Pumping Question

[darook]

Just looking through some notes from my pump operators course, I am a little confused on pumping into a pump relay valve. If im pumping into a relay valve to boost pressure for another apparatus, once I have layed dry lines from relay valve into my truck and dry lines from my truck back into relay valve. My notes here say the next step is to open pump intake and let water into pump and open dishcarge on truck to let water flow back to relay valve, THEN put pump in gear and throttle up, Im thinking that its hard on pump to have water flowiing through it when putting it into gear? Im thinking I would bring water to intake gate on truck, put into pump gear, then open discharge and let water flow to relay valve, then throttle up?

[Spencer534]

Shouldnt be any harder or less harder to engage pump with water or without. Unless you are draining your pump after each time, it already has water in it. As far as it being under hydrant pressure, your pump is used to much higher pressures I would assume. Not sure it makes a difference either way with the relay valve.

[darook]

yeah the pump would have water in it. So engaging pump with hydrant pressure already flowing through it,isnt hard on pump? wont make it take off will it?

[MG3610]

I would always engage the pump before I left the cab, then open my TTP line and crack the tank fill to circulate water while I make my hookups. When I have connected to the valve, I would change the valve over to "boost" mode and let the water fill up the line to my pump (it will not stop water from flowing to the rig already operating). Next, I will open my intake, then the discharge back to the valve and begin to throttle up. I close my TTP valve after I'm all set and switched over.

Waiting to engage the pump doesnt make much sense to me?

[KB1OEV]

I think we need to differentiate between engaging the pump with water in it, and engaging the pump with water flowing through it (pump spinning).

The former should be no problem at all. I would not engage the pump with water flowing though it. That could be bad, kind of like engaging the pump while the truck is still in gear.

[LFD2203]

Waiting to engage the pump doesnt make much sense to me?

What him said.

[darook]

Yes thats what im trying to figure out, if you put the truck in pump gear with water flowing through it already, is it hard on the pump?

[MG3610]

You will see a pressure increase, probably around 25 PSI.....i don;t think it's necessarily that hard on the pump as much as I wonder why you would do it that way?

[RFDACM02]

It could be they anticipate you may not have a valve on the intake side of the pump? You don't want to have the pump spinning when you open the main steamer to the air, right? Most of us likely now run with a properly sized gated auxiliary suction, an external gated relief valve or have an internal gate on the main suction.

[CKirk922]

It could be they anticipate you may not have a valve on the intake side of the pump? You don't want to have the pump spinning when you open the main steamer to the air, right?

This is the stated reason for this action in the classes I've been in. Often the instructor will mention opening an extra discharge to bleed the air as the line fills. When the air is bled, close your bleeder( extra discharge) and move on with the operation including putting the pump in gear.

I'm not sayin it's right or wrong, just saying that is the explaination I've heard repeatedly.

[kuh shise]

Midship pump with transfer case... Place transfer case in gear, establish water flow, engage transmission. This avoids forcing the sliding collar of the transfer case to move from road position (not turning) to powering the pump with the pump shaft turning.
A PTO pump with a hot-shift has synchronizing capability so it wont hurt to put it into gear with the output shaft turning. Some relay valves have a clapper between the input and output, so it will be possible to make all the connections, but leave the discharge valve closed until the pump has been engaged and air removed from the pump. Then opening the discharge and throttling up will automatically close the clapper and pressureize the relay.

[LFD2203]

I am still confused with this discussion. Why do anything that requires the operator to get back in the cab of the apparatus after making these, or any other hose connections? I just can't see why the pump wouldn't be engaged before the apparatus driver exits the cab to become the pump operator.

I was taught, and have taught, to engage the pump, engage the transmission, then open the tank discharge valve and crack open the tank fill valve. Then go make connections, assure preconnects have cleared the bed, or whatever else you need to do before opening the appropriate discharge and advancing the throttle to send water where you want it to go.

Opening the tank valves prevents any damage or overheating while the pump is engaged but not flowing water. If you have any air in the pump, it may very well "burp" the air out. If the pump has been drained, fully open the tank fill valve to allow the air to be pushed out of the pump by the tank water gravity feeding into the pump.

[JayDudley]

I always ran with a wet pump. There are some who do not. That is the only way i can see damage to the pump is if you run a dry pump and engage the pump from the cab. Granted its only for a few seconds but I never engaged the pump dry. Stop...set brakes.....engaged pump and the short time you are running the pump in idle and nowhere for the water to go I would open the tank to pump valve to circulate the water to keep it cool.

[kuh shise]

Running a dry pump for a "few seconds" or even a minute is not a problem, however the few seconds it takes to re-enter the cab after making the connections is a small inconvenience with a big safety factor. Many times as a pump operator, I am the only person making the connections. There are many reasons that the rapid, successful connection of supply and discharges can be interrupted. Turning a dry packing or ceramic seal for an excessive period of time can and does create significant repair costs. Packing and shaft wear is a long term degredation of the seal. On the other hand a carbon / ceramic seal can fail catrostrophically when a hot seal is suddenly chilled by the introduction of cold water to the pump.

[LFD2203]

Sorry, I never intended to imply that the steps I suggested would be OK on a dry pump. From the scenario in OP, I guess that could be construed that the pump is dry, and if it that is the scenario, then I would have to assume that the engine implied in the OP's scenario has no water tank. If pump is completely dry, and there is no water in tank to keep seal from frying, then I'm good with not putting pump in gear before exiting cab.

[RFDACM02]

Again, maybe everyone has gated intakes on all sides, but think about what would happen if you engage the pump, exit the cab then open the main steamer port into the pump to make your connection, without it being gated. When you're drafting do you engage the pump before making you suction connections?

[FyredUp]

Again, maybe everyone has gated intakes on all sides, but think about what would happen if you engage the pump, exit the cab then open the main steamer port into the pump to make your connection, without it being gated. When you're drafting do you engage the pump before making you suction connections?

Yes, I engage the pump before making the suction connections because I will initially operate off the tank. Our engine has 1000 gallons on baord and maybe they can effect knockdown or make a rescue with that water while I am establishing a water supply.

[RFD21C]

Yes, I engage the pump before making the suction connections because I will initially operate off the tank. Our engine has 1000 gallons on baord and maybe they can effect knockdown or make a rescue with that water while I am establishing a water supply.

Whilie i agree with what you are saying. I am willing to bet you have a butterfly valve or PIV on the steamer connection. If not please tell me how you do it. i would think taking the steamer cap of the steamer connection would result in all the water flowing out of the pump. Unless you gated you tank to pump to the point that your intake from the tank was the same as you discharge GPM. Similar to duel pumping. Just shooting from the hip couldnt tell you if it works or not.

[CaptOldTimer]

Whilie i agree with what you are saying. I am willing to bet you have a butterfly valve or PIV on the steamer connection. If not please tell me how you do it. i would think taking the steamer cap of the steamer connection would result in all the water flowing out of the pump. Unless you gated you tank to pump to the point that your intake from the tank was the same as you discharge GPM. Similar to duel pumping. Just shooting from the hip couldnt tell you if it works or not.

Hey, didn't the instructors at the drill school ever show you newer members, that you can take the other steamer cap off, while having water coming in the other side and make a connection with another hard sleeve?

It can be done.

[RFD21C]

Hey, didn't the instructors at the drill school ever show you newer members, that you can take the other steamer cap off, while having water coming in the other side and make a connection with another hard sleeve?

It can be done.

Yes Cap, duel pumping. I was unsure about the ablity to pull a draft with that way. And am unsure about the residual flow from the tank to pump doesnt that come out of the intake.