Case Studies: Fine & Ultra-Fine Wire Manufacturing Technology

Case studies Case Studies

Sakai Wire Co., Ltd. is a Precision Wire-Drawing Manufacturer specializing in Fine to Ultra-Fine Stainless Steel Wire.

This page showcases examples of Custom Specifications—such as Non-Standard Wire Diameters, Mechanical Properties, Surface Quality, Winding Spool-types, Length control, Sliding performance, Lubricants and others—developed through Prototype and Small-lot Production.

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Diameter SpecificationIn-house Die Processing / Small-lot Mechanical PropertiesCondition Design / Non-standard Surface QualityNon-slip Drawing / Precision Springs Winding ChangeLarge-Bobbin / Spring Wire Length ControlRewinding / Small-lot Winding Surface ReformingMPSR / Lubricity Breakage PreventionLubricity / Knitted Mesh Difficult FormingLubricity / Customized

■ Case Studies

Each example summarizes the Key Points—Specifications, Requirements, and Results—so you can quickly understand the details at a glance.

Special wire sizes produced in small lots using in-house die processing

Diameter SpecificationIn-house Die ProcessingSmall-lot Prototyping

Special wire sizes not available from material distributors were produced in small lots using our in-house die processing.

φ0.346mm

±0.002mm

for Precision Springs

Wire diameters specified in 0.001mm increments achieved through in-house die processing.

Challenge: Even after selecting available stock from distributors, the required wire size could not be procured.
Approach: We fabricated a near-size die in-house to match the specified diameter.
Result: The required wire size became available in the exact specified diameter.

Customer Feedback“We were able to order a custom wire size in small lots, even though it wasn't available in market stock. This was a great help.”

Consult on Diameter & Tolerance

Mechanical PropertiesCondition DesignNon-standard Specifications

We produced wire with tensile strength outside JIS standards by designing the drawing and heat-treatment conditions.

φ0.325mm

1,400 N/mm²

Non-standard products

Redesigning reduction ratio and heat-treatment conditions to achieve target tensile strength.

Challenge: The required tensile strength did not match any existing standard values for the intended application.
Approach: We redesigned the reduction ratio in the drawing process and the heat-treatment conditions, then fine-tuned the results through prototyping.
Result: The wire achieved the exact tensile strength specified for the application.

Customer Feedback“We were able to custom-order wire with tensile strength outside standard specifications in small lots. This was extremely helpful.”

Consult on Mechanical Properties

Fine stainless-steel spring wire with minimized surface slip marks

Surface QualityNon-slip Drawing MachinePrecision Spring Applications

We produced fine stainless-steel wire for springs with minimized slip marks on the surface through non-slip drawing.

φ0.155mm

±0.002mm

for Precision Spring Applications

Reducing surface defects through die selection and non-slip drawing.

Challenge: The application required wire with minimal surface scratches.
Approach: We carefully selected the drawing dies and processed the wire using a non-slip drawing machine to reduce surface defects.
Result: The improved wire quality led to customer satisfaction and expanded demand across additional sizes.

Customer Feedback“We used this wire in an application where surface quality is critical, and it achieved a finish very close to what we required.”

Consult on Surface Quality

Fine stainless-steel spring wire supplied on large bobbins

Winding ChangeLarge-Bobbin WindingSpring Applications

We supplied fine stainless-steel wire for springs wound on large bobbins.

φ0.13mm

approx. 7 kgs

DP-15 Bobbin

By selecting a bobbin with a larger barrel diameter, we achieved high-capacity winding of stainless-steel wire for springs (non-coated) with good coil set.

Challenge: The conventional coil (bundle) format resulted in small unit weights per product.
Approach: We selected a bobbin with a larger barrel diameter and ensured proper coil-set characteristics during winding.
Result: The increased wire weight per bobbin enabled longer continuous machine operation and improved production efficiency.

Customer Feedback“The wire works perfectly with our existing equipment, and once we tried it, we found it easy to handle. Attaching and removing the material was simple even when stopping use midway.”

Consult on Bobbin-wound Spring Wire

Soft fine wire with consistent unit weight, delivered in the required number of reels

Length ControlRewinding SupportSmall-lot Winding

We supplied soft fine wire with consistent unit weight (controlled length), delivered in the required number of reels.

SUS316 Soft Bright Annealed

φ0.090mm

approx. 447g × 246 reels

The automatic small-lot rewinding system equalizes the unit weight (controlled length) of each reel.

Challenge: A large number of small-lot bobbins were required for the vertical wires of the mesh.
Approach: Annealed wire wound in large coils was rewound using an automatic small-lot rewinding machine, producing the required number of bobbins according to the preset length counter.
Result: We delivered all bobbins with fully uniform unit weight (controlled length), matching the required quantity.

