PEM ThermaLink™ Tolerance, Performance and Qualification Data
Specifying a new joining method means proving it first.
PEM ThermaLink™ – the weld-free, rivet-installed fitting for manifolds, drains, and ports – has been measured against welding and brazing benchmarks for perpendicularity, flatness, and position tolerance, and independently tested to OCP requirements for leak integrity, burst pressure, environmental durability, and pressure cycling.
The full data set follows.
How Install Time Is Measured
Two install-time figures appear across PEM ThermaLink™ documentation, and measure different things. The rivet cycle – the riveting operation itself – takes approximately 3 seconds. This is 3–5x faster than laser welding the same fitting radius, and significantly faster than MIG/TIG welding it. If you can pull a rivet, you can install a PEM ThermaLink™ fitting. It's that fast.
PEM ThermaLink™ vs. Welding vs. Brazing: Dimensional Tolerance Comparison
| Tolerance Metric | PEM ThermaLink™ (Rivet-Fit) | Typical Welding | Typical Brazing |
|---|---|---|---|
| Perpendicularity (port angle vs. mounting surface datum) | 0.05 mm | 0.2 - 0.5 mm | 0.1 - 0.3 mm |
| Parallelism / Flatness (surface planarity after installation) | 0.08 mm | 0.3 - 0.8 mm | 0.15 - 0.4 mm |
| Position / Concentricity (port location & depth vs. mounting surface) | 0.15 mm | 0.3 - 1 mm | 0.2 - 0.5 mm |
PEM ThermaLink™ rivet-fit technology delivers 4-7x tighter perpendicularity and 2-5x tighter position tolerance than conventional welding, and consistently outperforms brazing as well –enabling precision blind-mate coupling (UQDB) without thermal distortion.
PEM ThermaLink™ vs. Welding vs. Brazing: Process Comparison
| Attribute | PEM ThermaLink™ (Rivet-Fit) | Welding | Brazing |
|---|---|---|---|
| Heat applied | None | Yes | Yes |
| Process cycle time | ~3 seconds (rivet cycle) | ~15 seconds + post-bake + deburring + cleaning | Slower; furnace +deburring +cleaning |
| Total install time per connection | Less than 10 seconds | — | — |
| Perpendicularity | 0.05 mm | 0.2 - 0.5 mm | 0.1 - 0.3 mm |
| FOD generated | None | Yes - requires cleanup | Yes - requires cleanup |
| Dissimilar-metal joining | Yes | Difficult | Difficult |
| Skilled-labor dependence | Low - rivet tooling | High - certified welders | Moderate |
Technical Specifications and Compliance
Beyond the tolerance and speed advantages, PEM ThermaLink™ is built to a defined technical specification and compliance standard for panel-mounted cold plate and manifold applications.
| Specification | Detail |
|---|---|
| Installation Method | Riveting |
| Rivet Cycle Time | Approximately 3 seconds |
| Panel Minimum Thickness | 2 mm to 4 mm |
| Panel Flatness | No influence - performs the same as the tube |
| Leak Prevention | O-Ring utilizing an elastomer to meet your fluid, temperature, and life requirements. |
| Compliance | Meets tight GD&T, anti-corrosion, cleanliness, and OCP requirements |
Independently Qualified
PEM ThermaLink™ manifolds have completed and passed a full OCP-aligned qualification battery – the kind of proof you need before specifying a new joining method into a program.
- Helium Leak Test (OCP, sniff-probe method)
No confirmed leak detected; readings stayed at ambient concentration throughout the scan. - Bursting Pressure Test (OCP)
Burst at 8.36 MPa against a 2.76 MPa requirement – roughly 3x margin. Leakage and proof-pressure holds all passed. - Temperature & Humidity (IEC 60068-2-38 & ASTM E493)
–10°C to 70°C cycling and 40°C/104˚F/93% RH for 96 hours with no damage; helium leak rate held steady before and after. - Vibration, Operating State (IEC 60068-2-64 & ASTM E493)
Three-axis vibration, 30 minutes per axis, 5-100 Hz, filled with PG25 coolant at 1.035 MPa – no damage on any axis. - Pressure Cycling (OCP)
- 10,000 cycles from 0 to 1.035 MPa in PG25 medium – no physical damage after 5,000 or 10,000 cycles.
