Static Equipment

Credits: Ganesh Polubothu; Procurement, Reliance Industries Limited

Here I am going to describe what I learnt related to external and internal attachments of static equipment so that it can be shipped and handled properly and without much risks. The strategy here should be to take unit prices on per kg basis for everything also (don't forget to negotiate) at the initial phases and use them according to your needs. Also do understand that per kg rates has got to be less than per kg rates for manufactured equipment !!

The explanatory images will tell you more about the equipment; also about my poor drawing skills and low budget of this website :)

Truss: Lets suppose you need a big column with lots of internals, and somehow you have outsourced it to some other faraway country for the main body, and internals to another country or your own country so as to reduce transportation cost. In these cases truss comes handy in keeping the two in proper dimension ... all you need is to bring dimensions of bar from internal making company and give it to the shell making firm so that they can insert and keep things simple.A planar truss is one where all the members and nodes lie within a two dimensional plane, while a space truss has members and nodes extending into three dimensions.Tray Support Rings (TSR) and Bolting Bars: as already described, there is a huge chance of having internals and column designed at different places. In fact considering labor cost, patents, raw material availability and specialization there is a huge chance that your euipment will be from India, Korea or Japan and internals from US or Europe.In order that your trays fit and stay at their designated places you need these support rings to put trays at place and bolting bars to bolt them properly.

Saddles: you must be thinking in terms of ... is it the same thing that's there on a horseback ?? ..you probably may be right here. Saddles are used to support the equipment. Most of the big columns/reactors etc are installed vertically ... but manufacturing them in this fashion will cost a fortune. So manufacturers prefer to make them vertical. Now comes the roles of saddle, they keep these (most of the time cylindrical) structures in place and provides support while the equipment is switched into vertical position. Since the cranes lift it via a tailing leg (explained later), these saddles also provide a place on which equipment can slide upon.

Spreader Beam: These beams are meant to keep the ropes at a distance (so the name spreader :)) while the equipment is carried by crane, which typically has one point of contact and can lead to ropes getting closer and thus tipping the equipment. These spreader beams are specially designed keeping center of gravity and mass in mind (or at least it is supposed to be).Dress-up Beam: Now your equipment is ready and you are planning to ship it with saddles etc, just to mitigate the risk ... what you can do is put some extra bars at the bottom so that it dresses up the equipment and keeps it safe during transportation.

Tailing Leg: These are the extension to the equipment on which ropes are put on and carried via a crane so that the equipment can be rotated from horizontal to a vertical position. These needs to be firm and strong and be able to bear the extreme tensile stress thats come into picture once the equipment is rotated.Bumper Bar: There are always some external attachments to the equipment such as ladder, nozzles etc. and these can just bump into the ground while changing the orientation from horizontal to vertical. Well this is the time when bumper bars come into picture ... these are normally ring like structures lying at some height above the ground so that when these ladder are about to hit the ground they will rather bump into bumper bar and thus saving the equipment :)Scaffolding: Scaffolding is a temporary structure used to support people and material in the construction or repair of buildings and other large structures. It is usually a modular system of metal pipes or tubes, although it can be from other materials.

So the idea here should be to manufacture all the external equipments on the shell while its horizontal (quite cheaper), leaving only those external attachments which are close to the ground (or else they will hit the ground while orientation change). And install these attachments once equipment is vertical using scaffolding :). This way you will be saving some money by avoiding the bumper bar manufacturing.