Piping: Chapter 7
Pipe Fittings Part - 1
In this module, we will learn about different types of pipe fittings such as:
- Sweat fitting,
- ProPress fitting,
- T fitting, and
- Y fitting
We will also learn about flow changes that occur inside pipe fittings. Skip to quiz!
Sweat Fittings
Sweating is a type of fitting used to connect the pipes. A fitting is used to connect two pipes together. Sweating uses a connector to attach two pipes using heat.
Sweating a pipe and connector involves proper preparation of the pipe surface. Recall that before connecting two pipes using connector, you need to:
Remove rust using sandpaper, and
Remove burrs using deburring tool.
This is part of preparation process.
After preparation of pipe surface, a connector is attached to join the pipes. Connector is a copper tube to attach one pipe to another.
A connector can be a straight copper piece to increase the length of the pipe. It can also have a 90 degree bend to change the flow direction in a plumbing system.
Sweating is similar to soldering process. Soldering is a joining process in which two metals are joined by melting the solder. Sweating requires heating the connected ends of copper pipe that needs to be joined.
Recall that metal gets corroded. Corrosion can cause leakage in pipes. A flux is a chemical used in the soldering process for cleaning the pipe. Flux prevents corrosion of metal.
As you heat the metals to high temperature, the solder is applied. Melting point of the solder metal is less than the melting point of metal pipe. This causes solder to melt and stick the surface of pipe with connector.
After removing burrs and rust, you need to check if the copper piping and connector fit together before applying flux. Use a small paintbrush to cover the ends of your pipes and the insides of your pipe connector with a thin layer of flux.
Heat the assembly of pipe and connector. You will need to use soldering torch for this purpose. Hold your torch about 2 inches away from the assembly for 10 to 20 seconds to warm the part and the flux. As the flux melts, it begins to smoke slightly. This indicates that the pipe is ready for soldering.
Apply solder metal to junction of connector and piping. Solder melts and sticks the two metals.
ProPress Fittings
ProPress is a type of fitting used to connect two pipes. We will have to force the fitting into the piping to make the connection. This eliminates the need to solder, braze, thread, or weld the joint.
ProPress uses a fitting that has an O-ring inside. O-ring is donut shaped rubber that is used to seal the piping. It is placed into a groove present in ProPress fitting.
A ProPress tool is to compress the fitting. When the fitting is compressed, the O-ring gets squeezed between two surfaces of pipes. There is no more clearance for the O-ring to move. It firmly attaches the piping with the fitting.
Recall that proper preparation of the surface is necessary before applying fittings. Rough pipe edges can damage the O-ring inside the ProPress fitting. Use a deburring tool to smooth out the edges of the pipe.
Insert the ProPress fitting completely inside the pipe. This is to ensure the proper depth at which the copper tubing is inserted into the ProPress fitting. Mark the tubing at correct depth to provide reference stop line before applying fitting.
Insert the ProPress fitting onto the tubing end. Make sure fitting does not slide past the mark while applying. Place the ProPress tool over the fitting. As the tool is pressed, the fitting is compressed on the pipe.
Remove the tool from the made joint. Inspect the joint visually to verify that all joints have been attached firmly.
T Fitting
Tee type fitting, also known as T fitting, is used to connect piping which is in T-shape. It has one inlet and two outlets. The outlets are arranged at 90 degrees to the main line connection or inlet. Tee fitting is used to connect pipes at a right angle to inlet pipe.
Tees are made in various sizes of equal and unequal length. The equal tee is most commonly used. If three sides of T fitting are equal, then it is called equal T fitting. Unequal T fitting has unequal sides.
Tees are made in various sizes of equal and unequal length. The equal tee is most commonly used. If three sides of T fitting are equal, then it is called equal T fitting. Unequal T fitting has unequal sides.
Think about a car car that needs to turn to left or right at a 90-degree. It will have to slow down because resistance is more. Similarly, the water flowing from the inlet of T fitting to the outlet encounters resistance to flow.
Turbulence is irregular, unsteady movement of fluid particles. Notice that as the fluid flows past the 90 degrees bend, the blue particles are seen moving backwards. This turbulence happens due to sudden change in flow direction.