Customer Feedback“Because every bobbin had consistent unit weight and length, the remaining wire after use was minimal, resulting in almost no material loss.”

Consult on Length and Winding

Micro-indentations added to the wire surface to improve lubricity (MPSR)

Soft Bright Annealed WireSurface ReformingLubricity

Adding multiple micro-indentations to the wire surface improves its lubricity.

SUS304 Soft Bright Annealed

φ0.55mm

12.5KP Bobbin

MPSR (Micro Peen Surface Reforming) treatment was applied to the wire surface.

Challenge: To reduce surface adhesion and improve sliding performance when the wire is used against mating components.
Approach: Friction resistance was reduced by forming multiple micro-indentations on the wire surface through MPSR (Micro Peen Surface Reforming).
Result: Three micro-indentation intensity patterns—Strong, Medium, and Weak—were applied, each producing a corresponding and measurable improvement in sliding behavior.

Customer Feedback“The results were good, but because the process adds cost, we will decide on full adoption after evaluating which level—Strong, Medium, or Weak—is most appropriate.”

Consult on MPSR

Wire breakage during net-making significantly reduced by adjusting lubricant

LubricityBreakage PreventionCustomized Solutions

By adjusting both the type and the application amount of lubricant, wire breakage during net-making was significantly reduced.

Alloy600

φ0.25mm

Knitted Mesh Processing

The type and the application amount of lubricant applied to the wire were adjusted.

Challenge: Depending on the steel grade, some wires are easy to process while others are difficult. During knitted-mesh processing, holes began to appear in the mesh as the wire was knitted.
Approach: The type and application amount of lubricant applied to the wire surface were changed to improve processability. Because certain lubricants were incompatible with standard ABS bobbins, the bobbins were replaced with solvent-resistant ones.
Result: The outcome was favorable; however, the customer later requested a halogen-free lubricant, and additional adjustments are currently underway.

Customer Feedback“Holes no longer appeared during processing, and the needle life was extended. The results were very good.”

Consult about Lubricants

Difficult forming stabilized by a customized lubricant applied to bare wire

LubricityDifficult-to-Process GeometriesCustomized Solutions

A product difficult to form due to insufficient lubricity in the forming process was successfully stabilized by formulating and applying a customized lubricant to the wire.

φ0.45mm

WPB Non-Coated, Bright-finish Hard-drawn

for Precision Springs

The lubricity normally provided by a nickel coating was replaced by applying a formulated lubricant to the bare wire.

Challenge: We needed to produce a demanding forming-process product using wire without a nickel coating, while still maintaining sufficient lubricity for stable forming.
Approach: A specially formulated lubricant was developed in-house to match the excellent lubricity normally provided by nickel coating. The lubricant was applied with controlled coating volume to ensure consistent forming performance.
Result: The forming process achieved satisfactory results; however, degreasing after forming is required.

Customer Feedback“For medical applications where nickel coatings are undesirable, this kind of customized support is extremely helpful.”

Consult about Wire Lubricants

Strengths of Sakai Wire Seen Through Our Case Studies

We devote our best to every single wire.
Our strength lies in providing meticulous support—from prototypes and small-lot production to detailed adjustments in wire diameter, mechanical strength, surface quality, winding configuration, length control, and lubricity.

0.001 mm-level Diameter Precision
Design and Prototyping for Non-Standard Specifications
Proposals that include Supply-Condition Optimization

Frequently Asked Questions

Q1. Can I consult with you even if my conditions are not exactly the same as the case examples?

A. Yes. We can review your request based on the closest available conditions—such as Wire Diameter, Steel Grade, Application, Quantity, and Downstream Processes—and proceed from there.

Q2. Can I consult with you about wire specifications that other companies have declined?

A. Yes. We review the relevant conditions—such as Non-Standard Diameters, Out-of-Spec Tensile Strength, Special Winding Forms, or Specific Length Requirements—and then determine whether we can support your request.

Q3. Is it possible to request 0.001 mm-increment diameter specifications or small-lot prototyping?

A. Depending on the details, yes. We have case examples where we adjusted Wire Diameter through In-house Die Processing, tailoring it to the required Application, Tolerance, and Quantity.

Q4. Can I consult with you about issues such as breakage in downstream processes, or about length and winding requirements?

A. Yes. We have case examples where we optimized Lubricant type and Coating amount, managed Length per Reel, and provided Large-Bobbin Winding, all tailored to the customer's usage conditions.

Contact us

We welcome consultations even before your requirements are fully defined. Please feel free to consult with us about wire specifications rejected by other companies or wires causing issues in downstream processes.

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Case Studies