As mentioned in an earlier article, one of the three N.F.P.A. cylinder mounting classes is fixed non-centerline mounts. These mounts include side lug (MS2), end lug (MS7), side flush (MS4), and foot bracket (MS1). In applications where a fixed non-centerline mount is required, Sheffer strongly recommends employing a thrust key plate or dowel pinning the cylinder depending upon the specific mount. This is done to minimize shear loads on the mounting bolts as well as providing a means of cylinder alignment.

In 1962, E.F. Houghton Co. published A Handbook On Hydraulic and Pneumatic Packings for the fluid power industry. In the opening chapter there is an illustration of a “typical animal hide” which depicted the best parts of the hide that could be fabricated into leather “U” cups, “V” rings, and gaskets to seal fluid power cylinders.

Cylinder Mounting & Column Loading

“I need 100,000 pounds of force on a 120” stroke with a 2” diameter piston rod and clevis mount.” A click and then there is no one on the other end of the phone. 

Cylinders convert a fluid pressure into a mechanical force.  The input fluid pressure acts on the surface area of the cylinders piston displacing it to create a linear movement of the piston rod.

Well, if that isn't a loaded question. Over the years more people than you would expect have proposed this puzzle and while there may be no single answer to this complex query, there are many variables to consider in attempting to answer it -- so let's start there.

In our experience, the call for more than one mounting feature on a cylinder is by no means a rare event.

We won’t say that all mounts can be combined; as clearly there are some features which would just interfere with each other. For instance, a Front Head (FHF) and a Side Lug (SL) cannot coexist on the same end of a cylinder. What is possible, however, is to have an FHF (Head) mount combined with a Side Lug at the Cap; if that serves a useful design purpose for you.

Boosters or intensifiers are used to create a high pressure output from a low pressure input. Much like how an electrical transformer works by trading current for voltage, a hydraulic booster transforms a larger volume of low pressure fluid into a smaller volume at a higher pressure.

Those engineers in the know; will be all too familiar with the possibility of bacterial growth within the relatively cozy environment of a hydraulic system. So these thoughts are probably only going to be of interest to the tiny minority of system designers and maintenance engineers who are dealing with a certain type of installation.

When charged with the notorious "beating your head against a wall", and at the very least unpleasant, task of choosing a cylinder supplier -- one can quickly become disenchanted with all of the industry hype and mumbo jumbo.

From the mammoth sized companies, in which you can get lost and slip through the cracks, to the miniature sized companies that don't offer competitive quality or the same kinds of guarantees as the "big guys" -- the options seem pretty limited.

Most cylinders are fixed at one point along their length. Although there is guidance and best practices associated with all of the mounting types --our thoughts go back to the times we have seen side lug cylinders used incorrectly – in one case; to the extent that the tube to cap joint was ruined.