High purity, high temperature pipe thread sealant paste

Abstract

A pipe thread sealant paste composition comprising from about 30 to about 80 percent by weight of natural flake graphite particles of a size sufficient to pass through a 100 Tyler mesh sieve and a liquid carrier comprising a mixture of mineral oil and petrolatum. The paste composition preferably having a total ash content of no greater than about 1 percent by weight and containing leachable chlorides in amounts equal to or less than about 50 parts per million. The invention also relates to a method for preparing and applying the pipe thread sealant paste to pipe joints.

What is claimed is: 
     
       1. A .[.pipe thread sealant.]. paste composition comprising from about 30 to about 80 percent by weight of natural flake graphite particles of a size sufficient to pass through a 100 Tyler mesh sieve and a liquid carrier comprising a mixture of mineral oil and from 5 to 60 percent by weight petrolatum. 
     
     
       2. The .[.pipe thread sealant.]. paste composition according to claim 1 wherein the paste composition has a total ash content of no greater than about 3 percent by weight. 
     
     
       3. The .[.pipe thread sealant.]. paste composition according to claim 1 wherein the liquid carrier contains from 25 to 35 weight percent petrolatum and the balance being mineral oil. 
     
     
       4. The .[.pipe thread sealant.]. paste composition according to claim 1 wherein the natural flake graphite particles comprise a coarse fraction consisting of particles of a size which pass through a 100 Tyler mesh sieve and rest on a 200 Tyler mesh sieve and a fine fraction consisting of particles of a size which pass through a 200 Tyler mesh sieve. 
     
     
       5. The .[.pipe thread sealant.]. paste composition according to claim 4 wherein the natural flake graphite particles comprise about 50 percent by weight of said coarse fraction and about 50 percent by weight of said fine fraction. 
     
     
       6. The .[.pipe thread sealant.]. paste composition according to claim 2 wherein the total ash content is not greater than about 1 weight percent and the total chloride content is less than about 10 parts per million. 
     
     
       7. A .[.pipe thread sealant.]. paste composition consisting essentially of from about 30 to about 80 percent by weight of natural flake graphite particles, 5 to 60 percent by weight petrolatum with the balance mineral oil, said natural flake graphite particles including a coarse fraction and a fine fraction, said coarse fraction comprising particles of a size which pass through a 100 Tyler mesh sieve and rest on a 200 Tyler mesh sieve and said fine fraction comprising particles which pass through a 200 Tyler mesh sieve, the paste composition having a total ash content of no greater than about 1 percent by weight and containing leachable chlorides in amounts equal to or less than about 50 parts per million.