T fitting is required when you want to join two pipes together and alter flow direction at the same time. Pipe Tees are widely used in various commercial and industrial application. This includes:
Chemical processing, and
Petroleum
For example, your house is equipped with two basins. If you attach T fitting inlet to water supply line, it will alter the direction into two outlets. One end of pipe will go to the basin in the bathroom and other end to the kitchen.
V Fitting
Y fitting is similar to the T fitting. It resembles the shape of the alphabet “Y”. It also has one inlet and two outlets. The only difference is that the two openings are at an angle of 45 degrees with respect to each other. This allows one pipe to be joined to another at an angle of 45 degrees.
The Y fitting can take various shapes. They are classified as:
Standard Y fitting
Compact Y fitting
The only difference is in their shape.
Standard pipe Y, exactly in the shape of the alphabet “Y” in a horizontal position. The compact pipe Y is a pipe wye in a vertical position with three branches. Both fittings allows one pipe to be joined to another at a 45 degrees angle.
Recall that the angle is less in Y fitting compared to T fitting. This makes the particles to move gradually while changing direction of flow in Y fittings. This will cause less resistance to flow.
Think about a car on a road that further divides into two roads. It won’t have to take a sharp turn to take one of the two divided roads. This is because resistance is less compared to a 90 degrees turn. As the resistance to flow is less, fluid travel smoothly with low frictional loss and very low turbulence.
The round balls indicates the fluid particles. Notice that the fluid particles starts to flow from inlet of Y fitting. They move smoothly from inlet to two outlets. This is because there is no turbulence.
Y fitting is used in regulators connected to soldering gas cylinders. Pipe tees are widely used in various commercial and industrial application. This includes:
Chemical processing, and
Petroleum industry
Sweating is similar to soldering process. It uses a connector to attach two pipes using heat.
ProPress is forcing the fitting into the piping to make the connection.
T fitting has one inlet and two outlets. The outlets are arranged at 90 degrees to the main line connection or inlet. Y fitting also has one inlet and two outlets. The only difference is that the two openings are at an angle of 45 degrees with respect to each other.
Pipe Fittings - Part 2
In this module, we will learn about different types of fittings such as:
- Elbow fittings,
- Cross fitting,
- Couplings, and
- Flexible hoses for connecting pipes.Skip to quiz!
Elbow Fitting
Elbow is type of fitting used to connect two pipes with each other. With the help of an elbow, the direction of liquid is changed. 90 degrees elbow is used for 90 degrees change. For 45 degrees change in direction, you will use 45 degree elbow.
Fluid particles also pass slowly through a 45 degree elbow but faster than through a 90 degree elbow. This allows fluid to travel smoothly with low frictional loss and very low turbulence. The round balls indicates the fluid particles. Notice that the fluid particles starts to flow from inlet of 90 degree elbow fitting. They move smoothly through the elbow bend without turbulence.
Elbow fittings are connected to drainage pipes used for draining and supplying water to your home. They are also used in flow lines for gases, fluids in industrial processes such as medical, and construction.
Cross fitting
Cross fittings is used to connect four pipes. It is also called a cross branch line or a four-way fitting. This fitting has one inlet and three outlets.
Cross branch line is similar to T fittings. Flow from inlet of cross fitting suddenly changes direction. Due to sudden change in direction, there will be more resistance to fluid particles. This results in frictional loss and turbulence in the fitting.
A pipe cross fitting is used in the place where four pipes meet together. Pipe cross are widely used fire sprinkler. They are also used in industrial applications including:
Chemical processing,
Petroleum, and
Gas distribution lines
If you use cross fitting for high temperature, they tend to deteriorate. For example, waste heat recovery pipes in industries have high temperature. Avoid using cross fitting for such applications.
Coupling
Pipe coupling is a very short length of pipe or tube. It has threads at one or both ends. Pipe coupling allows two pipes of equal or different sizes to be joined together. This helps to extend length of pipe.
Pipe couplings are also useful if the pipe is broken or leakage occurs. Broken leaky end of pipe can be replaced using pipe coupling.
There are two types of coupling available.
Compression coupling, and
Slip coupling
Compression coupling is connected between two perfectly aligned pipes. It prevents leakage by the arrangement of gaskets or rubber seals on both ends of pipe.
