GB532111A - Improvements in well-head equipment - Google Patents

Abstract

532,111. Well-drilling equipment. SHAFFER, W. D., and SCHWEITZER, F. J. June 13, 1939, No. 17313. [Class 85] Well-drilling equipment comprises a spinnet or sleeve rotatable with the tool carrier which extends through the spinnet &c. on yielding packing means engaging said carrier to prevent blow-out through the bore of the spinnet &c. and a barrier associated with the packing means and adapted to yield outwardly on passage of an enlarged part of the carrier and to return to its original position under the influence of the packing means with which it is permanently associated. A collet 4 has radial lugs 5 adapted to be received between similar lugs on the casing head 3 the parts being locked by rotating threaded cap 8 to bring lugs 9 thereon over lugs 5 and permitting spring bolt 10 to engage one of a series of recesses 5a. A sleeve 17 and a driving band 15 are threaded together and locked by a screw 33 engaging castellations 34, and are rotatably supported by bearings 13, 25, on the collet. Packer 28 provides a seal around the sleeve 17, blow out within the latter being prevented by a packing nipple 19 which may have a substantially square section and is expansible to pass collars on the kelly K etc.; nipple 19 is reinforced by a partly embedded helical spring ring 22 forming a barrier to prevent the nipple from being blown out through the sleeve 17. A split collar 35 has lugs 36 engaging lugs 37 in the driving band 15 to communicate drive from the kelly K; the collar 35 is yieldingly held in the band 15 by a split spring ring 39. The spring ring 39 may be locked by a screw 41 to allow the parts to be removed from the casing head as a unit by the drill string.