Mold Die Coil Springs Medium Duty Compression Spring Ratio 62% 12mm x 6mm Red TM

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Mold Die Coil Springs Medium Duty Compression Spring Ratio 62% 12mm x 6mm Red TM

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OD x ID（mm）: 12 x 6 mm

Length（MM）: 20mm

QTY(pcs): 1 Pcs

Price:

$4.15 USD

Stock:

In stock (500 units), ready to be shipped

Quantity:

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12mm x 6mm Medium Duty Compression Spring — Reliable Force for Mold & Die Applications

When your injection mold, stamping die, or precision fixture demands consistent, repeatable spring force, a mismatched or worn-out spring becomes a costly bottleneck. Engineers and toolmakers who work with tight-tolerance tooling need a medium duty compression spring that delivers a predictable 62% deflection ratio without fatigue failure. This red-coded mold die coil spring is engineered for exactly that environment.

Each spring features an outer diameter (OD) of 12mm (~0.47 in) and an inner diameter (ID) of 6mm (~0.24 in), with free lengths available from 20mm (~0.79 in) to 100mm (~3.94 in). The coil body is wound from high-grade spring steel with a consistent pitch, and the red color coding identifies the medium duty load class at a glance on the shop floor.

Typical use cases include injection mold stripper plate return, progressive die lifter springs for sheet metal stamping, and precision fixture clamping in CNC machining centers — all scenarios where a reliable medium duty compression spring with a 62% deflection ratio reduces downtime and maintains part quality.

⚙️ Compatibility: Fits standard 12mm OD spring pockets. Compatible with ISO 10243 / JIS B 5012 medium duty (red) spring pocket dimensions. Verify free length and pocket depth before ordering.

✅ Key Features of These Medium Duty Mold Die Compression Springs

🔴

Red Color-Coded Medium Duty

Industry-standard red coding instantly identifies the medium duty load class, simplifying spring selection and replacement on the shop floor.

📐

62% Deflection Ratio

A 62% maximum deflection ratio provides a balanced range of working stroke and spring force, suitable for stripper plates, lifters, and clamping mechanisms.

🔩

12mm OD × 6mm ID

Precise outer and inner diameter tolerances ensure a snug fit in standard 12mm spring pockets and reliable guidance over 6mm guide pins.

📏

Multiple Free Lengths Available

Choose from 20mm to 100mm free lengths (15 options) to match your specific mold or die pocket depth without custom fabrication.

🛡️

High-Grade Spring Steel Construction

Wound from high-grade spring steel with consistent coil pitch and ground ends for stable seating and uniform load distribution across the full stroke.

📦

Flexible Pack Quantities

Available in 1, 2, 6, 10, and 20-piece packs — order a single replacement or stock up for production tooling maintenance at a lower per-unit cost.

📐 Technical Specifications — Medium Duty Compression Spring

Outer Diameter (OD)	12mm (0.47 in)
Inner Diameter (ID)	6mm (0.24 in)
Wire Diameter	Typically 2.5–3mm (see variant options)
Free Length	20mm – 100mm (0.79 in – 3.94 in), see variant options
Deflection Ratio	62% (medium duty)
Load Class / Color Code	Medium Duty — Red
Material	High-grade spring steel
End Type	Closed & ground ends
Spring Rate	See variant options
Standard Reference	ISO 10243 / JIS B 5012 (medium duty)
Pack Quantity	1 / 2 / 6 / 10 / 20 pcs (see variant options)

❓ Frequently Asked Questions

How do I choose the correct free length for my mold?

Measure the spring pocket depth in your mold or die. The free length of the spring should be longer than the pocket depth by the amount of working stroke you need. As a general rule, do not exceed 62% of the free length as your working deflection for medium duty springs. Select the next standard length up if your calculated free length falls between two options.

What does the 62% deflection ratio mean in practice?

The 62% deflection ratio means the spring can be safely compressed to 62% of its free length under maximum load without permanent set or fatigue failure. For example, a 50mm free-length spring can be deflected up to approximately 31mm during operation. Exceeding this ratio will shorten the spring's service life.

Is this spring compatible with standard mold spring pockets?

Yes. The 12mm OD and 6mm ID dimensions conform to ISO 10243 and JIS B 5012 medium duty (red) spring standards, which are widely used in injection mold and stamping die design. Always verify your pocket diameter and guide pin diameter against these dimensions before installation.

How does the red color coding help on the shop floor?

The red color identifies the medium duty load class at a glance, following the international mold spring color coding convention: light duty = yellow, medium duty = red, heavy duty = blue, extra heavy duty = green. This prevents accidental substitution of incorrect load-class springs during maintenance.

Can these springs be used in corrosive or high-humidity environments?

These springs are made from high-grade spring steel, which offers good mechanical properties but limited inherent corrosion resistance. For humid or mildly corrosive environments, consider applying a light machine oil coating during storage and installation. For highly corrosive environments, contact us to confirm material options.

What quantity should I order for a production mold?

For a single mold, count the number of spring pockets requiring this size and order that quantity plus 10–20% as spares for preventive maintenance. The 6-pack, 10-pack, and 20-pack options offer a lower per-unit cost and are well-suited for toolroom stock. Single-piece packs are ideal for prototyping or one-off replacements.

How do I verify the spring rate for my load calculation?

Spring rate varies by free length — shorter springs of the same OD/ID/wire diameter will have a higher rate than longer ones. Refer to the ISO 10243 or JIS B 5012 standard tables for the specific spring rate of each free length, or contact us with your load and stroke requirements for a recommendation.

🛒 Select your OD x ID and free length above, then add to cart.