Float collars and float shoe The float collars and float shoe are used to guide the casing to be put into the hole. It can adjust the floating power of the casing when the casing been laid in. That can certify the qualification of the cementing. The float collars and float shoe manufactured by our company use the spring driving back-pressure valve type. It has a high reliability. The structures are similar between float collar and float shoe. The lower end of the float collar is the pin connection which is connected with the casing. The upper end which is used for filling the cement has acinqfoil hole which can avoid the twist. The material of the float shoe body is the alloy steel . The upper end of the float shoe is connected with casing and its lower end is connected with the semilunar cement head. You can use the guide casing to lead it into the drilling hole. There is a back-pressure valve in the float shoe. You can use the oil well cement to fill the area between the float shoe and the body. The back-pressure can be cut by back-pressure valve. The upper hole and the lower hole will be open when the products after done . After the pressure of the circulating mud press the valve head into the lower place, the three collar valve on the valve tail will fall down automatically. The valve will press the valve seat tightly at the function of spring after the cement injection. And it will as a one-way valve function in the working. At that time, you could inject the mud into the pump from the upper end to the lower end, but the liquid of the well won`t be back in the casing below the valve or the outside circulation area of the casing.