Tab-type coupling and method

A stab-like coupling for connecting an end portion of a smooth walled pipe to a fitting or another pipe, said coupling comprising in combination:

• a non-metallic coupling body having a first end and an internal recess adapted to receive the end portion of a smooth walled pipe;
• a generally elongated and hollow metallic insert disposed within said recess and about which the end portion of a smooth walled pipe is adapted to be received;
• at least one elastomeric seal ring disposed within said recess adapted to sealingly engage the end portion of a smooth walled pipe and said coupling body when said pipe is disposed within said seal ring;
• a non-metallic retaining collet disposed within said recess, said collet having a tapered external surface which converges in the direction of said coupling body first end and a toothed internal surface adapted to engage the end portion of a smooth walled pipe;
• a generally frusto-conical metallic backup ring retained by said coupling body, said backup ring having an internal surface generally complementary to said collet external surface and against which said collet is adapted to bear in the event of an attempted withdrawal of the smooth walled pipe from said coupling body;
• and,
• a non-metallic chamfer ring closely receivable through a central passage therein onto said elongated hollow insert adjacent said coupling body first end in retaining relationship to said insert for preventing accidental displacement of said chamfer ring from said insert during handling of said coupling while providing axial movement thereof along said insert responsive to an axial force applied thereto, said chamfer ring including a forward end area adapted to face said coupling body first end and a rear end area adapted to be engaged by an end portion end face of a smooth walled pipe, said forward end area having a portion thereof tapering toward said rear end area adjacent the outer diameter thereof with said rear end area having an outer diameter at least generally as large as the outside diameter of the end portion of a smooth walled pipe which is to be inserted into said coupling, whereby as the end portion of a smooth walled pipe is urged axially along said elongated insert and into said coupling body recess from said body first end, said chamfer ring will be urged along said insert in advance of the pipe end portion in order that the tapering portion of said chamfer ring forward end area will act as a pipe end portion lead to facilitate ease of insertion thereof into said coupling.

A method for providing ease of insertion of a pipe end portion into a stab-type coupling wherein said coupling includes a coupling body having a recess extending thereinto from a coupling body first end, an elongated hollow insert generally coaxially disposed in and extending longitudinally of said recess and at least pipe gripping means and sealing means encircling said insert in said recess adapted to retainingly engage and seal a pipe end portion inserted therethrough, said method comprising the steps of:

• (a) providing a chamfer ring receivable on said elongated hollow insert through a chamfer ring central passage, said chamfer ring being configured to have a forward end area and a rear end area with the outer diameter of the rear end area being at least generally as large as the outside diameter of a pipe end portion to be inserted into said coupliing said with at least a portion of said forward end area tapering toward said rear end area adjacent the outer diameter thereof;
• (b) placing said chamfer ring on said elongated insert with said forward end area facing said coupling body first end;
• (c) installing a pipe end portion on said elongated insert and moving said end portion axially along said insert until the terminal end face of the pipe end portion engages said chamfer ring rear end area;
• and,
• (d) urging the pipe end portion axially into said coupling recess with said chamfer ring acting as a pipe end portion lead for accommodating ease of pipe insertion into said recess through at least said gripping means and said sealing means.

A stab-type coupling for couplingly receiving an end portion of a pipe comprising:

• a body having a first end and an internal recess extending inwardly from said first end adapted to receive a pipe end portion;
• an elongated hollow insert disposed within said recess and about which a pipe end portion is adapted to be received;
• a pipe gripping member disposed within said recess surrounding a portion of said insert in a radially spaced relationship, said gripping member including pipe gripping means disposed on the inner surface thereof adapted to retainingly engage a pipe end portion inserted axially there past into said coupling body recess;
• a chamfer ring receivable through a central passage therein onto the exterior of said elongated insert adjacent said coupling body first end, said chamfer ring including a forward end area facing said first end and a rear end area adapted to be engaged by the end face of a pipe, said forward end area having an outer diameter at least generally as large as the outside diameter of a pipe which is to be inserted into said coupling, whereby as the end portion of a pipe is urged axially along said elongated insert and into said coupling body recess from said body first end said chamfer ring will be urged along said insert ahead of the pipe end portion in order that the chamfer ring forward end area will act as a pipe end portion lead through the gripping member means to facilitate ease of pipe end portion insertion into said coupling;
• a spacer ring located in said coupling body recess, said spacer ring including a cylindrical body disposed in a radially spaced encircling relationship with an axial portion of said insert, said spacer ring having a first end disposed adjacent the innermost end of said insert and a second end spaced from said first end axially along said insert;
• and,
• said second end of said spacer ring including pipe engaging means generally associated therewith and the inside diameter of said cylindrical body being greater than the diameter of said chamfer ring rear end area outer diameter for defining a chamfer ring receiving chamber, whereby said chamber is adapted to receive said chamfer ring when a pipe end portion is installed on said elongated insert and urged into said coupling body recess toward said insert innermost end for preventing interference to an engaging relationship between said spacer ring engaging means and the pipe end portion.

A stab-like coupling for connecting an end portion of a smooth walled pipe to a fitting or another pipe, said coupling comprising in combination:

• a non-metallic coupling body having a first end and an internal recess adapted to receive the end portion of a smooth walled pipe;
• a generally elongated and hollow metallic insert disposed within said recess and about which the end portion of a smooth walled pipe is adapted to be received;
• at least one elastomeric seal ring disposed within said recess adapted to sealingly engage the end portion of a smooth walled pipe and said coupling body when said pipe is disposed within said seal ring;
• a non-metallic retaining collet disposed within said recess, said collect having a tapered external surface which converges in the direction of said coupling body first end and a toothed internal surface adapted to engage the end portion of a smooth walled pipe;
• a generally frusto-conical metallic backup ring retained by said coupling body, said backup ring having an internal surface generally complementary to said collet external surface and against which said collet is adapted to bear in the event of an attempted withdrawal of the smooth walled pipe from said coupling body;
• a non-metallic chamfer ring receivable through a central passage therein onto said elongated hollow insert adjacent said coupling body first end, said chamfer ring including a forward end area adapted to face said coupling body first end and a rear end area adapted to be engaged by an end portion end face of a smooth walled pipe, said forward end area having a portion thereof tapering toward said rear end area adjacent the outer diameter thereof with said rear end area having an outer diameter at least generally as large as the outside diameter of the end portion of a smooth walled pipe which is to be inserted into said coupling, whereby as the end portion of a smooth walled pipe is urged axially along said elongated insert and into said coupling body recess from said body first end, said chamfer ring will be urged along said insert in advance of the pipe end portion in order that the tapering portion of said chamfer ring forward end area will act as a pipe end portion lead to facilitate ease of insertion thereof into said coupling;
• and,
• a non-metallic spacer ring in said coupling body recess, said spacer ring including a cylindrical body disposed in a radially spaced encircling relationsip with an axial portion of said insert, said spacer ring having a first end disposed adjacent the innermost end of said insert and a spacer ring second end spaced adjacent said seal ring, said second end including pipe gripping means generally associated therewith and the inside diameter of said cylindrical body being greater than said chamfer ring rear end area outer diameter for defining a chamfer ring receiving chamber adapted to receive said chamfer ring and prevent gripping interference between said spacer ring gripping means and the end portion of a smooth walled pipe when the pipe end portion is substantially fully inserted into said coupling recess.