane reduce weight and overturn. (5). Do not hang heavy parts and equipment with insufficient weight. Hoist hook (6). Six wind conditions prohibit lifting work. (7). The commander shall use a uniform command signal, which shall be clear and accurate. The crane driver shall follow the instructions.