Product Overview: The working channel is a continuous conduit running through the insertion tube of an endoscope. Its core function is to allow various surgical instruments (such as biopsy forceps, cytology brushes, snares, injection needles, etc.) to pass smoothly and reach the lesion site for operation. Therefore, it must meet the following requirements:

Extremely low coefficient of friction; High wear resistance; Excellent chemical resistance; Good flexibility and compressive strength; Biocompatibility

Product Structure: Inner liner; Middle reinforcement layer; Outer jacket

Specifications: Outer diameter, length, and wall thickness can all be customized

Inner Liner: Made of PTFE, PFA, or FEP, providing a smooth, low-friction, and chemically resistant working surface.

Reinforcement Layer: This is the "skeleton" of the channel, responsible for providing compressive and torsional strength, preventing the channel from collapsing during negative pressure suction or instrument passage.

Outer Jacket: Typically a fluoropolymer compatible with the inner liner, used to wrap and protect the reinforcement layer, and bond the entire channel structure into a cohesive unit.

Manufacturing Process:

Mandrel Preparation: A metal rod with a diameter precisely equal to the inner diameter of the channel.

Extrusion of Inner Liner: PTFE or PFA materials are uniformly extruded over the mandrel using an extruder to form a smooth inner wall.

Coil Winding: On a precision CNC winding machine, stainless steel wire is tightly wound around the inner liner tube at preset spacing and tension.

Extrusion of Outer Layer: The assembly is fed into the extruder again to co-extrude a fluoropolymer outer jacket over the coil. The molten polymer flows into the gaps of the coil, and upon cooling, firmly bonds all components into a single unit.

Mandrel Removal: After cooling and setting, the mandrel is pulled out from the tube.

Post-Processing: Cutting to the required length and precision finishing of the ends (such as polishing, installing metal rings) to ensure a smooth transition when connecting to the instrument port, with no burrs that could potentially damage instruments or gloves.

Rigorous Testing:

Leakage Test: Ensures the channel is airtight to prevent fluid leakage during irrigation.

Push Force Test: Measures the force required to push specific instruments through the channel to ensure it meets tactile requirements.

Wear Resistance Test: Simulates repeated instrument passage to evaluate channel longevity.

Chemical Resistance Test: Immersion in disinfectants to assess aging performance.

Bending Test: Simulates endoscope bending to ensure the channel does not collapse or experience a sudden increase in resistance.