D&R Metal Industry  – China’s Leading Brass Fitting Manufacturer

D&R Metal Industry is one of the reliable sources of brass fittings in China. We are in the market for more than 15 years now and are glad to become your trusted partner in your business. D&R delivered thousands of brass fittings not just in China but worldwide.

In terms of the quality of our brass fitting, you can guarantee that it is 100% high quality and only using top-rated materials in manufacturing our brass fittings.

D&R Metal Industry brass fitting is lead free and made of solid brass. It is heavy duty and can withstand different environments and weather conditions and also it is rustproof.  The best thing about brass fitting is that it can last for 80 to 100 years.

Brass Elbow Fittings

Brass fitting is usually used for pipes, plumbing, and others. In the construction industry, they prefer to used brass fitting for their plumbing and water system because it is durable, can stand or tolerate high levels of temperature compared to other fittings. When it comes to versatility you will not regret our products.

Here in D&R Metal Industry, you can find all types of brass fitting that perfectly fit your business needs. All sizes are here to always fulfill your required brass fittings for your plumbing projects.

At D&R Metal Industry we pushed ourselves to bring and produced world-class quality brass fitting at a lower cost with extraordinary services with our valued clients. As the reliable supplier and trusted manufacturer of brass fitting, we always ensure that our products leave satisfied with our customers by providing them one-of-a-kind products.

Brass Flare Fittings

You can make sure that you can always get the best one, the solid one, and can stand out to other most of the time.

In D&R Metal Industry, we manufacture not just brass fitting but also other types of brass fittings and valves. For more information and inquiry, send us a message.

Brass Fitting: The Ultimate Guide

Plumbing involves two major components, pipes and fittings. The former is easy to understand.

However, the latter may be confusing since they come in various designs and types. In layman’s language, a fitting is a piece of equipment that connects two pipes at a certain angle.

The sole aim of this guide is to walk you through fittings, specifically brass fittings.

Brass Fitting

Benefits of using Brass Fitting in Pipe Systems

Apart from the fact that Brass fittings are widely used, they come with a lot of benefits. Below are some reasons you should face the direction of brass fittings the next time you are looking for fittings.

• Durability – Brass fittings are proven to have a long lifespan. As such, they are used in long-term plumbing projects both domestically and industrially.

In addition, brass is a heavy-duty metal, and it does not crack or disintegrate easily.

• High Malleability – Compared to other metals, such as steel and iron, brass is more malleable. This property enables the modification and flexibility of brass fittings in various projects.

Consequently, brass fittings can easily be molded to serve a particular plumbing need.

• High-temperature tolerance – Brass fittings can withstand high pressure and temperature condition. They have been ranked among the best fittings to transport hot water due to their outstanding conductivity.

Notably, depending on the quality, brass fittings are mostly fire-resistant.

• Corrosion and rust resistance – Rusting and corrosion greatly impact the lifespan of a fitting. They lead to wear and tear, leading to reduced lifespan.

Luckily, brass fittings are both corrosion and rust-resistant due to their composition, making them more ideal.

Also, our brass fittings are majorly composed of copper and not zinc, which causes corrosion through dezincification.

• Versatility – There are many brass fittings you can choose from, depending on design and size. This benefit is tied to the malleability nature of brass which allows easy and fast molding.

They also have various finishing, some of which are attractive and can be used in exposed areas.

Uses of Brass Fittings

Brass fittings are primarily used in plumbing pipes to carry products such as slurries, water, chemicals, flammable gases, etc.

These fittings come in various shapes, sizes, and treads, making plumbers prefer them for different plumbing needs.

Additionally, brass fittings can also be found in automotive parts such as fuel line valves, hose ends, and air brakes.

Lastly, you will encounter brass fittings in fittings used in refrigerator coolers, compression fittings, and ballcock adapters.

  Limitations of using Brass Fitting

The limitations of brass fittings lie in their composition. Yellow brass (having a higher zinc concentration) is more susceptible to corrosion.

