I will start of with a little bit about my experience on the subject, the engines that I help build put out 700-3000 hp and come in 8-20 cylinders. They are installed in LARGE vehicles such as mining trucks, dozers, loaders, ships, factories, oil shale fracturing rigs, and better than 2/3rds are stationary used in electric power generation, natural gas compression, and other factory type installations.
1. what makes a stationary engine "stationary" other than it sits in one place?
99 percent of the time they run for extended time periods, more constant loads, and constant speed.
2. what characteristics does a stationary engine have that a non stationary engine does not have?
(given similar size, power, and cylinder count)
Ours share the same basic engine but oil pans are different because of space on a vehicle, flywheel and housings are standard size on a stationary engine and matched to the application on other classes of engines. The tubochargers are sized for constant power instead of peak power. The stationary engines are mounted by their oil pans instead of mounts to the block/flywheel housing.
2. what characteristics does a stationary engine have that a non stationary engine does not have?
(given similar size, power, and cylinder count)
Oil sump and how its mounted is about it.
4. do all stationary engines have to be rigidly mounted? if so why?
Yes and No, traditionally they have been mounted to a solid base(normally concrete) but our company has made units that can be place on solid level ground. They do however need to be solidly mounted to what it is driving and there cant be and misalignment due to the mass. So if they are not bedded down they are mounted on a very stiff box section frame that has resiliant pucks underneath.
5. what are the primary reasons to rigidly mount a stationary engine?
I think most are off base here. Most stationary engines are big and heavy and drive attachments that are big and heavy. A 14 foot block that weighs 7 ton will sag 1/2 and inch in not supported evenly across its lenghth. Even when bolted solidly to a generator, the gen set needs a set of rails sufficient stiff enough to resist the mass of the package from sagging or moving out of alignment and belive me it will. Almost all stationary set ups and most large marine set ups use very heavy c channel rails or L rails for the marine setups. These have very heavy cross braces bolted up to strengthen them yet they still have to be put on a solid no moving base and realigned. Only a very heavy box section frames welded together are stiff enough to be placed on resilient pads.
6. are there examples of stationary engines that are resilient mounted?
Yes, see above
7. what make lister engines different than other stationary engines of similar size, hp, and cyl count?
(as it relates to mounting)
The vast majority of stationary engines are coupled directly to the driven load(such as a gen bolted to the flywheel bell housing) where the lister is coupled with a belt.
bob g
Show Posts