DEVICE FOR CEMENTATION OF CASING STRING IN WELL Russian patent published in 1998 - IPC

FIELD: oil and gas production industry. SUBSTANCE: this is used for creation of oil and gas wells. Cementation device has barrel with central axial passage and radial passage. By means of connecting thread in ends of barrel, device is located as component of casing string. Mounted outside barrel is cylindrical housing with rings installed on its ends. Radial passage is closed by means of non-return valve. Located on housing and concentrically to it is bush which is made of material possessing higher deformation properties than material of housing. Groove is made in outer surface of housing and it is covered by bush. EFFECT: high efficiency. 6 cl, 3 dwg