The brass fitting can undergo corrosion through a process known as dezincification which eliminates the zinc component from the brass fitting.

As such, yellow brass fittings (which are the most common) can only be used in a less corrosive environment.

In simpler terms, the fluids passed by the fitting must be low in chlorine concentration. This is because chlorine offsets the dezincification process.

Secondly, when brass fittings undergo dezincification, it isn’t easy to notice.  As such, the structure of the brass fitting weakens gradually.

By the time you notice this, your brass fitting will be leaking, and you will be forced to carry out a replacement.

Lastly, dezincification results in the formation of zinc oxide. This is a white powder, which clogs the pipe and entire system over time.

Factors Determining Brass Fitting Prices

The key factors that determine how much a brass fitting will cost you include:

• Size – The larger the brass fitting, the more money you will have to part with.
• Quality – A quality brass fitting is one with more copper and less zinc composition. This will make the brass fitting more resistant to corrosion thus more expensive.
• Mode Of Purchase – Importing a small number of brass fittings will be more expensive than bulk purchase, which is characterized by discounts.
• Thickness – A thick brass fitting translates to more usage of brass in the manufacturing process, thus a higher price tag.
• External Factors – Factors such as an increase in copper or zinc price will directly or indirectly affect the price of the brass fitting.
• Design – This encompasses the structure and finishing of the fitting. The more complex the structure and the more exquisite the finishing is, the more the cost is attached to the brass fitting.

How to Test Quality of Brass Fitting

Quality test for brass fitting, similarly to other fittings, is done during manufacturing. However, some tests are mandatory, while others are done upon request by the purchaser.

Outlined are the typical tests carried out to ensure the quality of a brass fitting:

Hydrostatic Test

Though not a mandatory test, the fittings are examined to gauge their pressure threshold. To bypass this, manufacturers may include hydro tested shells when manufacturing the fitting.

Proof Test

This includes a burst test where the fitting is artificially pressurized. If the fitting does not burst under the recommended pressure rating, it is regarded safe for use.

Destructive Test

To ascertain the strength of the fitting, a destructive test is carried out. These tests include tensile test, hardness test, burst test, and impact test.

Either of these tests can be used to check the strength of the brass fitting.

Non-Destructive Test

On the other hand, the non-destructive test checks the soundness of a brass fitting. These tests include ultrasonic, magnetic particle tests, and liquid penetrant tests.

Metallurgical Tests

To ensure that the fittings comply with internationally acceptable standards, metallurgical tests are carried out. It includes microanalysis, which deals with the chemical composition, and macro analysis dealing with the outer part, such as weld.

Special Tests

Special tests help to check the corrosion resistance of a brass fitting. Such tests include Intergranular Corrosion (IGC) test, Hydrogen Induced Cracking (HIC), Sulfide Stress Cracking (SSC).

Visual Test

Lastly, you can visually examine the brass fitting quality by checking for any imperfections such as dents, porosity, undercuts, die marks, cracks, etc.

Notably, most of these tests are done in your absence as the buyer. However, as proof of test, the brass fittings will come with markings.

Quality test markings include the manufacturer’s logo, size of the fitting, material code, ASTM codes, and standard fitting compliance codes.

Types of Brass Fitting to use in Piping Systems

Types of Brass Piping Fitting

Brass Elbow

Similar to a human elbow that allows you to bend your arm, the brass elbow fitting permits the bending of a pipe. In addition, brass elbows (“ells”) help change a piping system’s direction.

Commonly, a brass elbow has but is not limited to, a 45^o or a 90^o bend. Brass elbows come in two main diameter/radius types; 1D (Short radius) and 1.5D (Long radius).

Additionally, they have threaded connectivity. A great example of an elbow fitting is the one extending from your shower wall. It is the point at which the showerhead connects.

As earlier mentioned, these fittings help to change the direction of the piping system. Notably, they change the direction in various angles depending on their design as discussed below:

1. 90^o Brass Elbow – Installed between the pipes to change the direction at an angle of 90 degrees.
2. 45^o Brass Elbow – Installed between the pipes to change the direction at an angle of 45 degrees.
3. 180^o Brass Elbows – They are also referred to as returns since they change the pipe direction at an angle of 180 degrees, a complete turn.

