A Refresher On Pumping: Drafting

[x635 4,066]

I'm just trying to keep my skill levels up, and I must admit, coming from districts with 100% high pressure hydrants, and only drafting in Probie School, I've forgotten how to start and maintain a draft for waterflow, and I can't seem to find my pump operations book right now.

Can anyone give me a quick, concise refresher here on the steps of drafting?

[jcoppola 52]

Pull up to the water source, with the midline of the pump no more than 20' above the surface of the water. Ensure the pump fittings are all extremely tight. Hook up the hard suction to the intake side of the pump and the next length of hard suction on dry ground with a rope attached to the strainer. Using a roof or straight ladder, lower the suction hose into the water so that the strainer is completely covered by a few inches of water. Engage the pump on the engine. Throttle up a bit and begin to prime the pump. The primer pump is the only one that will pump and displace air, so while it is working, it will wind loudly. Once you hear water beginning to enter the hard suction hose, gradually pull a discharge to get water flowing, a deck gun works really good for this purpose and is usually what you will be feeding at a big fire. Rules of thumb - don't open your tank fill valve, as you don't want murky water in the tank. No more than 30' of lift is possible theoretically, so stick close to 20' if you can help it. Watch the ground near the draft site, you don't want to lose your pumper in the water source, use a beach ball near the strainer in shallow water to prevent a water funnel or whirlpool effect, that will introduce air into your operation and that may cause you to lose your prime. Once you are done drafting, flush the pump with clean water and fill the priming fluid reservouir.

Drafting is fun, we hardly do it in Norwalk, but we refresh the skills time and again.

Joe

[mfc2257 464]

While we're doing a refresher here.... Lets go over how this really works. Many people believe that the intake side of the pump is actually sucking water in. That's not the case. At draft, when you are priming the pump, you are actually reducing pressure inside the pump so that it is lower than atmospheric pressure. Once you have accomplished this, what is actually forcing the water up the hard suction is atmospheric pressure pushing downward on your static water source and it naturally moving to an area of lower pressure which is inside the pump housing. Once inside the pump housing the impeller(s) boost pressure and send it into a discharge.

[Bnechis 3,961]

You have to also watch the water level in your static source. During a fire in 1984 on premium point, NRFD was drafting out of Long Island Sound and we dropped the water level down 8 -10' and loss the source. It took 6 hours for the water level to come back up.

Amazing that one pumper can pump that much water that it drop's the water level of LIS

We now have an acroynm for this: T.I.D.E.

[firemoose827 324]

You have to also watch the water level in your static source. During a fire in 1984 on premium point, NRFD was drafting out of Long Island Sound and we dropped the water level down 8 -10' and loss the source. It took 6 hours for the water level to come back up.

Amazing that one pumper can pump that much water that it drop's the water level of LIS

We now have an acroynm for this: T.I.D.E.

What is the breakdown of the acronym T.I.D.E? Im curious!!

Also, great posts here so far guys. Excellent points made about drafting, In an area without too many hydrants I can work with drafting on a weekly basis, and all of the info posted so far is great.

Excellent Topic.

[mfc2257 464]

What is the breakdown of the acronym T.I.D.E? Im curious!!

Total

Idiot

Driving

Engine

JUST KIDDING !

[Bnechis 3,961]

Total

Idiot

Driving

Engine

JUST KIDDING !

Call 911....I've fallen and can't get up................ROFLMAO

Tide is something those of us on the coast get, every 6 hours the sound fills or empty's, regardless of what the FD does. and those who don't deal with it often, forget that from school days.

[ny10570 745]

You have to also watch the water level in your static source. During a fire in 1984 on premium point, NRFD was drafting out of Long Island Sound and we dropped the water level down 8 -10' and loss the source. It took 6 hours for the water level to come back up.

Amazing that one pumper can pump that much water that it drop's the water level of LIS

We now have an acroynm for this: T.I.D.E.

Similar problem for EMS in the 5 boroughs. Over the years more than a couple of units have been sitting available when without warning the beach begins to shrink and a unit suddenly finds themselves amphibious.

[x635 4,066]

Thanks guys! I feel refreshed, lol! I really appreciate the knowledge you all shared....even learned some things I didn't know.

In regards to salt water, besides flushing the pump, is there any other maintainence that would need to be done after drafting salt water due to its corrosive properties?

Any other tips or tricks...keep 'em coming!!