We can fix long length damaged pipe by slip coupling. The length of slip coupling is adjustable because it has a movable piston inside. This makes us extend the coupling and we can use them for fixing broken pipes of varying length.
As seen in the video, slip coupling is easier to install. We slide two pipes into each end of slip coupling. We need to push pipe from one end and slide it until it stops getting in. Then, we need to adjust the slip extender to properly fit other end of pipe.
Common application where we use couplings are:
For connecting pipe of same or different material, and
For making quick piping repairs.
Flexible Hose
A flexible hose is also called a braided hose. The braid is made by weaving stainless steel wires on the periphery of a flexible hose.
Flexible hoses are used to transfer a high pressure fluids including gas, water and chemicals. The braid prevents elongation of flexible hose under pressure. This protects the flexible hose inside the braid.
A flexible hose is normally located under your kitchen sink. They are very useful for connecting the water supply from the sink to the drainage pipe.
Elbow is type of fitting used to connect two pipes with each other. Cross fitting has one inlet and three outlet. Pipe couplings are useful to extend length and repair leakages in the pipe. Flexible hoses are used to transfer a high pressure fluids including gas, water and chemicals.
Question #1: What is used to connect two pipes using sweat fitting?
Sweat
Connector
Reducer
All of these
Scroll down for the answer...
Answer: Connector
Connector is used in sweat fitting. Connector is a copper tube to attach one pipe to another.
Question #2: Sweating is similar to which process?
Brazing
Welding
Soldering
Swaging
Scroll down for the answer...
Answer: Soldering
Sweating is similar to soldering process. Sweating requires heating the connected ends of copper pipe that needs to be joined.
Question #3: ProPress fitting is forcefully making connection using heat.
True
False
Scroll down for the answer...
Answer: False
In ProPress fitting we need to force the fitting into the piping to make the connection. This eliminates the need to heat, solder, braze, thread, or weld the joint.
Question #4: ProPress fitting is faster than other pipe fitting processes.
True
False
Scroll down for the answer...
Answer: True
ProPress fitting is faster than other pipe fitting processes. This makes them suitable for quick repair work.
Question #5: T fitting has one inlet and more than two outlets.
True
False
Scroll down for the answer...
Answer: False
T fitting has one inlet and two outlets. The outlets are arranged at 90 degrees to the main line connection or inlet.
Question #6: Y fitting can be replaced by T fitting in a pipe.
True
False
Scroll down for the answer...
Answer: False
Y fitting also has one inlet and two outlets similar to T fitting.
They differ in angle of outlets. So, cannot be replaced.
Question #7: Which of the following fittings has one inlet and two outlet? (select all that apply)
Tee (T)
ProPress
Wye (Y)
All of these
Scroll down for the answer...
Answer: Tee (T)
Wye (Y)
T and Y fitting has one inlet and two outlets.
ProPress is type of fitting used to connect two pipes with each other.
Question #8: Which of the following fittings is used to connect two pipes with each other?
Tee (T)
Elbow
Wye (Y)
All of these
Scroll down for the answer...
Answer: Elbow
Elbow is type of fitting used to connect two pipes with each other.
T and Y fitting has one inlet and two outlets.
Question #9: Which of the following fittings is used to connect four pipes?
Tee (T)
Elbow
Wye (Y)
Cross
Scroll down for the answer...
Answer: Cross
Cross fittings is used to connect four pipes.
Question #10: What is the use of coupling? (select all that apply)
To connect one inlet to two outlets
Extend length of pipe
Repair leakage
Connect the pipe
Scroll down for the answer...
Answer: Extend length of pipe
Repair leakage
Connect the pipe
Pipe couplings are useful if the pipe is broken or leakage occurs.
They are also useful to extend length of pipe and connect two pipes.
Question #11: What is the use of flexible hose?
To connect one inlet to two outlets
To transfer a high pressure fluids
To connect three inlet to one outlet
To connect threaded piping
Scroll down for the answer...
Answer: To transfer a high pressure fluids
Recall that flexible hoses are used to transfer a high pressure fluids including gas, water and chemicals.
The braid prevents elongation of flexible hose under pressure.