Brass Union

Brass unions come in various designs and sizes. Their primary role is to join or “unite” two pieces of tubing or pipe.

Consequently, they are shorter compared to other fittings. They are designed to be easily removed, thus ideal where the pipe’s dismantling is often done.

Commonly, brass union ends are threaded, but there are also some with socket weld ends. A brass union majorly consists of a female end, a male end, and a nut.

The male and female ends are the point of the connection while the nut provides the necessary pressure to seal the joint.

Brass Tee

The brass tee fitting has a 90^o branch at the center, giving it a “T” shape. Brass tees can be classified according to the diameter of the branch as follows:

• Straight Brass Tee – It has a similar diameter size to the header (run) pipe – the pipe that joins the branch.
• Reducing Brass Tee – The branch has a smaller diameter than the header/run pipe.

Also, they can be classified in terms of their design, i.e.

• Barred brass tee (Scrapper) – It has welded bars that restrict free passage from the header/run pipe.
• Wye brass tee (Lateral) – Unlike the other brass tees with the branch situated at a 90^o angle, the wye tee’s branch is at 45^o. Its design helps minimize turbulence and friction that could interrupt the flow.

Brass Reducer

As the name suggests, brass reducers change (reduce) the size of the pipe. As such, they have one end same as the pipe’s diameter, and the other end, which is smaller.

There are two major types of reducers, which have different functions:

• Conical/Concentric brass reducers – They assume the shape of a cone, and the center of both its ends lies on the same axis. They are applied where the center of both the small and the larger pipe are to be maintained.
• Eccentric brass reducer – Unlike the conical reducer, the eccentric reducer has its ends on a different axis.

Its major function is to help maintain the bottom of pipe (BOP) elevation of the piping system. Meaning it helps maintain one part of the outside surface.

Brass Bends

Brass bends are used in a  piping system that requires pigging. They have low pressure drop due to their smooth change of direction and long radius, making pigging possible.

The sizes of brass bends are measure in terms of ‘D,’ with 5D and 3D being the most common sizes.

Brass Cross

The brass cross fitting assumes a cross structure, i.e., it has four openings. Consequently, it is sometimes referred to as the four-way pie fitting.

They either have three inlets and one outlet or three outlets and one inlet and are mostly socket weld.

However, unlike the other fittings, they are not commonly applied in all piping systems. Their usage is mostly in firewater sprinklers piping lines.

Brass Caps

Brass caps are fittings applied at the dead-end of a piping system. They cover the end of pipes, obstructing any flow.

They are mostly used in systems that are not yet complete, i.e., they temporarily cover the headers for future connections.

 Brass End Cap Fitting

Brass Stub Ends

Brass stub ends are but weld to the pipe to allow for a lap joint flange connection. Stub ends are necessary for this type of flange, making them double up as part of the flange and a fitting.

Brass Coupling

The brass coupling performs a similar role to the brass union, i.e., joining two pieces of pipe or tubing. The designs and sizes of brass coupling and brass tubing are somewhat similar.

However, since brass couplings are mostly welded to the pipes or tubing, they are permanent, unlike brass unions, which can be easily removed.

Brass couplings can be classified as:

• Full Coupling – for connecting small bore pipes. It has a thread or socket end on both sides.
• Half Coupling – for connecting a small-bore branching from a large pipe or a vessel. It has a thread or socket end on one side.
• Reducing Coupling – for connecting two pipes of different sizes. Both ends have threads or sockets that differ in size.

Brass Swage Nipple

The brass swage nipple is a fitting for fittings. It has male threaded ends on one end or both ends.

Also, it is useful in pipes, valves, and hose connections. However, their usage is limited to low-pressure conditions.

