View Full Version : Grasso Single Screw Compressor

20-03-2009, 02:27 PM
Hi Guys

I found this picture on my PC and thought I would share it with you all.

This is a bit of refrigeration history I guess.

Grasso used to make a single screw compressor mainly for marine applications before J & E Hall refined the technology further.

The Compressor would be returned to the Grasso factory in Hertogenbosch for overhaul after exceeding the recommended run hours on a service exchange basis.
Still do toady as far as I know?

Hope you enjoy.


22-03-2009, 06:30 PM
Hi Sturt,
The one in your picture looks like the one RM-Support has for sale. Have a look at my avatar and you will see a MS 1030 used on the high side of the plant that I had stripped out for gland service. Built in 1974 and still running with some MS1034 units as low side boosters.
all the best Arthur

23-03-2009, 08:48 AM
Hi Arthur

Great stuff thanks for replying.

I dont have any information on the construction of these. Do they have a single star wheel?

It looks as if the whole compressor body needs to be split for major works?

Thanks again.


23-03-2009, 01:51 PM
hi Sturt,
They have two star wheels the same as the Halls unit, Grasso stopped overhaul/servicing them some time in 1986-87. We have split two old dead units after the rear main bearing on the rotor shaft had worn letting the rotor move backwards. But you could not get the bearing from SKF as Grasso owned it's rights. Can still get some parts for them from Grasso. A lot of the Grenco engineers have not seen one or worked on them.

24-03-2009, 09:46 PM
Hi all MonoScrew Enthousiasts!

The base idea is very old, around 1500 Leonardo da Vinci used already this principle (globoide worm mechanisme). The Frenchman Zimmern was the inventor of an air compresser according this principle and Grasso got the rights (in 1971) after 4 years development they succeeded to transform it into a refrigeration compressor. It was patented, also the name MonoScrew. Main (driven rotor) was made of aluminium and the 2 side wheels were cast iron. Because of it's symmetry it was almost vibration free! The precious production of the wheels became a problem with the machinery in those days. The best was to start and than never stop, than they could run ages ! (breweries etc)

If interested I can scan the origanal introduction brochure.

I'm refr. eng at GEA Grenco (a daughter company of Grasso) and I worked with the MonoScrew

Nowadays Daikin makes them too (very small onesin AC units) also Filter and Hall.


26-03-2009, 02:49 PM
Hi Ernst

Thanks for the information.

I've heard the Zimmern name before in relation to these compressor types.

I would be interested to see the original brochure and then I think we have great history thread for sure.


23-02-2010, 07:11 PM
we have a client that has 2 of these still running, (had3) over 20 years old and have never had a spanner near them, noisey old thing but serviced there perpuse i guess

24-02-2010, 09:09 AM
Hi all, Had a sad day at the start of this year when I shut down and pumped out for the last time all of the Ammonia from our old system powered by the mono screws. But on a better note we are now running on two new SP two stage duo packs at around 1.25 maga watt,s.