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U.S. Department of Energy
Office of Scientific and Technical Information

Tracer bullet, self-sealing

Patent ·
OSTI ID:5603093

This self-sealing projectile is used in perforating oil-field well casing. The projectile has a casing-piercing nose portion, a seal-forming rear portion, and an annular flowable seal member, initially located just rear of the nose of the projectile. Upon impact, the forward motion of the seal member is arrested while the projectile continues forward momentarily until the sealing rear portion of the projectile contacts the seal member at which time the forward movement of the projectile is arrested and a seal is formed around the perforation caused by the entry of the projectile into the casing. The projectile has a longitudinal bore which is sealed at its rear end. A series of radially-extending ports near the nose is open with the bore. These ports are initially sealed by the seal member. Upon impact, the seal member moves away from the nose portion thereby exposing the ports, permitting fluid in the bore to be injected. An inertial piston may be located in the rear of the bore and arresting of the projectile will cause the inertial piston to move forward injecting material in the longitudinal bore. (5 claims)

Assignee:
Dresser Industries Inc.
Patent Number(s):
US 3419089
OSTI ID:
5603093
Country of Publication:
United States
Language:
English