Brass Saddle

Unlike the other fittings that join pipes, tubing, and valves, a brass saddle offers support to them. The pipe is placed on top of the saddle, which takes the force exerted by the pipe.

Brass saddles help prevent your pipe from breaking due to the weight exerted by the fluid being transported.

Common End Connections for Brass Fittings

Some of the most common end connections include the following:

Butt Weld

It is a simple welding design that involves joining the brass fitting to the pipe or tube and welding along the joint. They are defined by the ASME B16.11.

To be butt weld a brass fitting, the surfaces of the fitting and pipe or tube have to be on the same plane. This will enable the weld metal to remain on the same plane as the surfaces creating no overlapping.

The brass fitting can be butt welded in four major ways; single-sided full and partial penetration and double-sided full and partial penetration.

This can be best understood diagrammatically as shown below:

Butt Welding of Brass Fittings

Socket Weld

This welding design involves inserting the pipe or tubing in the recessed area of the fitting. Unlike butt weld, socket weld is used for pipe with small diameters, i.e., the diameter is equal to or small than NPS 2.

ASME B16.1 1 standards guide socket welding. It entails making a square cut on both the pipe and the fitting before installing and welding the two together.

Flanged

For this connection type, both the pipe and the fitting should have flanges. For the pipe and the fitting, the two flanges are bolted with a gasket in between to offer a seal.

For the flange connection to be leak-proof, a lot of precision has to be put in installing the gasket. The standard dimensions of flanges are contained in the ASME B16.5 guideline.

Threaded

This is probably the oldest and the most common end connection for most fittings.

Similar to socket weld connections, threaded connections are commonly used for pipes with small diameters.

There are two patterns of threads used in brass fittings:

• Tapered Threads – This type of thread has a diameter that tends to become thinner towards the end. Tapered threads comprise of British Standard Pipe Tapper Thread (BSPT), National Pipe Thread Fuel (NPTF) /National Pipe Thread (NPT), and metric tapered.
• Parallel Threads – Unlike the tapered thread’s diameter, the diameter of the parallel thread diameter is the same at both the top and the bottom. They include British Standard Pipe Parallel Thread (BSPP), UNF/UN, and metric parallel.

Also important is the pitch of these various thread types. A pitch is the number of threads per inch. Below is a table with the common pitch size for our brass fittings.

Notably, there are also female and male threads. The former has threads on the inside, while the latter has threads on the outside.

Buttress

Buttress threads are square-cut with the lines being spaced far apart, making them appear more coarse.

Thus, they are sometimes referred to as “coarse threads.”

Additionally, the structure of the buttress threads forms a hydraulic seal between the pipe or tubing and the fitting.

Spigot

Spigot connections usually function together with sockets. A socket is a fitting that goes over the pipe. On the other hand, a spigot goes into the socket.

Thus, when you plan to attach one brass fitting to another brass fitting, you are likely to use a spigot connection or end. Spigots usually act as the male ends, while sockets are the female ends.

Recommended Quality Standards for Brass Pipe Fitting

Below are the recommended quality standards that ensure the manufacturers produce quality brass fittings:

• ISO 9001:2015 – This indicates that the manufacturer is centered on meeting the customer’s requirement by regularly improving his/her products.
• DIN 2999 – It is a guideline on the structure and the design of threads used in the brass fittings.
• ASME/ANSI B16.9 – It highlights the tolerance, dimensions, ratings, markings, and testing of all brass fittings with butt weld ends.
• ASME B31.1 – It covers all the technical parameters around socket weld fittings.
• Various ASTM standards for the various brass fittings such as ASTM B687-99 (2016) for brass nipples, and ASTM B-16 for corrosion-resistant bodies.
• SAE and DOT FMVSS 571. 106 standards relevant for brass fittings.
• EN 1591 standard for various bolted fittings.

Chemical Composition of Brass Fitting

Brass is a metal alloy of zinc and copper. Copper has the most significant percentage compared to zinc.

To either make the brass fitting softer or more robust, copper is either reduced or increased, respectively. However, to improve the corrosion resistance and machinability of the brass fitting, other components, such as lead, aluminum, and arsenic, may be added.

