 | This article has multiple issues. Please help improve it or discuss these issues on the talk page . (Learn how and when to remove these template messages)
|
Lockrods are mechanical devices used to secure swing doors on the back end of trailers. They are used for semi-trucks, containers, and small specialty trailers.
Patented originally in 1912, the lockrod was first used to secure railroad boxcar doors. Today, sometimes confused with locking bars or bar locks, lockrods have evolved to secure virtually every trailer or container that has a swing door (a door that swings open and closed rather than rolls up). Roll up doors are sometimes used in place of swing doors on trailers that make shorter haul deliveries.
Swing doors are most commonly used on tractor-trailers (dry vans and refrigerated "reefer" vans), intermodal cargo shipping containers, certain rail cars that carry automobiles, and smaller utility trailers that haul cargo or livestock.
Miner Enterprises was the originator of the lockrod and owned patent #1,023,164.
In 1960, Miner Enterprises acquired White Welding in Kenosha, Wisconsin and renamed the product line Powerbrace America. Later the name was changed to Powerbrace Corporation, a subsidiary of Miner Enterprises. Powerbrace continues to manufacture lockrods, trailer door hinges, and security lock devices for trailer doors from its Kenosha plant.
Trailer doors are secured to the end frame (end wall) of the trailer to make sure the cargo doesn't shift and break down the door, and second, to keep the doors aligned properly by not allowing them to move up and down while in transit (racking). If racking occurs due to too much play between parts, the parts wear out and eventually will fail to secure the door.
The doors and end frame must hold the cargo securely while allowing the doors to swing free and be safely opened and closed with minimal effort. Depending on the size of the trailer, trailer end frame components typically consist of six to ten hinges, two to four lockrods, two trailer doors and the framework itself – all made of metal (usually steel, but sometimes aluminum).
A lockrod assembly consists of top & bottom cams that are welded to the rod/stick of tubing itself, along with a handle assembly. Keepers (usually sold separately), are the part that accepts the cam, and can be welded or bolted onto the end frame of the trailer and remain stationary to the endframe. Mounting hardware attaches the lockrod to the doors (also sold separately).
All trailer loading and unloading is done through the end frame of the trailer, which endures the highest forces. The top horizontal member is called a header. The bottom is referred to as the sill. The end frame is the action part of the trailer. The rest of the trailer is made up of the box that sits on the chassis, and includes the floor and running gear (wheels, brakes, lights, etc.).
Lockrods come in different lengths and thickness (rod diameter) depending on intended use. Heavy-duty models are one-inch in diameter and are usually made of steel, most often galvanized, but sometimes painted or electropolished for cosmetic reasons.
In lighter duty applications, such as smaller utility trailers, a ¾-inch diameter lockrod can be used; these can be made of steel or aluminum. In addition to the rod and handle, the cams and keepers metal matches that of the other lockrod parts. For example, if the lockrod were stainless steel, cams and keepers would be stainless to match. If galvanized lockrods, the cams and keepers would be made of galvanized steel to match. This metal match-up also minimizes corrosion that occurs when two dissimilar metals are in contact with each other.
Over the years, manufacturers have designed types of cams/keepers combinations to solve certain door alignment problems.
Powerbrace invented the zero-torque lockrod concept that became an industry standard. The main benefit of the design is that the cam goes past the center point so that the more pressure that's applied from the inside of the trailer doors (such as when animal weight is shifted against the door) the tighter the cams and keepers engage.
Refers to the ability of a lockrod cam to "reach" and engage the keeper (gather) while closing the door; this feature helps to overcome resistance from compression seals and warped doors.
A lockrod model with high door opening leverage, earning its name for its ability to open doors that are frozen shut.
A door is a hinged or otherwise movable barrier that allows ingress (entry) into and egress (exit) from an enclosure. The created opening in the wall is a doorway or portal. A door's essential and primary purpose is to provide security by controlling access to the doorway (portal). Conventionally, it is a panel that fits into the doorway of a building, room, or vehicle. Doors are generally made of a material suited to the door's task. They are commonly attached by hinges, but can move by other means, such as slides or counterbalancing.
