Skip to the beginning of the images gallery

Seamless 316 Stainless Steel Tubing, 0.25 Inch OD, 0.04 Inch Thick, 0.18 Inch ID

Description & Features

Constructed from ASTM A269 B90 seamless, bright annealed 316 stainless steel, this tubing measures 0.25 inches in OD, with a wall thickness of 0.04 inches, and an ID of 0.18 inches. It is designed for high-performance environments, providing a burst pressure of 21,000 psi and a maximum working pressure of 3,500 psi, with a safety factor of 6:1.

The tubing's interior area of 0.0254 square inches supports a rated flow capacity of 0.9. With a tensile strength of 75,000 psi, it ensures robustness and reliability across various industrial applications, meeting the demands of sectors requiring high tensile strength and corrosion resistance.

Produced by Marmon/Keystone, it is ideal for critical applications, ensuring both durability and efficiency. Please review important safety and application information related to the proper selection and usage of tubing and tube fittings.

Supplier Part Number: 1/4.035-SS

Specifications

Burst Pressure 21000	Brand Marmon/Keystone	Brand Marmon - Keystone	Pack Size 12.00	UOM FT	I.D. 0.18 in	Inside Area 0.03	Maximum Working Pressure 3500	O.D. 0.25 in	Rated Flow 0.90	Rated Flow 0.9	Safety Factor 6:1	Supplier Part Number 1/4.035-SS	Wall Thickness 0.04	Product Weight 0.21 lbs

Similar Products

Model Number	O.D.	Wall Thickness	I.D.	Inside Area	Rated Flow	Maximum Working Pressure	Burst Pressure	Safety Factor
1/2.049-SS Seamless 316 Stainless Tubing	0.5 in	0.049	0.402 in	0.1269	6	2450	14700	6:1
1/4.049-SS Seamless 316 Stainless Tubing	0.25 in	0.049	0.152 in	0.0181	0.7	4900	29400	6:1
.750X.065-316SS-SML Seamless 316 Stainless Tubing	0.75 in	0.065	0.62 in	0.3018	12	2167	13000	6:1
3/8.049-SS Seamless 316 Stainless Tubing	0.375 in	0.049	0.277 in	0.0602	2.8	3267	19600	6:1
5/8.065-SS Seamless 316 Stainless Tubing	0.5625 in	0.065	0.4325 in	0.1923	9	2600	15600	6:1
1-1/4.120-SS Seamless 316 Stainless Tubing	1.25 in	0.12	1.01 in	0.8008	36.7	2400	14400	6:1
1.00X.109-316SS-SML Seamless 316 Stainless Tubing	1 in	0.109	0.788 in	0.4801	22	2725	16350	6:1
.500X.065-316SS-SML Seamless 316 Stainless Tubing	0.5 in	0.065	0.37 in	0.1075	4.9	3250	19500	6:1
3/16.035-SS Seamless 316 Stainless Tubing	0.1875 in	0.035	0.1175 in	0.0108	0.4	4667	28000	6:1
3/4.095-SS Seamless 316 Stainless Tubing	0.75 in	0.095	0.56 in	0.2462	11.1	3167	19000	6:1
3/8.035-SS Seamless 316 Stainless Tubing	0.375 in	0.035	0.305 in	0.0731	3.4	2333	14000	6:1

Product Questions & Answers (5)

Question by: Dustin Y on Mar 13, 2026, 3:18 PM

got a hydraulic setup running pretty high pressure right now. whats the maximum working limit on this quarter inch tubing before it gives out?

Answer by: Customer Support on Mar 15, 2026, 12:42 PM

Based on a 6:1 safety factor, the maximum working pressure is 3500 psi. The actual burst pressure sits much higher at 21,000 psi, but staying at or below the 3500 mark ensures safe continuous operation.

Question by: Ralph M on Mar 22, 2026, 6:28 PM

i got tubing that’s a quarter inch outside, is this the same size and what’s the inside hole on it

Answer by: Customer Support on Mar 24, 2026, 9:37 AM

For sizing, it has a 0.25 inch outside diameter with a 0.035 inch wall, which puts the inside diameter at 0.18 inch.

Question by: Randy A on Apr 3, 2025, 7:45 AM

what's the max working pressure on this 1/4 inch stainless tubing, and is that number already accounting for shock loads?

Answer by: Customer Support on Apr 5, 2025, 6:40 AM

At a 6:1 safety factor, the working pressure comes out to 3,500 psi. That safety factor is specifically intended for situations where considerable hydraulic shock and mechanical strain are present. If your application runs into more severe shock conditions, a higher safety factor of 8:1 should be applied, which would bring the working pressure down below that 3,500 psi figure. On the flip side, if shock and strain are minimal, a 4:1 safety factor can be carefully considered, which opens up higher working pressures. The 3,500 psi rating is not the ceiling in all cases, it is the middle-ground figure built around moderate real-world conditions.

Question by: Norm R on Apr 8, 2025, 1:14 PM

trying to match up some stainless tube i’ve already got, what are the actual dimensions on this one?

Answer by: Customer Support on Apr 9, 2025, 8:18 PM

For sizing, it is 0.25 inch outside diameter with a 0.04 inch wall and a 0.18 inch inside diameter.

Question by: Hubert P on Jan 18, 2026, 7:38 PM

What's the highest pressure this tubing can handle before it bursts?

Answer by: Customer Support on Jan 20, 2026, 6:10 AM

Based on the Barlow formula, this tubing has a burst pressure of 21,000 psi.