[Bnechis 3,961]

Thanks guys! I feel refreshed, lol! I really appreciate the knowledge you all shared....even learned some things I didn't know.

In regards to salt water, besides flushing the pump, is there any other maintainence that would need to be done after drafting salt water due to its corrosive properties?

Any other tips or tricks...keep 'em coming!!

Remove the fish parts, clams and other life from the screen

[grumpyff 1,159]

As mentioned before, make sure all connections are TIGHT. You will here air sucking through if they are not tight, or have damaged washers. Also make sure everything on the pump is closed (drains,discharges) while priming the pump. In the last year I have learned a lot about drafting, our district has no hydrants, as opposed to my old department which utilized hydrants, and drafted once or twice a year during drills. I like the floating strainers with the flexible hard suction, no more tying off to a ladder.

Here is a photo of a whirlpool created while drafting out of a portable pond (tanker operations) with a flat bottom strainer:

[Grumpy 1]

Enjoyed the thread. Been retired over 10 yrs. now, but I think that's the first time I heard the beach ball tip mentioned. Makes good sense for certain conditions, but in Westchester I never heard a call for MA like: Request XXXXX FD for their rescue with the beach ball.

[jack10562 414]

Most newer pumps today are single-stage, but I bet there are still a bunch of two-stage pump equipped engines in service out there.

In the case of a two-stage pump, it's recommended to engage the pump in Volume (parallel), that way both pump impellers are directed to the suction inlet.

Close all inlet and outlet gates, (and drains) put it "in pump", and Rev the engine to around a grand, hit the primer and you should see pressure within around 30 seconds. If not, check all your suction connections, take a look-see that you have oil in the primer reservoir.

I did see NRFD drafting in a parking lot at a water main break, not too long ago... good drill!

[Guest alsfirefighter]

Great points so far...nice to see you've forgotten what I taught you already 635...

Seth brings up a great point that it never hurts no matter how good you think your water system is to practice drafting.

A couple of other things to point out...

1. It is recommended that you have 24 square inches of water around your intake.

2. If you can hook hard suction to it, you can draft it at the same time. You can often significantly increase the volume delivery of your pump by adding additional hard suctions to other intakes...including the 2 1/2" inlets.

3. Strainers and other adapters (like the one pictured) = reduced GPM. If you need volume and if you can...get rid of them.

4. In conjunction with the above...drafting off your front intake will also reduce available GPM due to the bends in the pipe going to the pump. Your side steamers are straight into the pump and much shorter.

5. Stretch a short section of 1 3/4" with a nozzle on it and secure it. I've lost one to many drafts and have seen others struggle in the field and in conduction pump ops courses when trying to open the deck gun to keep water flowing. A normal discharge gives you a finer control with opening it slowly and to keep water moving once the draft is established.

6. Just as some mentioned the tide can go out...but remember it can also come in! Before you know it the front bumper can be underwater.

7. Anything that floats can help with whirlpools. I first saw the beach ball trick when I was in my Virginia department and really didn't know what to think about it when I first saw it and until someone explained the whole concept. Also made for some interesting looks from the public.

Finally...FILL YOUR BOOSTER TANK IF NEEDED! You can flush it out later...but that is water you may need if you lose the draft or if you are a source pumper and the dump site isn't holding up. This is basically your crews escape water and every bit counts!

If youw ant more info on drafting, rural water supply and moving big water, Larry Davis has excellent articles in Fire Rescue Magazine...to be honest that is the only thing I've ever really read or enjoyed in that particular publication is the water supply articles...they had a fantastic series of articles dealing with LDH last year as well.

[antiquefirelt 994]

I'll toss in a note about tightening hard suctions. If you maintain hand tight and no one beats it on with the mallet, hand tight will work. Once someone has put the mallet to any fitting the O-ring gets compressed and always needs to be just a little tighter. My previous FD was a draft only town and we could maintain hand tight suction for over a year when everyone understood to leave the mallet in the compartment. We also used beachballs, small mooring balls, a chunk of Blue board or even wood to break up the whirl pools in portable tanks. Often when you can't get a prime you need to look for that on bad valve that needs to be just so or tighten a cap. The box type strainers work the best to give you max flow, as the barrel types tend to pick up debris easy. Low level strainers are good in drop tanks, but the box strainer (right side up) works better as long as the tankers are on a decent rotation.

[jcoppola 52]

Most newer pumps today are single-stage, but I bet there are still a bunch of two-stage pump equipped engines in service out there.