In woodworking and construction, a nail is a small object made of metal which is used as a fastener, as a peg to hang something, or sometimes as a decoration. Generally, nails have a sharp point on one end and a flattened head on the other, but headless nails are available. Nails are made in a great variety of forms for specialized purposes. The most common is a wire nail. Other types of nails include pins, tacks, brads, spikes, and cleats.
Rebar, known when massed as reinforcing steel or reinforcement steel, is a steel bar used as a tension device in reinforced concrete and reinforced masonry structures to strengthen and aid the concrete under tension. Concrete is strong under compression, but has low tensile strength. Rebar significantly increases the tensile strength of the structure. Rebar's surface features a continuous series of ribs, lugs or indentations to promote a better bond with the concrete and reduce the risk of slippage.
A fastener or fastening is a hardware device that mechanically joins or affixes two or more objects together. In general, fasteners are used to create non-permanent joints; that is, joints that can be removed or dismantled without damaging the joining components. Steel fasteners are usually made of stainless steel, carbon steel, or alloy steel.
A dump truck, known also as a dumping truck, dump trailer, dumper trailer, dump lorry or dumper lorry or a dumper for short, is used for transporting materials for construction as well as coal. A typical dump truck is equipped with an open-box bed, which is hinged at the rear and equipped with hydraulic rams to lift the front, allowing the material in the bed to be deposited ("dumped") on the ground behind the truck at the site of delivery. In the UK, Australia, South Africa and India the term applies to off-road construction plants only and the road vehicle is known as a tip lorry, tipper lorry, tipper truck, tip truck, tip trailer or tipper trailer or simply a tipper.
A doorstop is an object or device used to hold a door open or closed, or to prevent a door from opening too widely. The same word is used to refer to a thin slat built inside a door frame to prevent a door from swinging through when closed. A doorstop (applied) may also be a small bracket or 90-degree piece of metal applied to the frame of a door to stop the door from swinging (bi-directional) and converting that door to a single direction. The doorstop can be a separate part or integrated with a hinge or door closer.
A gas cylinder is a pressure vessel for storage and containment of gases at above atmospheric pressure. High-pressure gas cylinders are also called bottles. Inside the cylinder the stored contents may be in a state of compressed gas, vapor over liquid, supercritical fluid, or dissolved in a substrate material, depending on the physical characteristics of the contents. A typical gas cylinder design is elongated, standing upright on a flattened bottom end, with the valve and fitting at the top for connecting to the receiving apparatus.
A derrick is a lifting device composed at minimum of one guyed mast, as in a gin pole, which may be articulated over a load by adjusting its guys. Most derricks have at least two components, either a guyed mast or self-supporting tower, and a boom hinged at its base to provide articulation, as in a stiffleg derrick. The most basic type of derrick is controlled by three or four lines connected to the top of the mast, which allow it both to move laterally and cant up and down. To lift a load, a separate line runs up and over the mast with a hook on its free end, as with a crane.
A flatcar (US) is a piece of rolling stock that consists of an open, flat deck mounted on a pair of trucks (US) or bogies (UK), one at each end containing four or six wheels. Occasionally, flat cars designed to carry extra heavy or extra large loads are mounted on a pair of bogies under each end. The deck of the car can be wood or steel, and the sides of the deck can include pockets for stakes or tie-down points to secure loads. Flatcars designed for carrying machinery have sliding chain assemblies recessed in the deck.
Dunnage is inexpensive or waste material used to load and secure cargo during transportation; more loosely, it refers to miscellaneous baggage, brought along during travel. The term can also refer to low-priority cargo used to fill out transport capacity which would otherwise ship underweight.
A swivel is a connection that allows the connected object, such as a gun, chair, swivel caster, or an anchor rode to rotate horizontally or vertically.
