What Is Temper Passed Steel and Why Flatness Matters
In modern steel fabrication, precision flatness and surface consistency are essential for performance, especially in applications requiring laser cutting, forming, or tight tolerances. One critical process that helps meet these demands is temper passing a final cold rolling step that improves steel’s flatness, uniformity, and surface quality.
At Olympic Steel, we offer temper passed steel as part of our processing services to ensure material that meets or exceeds flatness-critical requirements. This blog will explore what temper passed steel is, why flatness matters, and where these benefits make the biggest impact across industries.
What Is Temper Passed Steel?
Temper passed steel also referred to as skin passed or pinch passed steel is cold rolled steel that has undergone a light reduction in thickness through a temper mill. The goal isn’t to significantly change thickness, but rather to enhance flatness and surface uniformity.
This processing step occurs after the initial cold rolling stage and before final finishing. During temper passing, steel is passed between two work rolls under light pressure (typically around 0.5–2% reduction), eliminating residual shape imperfections and improving dimensional consistency.
Key outcomes of temper passing:
- Minimizes coil memory and yield point elongation
- Reduces waviness and internal stress
- Improves surface smoothness and consistency
- Provides more uniform thickness
- Enhances laser and press brake performance
In short, temper passing gives fabricators a flatter, more predictable material - one that performs better in downstream processes.
Why Flatness Matters in Fabrication
Steel flatness refers to how evenly a sheet or plate lies in a single plane, without bowing, twisting, or edge camber. For applications involving:
- Laser cutting
- Robotic welding
- Brake forming or press brake bending
- Sheet metal fabrication
- Panel or enclosure assembly
Flatness is a key factor in achieving accuracy, repeatability, and process speed.
Poor flatness can cause:
- Misalignment in automated welding or assembly
- Laser focus disruption and cutting errors
- Extra labor to flatten or rework parts
- Waste due to scrap or off-spec pieces
When steel is not flat, operations slow down and parts may fail to meet spec. That’s why Olympic Steel prioritizes flatness-critical processing, including temper passing, for customers across the U.S.
How Temper Passing Improves Flatness
Unlike tension leveling or stretcher leveling, temper passing uses cold rolling to achieve flatness and suppress yield point elongation (YPE) - a phenomenon that causes fluting or stretcher strains in forming.
Temper passed steel:
- Lays flatter on laser tables and press brakes
- Forms more predictably during bending or drawing
- Minimizes warping during thermal cutting
These properties reduce variability in multi-part runs and improve first-pass yield. Olympic Steel provides temper passed material in gauges ranging from light cold rolled sheet to heavier coated products.
Typical Flatness Gains from Temper Pass Processing
The following table highlights common flatness ranges before and after temper passing:
| Steel Type | Before Temper Pass | After Temper Pass |
|---|---|---|
| Cold Rolled Sheet | 3/8" to 1/2" deviation in 72" | 1/8" or less deviation |
| Galvanized or Coated Coil | 1/4" to 3/8" variation | 1/16" to 1/8" variation |
| Pre-painted Steel | Slight ripple | Smooth surface, laser-ready |
Olympic Steel’s investment in precision processing lines means customers receive steel that stays flat from delivery through fabrication.
Applications That Require Temper Passed Steel
Many industries and fabrication operations rely on steel that is flat, consistent, and ready to work. Olympic Steel provides temper passed products for:
- OEMs using automated laser or robotic systems
- Agricultural implement manufacturers
- HVAC enclosure and duct fabricators
- Automotive and heavy equipment part suppliers
- Appliance and electrical housing producers
Whether the goal is tight bending radii, clean part nesting, or dimensional accuracy, temper passed steel delivers results.
How Olympic Steel Delivers Flat, Reliable Steel
Olympic Steel has one of the industry’s most comprehensive processing networks for value-added flat rolled steel. Our temper pass capabilities are part of an integrated offering that includes:
- Cold Rolled, Galvanized, and Coated Steel Inventory
- Advanced Leveling (Stretcher + Tension)
- Slitting, Shearing, and Blanking
- Custom Packaging and Logistics
Our temper mills are strategically located to serve customers across the U.S., with consistent quality and short lead times.
We also support laser flat programs where tolerances demand even tighter flatness than industry standards. In combination with our cutting, kitting, and inventory solutions, temper passed steel becomes a critical part of a ready-to-use supply chain.
FAQs: Temper Passed Steel
Is temper passed steel the same as tension leveled steel?
Not exactly. Temper passing uses compression from rollers to improve flatness and suppress YPE. Tension leveling stretches the sheet to remove internal stress. Both improve flatness but work differently.
What industries benefit most from temper passed steel?
Laser cutting shops, press brake operations, panel fabricators, appliance manufacturers, and anyone needing formable, stable sheet.
Can galvanized steel be temper passed?
Yes. Olympic Steel provides temper passing for galvanized and coated products to reduce surface rippling and waviness.
Does temper passing affect steel strength or hardness?
Minimal. It slightly increases yield strength and eliminates fluting, but it is not a heat treatment or hardening process.
What tolerances can Olympic Steel meet?
We can exceed ASTM flatness guidelines depending on grade and gauge. Laser flat tolerances are available upon request.
Final Thoughts
In high-precision fabrication, material consistency matters. Temper passed steel plays a vital role in eliminating shape irregularities and ensuring clean, reliable parts cut after cut, bend after bend.
With Olympic Steel’s national temper passing capabilities, customers receive not only flat material, but flatness tailored to their application needs. Whether you’re making enclosures, agricultural attachments, or precision subassemblies, we help you build better, faster, and with fewer rejects.
Talk to our team to explore how temper passed sheet can improve your fabrication flow and end-product quality.
