Over mandrel extrusion for composite PCP stator

Patent metadata

Field	Value
Publication number	US-12285897-B2
Application number	US-202118002508-A
Country	US
Kind code	B2
Filing date	Jun 30, 2021
Priority date	Jun 30, 2020
Publication date	Apr 29, 2025
Grant date	Apr 29, 2025

Abstract

Techniques for forming a helical rubber hose are provided. Such techniques include modified crosshead extrusion techniques in which an elastomer is melted, fed into a crosshead assembly, and extruded on a helical mandrel fed through the crosshead assembly to form a hose. In techniques described herein, relative axial and rotational motion of the mandrel and a die plate at or on the outlet or output of the crosshead assembly are kinematically matched such that the distance of relative axial movement of the mandrel per one revolution equals one pitch of the mandrel.

First claim

What is claimed is:

1. A method of forming a hose, the method comprising:
melting an elastomer;
providing the melted elastomer to a crosshead assembly, wherein a die plate having an outlet port is mounted on an outlet of the crosshead assembly;
moving a helical mandrel relative to the crosshead assembly and the die plate outlet port while extruding the melted elastomer about the mandrel; and
kinematically correlating relative axial and rotational movement between the mandrel and the die plate,
wherein the mandrel is rotationally fixed and the die plate is configured to rotate about a longitudinal axis along which the mandrel extends through the die plate, and
wherein kinematically correlating the relative axial and rotational movement between the mandrel and the die plate comprises axially moving the mandrel a distance equal to one pitch of the mandrel as the die plate rotates one revolution.

2. A method of forming a hose, the method comprising:
melting an elastomer;
providing the melted elastomer to a crosshead assembly, wherein a die plate having an outlet port is mounted on an outlet of the crosshead assembly;
moving a helical mandrel relative to the crosshead assembly and the die plate outlet port while extruding the melted elastomer about the mandrel; and
kinematically correlating relative axial and rotational movement between the mandrel and the die plate,
wherein the die plate is rotationally fixed and the mandrel is configured to rotate about a longitudinal axis of the mandrel, and
wherein kinematically correlating the relative axial and rotational movement between the mandrel and the die plate comprises rotating the mandrel about the longitudinal axis 360° as the mandrel travels axially a distance equal to one pitch of the mandrel.

3. The method of claim 1 , wherein the elastomer is rubber.

4. The method of claim 1 , wherein extruding the melted elastomer about the mandrel comprises extruding the melted elastomer through a gap between an outer diameter of the mandrel and an inner diameter of the die plate outlet port.

5. A method for manufacturing a stator for a progressive cavity pump or positive displacement motor, the method comprising:
forming a hose, wherein forming the hose comprises:
melting an elastomer;
providing the melted elastomer to a crosshead assembly, wherein a die plate having an outlet port is mounted on an outlet of the crosshead assembly;
moving a helical mandrel relative to the crosshead assembly and the die plate outlet port while extruding the melted elastomer about the mandrel; and
kinematically correlating relative axial and rotational movement between the mandrel and the die plate, wherein kinematically correlating the relative axial and rotational movement between the mandrel and the die plate comprises causing the relative axial movement between the mandrel and the die plate a distance equal to one pitch of the mandrel while causing one revolution of the relative rotational movement between the mandrel and the die plate;

inserting the hose into a stator tube; and
filling a gap between an outer diameter of the hose and an inner diameter of the stator tube with a material.

6. The method of claim 5 , wherein the material is a thermoset resin or plastic.

7. The method of claim 6 , further comprising curing or vulcanizing the thermoset resin or plastic to solidify and bond the material to the hose.

8. The method of claim 5 , wherein the elastomer is rubber.

9. The method of claim 5 , wherein forming the hose further comprises removing the mandrel from the hose.

10. The method of claim 2 , wherein the elastomer is rubber.

11. The method of claim 2 , wherein extruding the melted elastomer about the mandrel comprises extruding the melted elastomer through a gap between an outer diameter of the mandrel and an inner diameter of the die plate outlet port.

Assignees

• Schlumberger Technology Corp

Inventors

• Pushkarev Maxim
• Hondred Pete
• Holzmueller Jason
• Goertzen William

Classifications

• B29L2023/005

  Hoses, i.e. flexible · CPC title

• B29K2101/10

  Thermosetting resins · CPC title

• B29K2021/00

  Use of unspecified rubbers as moulding material · CPC title

• B29D23/18 Primary

  Pleated {or corrugated} hoses · CPC title

• B29D23/001

  Pipes; Pipe joints (pleated hoses B29D23/18) · CPC title