Haskel vs HI

**vidodivr** · 23rd July 2007, 22:40

Okay,
I may have missed this thread somewhere, so gimme the link if I did.

Is the Haskel worth the other 500 or more US $ or is the HI just fine and dandy? I'm sure they both get the job done just fine, but I'd like to hear some comments.

diverreb · 25th July 2007, 14:10

I'm using a Haskel Mini and after changing the flow control exhaust valve, it screams. The original one on the unit was not adjusted correctly and all I was getting was a maximum of 14 cycles per minute.

Not being very familiar with Boosters I didn't know how they should really work.

The way the valve was set it kept blowing off the small OPV valve if I ran it full bore. I assumed it was a bad OPV, but they sent me both and it turned out the flow control exhaust valve was the problem.

While it worked OK, it took a while to boost the gas. Coltri Americas, the Haskel Distributor here in the US was great....They got me the replacement part in a two days.

Now the unit cycles at 60 or more cycles a minute and pumps up to the specs listed on their unit, although I slow it down when pumping O2.

As far as which pump to buy.... Haskel has a great name in the booster business. Will you get specific information as to why it costs $400 - $500 more than the others... I doubt it.

I just figured it was quality of build and the Haskel name that play a part in the decision. The duty cycle should be better on the Haskel, as far as a longer time to change parts out. It's built to run hard.

Is the HI a single action pump? Haskel has a double action pump. It will run on a drive gas as low as 80 - 90 psi, even though they state 100 psi as the minimum. It's got a 25:1 ratio, you can check that against the HI.

Most people seem to like which ever pump they buy.... For me Haskel is the name in Boosters. In a year or two I'll let you know if I was correct in my assumptions.

Richie

**vidodivr** · 25th July 2007, 20:47

Thanks for your comments

tomhanaway · 26th July 2007, 00:34

Richie,
I have a Haskel mini and am not quite sure which flow control valve you're talking about. One you screwed in to attach the hose to fill a tank or a flow control valve that allows the exhaust of the drive gas to leave the booster during a cycle? If it's an exhaust valve that relates to the drive gas, what was the replacement?
Thanks,
Tom H.

Quote: (Originally Posted by diverreb)

I'm using a Haskel Mini and after changing the flow control exhaust valve, it screams. The original one on the unit was not adjusted correctly and all I was getting was a maximum of 14 cycles per minute.

Not being very familiar with Boosters I didn't know how they should really work.

The way the valve was set it kept blowing off the small OPV valve if I ran it full bore. I assumed it was a bad OPV, but they sent me both and it turned out the flow control exhaust valve was the problem.

While it worked OK, it took a while to boost the gas. Coltri Americas, the Haskel Distributor here in the US was great....They got me the replacement part in a two days.

Now the unit cycles at 60 or more cycles a minute and pumps up to the specs listed on their unit, although I slow it down when pumping O2.

As far as which pump to buy.... Haskel has a great name in the booster business. Will you get specific information as to why it costs $400 - $500 more than the others... I doubt it.

I just figured it was quality of build and the Haskel name that play a part in the decision. The duty cycle should be better on the Haskel, as far as a longer time to change parts out. It's built to run hard.

Is the HI a single action pump? Haskel has a double action pump. It will run on a drive gas as low as 80 - 90 psi, even though they state 100 psi as the minimum. It's got a 25:1 ratio, you can check that against the HI.

Most people seem to like which ever pump they buy.... For me Haskel is the name in Boosters. In a year or two I'll let you know if I was correct in my assumptions.

Richie

diverreb · 26th July 2007, 03:20

There are two valves on the unit. On the top cylinder there is a small OPV valve rated at 155 psi. It's not adjustable. The Flow Control Exhaust Valve is the one on the smaller lower cylinder... It has the round holes on the side and a small nut over an adjustable screw on the top of it.

The original one I had wasn't adjusted properly and restricted the cycling on the unit to about 14 cycles a minute before it would set off the small OPV. When I got the replacement I could see that more of the screw was showing. Had I known that was all it needed I could have loosened the nut and backed the screw out a bit myself.

At any rate the booster now can cycle at over sixty cycles per second, using high pressure air, to drive it. But at full bore it really sucks down the drive gas. I use the Quarter Turn Ball Valve I installed to back it down, especially when pumping O2. If I'm doing Helium I let run full bore.

Here a two shots, one showing the height of the screw on the newer Flow Control Exhaust Valve, and the other is of the whole unit.

