|국가/구분||United States(US) Patent 등록|
|미국특허분류(USC)||251/636 ; 166/324|
|발명자 / 주소|
|출원인 / 주소|
|인용정보||피인용 횟수 : 22 인용 특허 : 1|
Disclosed is a surface controlled subsurface safety valve wherein the greater of well pressure and balance pressure assists in closing the safety valve. Well pressure assist for valve closure is obtained without creating additional depth sensitive limitations as the balance pressure approaches zero. Balance pressure assist for valve closure is obtained without well pressure tending to maintain the valve open. This abstract is neither intended to define the scope of the invention, which, of course, is measured by the claims, nor is it intending to be limi...
A surface controlled subsurface safety valve comprising: a housing having a bore extending therethrough; closure means disposed in said bore and adapted for movement between position opening and closing said bore; operator means for moving said closure means and axially movable within said bore between a first and second position; means for resiliently urging said operator means to its first position wherein said closure means closes said bore; control pressure responsive means for moving said operator means to its second position, said control pressure ...