柳工956EHDG4国四挖掘机的优点包括：1. 强大耐用的发动机：采用优质的国内知名品牌发动机，功率强劲，扭矩大，能够适应各种工况和作业要求。2. 高效的工作性能：具有独特的液力变矩器和行走系统，能够提供强大的牵引力和切割力，快速稳定地进行各种作业。3. 全新的液压系统：采用先进的液压技术，具有高效节能、稳定可靠的特点，提供更高的工作效率和精确的操控性能。4. 宽敞舒适的驾驶室：驾驶室设计人性化，视野开阔，座椅舒适，噪音低，空调系统高效，使操作员能够在长时间作业中得到良好的工作体验。5. 安全可靠的结构设计：机身结构坚固稳定，具有良好的抗冲击和承载能力，操控系统灵活可靠，能够在各种工况下保证操作员的安全。6. 易于维护和维修：开放式的维护空间和易拆卸的部件设计，方便操作员进行日常维护和维修，缩短停机时间，提高作业效率。7. 多种配件和配置选择：可根据作业需求选择不同的工作装置、斗容和其他附件，以适应不同的施工环境和作业要求。综上所述，柳工956EHDG4国四挖掘机在发动机、工作性能、液压系统、驾驶室、安全性、维护性和配置选择等方面都具备优越的特点，能够满足各种挖掘作业的需求。

The advantages of LiuGong 956EHDG4 national four excavator include:1. Powerful and durable engine: adopting high-quality domestic famous brand engine, it has strong power and high torque, which can adapt to a variety of working conditions and operational requirements.2. Efficient working performance: with unique torque converter and travel system, it can provide strong traction and cutting force, and carry out a variety of operations quickly and stably.3. New hydraulic System: Adopting advanced hydraulic technology with high efficiency and energy-saving, stable and reliable features, it provides higher working efficiency and precise maneuvering performance. 4. Spacious and comfortable cab: With humanized cab design, wide field of vision, comfortable seats, low noise, and efficient air-conditioning system, it enables the operator to have a good working experience during long-time operation. 5. Safe and reliable structural design: With solid and stable structure of the body, it has good impact and shock resistance, and is able to work quickly and stably. 6. The body structure is strong and stable, with good impact resistance and loading capacity, and the control system is flexible and reliable, which can ensure the safety of the operator under various working conditions. 6. Easy maintenance and repair: The open maintenance space and easy-to-dismantle parts design are convenient for the operator to carry out daily maintenance and repair, shorten the downtime and improve the working efficiency. 7. Various accessories and configurations to choose from: You can choose different working devices, bucket capacity and other accessories to meet different construction requirements. 8. Other accessories can be selected according to the operation requirements, so as to adapt to different construction environments and operation requirements. To summarize, LiuGong 956EHDG4 national four excavator has superior features in engine, working performance, hydraulic system, cab, safety, maintenance and configuration options, etc., which can meet the needs of various excavation operations.