1. The landing collar comprises housing, ball seat and latch. The latch holds ball seat through pins. After the hanger is set, pressure is applied to release the ball seat. 由外壳、锁紧座和球座等组成。锁紧座与球座通过销钉连接，憋压座挂后再加压，球座脱落，循环重新畅通。
2. The domestic hot water system combining solar hot water heater and gas hot water heater is introduced, and the calculation model for the hot water system is established. 介绍了太阳能热水器结合燃气热水器的生活热水系统，建立了热水系统的计算模型。
3. Reason of hot-cracking of resin sand lathe bed casting occurring have been analyzed. It is founded that Hot-crack was caused by the casting residual hot stress and sand badness hot effect. 分析床身铸件产生热裂纹的原因，发现热裂纹是铸件凝固过程中形成的残余热应力和型砂不良热效应相叠加的结果。
4. The domestic hot water system combining solar hot water heater and gas hot water heater is introduced, and the calculation model for the hot water system is established. 介绍了太阳能热水器结合燃气热水器的生活热水系统，建立了热水系统的计算模型。
5. Reason of hot-cracking of resin sand lathe bed casting occurring have been analyzed. It is founded that Hot-crack was caused by the casting residual hot stress and sand badness hot effect. 分析床身铸件产生热裂纹的原因，发现热裂纹是铸件凝固过程中形成的残余热应力和型砂不良热效应相叠加的结果。
网络释义
hot finished steel pipe hot rolled tube hot rolling steel tube 热轧钢管;
hot mill hot rolling machine hot rolling mill 热轧机;
hot finished steel pipe hot rolled tube hot rolling steel tube 热轧钢管;
hot mill hot rolling machine hot rolling mill 热轧机;
hot mill hot rolling machine hot rolling mill 热轧机;
