It has to do with the design of the bolts. The reason that head of the bolt is oval in shape. The head of a bolt fit flush into the bar and set in opposing sets is so that a piece of dragging equipment will not shear off all the bolts in a joint but rather the just the nuts one side. As a result if the hole is not oval on one side there would be no way to tighten or loose the bolts in a joint.
Second Answer: They would be oval shapes so when contraction or expansion happens they wont snap.
No. Stainless Steel will resist contamination from the aluminum when they are used together.
Pitting is when there are small holes starting to appear in steel often caused by corrosion/rust
Steel is suitable for the rails, as it's hard enough to let steel wheels roll on it with minimum resistance, yet tough enough not to shatter. Sleepers doesn't have to be wood, they can be med of concrete as well. But before concrete, wood was a good choice. Strong enough, inexpensive enough and easy enough to work with.
Usually by bolting or welding them.
Yes and no. They leave the steel casing in the hole, and usually fill it with lean cement.
Supports are Southern Yellow Pine and track is Douglas Fir. All of this is tied together with steel bolts/rails/plates/beams.
Yes. If the hooks were in wooden side rails they were held in most likely by pins, if they tore out of the wood the wood will need to be replaced before repairing the rail. If the rails are steel they were held in by rivets, drill out the broken rivet(s) and replace them with short grade 5 bolts and nuts torqued down very tightly. Pins in wooden rails can similarly be replaced with bolts, use washers to keep the bolt head and nut from digging into the wood. If the hooks "slipped out" I'm assuming the rails are wooden. the pins would be visible(or the holes where the pins were) on the inside edge of the rail. The assumption is that the pins slid out of the holes. Find the holes, and using the correct sized drill bit drill them through the side board so that grade 5 bolts can be inserted through, to hold the hooks in place. [regular grade 3 bolts cannot handle the load placed on them from these hooks.]
The most common use for stainless steel bolts is to hold parts together. You may find stainless steel bolts in use on such common household features as plumbing, woodworking and more.
Rails are made of steel
A number of anchor bolts / hold down bolts can be "caged" together so that critical measurements are maintained when the steel is cast into the concrete slab - which is important for dealing with prefabricated structural steel and such. Typically, several anchor bolts / hold down bolts are connected by steel bracing and the assembles "cage" is welded together. See this link: http://www.damsteel.com.au/products/caged.html Hope this helps.
Steel wool... Or maybe just steel with many holes in it...
Railroad Tracksrails
Rails, usually made out of steel.
The steel wheels run along the steel rails. The Rails themselves used to be bolted together with plates, and each section of rail was 39 feet long. Modern welded rail still occasionally has bolted joints, but pieces of rail can now be more than a mile in length. The clickity-clack sound occurs when the steel wheel rolls across the small gap between each section of rail at the joint that's bolted together.
They were made of steel rails with wood ties.
Steel bolts are used while still hot to take advantage of thermal expansion properties for a tighter fit. When the bolts cool down, they contract, creating a strong and secure connection that prevents loosening over time. This method ensures a more reliable and durable joint than if the bolts were used at room temperature.
Because they will contract as they cool and that will pull the things being connected closer together.