A latch or catch is a type of mechanical fastener that joins two objects or surfaces while allowing for their regular separation. A latch typically engages another piece of hardware on the other mounting surface. Depending upon the type and design of the latch, this engaged bit of hardware may be known as a keeper or strike.
A bicycle trailer is a motorless wheeled frame with a hitch system for transporting cargo by bicycle. It can greatly increase a bike's cargo capacity, allowing point-to-point haulage of objects up to 3 cubic metres in volume that weigh as much as 500 kg. However, very heavily loaded trailers may pose a danger to the cyclist and others, and the voluntary European standard EN 15918 therefore suggests a maximum load of 60 kg on trailers without brakes.
A fitting or adapter is used in pipe systems to connect sections of pipe or tube, adapt to different sizes or shapes, and for other purposes such as regulating fluid flow. These fittings are used in plumbing to manipulate the conveyance of fluids such as water for potatory, irrigational, sanitary, and refrigerative purposes, gas, petroleum, liquid waste, or any other liquid or gaseous substances required in domestic or commercial environments, within a system of pipes or tubes, connected by various methods, as dictated by the material of which these are made, the material being conveyed, and the particular environmental context in which they will be used, such as soldering, mortaring, caulking, Plastic welding, welding, friction fittings, threaded fittings, and compression fittings.
A semi-trailer is a trailer without a front axle. The combination of a semi-trailer and a tractor truck is called a semi-trailer truck.
A large flat bed truck transports huge tires destined In [California] A flatbed truck is a type of truck the bodywork of which is just an entirely flat, level 'bed' with no sides or roof. This allows for quick and easy loading of goods, and consequently they are used to transport heavy loads that are not delicate or vulnerable to rain, and also for abnormal loads that require more space than is available on a closed body. Flatbed trucks can be either articulated or rigid.
An espagnolette is a locking device, normally mounted on the vertical frame of a French door or casement window. A handle or knob is connected to a metal rod mounted to the surface of the frame, about a metre above the floor. Operating the handle rotates the rod, which has hooks at each end that fit into sockets at the head and sill of the opening. This type of lock is often used on semi-trailer trucks to fasten the rear doors. It can be identified by the use of a round bar, instead of a half-round bar used on a crémone bolt.
Three-point locking, or a multipoint lock, is a locking system installed in cabinet or locker doors to enable more secure locking. Whereas in single-point locking, the door on a cabinet locks only at the point where the key is turned, halfway up the edge of the door, three-point locking enables the top and bottom of the door to be simultaneously secured. This is accomplished by attaching two long steel rods to the lock on the inside of the door, which extend vertically upwards and downwards: when the lock is turned, the rotary movement of the latch on the inside of the door translates to vertical movement in these rods, with the result that the upper rod moves upwards by an inch or so, and the lower rod moves downwards similarly. This causes the ends of the rods to move through small holes in the flanges at the top and bottom of the door, resulting from the metal of the door being turned inwards, and the rods then move a short distance into holes in the metal surrounding the door. This effectively immobilizes the top and bottom of the door, and greatly increases the security of the door-locking compared to a door with only single-point locking.
A cam and groove coupling, also called a camlock fitting, is a form of hose coupling. This kind of coupling is popular because it is a simple and reliable means of connecting and disconnecting hoses quickly and without tools.
Metal expansion joints are compensating elements for thermal expansion and relative movement in pipelines, containers and machines. They consist of one or more metal bellows, connectors at both ends, and tie rods that depend on the application. They are differentiated according to the three basic types of movement: axial, angular and lateral expansion joints. Expansion joints have usage in various sectors, like energy production, paper industry, chemical industry, water treatment, oil and gas. Expansion joints can be used wherever thermal movements or vibration occurs in pipelines.
| Fundamental concepts |  | |
|---|---|---|
| Components and hardware | ||
| Keys | ||
| Mechanical locks | ||
| Electronic locks | ||
| Other lock types | ||
| Lock picking | ||
| Security alarms |
| |
| Miscellaneous | ||