Also, the addition of various metals to brass will help vary the color of the brass fitting. The National Sanitation Foundation International (NSF) recommends the use of red brass.

This type of brass has a zinc concentration lower than 15%. This is achieved by adding other metals to the brass, making it the strongest brass.

Brass fittings can employ the use of naval brass. It has a 40% zinc concentration with a 1% tin composition to help reduce dezincification.

For free-machining or 360 brass, it has a high lead concentration making it easy to shape and cut for fittings. However, the usage of brass with lead is not permitted in the food industry.

Thus, the usage of 360 brass is limited to non-food or non-consumption applications.

Lastly, to ensure that a brass fitting is stable in specific environments, arsenic can be added to the brass alloy. On the other hand, lead addition will work to improve the malleability of brass.

Thread Type for Brass Fitting

The two major thread types are parallel threads and tapered threads. Parallel threads have thread diameters that tend to become thinner towards the end.

On the other hand, tapered threads have thread diameter that is similar at the top and bottom. Tapered threads are classified into three; NPTF/NPT, BSPT, and metric tapered.

Parallel threads also fall under three categories; UNF/UN, BSPP, and metric parallel. Also, parallel and tapered threads can either be internal (female) or external (male).

The common pitch sizes of the various threads in our brass fittings are displayed on the table below:

Difference Between Male and Female Brass Fitting for Pipes

The major difference between a male and a female thread is in the connection type. For the male fitting, the fitting goes inside the pipe or tube.

Conversely, for the female brass fitting, the pipe goes inside the fitting. If the fitting has threads, the male fitting will have threads on the outside, while female fitting will have threads on the inside.

Taking the nut and bolt example, the male brass fitting is the bolt, whereas the female fitting is likened to the nut.

In most cases, a male fitting only connects to a female pipe or tubing and vice versa to the female fitting.

Male and Female Brass Tee Connectors

Factors to Consider when Choosing Brass Fitting for Pipes

We offer a wide variety of brass fittings for your plumbing needs. Consequently, you need to select the best brass fitting that will perform the required function and ensure value for your money.

Below are some key highlights to guide you in your selection:

Pipe End

Consider the end that your pipe has so as to know which fitting to choose. For example, it would be difficult to connect a but weld fitting to a threaded pipe.

Type of Fluid

You should gauge the corrosiveness of the fluid. If the fluid is highly corrosive, you should opt for a stronger brass fitting, i.e. one with more copper concentration or additional metals.

In a case where the fluid is used in the food industry or for consumption, the brass fitting ought to be lead-free. The fluid should also be compatible with the chemical composition of the brass fitting.

Temperature and Pressure Conditions

Although all the brass fittings are made from brass, they have different pressure and temperature ratings. This is because different types of brass are used to make the fittings.

Consequently, ensure that you check the pressure and temperature rating of a brass fitting before making the purchase.

Sizing

Sizing is an essential factor to consider. Choose the perfect fit brass fitting. As a result, you will not have to add much sealing material or worry about frequent leakages.

Budget

Similar to other commodities, brass fittings do vary in price. Consequently, choose a fitting that is within your budget.

However, don’t be a miser and go for a low-quality brass fitting, yet you can afford the quality and durable ones.

How to Measure Dimensions of Brass Fitting

Measuring the dimension of a brass fitting will help determine if the fitting will fit your pipe or tube. Lucky for you, this exercise is a walk in the park.

Below is how you can measure the diameter of a brass fitting by yourself.

For male thread/ connection:

• Lap or round a string on one end of the fitting.
• Mark the point where the string makes contact
• Move on to a ruler or tape measure and get the circumference by measuring from the tip to the marked point of contact.
• Divide the figure you obtain from the measurement by Pi (3.14159)
• Use the nominal diameter conversion chart (below) to get the size of your fitting (nominal diameter).