Richie

Hanssing · 26th July 2007, 10:21

Quote: (Originally Posted by diverreb)

There are two valves on the unit. On the top cylinder there is a small OPV valve rated at 155 psi. It's not adjustable. The Flow Control Exhaust Valve is the one on the smaller lower cylinder... It has the round holes on the side and a small nut over an adjustable screw on the top of it.

Hi Richie,

Very interesting,
I've bought a HII 5G-SS-30-OT, which is quite big for my purpose....
But I've only yet done trst-runs with it.
Both the Haskel and the HII seems to only use drivegas on the compression-stroke of the cycle. Therefor its the boostgas supply-pressure the drive the other half of the cycle (In HII-speak this is modification type T).
My observations were that when boosting from high pressures the return-stroke was violently fast, so much that the booster jumped along the floor....

Both before I recieved it, and after I was in contact with:
Les E. Turner, Director, Sales & Marketing, HII.
He actually didnt know any details and was not very willing to reply to technical inquiries, but I contacted them repeatedly since I was worried that the booster would fail.

This is a part of my email and his reply (I'm in blue):
-----------------------------------------------------
When boosting Oxygen with a high inlet pressure (200bar/3000psi or more) the compression-cycle can be controlled by reducing the flow of the drivegas. However when the cycle is finished, and the piston reverses, the drive-gas is very quickly released through the booster-cooler and out through the muffler. Then the piston rams hard into bottom position, and cycle repeats.

Question: Can the booster handle this through is projected lifetime?
Returnstroke is way above 60 cycles/min.

The return stroke is less harmful using Modification “T”. In order to prolong the life expectancy of the seals, yuou must maintain a cycle rate less than 50 cpm for continuous operation.

The only way I can reduce speed of the return-stroke is currently to reduce input-flow and pressure, which significantly reduces effeciency of booster, and introduces added heat-generation during boosting.

Or normal experience from pneumatic cylinders (festo, SMC etc.) tell us, that of you want to reduce the stroke-speed, you limit the flow of the releasing piston-side.
But how can I achive the same effect without compromising the Booster-stage cooling? You may try to restrict the exhaust air.
And how can this be implemented so low input pressures are not impeeded to much?
Does HII have a solution for this?

My guess is that optimally the flow released from the compression-side of the cylinder should be limited before entering the cooling-shroud of the boostercylinder, this will cause the drive.gas entering the cooling stages to be coldest, due to the pressure-drop.
This however is not a simple modification.

If flow is limited on the muffle-output, there's more dead volume, which will cause the piston to jerk back and the start, but then move slowly after?
Will this supply adequate cooling? Regardless what you do to the booster, if you maintain a cycle rate higher than 50 cpm you will generate heat.
Is the muffler-fitting rated for 147PSI?
---------------------------------------------------------
So I have to get some sort of adjustable limiter for my booster, wich is allready included on the Haskel......
If I were to make a purchase again, I would go with a haskel, based soly on the fact that they seem to be knowing that such a flow reducer is needed!

I've included a picture of the cooling-shroud and the muffler (missing a flow-reducer).

Regards
Nicolai

diverreb · 26th July 2007, 13:17

Quote: (Originally Posted by Hanssing)

Hi Richie,

Very interesting,
I've bought a HII 5G-SS-30-OT, which is quite big for my purpose....
But I've only yet done trst-runs with it.

Both the Haskel and the HII seems to only use drivegas on the compression-stroke of the cycle. Therefor its the boostgas supply-pressure the drive the other half of the cycle (In HII-speak this is modification type T).

Regards
Nicolai

The Haskel uses the drive gas for both sides of the cycle. It's a double action booster. Some of the others are single action and use the boost gas for half the cycle. That may be another plus for the unit.

Richie

Richie

robinfante · 26th July 2007, 15:39

I've got the HI. Its been nothing but misery. It went back to the factory after about an hour of use, they didn't get it back to me for 8 months (and dozens of "shipping next week" promises.) Guess what? It still doesn't work.

You may be able to find mine on the bottom of the ocean soon.

**kybrt** · 27th July 2007, 03:03

Rob,

get the numbers for me please........

quote" you may find mine on the bottom...."

Hanssing · 27th July 2007, 08:12

Quote: (Originally Posted by diverreb)

The Haskel uses the drive gas for both sides of the cycle. It's a double action booster. Some of the others are single action and use the boost gas for half the cycle. That may be another plus for the unit.
Richie

Well depends on your drivegassupply (mine is scuba-bottles) - since it uses a lot more gas. Worst case is double the amount when boosting low pressure.
My booster however becomes slow on the returnstroke when input-pressure is low.

