Maximum velocity for gasoline through an hose?

[Bilodeau]

Hi everyone,

I'm looking to find the maximum velocity that I can have in a hose...Someone has an idea about that?

I have found that the maximum velocity for 8 inches hose is 15 meters/second, but I bet that for gasoline, the velocity must be lower...( presence of electrostatic charge generation)

API or anything else that can help me...?

Thanks you

Ken

 

[stookeyfpe]

API 2021 states that for most refined Class I flammable liquids the flow velocity should not exceed 3 feet/second.

 

[Bilodeau]

hum...I'm not sure about that...

 

[IFRs]

If it is properly grounded, you have enough power, the hose is strong enough, etc - why should there be a limit?

 

[Bilodeau]

Because the maximum velocity will be highest in this section...after the diameter become 10 and 12 inches...

Thanks for your answers...

 

[epoisses]

Just curious... what are you using a 8" hose for? Is it in the middle of a refinery?

 

[Bilodeau]

To discharge the boats...this hose is connected to the discharge of the boat's pump...

 

[owg]

Most gasolines dissipate static charge very quickly, unlike toluene and jet fuels, to name a couple of the bad actors. Hose velocities are also limited by the bends in the hoses so that reaction forces do not exceed the strength of the hose. Check with the hose manufacturer. Sorry I cannot quote a velocity for you.

HAZOP at

http://www.curryhydrocarbons.ca

 

[Bilodeau]

Thanks you!

 

[PAN]

stookeyfpe,

I do not have API 2021 on hand. However, the maximum velocity limit of 3 ft/sec (1 m/s) seems too low for me. I believe that the discharge line of pump always design with higher velocity.

KenBilodeau,
-What is your required flow rate?
-How about the velocity in your line size 10" or 12" in other sections?

 

[Bilodeau]

Hi PAN,

-What is your required flow rate? in the future 1400 m³/hr

-How about the velocity in your line size 10" or 12" in other sections? @1400 m³/hr, we'll get about 17 and 25 ft/sec.

Anyway, I have called the manufacturer and he told me that the "extreme" velocity limit is about 50-60 ft/sec (depend of the standard's indutry). BUT, for security and the hose's lifetime, he recommands a lower velocity, like 35-40 ft/sec.

Ken

 

[PAN]

KenBilodeau,

I assume that you use carbon steel pipe size 10" and 12" in the line. In my limited experience, the velocity 17 to 25 ft/sec will be a cause of high erosion.

Your future flow rate is 1400 m3/hr. How about the current flow rate?

 

[Bilodeau]

Actual: 650 m³/hr

For security and for pressure drop, we don't want exceed 25 ft/sec in normal piping.

A106 - Grade B

 

[PAN]

KenBilodeau,

In my opinion, your current facilities and actual flow should be acceptable.

If you increase flow rate from 650 m3/hr to 1400 m3/hr, you should increase your line size (and hose also). Velocity limit is for rough estimation only, however, I will not recommend to use even 25 ft/sec. This is still high velocity limit for me.