For Female thread/connection:

• Directly measure the inside diameter of the fitting using a tape measure or a ruler.
• Proceed to the diameter conversion chart and obtain the nominal diameter or size of the fitting.

Brass Fitting Diameter (Nominal) Conversion Chart – Measurement in Inches

Common Causes of Failure in Brass Fitting

Brass fittings may become faulty due to several reasons. Below are the common causes that might explain the failure of your brass fitting.

Dezincification

Brass comprises two major components, copper and zinc. Dezincification is the selective leaching of zinc from the brass alloy.

When it occurs, the zinc component is selectively removed from the brass fitting, leaving mainly copper. Consequently, the remaining copper (left alone with a minor zinc component) becomes weak.

Since the brass fitting now has low mechanical strength, it is now more susceptible to leakages.

Also, dezincification results in the formation of zinc oxide which is in powder form. Accumulation of the zinc oxide powder may result in blockage of the fitting or the piping system.

Stress  Corrosion Cracking

Stress Corrosion Cracking (SCC) occurs when a metal alloy is subjected to high stress in a corrosive environment. Stress can be generated from welding, cold deformation, machining, grinding, and heat treatment.

The most common brass fittings prone to this type of corrosion are those made from duplex brass. This brass has a zinc concentration within the range of 20-40%)

However, this type of cracking cannot be easily noticed since it does not damage the surface and it involves the formation of minor cracks. But, it can result in the ultimate failure of the brass fitting without much material loss.

Corrosion Fatigue Cracking

A chemical reaction can occur between the brass fitting and the fluid being passed, forming small pits. As the reaction continues, more and more pressure is applied to the pits creating fatigue.

Eventually, the pits propagate to cracks on the brass fitting.

To prevent this, you can apply a protective coating to the brass fitting. Alternatively, you can avoid using brass fittings in highly corrosive environments.

Surface Degradation

Zinc and copper oxides may form on the interface of the brass fitting. The oxides then grow through cracks to the metal surface and damage it.

This phenomenon is referred to as surface degradation. Arguably, these oxides are formed due to a lack of proper cleaning of the bath or lubricants used before electroplating the brass fitting.

Recommended Sealing to use with Brass Fitting

To ensure that a brass fitting (threaded) is leakproof, a sealant must be applied. Importantly, the sealant should be compatible with both the brass fitting and the pipe and the fluid in the system.

Commonly, two sealing materials are applied for brass fittings:

1. Tapes such as polytetrafluoroethylene (PTFE) or Teflon tape
2. Liquid or semi-liquid pastes polymerize to ensure tight sealing

Possible Causes of Leakages in Brass Fittings

Brass fittings can leak from two points; either the union or the brass fitting body.

Union

If the union is the leaking part, there is a high probability that the sealing was not tight. Consider adding an appropriate sealant if the connection is threaded.

For the other types of connections, check to ensure that you followed the correct procedure while connecting the fitting and the pipe. Also, if the brass fitting was not of the correct size, there is a high probability that the union will leak.

Brass Fitting Body

The main reason a brass fitting body will leak is due to corrosion. There four major types of corrosion a brass fitting may undergo are:

1. Dezincification
2. Stress Corrosion Cracking
3. Corrosion Fatigue Cracking
4. Surface Degradation

These types of corrosion either weaken or form cracks on the brass fitting, which results to leakage of the fitting.

Recommended Pressure Rating for Brass Fitting

The usage of brass fittings is not recommended in high-pressure conditions. This is because brass is soft and has high susceptibility to cracking, distortion, and cross-threading if overtightened or used in high-pressure conditions.

Consequently, brass fittings have a pressure rating of below 300 psi. However, depending on certain temperature conditions, the pressure rating can go up to 1000 psi.

 Yellow Brass Plumbing Fitting

Temperature Rating for Brass Fitting

The temperature rating for most brass fittings can be as low as -54^oC to a high of 121^oC.

In short, before choosing brass fittings, you should consider every aspect of this guide.

However, if you have any questions about brass fitting.

Or you’re looking for competitive prices on brass fittings, contact us now.