Compression-stroke for fixed input-flow:
Low output-pressue -> Fastest (least amount of drivegas per stroke)
High output-pressure -> slowest (higest amount of drivegas per stroke)

Return-stroke for fixed drivegas release-flow (limiter):
Low input-pressue -> Slowest
High input-pressure -> Fastest

This means that the booster will automatically scale down the speed when input-pressure is low and output pressure is high - and this is a good thing, because this is where there's most heating due to adiabatic compression. Most importantly is of course the compression-stroke, but the total cyclespeed will allow heat created during the compression to better get distributed through the metal.

Nicolai

23rd July 2007, 22:40	#1 (permalink)
vidodivr swims in fishes toilets Current Rebreather/s: Classic Kiss Other Rebreather/s: Join Date: Nov 2005 Location: Florida/Michigan Posts: 499	Haskel vs HI Okay, I may have missed this thread somewhere, so gimme the link if I did. Is the Haskel worth the other 500 or more US $ or is the HI just fine and dandy? I'm sure they both get the job done just fine, but I'd like to hear some comments. __________________ Have a good one, Rob LaLonde Rec and Tek Media, Inc. Full Service Film and Video Production CK #087, Narked@90 stand, URM
(Online)

25th July 2007, 14:10	#2 (permalink)
diverreb DE/MD/NJ Wreck Diver Current Rebreather/s: Optima Other Rebreather/s: Join Date: Mar 2007 Location: Dover, DE Posts: 595	Re: Haskel vs HI I'm using a Haskel Mini and after changing the flow control exhaust valve, it screams. The original one on the unit was not adjusted correctly and all I was getting was a maximum of 14 cycles per minute. Not being very familiar with Boosters I didn't know how they should really work. The way the valve was set it kept blowing off the small OPV valve if I ran it full bore. I assumed it was a bad OPV, but they sent me both and it turned out the flow control exhaust valve was the problem. While it worked OK, it took a while to boost the gas. Coltri Americas, the Haskel Distributor here in the US was great....They got me the replacement part in a two days. Now the unit cycles at 60 or more cycles a minute and pumps up to the specs listed on their unit, although I slow it down when pumping O2. As far as which pump to buy.... Haskel has a great name in the booster business. Will you get specific information as to why it costs $400 - $500 more than the others... I doubt it. I just figured it was quality of build and the Haskel name that play a part in the decision. The duty cycle should be better on the Haskel, as far as a longer time to change parts out. It's built to run hard. Is the HI a single action pump? Haskel has a double action pump. It will run on a drive gas as low as 80 - 90 psi, even though they state 100 psi as the minimum. It's got a 25:1 ratio, you can check that against the HI. Most people seem to like which ever pump they buy.... For me Haskel is the name in Boosters. In a year or two I'll let you know if I was correct in my assumptions. Richie
(Online)

25th July 2007, 20:47	#3 (permalink)
vidodivr swims in fishes toilets Current Rebreather/s: Classic Kiss Other Rebreather/s: Join Date: Nov 2005 Location: Florida/Michigan Posts: 499	Re: Haskel vs HI Thanks for your comments __________________ Have a good one, Rob LaLonde Rec and Tek Media, Inc. Full Service Film and Video Production CK #087, Narked@90 stand, URM
(Online)

