Patents Assigned to Technical Drilling Tools, Inc.
  • Patent number: 4171025
    Abstract: A hydraulic shock absorbing method for protecting the drill bit and drill pipe in rotary earth drilling comprising the steps of slidably moving an anvil connected to a drilling bit in a casing in response to increased down weight on the drill bit and sequentially transmitting further increases in the down weight and shocks from the anvil to a plurality of independently operating hydraulic pistons slidably mounted within the casing when down weight on the drill bit exceeds increasing predetermined amounts to activate the pistons in sequence. The drilling fluid within the casing is transmitted to first pressure areas on the anvil and the plurality of pistons and the drilling fluid is passed through the drilling bit to provide a pressure drop and then communicated to second pressure areas on the plurality of pistons.
    Type: Grant
    Filed: December 14, 1977
    Date of Patent: October 16, 1979
    Assignee: Technical Drilling Tools, Inc.
    Inventor: Grey Bassinger