Shipping containers are prevalent in nearly every industry and used to transport goods to different countries. When delivering goods to customers or manufacturers, the cargo must reach its destination safely. Shipping containers are well-sealed and locked to prevent weather or foreign objects from damaging the goods inside.
Twist locks are simple devices that are inserted into holes on the top and bottom corners of a container. The locks are then twisted to secure them in place. It’s a pretty ingenious system when you think about it – and it’s all thanks to twist locks.
Complete Guide to Shipping Container Twist Locks
Twist locks are one of the most important components to keep the containers joined together. Shipping containers stack on top of each other, and twist locks are used to lock them into place.
What Are Shipping Container Twist Locks?
Shipping container twist locks are used as connection devices to keep these containers locked. Most shipping containers use a locking mechanism and corner castings to provide security to their cargo. They can either lock the container horizontally or vertically.
Are Twist Locks Safe?
Whether shipping containers travel by sea, road, or rail, twist locks have been standardized as the safest method to secure them during transportation. These locks meet ISO strength requirements meaning they can withstand high tension loads during transportation.
Furthermore, this locking mechanism features shock absorbers to absorb jolt and vibrations. All container locks should be cleaned, lubricated, and regularly, so they are safe to use for operation.
Mechanisms
Twist locks act as the male part of the connector, while corner castings are the female part of the connector. These locks are typically inserted through the hole and rotated 90 degrees to prevent the lock from being withdrawn. The castings are welded onto the container and don’t have any moving parts.
Some may have built-in mechanisms or levers that require tools to secure them in place. Additionally, some twist locks are permanently installed on the beds of semi-trailers or the deck of the container ships.
Applications
There are many applications for twist-locks. They can be used to lock up containers traveling by way of ships, vehicles, or trains. Additionally, these locks must also be used when handling and lifting containers using forklifts, side lifters, reach stackers, straddle carriers, and other types of container cranes.
Moreover, it can be applied to many trailer types such as:
- Low loaders
- road trailers
- tipping
- drawbars
- tank
- fixed
- multi-purpose
- machine carriers
- sliding boogie
Installation – How to Secure Shipping Containers with Twist Locks
Knowing how to install twist locks securely is important for the security and safety of the cargo. Follow these rules for installing the twist locks:
Container Securing Rules
- Place the cone-shaped top of the lock into any upper or lower corner castings.
- Rotate the lever to a 90-degree angle to lock it into your container’s corner casting.
- Once the twist-lock is installed, it can’t be separated from the casting.
Types of Twist Locks
It’s important to consider which form of twist-lock best suits your needs. There are many variations such as:
- horizontal locks
- dovetail twist locks
- manual twist locks
- tie down twist locks
- semi-automatic twist locks
- weld-on truck chassis flatbed twist locks
Horizontal Locks
Horizontal locks are designed to connect shipping containers side by side. They are unable to connect vertically. Position the lock onto the side of the container and twist. Then, connect the second container to the side of the lock to secure the two containers.
Dovetail Twist Lock
Dovetail twist locks are bolted onto a metal surface with the base and designed for flat surfaces. They also can be welded on top of any surface. Position the lock in a neutral position, then stack the container on top and twist into the lock position. This device locks from right to left and allows the container to stack vertically.
Best Dovetail Twist Lock: Mytee Products (4 Pack Sea Rail Bolt-On Dovetail Style Shipping Container Twist-Lock
We recommend the Mytee dovetail twist lock because of its high strength and load capacity. It’s made from heat-treated steel to handle extreme temperatures. Furthermore, it has a minimum break loads tension of 500 kN/ 420 kN, which defines the amount of tension or loading required to break the lock.
Manual Twist Lock (double-ended)
A manual twist helps the containers stack vertically on top of each other. It works with a left-to-right locking mechanism. Move the lock handle in a neutral position before loading the container onto the slot. Then turn the handle into a locked position.
The Mytee brand offers the best manual twist-lock in the market. Since it can sustain up to 2000 KN of compression force and 500 KN of tension pressure, it can stack and provide security to the heaviest shopping containers.
Best Manual Twist Lock: Mytee Products (4 Pack Sea Rail Shipping Container Manual Twist Lock Left-Right Handlocking Casting Steel - No Lever Required
Plus, the lock has been hot-dip galvanized to resist corrosion and prevent rust. Make sure to choose the right size that fits your container. A larger manual lock covers a bigger surface area, generating better stability and security.
Tie Down Twist Lock
Once the containers are in position, the tie-down twist lock is used to anchor the bottom container to the ground. Insert the tie-down twist-lock into the ISO bottom corner casting, then rotate it so that the bolt hole faces the ground.
The Chassis King tie-down twist lock is made from high-strength materials such as carbon steel, gray iron, and stainless steel. It features a gross operational weight of 22T.
Best Tie Down Twist Lock: Shipping Container ISO Tie Down Twist Lock - Storage Container Side Twist Lock Anchors Gray
Furthermore, it can be utilized on the top shipping container casting to enable structural elements to be tied down, such as roofs or aerials.
Semi-Automatic Twist Locks
Semi-automatically twist locks help the multiple containers stack on top of each other and are spring-loaded.
Compared to manual locks, these semi-automatic twist locks provide better security. That’s because the spring prevents accidental unlocking.
Once the container load is placed on top, the twist locks automatically lock. The mechanism connects the two containers’ top and bottom casting holes. You’ll need to pull the spring and release the lock to unlock it.
Best Semi-Automatic Twist Lock: BD-J1 Semi Automatic Twist Lock
The BD-J1 twist locks automatically when the top container is lowered onto the bottom. It has a breaking load tension of 500 kN and is approved for ISO ocean shipping containers.
Weld-on Truck Chassis Flat Bed Twist Lock
The weld-on truck chassis flatbed twist lock is used for sea freight industrial containers transported with a truck. It connects to the bottom of the container and not the side. The retractable mechanism works by pulling the handle and twisted into a locked or unlocked position.
Best Truck Chassis Flat Bed Twist Lock: Mytee Products (4 Pack Sea and Rail Shipping Container Manual Twist Lock for Chassis - Forged Steel - Can Be Welded or Bolted to A Chassis/Flatbed
This manual twist lock for chassis or trailer is bolted to a flatbed to secure containers. It has a minimum breaking load of 360 kN and is made from durable casting steel.
Conclusion
The security of containers loaded on a flatbed or trailer is incredibly important. Having knowledge of the different types of twist locks and how to install them will help you keep your items, goods, and products safe. Take what you’ve learned and choose the twist-lock that best suits your situation.
Last update on 2023-12-03 / Affiliate links / Images from Amazon Product Advertising API
