Cutting/Deburring Wire/Hypotube

Hypotubes and stainless steel precision tubes are thin-walled, small-diameter tubes which we turn into specialized components often used in medical devices, aerospace, and other high-precision industries. Their manufacturing processes involve advanced techniques to ensure tight tolerances, durability, and specific material properties.

They are usually made from stainless steel (e.g., 304 or 316L), nitinol or titanium alloy, designed for applications like catheters, stents, or minimally invasive surgical tools.

Hypotubes

Their production involves several steps:

1. Material Selection

High-quality stainless steel is chosen for its corrosion resistance, biocompatibility, and strength. Common grades include 304, 316L, titanium or even nitinol for certain applications.

2. Tube Drawing

The process begins with a larger tube or rod.

Cold Drawing: The tube is pulled through a series of progressively smaller dies at room temperature. This reduces the diameter and wall thickness while increasing length.

Lubricants are used to minimize friction and heat.

Annealing: After drawing, the tube may be heat-treated (annealed) to relieve internal stresses and restore ductility, as cold drawing hardens the material.

3. Precision Sizing

Multiple drawing passes refine the tube to exact outer diameter (OD) and inner diameter (ID) specifications, often achieving tolerances as tight as ±0.0005 inches.

Wall thickness is carefully controlled, typically ranging from 0.001 inches to 0.010 inches for hypotubes.

4. Cutting and Shaping

The drawn tube is cut to length using precision methods like laser cutting or abrasive sawing.

Additional features (e.g., slots, holes, or tapered ends) may be added via laser cutting or micromachining, or by electrical discharge machining (EDM) for specific applications like catheter delivery systems.

5. Surface Finishing

Tubes are cleaned, polished, or electropolished to remove burrs and improve surface smoothness, critical for medical use where biocompatibility and cleanliness are paramount.

6. Quality Control

Hypotubes undergo rigorous inspection using tools like micrometers, optical comparators, plug gauges or X-ray imaging to verify dimensions, wall uniformity, and defect-free surfaces.

Stainless Steel Precision Tubes

Stainless steel precision tubes are similar to hypotubes but may serve broader purposes (e.g., instrumentation, automotive, or industrial applications). Their manufacturing process shares some steps with hypotubes but can vary in scale and complexity:

1. Raw Material

Stainless steel billets or coils (e.g., 304, 316, or 321 grades) are selected based on the desired properties like corrosion resistance or high-temperature strength.

2. Tube Formation

Seamless Tubes: A billet is pierced using a mandrel in a process called hot extrusion or rotary piercing to form a hollow tube.

The rough tube is then cold-drawn or pilgered (a specialized rolling process) to reduce size and improve precision.

Welded Tubes: A flat stainless steel strip is rolled into a tube shape, and the edges are welded together (e.g., TIG welding or laser welding).
The weld seam is smoothed and the tube is drawn to refine dimensions.

3. Cold Working

Like hypotubes, precision tubes are cold-drawn through dies to achieve tight tolerances and enhance mechanical properties (e.g., tensile strength).
Intermediate annealing steps may be applied to prevent cracking and maintain workability.

4. Heat Treatment

Annealing, solution annealing, or stress-relieving heat treatments adjust the microstructure, improving ductility or hardness depending on the application.

5. Finishing Processes

Tubes are cut to length, deburred, and polished. Finishes can range from bright annealed (a smooth, reflective surface) to matte or brushed, depending on use.
Passivation may be applied to enhance corrosion resistance by removing free iron from the surface.

6. Inspection and Testing

Precision tubes are checked for dimensional accuracy, surface quality, and mechanical properties (e.g., burst pressure or fatigue resistance). Non-destructive tests like ultrasonic or eddy current testing detect internal flaws.