In the case of a two-stage pump, it's recommended to engage the pump in Volume (parallel), that way both pump impellers are directed to the suction inlet.

Close all inlet and outlet gates, (and drains) put it "in pump", and Rev the engine to around a grand, hit the primer and you should see pressure within around 30 seconds. If not, check all your suction connections, take a look-see that you have oil in the primer reservoir.

I did see NRFD drafting in a parking lot at a water main break, not too long ago... good drill!

Great point about the 2 stage pump. Forgot all about it. One thing also to do is once a prime is obtained in parallel, switching the transfer valve to series boosts pressure and you can move a ton (quite literally) of water through a 2" tip.

Awesome, this is what I signed up for on EMTBravo.

Joe

[jcoppola 52]

Thanks guys! I feel refreshed, lol! I really appreciate the knowledge you all shared....even learned some things I didn't know.

In regards to salt water, besides flushing the pump, is there any other maintainence that would need to be done after drafting salt water due to its corrosive properties?

Any other tips or tricks...keep 'em coming!!

Mechanics, especially mine, will cringe at the thought of drafting salt water, but when it needs to be done, it needs to be done. The pump will survive, with liberal flushing. Since the salt water collects everywhere, a tip I was tought a long time ago was to open every single valve, drain and discharge and all intakes and flush the bejesis out ot the pump. Stamford used the salt water channel to draft at the Yale and Towne fire a few years ago, and correct me if I am wrong, but they had the foresight to use an older reserve engine to do it...good thinking.

Again, good food for thought and great thread.

Joe

[Guest]

I was taught to listen to the whine of the pump and primer. When the tone or pitches changes, you have water and open your discharge.

[mfc2257 464]

I was taught to listen to the whine of the pump and primer. When the tone or pitches changes, you have water and open your discharge.

When the pitch changes you're almost there.... Don't spin that throttle too quickly or you'll loose it like a big can of warm diet coke in the pump housing.... Let the primer really begin to dump water on the ground before you crank the throttle especially if you're lifting water a significant distance. The primer got it to the pump.... It won't drop it if you take your time from there....

There is a little finese to pulling water 20+ feet up to the rig. Open the discharge too quick, spin the throttle too quick and you may drop all that water right back to the source.

I suggest going somewhere tough to practice. Use three lengths of hard tube. Make it a good elevation change. Ride the primer and pump hard and see what it's really like. It's not as easy as it is at the training center.

[Guest]

As mentioned before, make sure all connections are TIGHT. You will here air sucking through if they are not tight, or have damaged washers. Also make sure everything on the pump is closed (drains,discharges) while priming the pump. In the last year I have learned a lot about drafting, our district has no hydrants, as opposed to my old department which utilized hydrants, and drafted once or twice a year during drills. I like the floating strainers with the flexible hard suction, no more tying off to a ladder.

Here is a photo of a whirlpool created while drafting out of a portable pond (tanker operations) with a flat bottom strainer:

You can avoid this by running a small booster line or other small handline and directing a stream at the whirlpool to break it up.

[SteveOFD 176]

A little bit off topic, in my previous Company when we sec'd the new rig, we ordered the suction sleeves with Storz couplings. For the few times I used them before I transferred they seemed to work fine. Anyone else have these couplings on their suction sleeves?

[mfc2257 464]

A little bit off topic, in my previous Company when we sec'd the new rig, we ordered the suction sleeves with Storz couplings. For the few times I used them before I transferred they seemed to work fine. Anyone else have these couplings on their suction sleeves?

My only issue with stortz fittings on hard tubes is that as the "O" ring breaks down over time, the stortz connection won't provide the pressure at the coupling that is needed to keep it air tight. With a traditional coupling, you always have the opportunity to try to tighten it. With a stortz your S.O.L if the thing isn't air tight when it snaps into place

On LDH, where the line has pressure in it, a small leak won't kill water supply, thus stortz are great. While you're drafting, a small leak can mean the difference between water at the pump or no water at all.

[firecapt32 282]

2 quick points

Seth- i still have your pump test scores.

Barry -I had a similar incident at Anacanda Wire in Hasting many years ago -pump operator was drafting out of the Hudson ---called the chief to tell him that he was pumping the river dry and needed a longer drafing hose.... needless to say the hudson has T.I.D.E. too.

It is always good to go over things

Edited March 31, 2008 by firecapt32