Tension Links
Rigid steel links with configurable oval holes that precisely control mold opening stroke. Available in four configurations — long stroke, stepped, two oval holes, and two oval holes with land — to match single or multi-stage plate control requirements.
Products (4 Series)
Tension Links — Long Stroke
Single Oval Hole | Maximum Travel
Tension Links — Stepped
Two Holes at Different Heights
Tension Links — Two Oval Holes
Two Configurable Oval Holes
Tension Links — Two Oval Holes with Land
Two Holes + Solid Land Section
How to Choose the Right Tension Link Type
Select based on the number of plates you need to control and whether you need intermediate stop positions:
| Criteria | Long Stroke | Stepped | Two Oval Holes | Two Oval + Land |
|---|---|---|---|---|
| Number of Stages | 1 | 2 (different heights) | 2 (same height) | 2 + intermediate stop |
| Stroke Range | Up to 120 mm | Two strokes, each up to 60 mm | Two strokes, each up to 60 mm | Two strokes + land stop |
| Plate Pairs Controlled | 1 pair | 2 pairs (staggered) | 2 pairs (aligned) | 2 pairs with intermediate |
| Best For | Simple two-plate control, maximum stroke | Three-plate molds with different stroke per stage | Three-plate molds with equal stroke per stage | Complex sequence with intermediate stop |
Selection guide: Most three-plate molds use the two-oval-hole type to control both runner separation and main parting stroke. See our How to Choose Between Long Stroke, Stepped, and Dual-Oval Tension Links.
How Oval Hole Stroke Control Works
Stroke Calculation
A tension link's stroke is determined by a simple formula: Available Stroke = Oval Hole Length − Bolt Diameter. When the mold opens, the bolt slides within the oval hole. At the end of travel, the bolt contacts the end of the hole, creating a hard mechanical stop. By selecting oval hole lengths in 5 mm increments, engineers can precisely match the link's stroke to their mold design requirement.
Two-Hole Configuration
In a two-oval-hole tension link, the upper hole controls the first plate pair (e.g., runner plate to cavity plate), and the lower hole controls the second pair (cavity plate to core plate). Each hole can have a different length, allowing independent stroke control for each stage. The "with land" variant adds a solid section between holes that creates an intermediate stop — the first stage completes, then the second stage begins only after the intermediate stop is released.
Design guide: For stroke calculation worksheets and worked examples, see our How to Calculate Tension Link Stroke for Three-Plate Mold Design.
Bolt & Retainer Pairing
Tension Link (any type)
Select by stroke and hole configuration. Width determines bolt diameter.
Tension Link Bolt + Retainer
Dedicated bolt (optional urethane wrap) + single or double flange retainer. See Bolts & Retainers page.
Application Scenarios
Three-Plate Mold Dual-Stage Stroke Control
Standard three-plate mold where runner parting opens 30mm and main parting opens 80mm. Both stages need independent, repeatable stroke limitation.
Why it fits: Two-oval-hole tension link provides independent stroke control for both stages with a single link per mold side.
Long-Travel Single-Stage Opening
Large mold with 100mm+ plate travel where the full opening distance must be precisely controlled to prevent runner damage.
Why it fits: Long stroke configuration provides up to 120mm of controlled travel in a single stage.
Frequently Asked Questions
What is the difference between long stroke, stepped, and two-oval-hole tension links?+
How does the oval hole length determine the mold opening stroke?+
Can I adjust the stroke after installation?+
What material are MISUMI tension links made from?+
Engineering Resources
How to Choose Between Long Stroke, Stepped, and Dual-Oval Tension Links
Configuration comparison with application-specific recommendations for each type.
How to Pair Tension Links with the Right Bolts and Retainers
Compatibility charts and mounting instructions for tension link hardware assemblies.
Need a Custom Quote?
Specify your stroke distance, hole configuration (single/dual/stepped), link width, and quantity. Custom oval hole lengths available in 5mm increments.