Moderators: richierich, ua900, PanAm_DC10, hOMSaR

 
floreng
Topic Author
Posts: 10
Joined: Tue Dec 22, 2009 6:21 pm

Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Sun Dec 27, 2009 6:10 am

Hi,
The subject pump is common to a variety of aircraft, including B747, B757, B767, DC-10, MD-11, A300, and A310. Does someone no if this is the EDP (engine-driven pump), or an EMDP (electric motor-driven pump)?
Thanks.
 
User avatar
fr8mech
Posts: 8075
Joined: Mon Sep 26, 2005 9:00 am

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Sun Dec 27, 2009 6:32 am

I show your second number as an EDP.
When seconds count, the police are minutes away, or may not come at all.
It’s hard to win an argument with a smart person, but it’s damn near impossible to win an argument with a stupid person. ~B. Murray
Ego Bibere Capulus, Ut Aliis Sit Vivere
 
floreng
Topic Author
Posts: 10
Joined: Tue Dec 22, 2009 6:21 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Sun Dec 27, 2009 2:07 pm

Thank you, Fr8mech. Happy Holidays!
 
474218
Posts: 4510
Joined: Mon Oct 10, 2005 12:27 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Sun Dec 27, 2009 3:46 pm

The PV3-240 Series Engine Driven Variable displacement hydraulic pump is built by Vickers Eaton.
 
User avatar
HAWK21M
Posts: 30089
Joined: Fri Jan 05, 2001 10:05 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Mon Dec 28, 2009 6:20 am

I may not win often, but I damn well never lose!!! ;)
 
floreng
Topic Author
Posts: 10
Joined: Tue Dec 22, 2009 6:21 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Mon Dec 28, 2009 3:21 pm

Thank you MEL and 474218. Happy New Year.
 
dl757md
Posts: 1483
Joined: Mon May 24, 2004 9:32 am

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Tue Dec 29, 2009 1:41 pm

Sorry I didn't see this sooner. The PV3-240-xx or MX-350880-x is a Engine Driven constant pressure/variable displacement piston type hydraulic pump. I overhauled hundreds of them back in the early ninety's. If memory serves me...the 240 stands for 2.4 cubic inches at full displacement. That means at full volume the pump would put out 2.4 cubic inches of fluid per revolution. It has 9 pistons contained in a rotary cylinder block about a central drive shaft. At the end of each piston is a shoe that rides on a surface plate that is sometimes called a wobble plate. The pump's job is to maintain system pressure at about 3000 psi. If there is no demand on the system and pressure is 3000 psi the wobble plate will be perpendicular to the axis of rotation of the drive shaft causing the pistons to remain stationary in their cylinder bores. As a demand on the system occurrs, pressure drops below 3000 psi and a regulator in the pump called a compensator will sense this and port pressure to a piston that pushes on one side of the wobble plate causing it to tilt away from perpendicular to the axis of the drive shaft causing the pistons to move up and down in their cylinder bores which in turn causes the pumping action. Full displacement at 2850 psi (remember pressure must drop for flow to happen) will give you a flow rate of 43 gallons per hour.

One to add to your list of aircraft that use this pump is the L-1011. I'm sure there are others.
The 777 uses the big brother to the pv3-240 which is the pv3-300 same basic design just bigger.

DL757Md
757 Most beautiful airliner in the sky!
 
EasternSon
Posts: 669
Joined: Fri Jun 02, 2006 10:07 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Tue Dec 29, 2009 2:10 pm

Not the greatest picture in the world, but here's what it looks like (for those who haven't seen one):

Big version: Width: 442 Height: 640 File size: 110kb
"The only people for me are the mad ones...." Jack Kerouac
 
User avatar
HAWK21M
Posts: 30089
Joined: Fri Jan 05, 2001 10:05 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Wed Dec 30, 2009 6:43 am



Quoting DL757Md (Reply 6):
I overhauled hundreds of them back in the early ninety's

How long was an overhaul on average timewise?
regds
MEL.
I may not win often, but I damn well never lose!!! ;)
 
EasternSon
Posts: 669
Joined: Fri Jun 02, 2006 10:07 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Wed Dec 30, 2009 2:27 pm



Quoting HAWK21M (Reply 8):
How long was an overhaul on average timewise?