26th July 2007, 00:34	#4 (permalink)
tomhanaway New Member Current Rebreather/s: Prism Topaz Other Rebreather/s: Prism Topaz Join Date: May 2005 Location: Boynton Beach, FL Posts: 52	Re: Haskel vs HI Richie, I have a Haskel mini and am not quite sure which flow control valve you're talking about. One you screwed in to attach the hose to fill a tank or a flow control valve that allows the exhaust of the drive gas to leave the booster during a cycle? If it's an exhaust valve that relates to the drive gas, what was the replacement? Thanks, Tom H. Quote: (Originally Posted by diverreb) I'm using a Haskel Mini and after changing the flow control exhaust valve, it screams. The original one on the unit was not adjusted correctly and all I was getting was a maximum of 14 cycles per minute. Not being very familiar with Boosters I didn't know how they should really work. The way the valve was set it kept blowing off the small OPV valve if I ran it full bore. I assumed it was a bad OPV, but they sent me both and it turned out the flow control exhaust valve was the problem. While it worked OK, it took a while to boost the gas. Coltri Americas, the Haskel Distributor here in the US was great....They got me the replacement part in a two days. Now the unit cycles at 60 or more cycles a minute and pumps up to the specs listed on their unit, although I slow it down when pumping O2. As far as which pump to buy.... Haskel has a great name in the booster business. Will you get specific information as to why it costs $400 - $500 more than the others... I doubt it. I just figured it was quality of build and the Haskel name that play a part in the decision. The duty cycle should be better on the Haskel, as far as a longer time to change parts out. It's built to run hard. Is the HI a single action pump? Haskel has a double action pump. It will run on a drive gas as low as 80 - 90 psi, even though they state 100 psi as the minimum. It's got a 25:1 ratio, you can check that against the HI. Most people seem to like which ever pump they buy.... For me Haskel is the name in Boosters. In a year or two I'll let you know if I was correct in my assumptions. Richie
(Offline)

26th July 2007, 13:17	#7 (permalink)
diverreb DE/MD/NJ Wreck Diver Current Rebreather/s: Optima Other Rebreather/s: Join Date: Mar 2007 Location: Dover, DE Posts: 595	Re: Haskel vs HI Quote: (Originally Posted by Hanssing) Hi Richie, Very interesting, I've bought a HII 5G-SS-30-OT, which is quite big for my purpose.... But I've only yet done trst-runs with it. Both the Haskel and the HII seems to only use drivegas on the compression-stroke of the cycle. Therefor its the boostgas supply-pressure the drive the other half of the cycle (In HII-speak this is modification type T). Regards Nicolai The Haskel uses the drive gas for both sides of the cycle. It's a double action booster. Some of the others are single action and use the boost gas for half the cycle. That may be another plus for the unit. Richie Richie
(Online)

26th July 2007, 15:39	#8 (permalink)
robinfante I have a smoking gun Current Rebreather/s: Megalodon Prism Topaz MK 15.X Other Rebreather/s: Sport Kiss Join Date: Nov 2005 Location: mountain lakes nj Posts: 148	Re: Haskel vs HI I've got the HI. Its been nothing but misery. It went back to the factory after about an hour of use, they didn't get it back to me for 8 months (and dozens of "shipping next week" promises.) Guess what? It still doesn't work. You may be able to find mine on the bottom of the ocean soon. __________________ Homer to Bart: “When a woman says nothing’s wrong, everything is wrong. And when a woman says everything’s wrong, EVERYTHING is wrong. And when a woman says something’s not funny, you better not laugh your ass off!” Check out www.robinfante.blogspot.com for trip reports and pics.
(Offline)

27th July 2007, 03:03	#9 (permalink)
kybrt too legit to quit Current Rebreather/s: rEvo Other Rebreather/s: rEvo Join Date: Jan 2007 Location: Neuw Yawk Posts: 338	Re: Haskel vs HI Rob, get the numbers for me please........ quote" you may find mine on the bottom...." __________________ Marv Fidelis Ad Mortem www.diveboatkaren.com
(Offline)

27th July 2007, 08:12	#10 (permalink)
Hanssing flap-flop ..... flap-flop Current Rebreather/s: rEvo Other Rebreather/s: rEvo Join Date: Nov 2005 Location: Denmark Posts: 405	Re: Haskel vs HI Quote: (Originally Posted by diverreb) The Haskel uses the drive gas for both sides of the cycle. It's a double action booster. Some of the others are single action and use the boost gas for half the cycle. That may be another plus for the unit. Richie Well depends on your drivegassupply (mine is scuba-bottles) - since it uses a lot more gas. Worst case is double the amount when boosting low pressure. My booster however becomes slow on the returnstroke when input-pressure is low. Compression-stroke for fixed input-flow: Low output-pressue -> Fastest (least amount of drivegas per stroke) High output-pressure -> slowest (higest amount of drivegas per stroke) Return-stroke for fixed drivegas release-flow (limiter): Low input-pressue -> Slowest High input-pressure -> Fastest This means that the booster will automatically scale down the speed when input-pressure is low and output pressure is high - and this is a good thing, because this is where there's most heating due to adiabatic compression. Most importantly is of course the compression-stroke, but the total cyclespeed will allow heat created during the compression to better get distributed through the metal. Nicolai __________________ Woohooo - I can change my rEvo! Its going to be bitchin' tricked out piece of gear
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