More from: turnbuckles

What is a Drop Forged Turnbuckle?

Any experienced lift master can tell you that a successful lift is facilitated by a long list of individual components. Lifting utilizes cables, slings, hooks, etc. One such component that doesn’t get talked about a lot is the turnbuckle. We will talk about it in this post, and specifically the drop forged turnbuckle.

In our industry, there are a lot of terms that the average person does not understand. That’s okay. As long as we and our customers speak the same language everything is fine. On the other hand, maybe you are not a lift master. Maybe you are a truck driver who has the pleasure of watching while a lift master gets cargo up onto the back of your trailer. We still want you to know what a forged turnbuckle is.

The Turnbuckle Explained

A turnbuckle is a type of fastener deployed for tensioning purposes. Also known as stretching screws and bottle screws, turnbuckles consist of two threaded bolts contained inside a metal frame with the flat ends facing one another. They can be eye bolts, hook bolts, or even eye and jaw bolts.

The secret to the turnbuckle’s usefulness is opposite threading. In other words, one bolt is threaded clockwise while the other is threaded counterclockwise. This allows the metal housing to be turned in a single direction to either increase or decrease tension. If the bolts were threaded in the same direction, this would not be possible.

When you turn a turnbuckle clockwise, it should increase tension by drawing the two bolts together. Turning it clockwise pushes the bolts apart, thus reducing tension. This simple mechanism makes it easy to control the tension on ropes, cables, and chains with very little effort.

Drop Forging a Turnbuckle

Drop-forged turnbuckles take their name from the process used to manufacture them. Mechanically speaking, they are no different from any other kind of turnbuckle.

Drop forging is a process that turns hot metal pieces into finished parts with specific shapes. If you are familiar with the image of an Old West blacksmith forming horseshoes out of molten metal, you already know what drop forging is.

In the modern era, manufacturing drop-forged turnbuckles requires a lot less human effort than fashioning horseshoes with a hammer and bare muscle. The process begins by cutting the metal to the desired size. It is then heated red-hot to prepare for the first step of forming its shape.

In some cases, the heated metal goes right into a die where weight and pressure form the initial shape. In other cases, the initial shaping is performed by hand before the piece goes into the die. It really just depends on manufacturer preferences.

Finishing the piece is a matter of putting it through a series of dies until it is shaped accordingly. The most important thing to know about drop forging is that the combination of heat, weight, and pressure is that which gives the finished product its strength. Drop forging not only shapes the piece, it strengthens the molecular composition at the same time.

The Right Tool for the Right Job

One thing we appreciate in learning about how things like drop-forged turnbuckles are made is that it gives us a greater understanding of the principle that there is a right tool for every job. Imagine being a lift master trying to adjust the tension on a sling without a supply of turnbuckles. How would you do it?

Turnbuckles are pretty simple in design yet quite effective for their intended purpose. They certainly belong in our rigging inventory here at Mytee Products.


Rigging Science: The Physics Behind the Block and Tackle

Mytee Products carries a full inventory of rigging supplies covering everything from blocks to turnbuckles and shackles. All of that is well and good, but sometimes it is helpful to understand the physics behind rigging principals. Understanding makes for safer lifts.

In light of that, we thought it might be interesting to discuss the physics behind the block and tackle principal. The block and tackle represents one of the easiest ways to lift extremely heavy loads with very little force. Block and tackle setups have been used for centuries by cultures all over the world.

The Block and Tackle Defined

A block and tackle isn’t a single piece of equipment. Instead, it is a particular kind of rigging set-up that includes multiple pulleys and some sort of means to lift the load – be it rope, wire, chain, etc. The most basic setup utilizes at least two pulleys with a rope or wire running between them.

The pulleys in a block and tackle system can be located close together or at a distance. Locations are chosen based on the nature of the lift. The pulleys on a crane might be close together while those in the warehouse rigging system are farther apart.

The Principle of Lifting Force

Physics dictates that a certain amount of force is required to lift a load off the ground. The heavier the load, the more force required. The lifting force has to be either equal to or greater than the weight of the load.

For example, imagine you are lifting a 200-pound load using a single pulley and a 200 ft. rope. You have to apply a minimum of 200 pounds of force in order to get the load off the ground. All 200 pounds will be carried by that single pulley. Also note that the amount of force you need is inversely related to the length of your rope.

If your rope is 100 feet long, more force will be required. The opposite is true if your rope is longer than 200 feet. What does this tell you? It tells you that a longer rope and more pulleys should require less lifting force from you.

Sharing the Load among Blocks

Remember that a block and tackle system utilizes multiple pulleys (or blocks) for lifting. Each of those blocks takes some of the weight of the load. So once again, let us assume a 200-pound load and two blocks in your system. Each block carries half the weight, or 100 pounds. Using the same 200-foot rope now means you only have to apply 100 pounds of lifting force instead of 200.

Introduce a third block into the system and you reduce the total weight carried by each block yet again. Instead of 100 pounds per block, you are now in the neighborhood of 70 pounds.

In theory, you can continue adding blocks and lengthening the rope to make your load even easier to lift. In practice though, there is a tipping point. Additional blocks and longer rope create resistance. Make your block and tackle system too big and the amount of resistance in the system could make it impossible to lift the load anyway. So there is a balance between distributing the weight and minimizing resistance.

Distributing the Load

The simplest way to understand the physics of a block and tackle system is to understand that each block in the system takes part of the load. It is all about load distribution. Greater distribution means less lifting force to get a load off the ground. That’s about it in a nutshell.