Depends on the shop.  Smile

Some shops do what they call an "overhaul", but rarely check the piston and cylinder blocks to see if the dimensions are correct. Likewise, they don't replace bearings if they still spin freely. Accoding to the CMM, you can't certify the unit as overhauled unless all the dimensional checks are completed and passed, and the full list of required parts (as defined per the CMM) have been replaced. They call it an "overhaul", complete it in 5 days, and charge $2K.

The reputable shops will complete it in about 15 days, and the true cost of the overhaul is closer to $4,500 - $5K.
"The only people for me are the mad ones...." Jack Kerouac
 
dl757md
Posts: 1483
Joined: Mon May 24, 2004 9:32 am

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Wed Dec 30, 2009 6:45 pm



Quoting HAWK21M (Reply 8):
How long was an overhaul on average timewise?



Quoting EasternSon (Reply 9):
Depends on the shop.

Some shops do what they call an "overhaul", but rarely check the piston and cylinder blocks to see if the dimensions are correct. Likewise, they don't replace bearings if they still spin freely. Accoding to the CMM, you can't certify the unit as overhauled unless all the dimensional checks are completed and passed, and the full list of required parts (as defined per the CMM) have been replaced. They call it an "overhaul", complete it in 5 days, and charge $2K.

The reputable shops will complete it in about 15 days, and the true cost of the overhaul is closer to $4,500 - $5K.

We did on average 1 pump in an 8 hour shift per technician. That included teardown, cleaning, inspection-measuring all items per the CMM, ordering replacement parts from stock, lapping rotating parts to >.000016" flatness, setting internal clearances, assembly, test, and returning to service.

It got very boring though and once I did 3 in one day just to challenge myself. The old guys in the shop got pissed about that though so I had to turn elsewhere for a challenge. We had all the parts and machine shop and engineering support we needed and our shop had been doing that particular pump for over 20 years so we were very efficient at it. Our Vickers Tech Rep told us we were about 5X faster than their in-house repair and our on-wing time averaged close to 3 times longer than the pumps they repaired. They charged $4500 for labor parts not included back in the 90's.

DL757Md
757 Most beautiful airliner in the sky!
 
User avatar
HAWK21M
Posts: 30089
Joined: Fri Jan 05, 2001 10:05 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Thu Dec 31, 2009 5:43 am



Quoting EasternSon (Reply 9):
Accoding to the CMM, you can't certify the unit as overhauled unless all the dimensional checks are completed and passed

So What do those certifying agencies call their work which avoids the dimensional check.

Quoting DL757Md (Reply 10):

It got very boring though and once I did 3 in one day just to challenge myself.

Yeah.Thats what worries me about any shop work.It can get routine over time.I try switching between Major & line Mx to avoid the same problem,normally keep away from shops.  Smile

regds
MEL.
I may not win often, but I damn well never lose!!! ;)
 
EasternSon
Posts: 669
Joined: Fri Jun 02, 2006 10:07 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Thu Dec 31, 2009 9:02 pm



Quoting DL757Md (Reply 10):
We did on average 1 pump in an 8 hour shift per technician.

Yes, that sounds about right. However, it has to come through the back door and be placed in the work cycle, get a pre-test if possible, be torn down and inspected, parts pulled from stock, and any parts not in stock need to be requisitioned. The unit needs to be quoted to the customer, and approved. Once approved, those requisitions have to be bought on, shipped, received, inspected and allocated. Once allocated, the tech has to re-assemble and final test. Then the unit can be invoiced and shipped.

The bench time is one thing, but add in the rest of the steps in the work cycle, and it's much longer. Twelve to fifteen days is standard for an OH across the 3rd party maintenance world.

Quoting HAWK21M (Reply 11):
So What do those certifying agencies call their work which avoids the dimensional check.