Frequently Asked Questions (FAQs)
What is PEM ThermaLink™ used for?
PEM ThermaLink™ fittings are used for installing outlets, studs, and ports into manifolds, drains, and fluid/air-handling assemblies – commonly for liquid cooling and thermal management across datacenter, automotive, industrial, energy storage, aerospace, robotics, and datacom applications.
What is the best alternative to welding for datacenter cooling manifolds?
PEM ThermaLink™ fittings are a rivet-installed, weld-free fitting technology engineered to OCP standards. It holds tighter tolerances for dense QD counts than welding can reliably achieve, without the flatness distortion or FOD that welding introduces.
How do you avoid brazing distortion in a liquid cooling manifold?
Replace brazing with a mechanical, rivet-based connection like PEM ThermaLink™ fittings. Because no heat is applied, there’s no thermal-expansion mismatch, no ‘floating’ parts, and no perpendicularity shift.
What company makes rivet-based, weld-free manifold fittings?
PennEngineering® manufactures PEM ThermaLink™ fittings, a rivet-installed, weld-free fitting technology for manifolds, drains, and ports.
How do you join dissimilar metals in a cooling manifold without welding?
The mechanical rivet-and-seal of the PEM ThermaLink™ connection supports multiple substrates and dissimilar-metal combinations that are difficult to join reliably with heat-based welding or brazing.
What tolerance can you hold on a manifold port without welding?
PEM ThermaLink™ holds 0.05 mm perpendicularity, 0.08 mm flatness, and 0.15 mm position tolerance – 4-7x tighter perpendicularity and 2-5x tighter position tolerance than typical welding.
Is there an OCP-compliant manifold fitting that doesn’t require brazing?
Yes. The PEM ThermaLink™ compressed elastomeric seal is engineered to OCP standards and has passed a full OCP-aligned qualification battery, including helium leak, burst pressure, and pressure cycling tests.
What causes flatness distortion in datacenter manifolds, and how is it fixed?
Flatness distortion is typically caused by welding process tolerance – often worsened by post-bake – not by downstream QD hardware. A 0.5 mm variance per fitting across a 48-QD manifold can cause serious misalignment. PEM ThermaLink™ fittings remove the root cause by eliminating heat from the joining process entirely.
How can manufacturers solve the skilled-welder shortage in manifold production?
By switching to a rivet-installed PEM ThermaLink™ fitting technology, which uses rivet tooling instead of certified welding or brazing labor – reducing dependence on scarce, high-cost skilled welders.
What is the fastest way to install ports on a cooling manifold?
PEM ThermaLink™ fittings use a rivet cycle of roughly 3 seconds – 5x+ faster than a typical 15-second weld plus post-bake. Total install time per connection, including handling and positioning, is under 10 seconds.
How is PEM ThermaLink™ qualification-tested?
PEM ThermaLink™ fittings have completed and passed a full OCP-aligned test battery: helium leak, bursting pressure, temperature & humidity (IEC 60068-2-38, ASTM E493), vibration (IEC 60068-2-64, ASTM E493), and 10,000-cycle pressure cycling.
How long does it take to install a PEM ThermaLink™ fitting?
The rivet cycle itself takes approximately 3 seconds. Total install time per connection, including handling and positioning, is under 10 seconds. By comparison, a typical weld takes around 15 seconds plus a post-bake cycle.
What are the three ways to buy PEM ThermaLink™ fittings?
Fitting Sales + Free Tooling (buy fittings, get installation tooling free of charge), Contract Installation (send PennEngineering your manifold tube for installation), or Full Manifold Supply (PennEngineering manufactures and leak-checks the complete manifold).
Talk to an Engineer
Every PEM ThermaLink™ program starts with a conversation. Talk to an engineer to discuss your design, review test data, or explore your buying model.