If you buy stainless steel pipes, the schedule number is the first thing to check. It tells you the wall thickness, which changes how much pressure the pipe can handle and how much it costs. The common ones for stainless are 10S, 40S, and 80S. Here is how to pick the right one for your job in 2026, based on real data from current charts.
What Does Schedule Mean for Stainless Pipes?
Schedule, or SCH, shows the wall thickness of the pipe. For stainless steel, it ends with S, like 10S or 40S. This is because stainless pipes have thinner walls than carbon steel pipes with the same schedule number. The reason is stainless steel is stronger, so it needs less material to hold the same pressure.
All schedules have the same outside diameter for a given size, but thicker walls mean smaller inside diameter. This affects flow rate. Pressure ratings go up with thicker walls. Always match the schedule to your needs – too thin and it might burst; too thick and you pay extra for no reason.
Key Differences in Wall Thickness and Weight
The main difference is wall thickness. Here is a table for common sizes based on standard charts.
| Pipe Size | Schedule | Wall Thickness (inches) | Weight per Foot (lbs) |
|---|---|---|---|
| 1/2″ | 10S | 0.065 | 0.538 |
| 40S | 0.109 | 0.851 | |
| 80S | 0.147 | 1.088 | |
| 1″ | 10S | 0.065 | 0.868 |
| 40S | 0.133 | 1.679 | |
| 80S | 0.179 | 2.172 | |
| 2″ | 10S | 0.065 | 1.604 |
| 40S | 0.154 | 3.653 | |
| 80S | 0.218 | 5.002 | |
| 4″ | 10S | 0.083 | 3.915 |
| 40S | 0.237 | 10.79 | |
| 80S | 0.337 | 14.98 |
As you see, 10S is the thinnest and lightest. 80S is the thickest and heaviest. For bigger pipes like 6-inch, the pattern is the same – 10S wall around 0.109 inches, 40S 0.280 inches, 80S 0.432 inches.
Thicker pipes weigh more, so shipping costs go up. But they last longer in tough spots.
Pressure Ratings Comparison
Pressure rating is why most people pick a schedule. It shows how much internal pressure the pipe can take before it bursts. Here are burst pressures from standard calculations using 70,000 PSI strength for stainless.
| Pipe Size | Schedule | Burst Pressure (PSI) |
|---|---|---|
| 1/2″ | 10S | 13,481 |
| 40S | 22,607 | |
| 80S | 30,488 | |
| 1″ | 10S | 6,920 |
| 40S | 14,160 | |
| 80S | 19,057 | |
| 2″ | 10S | 3,832 |
| 40S | 9,078 | |
| 80S | 12,851 | |
| 4″ | 10S | 2,582 |
| 40S | 7,373 | |
| 80S | 10,484 |
Note: These are burst pressures. For safe use, apply a safety factor of 4 or 5, so working pressure is much lower. For example, 1/2-inch 10S might work at 2,000–3,000 PSI safely.
10S handles low pressure best. 40S is good for medium. 80S takes high pressure without problems.
Cost Differences in 2026
Prices change with thickness because more material means higher cost. In 2026, expect these averages per foot for 304 stainless (add 20–30% for 316).
- 10S: $2–$5 per foot for small sizes
- 40S: $3–$7 per foot
- 80S: $4–$10 per foot
For a 20-foot length of 2-inch pipe:
- 10S around $60–$100
- 40S $100–$140
- 80S $140–$200
Bigger pipes cost more. Welded is 10–20% cheaper than seamless. Buy in bulk to save 15–25%. Prices might rise 5–8% in 2026 due to raw material costs like nickel.
Common Applications for Each Schedule
Pick based on your job.
10S: Use for low-pressure lines. Good for water supply, gas distribution, HVAC systems, and food processing where flow is key but pressure is low. Example: A dairy plant uses 10S for milk lines because it’s light and easy to clean.
40S: This is the go-to for most jobs. Handles medium pressure well. Common in plumbing, industrial water systems, chemical transfer, and structural supports. Example: A factory might use 40S for compressed air lines since it balances cost and strength.
80S: Best for high-pressure spots. Ideal for hydraulic systems, oil and gas lines, boilers, and chemical plants with corrosive fluids. Example: An offshore platform uses 80S for seawater pipes because it stands up to high pressure and salt.
If your system has high temperature, thicker walls help too.
When to Choose Each One (Decision Guide)
Ask these questions:
- What pressure does your system run? Low (under 1,000 PSI) → 10S. Medium (1,000–3,000 PSI) → 40S. High (over 3,000 PSI) → 80S.
- How much flow do you need? Thinner walls mean bigger inside diameter and better flow. Pick 10S if flow matters more than pressure.
- What is the environment? Corrosive or hot? Go thicker like 80S for safety.
- Budget tight? Start with 10S or 40S to save money.
- Pipe size big? Thicker schedules add a lot of weight, so check transport costs.
Always check codes like ASME B31.3 for your industry.
Other Factors to Consider
Grade matters too. 304 is cheap for general use. 316 for chemicals or salt water. Length: Standard 20 feet, but custom cuts cost extra.
Finish: Polished for food, plain for industrial. Test certificates: Ask for MTC 3.1 to confirm quality.
Shipping: From China, add 15–25% for freight and duties.
If you buy from overseas, sites like hnyasco.com offer good options with stock ready.
Final Thoughts
Choosing between 10S, 40S, and 80S comes down to pressure, cost, and your job. 10S saves money for easy tasks. 40S works for most. 80S handles the tough stuff. Measure your needs first, then pick. For affordable China stainless steel pipe, check reliable suppliers to get the best deal in 2026.