Cast iron pipes form the backbone of drainage, waste and vent plumbing systems. These robust pipes have been around since 17th century and can still be found in many modern homes, commercial buildings and offices.
Pipes of any type, however, can break or corrode and need to be repaired. The most popular joint is the bell-shaped hub-and-spigot connection which seals with molten lead and oakum material.
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No-Hub Coupling
The No-Hub Coupling method of connecting cast iron pipe is a time-saving alternative that eliminates the need to melt lead and pour oakum into the joint. Furthermore, this process is straightforward to execute with minimal labor and equipment requirements.
Before no-hub couplings were invented, plumbers had to use lead and oakum in order to connect hub and spigot cast iron soil pipe into fittings. This costly and time consuming process necessitated that the plumber be well trained and experienced before they could do the job correctly.
Today, No-Hub Coupling has become a go-to solution for plumbing contractors since it eliminates the need to use melted lead and oakum, as well as special tools like melting pots and burners that can be costly and hazardous to use.
This method saves time as there is no need to install an additional tee adaptor on the cast iron P-trap. This reduces cost of hardware and allows plumbers to choose cheaper traps if desired.
Moreover, the No-Hub Coupling can be installed on any diameter of cast iron pipe – even those that don’t fit into a standard hubless coupling. Constructed of an alloy shield and clamp assembly according to CISPI 310 requirements, this coupling provides superior flexibility.
No-Hub Couplings come in various types, each offering its own advantages and drawbacks. Some of the key advantages include low installation costs and superior corrosion resistance.
Additionally, this type of coupling comes in an extensive selection of torques and sizes, making it simple to find one that meets your requirements. When tight connections are necessary that won’t leak or burst, these couplings make for a reliable option.
When installing the No-Hub Coupling, it is essential to make sure the spigot end of the pipe is straight and aligned with its gasket. Doing this will prevent it from popping out of its housing. Furthermore, running water through it before installation gives an indication of whether or not everything works as expected.
Compression Fitting
Compression fittings are a type of pipe connector that creates an airtight seal between two pipes. They’re popular in many applications due to their ease of use and versatility; making them great for connecting plumbing tubing.
Compression fittings typically consist of three parts: the pipe, nut and compression ring. Once tightened against the pipe, the nut deforms the ring against it for a watertight seal.
Metal tubes are ideal for this type of connection as they can handle more pressure than plastic pipes. However, it’s essential to match the material of your pipe with the type of fitting. Furthermore, it’s essential to lubricate both threads on nuts and rings during installation; doing so will guarantee proper installation and tightening to your desired pressure level.
Another advantage of compression fittings is their ease of installation – no special tools or expertise is necessary! Furthermore, it offers a quick and economical means for connecting cast iron pipe.
It is recommended that you only use this connection method when a permanent or stationary connection is required. Furthermore, do not overtighten the compression nut and ring as this could cause damage and leaks.
Compression fittings typically consist of a nut and ferrule that press against the end of the pipe, followed by a compression ring inserted in its seat. Once tightened against the pipe, these components create an effective seal.
Compression fittings are commonly used, but they cannot provide sufficient lengthening capabilities for long pipes. As such, compression fittings tend to corrode faster than other connections due to this limitation.
Furthermore, compression fittings made of harder materials such as steel may experience galling. They may also rotate when tightened, leading to a leaky connection.
Rubber Boot
The Rubber Boot method of connecting cast iron pipe is an economical and straightforward solution to do so. This makes it a great option for residential homes or other structures with cast iron plumbing installed inside them.
Rubber boots are composed of either vulcanized rubber or natural rubber that’s permanently attached together using waterproof adhesive. This process ensures the boots are waterproof and scentless, making them ideal for outdoor work.
Rubber boots typically feature a thick upper that covers your entire foot from top to bottom, as well as collars and other components designed to protect it. The type of material used in their construction can affect the weight, warmth factor, durability and water-protection level of the boot.
Depending on the job you perform, you’ll require different kinds of rubber boots tailored to meet your specific requirements. Farmers, for instance, require robust footwear that offers maximum protection in harsh climates.
For light landscaping or lawn maintenance tasks around your home, a lighter pair of rubber boots may suffice. Furthermore, consider what kind of traction you require when selecting rubber boots.
When working at your job site, the type of outsole you use can make all the difference between a secure and comfortable walk and an uncomfortable, unproductive one. Rubber boots typically feature durable molded rubber outsoles with protruding rubber tips that shed mud and debris as you walk.
Some outsoles are self-cleaning, meaning they’ll be able to remove dirt and mud from the bottom of your shoes. Furthermore, these outsoles typically have lugs or cleats for extra traction.
These lugs or cleats come in a range of patterns and the size is determined by the work that needs to be done. The lugs are especially essential for providing traction on rocky terrain.
Another type of rubber boot is the steel-toe Wellington, which is usually required to wear for many industrial jobs in order to meet occupational health and safety regulations or insurance needs. These boots are constructed from strong neoprene and sometimes lined with insulating material; making them perfect choices in cold weather or when working near icy or cold water.
Rubber Union
Cast iron pipe has long been a go-to material in plumbing systems, especially drain-waste-vent (DWV) lines. For these purposes, its durability and resistance to extreme temperatures make it the ideal material. Furthermore, cast iron pipe is fire resistant and does not emit caustic fumes when burning.
Cast iron piping can be replaced with PVC piping. However, it’s essential to understand the distinctions between these two types of pipe fittings before beginning any project.
First, a PVC drain pipe must be slightly smaller in diameter than its cast iron counterpart. This will enable them to fit together securely and seal without leaks.
Next, apply a generous layer of PVC adhesive to both the cast iron pipe and PVC connector. Firmly press these pieces together, holding for several minutes for the glue to set.
Finally, attach the two ends of the coupling with stainless steel neoprene gaskets. Be sure that each end has a distinct diameter.
Once both ends are connected, tighten the neoprene gaskets using a ratcheting torque wrench. Now your new DWV line can be connected to the old one securely.
This method is an ideal choice for connecting cast iron to PVC, as it’s fast and straightforward. Plus, there won’t be any leaks or other complications with other connections.
Another method for connecting PVC to cast iron is with a mechanical joint fitting. This is an end cap-style metal sleeve that fits over the end of the plastic pipe and secures it using two stainless steel band clamps.
The primary distinction between this type of coupling and a union is that the latter allows for future disconnection of connected pipes for maintenance purposes, making them ideal for larger pipes or more permanent systems.
It’s an ideal solution for systems with frequent movement, such as tank inlets or outlet valves. This will prevent the connection from shifting and damaging either the union or pipes connected to it.