They call it an overhaul - even though they shouldn't. We call this type of work an "aerosol overhaul" - mostly because they just make the part look pretty without doing much work. It comes from the practive of replacing as little as you can to reduce your costs, and just spray painting the unit so it looks new - Aerosol Overhaul.
"The only people for me are the mad ones...." Jack Kerouac
 
User avatar
HAWK21M
Posts: 30089
Joined: Fri Jan 05, 2001 10:05 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Thu Dec 31, 2009 9:35 pm



Quoting EasternSon (Reply 12):

They call it an overhaul - even though they shouldn't. We call this type of work an "aerosol overhaul" - mostly because they just make the part look pretty without doing much work.

Isn't that a Violation of Regulations in place.
If the COM states a process for Overhaul.It should be followed accordingly.
The customer airline could raise a complaint if it could be proven.

regds
MEL.
I may not win often, but I damn well never lose!!! ;)
 
EasternSon
Posts: 669
Joined: Fri Jun 02, 2006 10:07 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Mon Jan 04, 2010 5:41 pm



Quoting HAWK21M (Reply 13):
Isn't that a Violation of Regulations in place.
If the COM states a process for Overhaul.It should be followed accordingly.
The customer airline could raise a complaint if it could be proven.

Unfortunately, Mel, it happens.

To give you an example, one of my airline customers bought an "Overhauled" pump (similar to the 350880, but not identical) from another shop, and sent it to us to have their engineering order incorporated. We did a pre-test of the pump, as we normally do, and found that the flow and pressure were low. We opened it up, and found that nearly all the cylinder bores were out of scope, and the pistons incorrectly sized. Obviously, this will effect the efficiency of the pump. The 8130-3 (from a "reputable" company) stated OH, even though the critical areas fell outside the acceptable measurements.

I don't know for sure, but I believe the other shop had been taken off the airline's approved vendor list for that particular pump.

There are some shady practices out there. Unfortunately, it makes it hard for the good shops to compete. As I said, if I know my out of pocket costs to complete the overhaul are "X" dollars, not including labor, and another shop is charging half of "X" for the OH, it makes it difficult for me to sell my services.

The good thing is that many airline repair buyers understand that you get what you pay for.
"The only people for me are the mad ones...." Jack Kerouac
 
User avatar
HAWK21M
Posts: 30089
Joined: Fri Jan 05, 2001 10:05 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Wed Jan 06, 2010 7:48 am



Quoting EasternSon (Reply 14):

There are some shady practices out there

The ones that lower charges because the work involved is less than accurate.
Sad......
I guess the Pump having a problem in less than normal time is a clue,but it should be sent to another shop for a strip report to know the cause.

regds
MEL.
I may not win often, but I damn well never lose!!! ;)
 
EasternSon
Posts: 669
Joined: Fri Jun 02, 2006 10:07 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Wed Jan 06, 2010 2:27 pm



Quoting HAWK21M (Reply 15):
I guess the Pump having a problem in less than normal time is a clue,but it should be sent to another shop for a strip report to know the cause.

Most of the time the repair buyers at the airline are sensitive to the fact that a cheap overhaul won't last as long on wing as a quality overhaul. However, unfortunately, with the state of the industry these days, everyone is looking to lower costs, are under pressure from bosses, and are more inclined to give an unknown shop a chance just based on the promise of a lower repair price. They eventually realize it costs them more money in the long run, though.
"The only people for me are the mad ones...." Jack Kerouac
 
User avatar
HAWK21M
Posts: 30089
Joined: Fri Jan 05, 2001 10:05 pm

RE: Hydraulic Pump P/n PV3-240-2F/G/H, 350880-6/7

Wed Jan 06, 2010 5:51 pm



Quoting EasternSon (Reply 16):
They eventually realize it costs them more money in the long run, though.

On realizaton ,the airline would choose a different Overhaul facility,but what about a complaint against the irresponsible facility.
regds
MEL.
I may not win often, but I damn well never lose!!! ;)

Who is online

Users browsing this forum: ARNPEK, lhwj, n757kw and 29 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos