In addition to all the features of single-stage casing head ，the double-stage casing head presents the following features:

Through putting the testing plug into 9-5/8 "hanger before pressure test of the third section drilling, Can be fully detected quality of the second section drilling.

The procedures and workforce of installing BOP can be shorten through Optimizing design of the casing head and the wellhead equipment can be installed at one time.

The protection sleeve of the third section drilling don?t have to be removed due to the optimum design of structure.

The float collar is mainly composed of spoiler, floating ball, shell and the basket. The casing float shoe is mainly composed of spoiler, floating ball, shell , the basket and guide shoe. The cone of spoiler center hole with floating ball can seal fluid reverse. The basket can support floating ball, flush well cycle and adjust performance of the drilling fluid . When cementing job,the basket support the floating ball and float collar is in the conduction state, so fluid can pass through freely. Float collar is back-pressure after running casing and the end of cementing job. Floating ball with sealing face of spoiler can prevent fluid backflow.

DYX-A 7 * 4-1/2

Combining the advantages of forging overcoat resistance to wear and high chromium wear-resistant anticorrosion inner sleeves.The overcoat is a forged steel. The hardness of high chromium inner after heat treatment reached 62 HRC. The company offers all kinds of premium chromium liners with domestic SL3NB, 3 nb, F three series pump,and abroad PZ-7100, 10P130, 12P160. Our productions fully implement the API spec7 export standards.

The length of products are more than onethird higher than that of national standard.

Piston assy, its main material is 40Cr, and piston rubber is made from import high polymer material, We research and development all kinds of pistons which are resistant to heat, pressure, abrasion and oil

Spiral casing centralizer has the advantages of simple structure, safe and high intensity. It can be widely used in vertical, deviated and horizontal well in the construction work. Rigid spiral centralizer can improve the efficiency of well cementation through cement paste revolving when cement injection in the vertical well. Spring centralizer is unlikely to support heavy casing in the deviated and horizontal well, so rigid spiral centralizer is the only choice.

Spiral casing centralizer has the advantages of simple structure, safe and high intensity. It can be widely used in vertical, deviated and horizontal well in the construction work. Rigid spiral centralizer can improve the efficiency of well cementation through cement paste revolving when cement injection in the vertical well. Spring centralizer is unlikely to support heavy casing in the deviated and horizontal well, so rigid spiral centralizer is the only choice.

Connecting outer pipe thread directing  to the surface casing pipe thread in the drilling operation.

The casing weight in addition to the surface casing can be hanged by the hanger.

Improve the stability of the drilling well head assembly Form enclosed spaces inside the casing string

Provide export of pressure between the two layers of casing string, pumping fluid in well in case of any emergency and testing pressure.

Spring casing centralizer is pressed into shape by mouding instead of welding and rivet. It has the advantages of simple structure, safe and reliable, high strength,good elasticity and convenient use. It can be widely used in vertical and deviated well in the casing work. Starting force and restoring force conform to API standards.

Element is made of nitrle/fluorine rubber and its temperature can reach 120℃/200℃.

Valve assy, Its main material is high quality alloy steel that higher than oil industry standards , and its rubber is new patten material. We manufacture and produce series high performance products that shock resistant under high temperature and high pressure.