Grooved FAQs

Grooved FAQ Document August

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Q:          Is Reliable grooved compatible with other manufacturers’ grooved products?

A:           Reliable grooved products use the same AWWA C606 grooved standard common with most grooved products.  Any grooved product manufactured to this common standard should be compatible with Reliable grooved products.

Q:          Is Reliable grooved qualified on proprietary Sch 7 sprinkler pipe?

A:           Yes, we have worked with UL and FM to expand qualifications for coupling products beyond just Schedule 10 and Schedule 40 pipe to include:

• Youngstown Tube Fire-Flo
• Wheatland Tube Mega-Flow
• Bull Moose Eddyflow
• Nucor Hydroflow

Our product-specific technical bulletins contain details on pipe qualifications for every gasketed fitting. Reliable’s bulletins are constantly updated to reflect changing industry trends, evolving customer needs, and expanded 3rd party qualifications to ensure we deliver what our customers expect and need.

Q:          Are the coupling gaskets pre-lubricated?

A:           There are two types of pre-lubricated gaskets; a surface treatment applied to finished gaskets prior to coupling assembly (typically a white powder) or embedding a lubricant in the rubber mixture itself before molding so that it “blooms” out naturally. Reliable grooved couplings use both types of pre-lubrication, providing a double advantage to users of Reliable Grooved.

Q:          How do the Reliable grooved elastomer options compare to competitor products?

A:           We focus on using a standardized single elastomer type that is the most common in fire protection products, EPDM rubber. Most EPDM rubbers are very similar, and the specific chemistries provided by our manufacturing partner are fit-for-purpose for a grooved fire protection system application. The temperature range for our EPDM rubber is annotated in our product-specific technical bulletins; an end-user should evaluate the specific requirements of their application and municipality regulations to determine if our UL / FM qualified temperature range is appropriate. All gaskets are qualified by UL and FM just like our competitor’s products, so you can be assured that our grooved products will perform the same.

Q:          Are the takeout dimensions of grooved fittings and couplings the same as other grooved manufacturers?

A:           Some products (depending on the model number and NPS) use identical takeout dimensions, while others are slightly different. Most of the takeout dimensions that are not identical across the various brands are close enough that they should not impact installation; however, a qualified and experienced installer should review the takeout dimensions and assess any compatibility issues with Reliable grooved products.

Q:          Can I use two halves of a mechanical tee to make a mechanical cross?

A:           FM and UL require specific qualifications to utilize these products in this way; at this time, RASCO is not qualified for this configuration. While the products are physically capable of being assembled in this configuration due to the design of cast components, they lack FM and UL qualification in this configuration should be considered against industry and municipality requirements before installing in this configuration; and is not recommended.

Q:          Are u-bolt mechanical tees approved for use on branch lines, or just sprigs and drops?

A:           This is a complicated question to answer. FM allows the use of u-bolt mechanical tees with 1” outlets for connecting branch lines, but UL requires additional testing that has not been performed for Reliable u-bolt mechanical tees. If an installer wishes to use a u-bolt mechanical tee with a 1” outlet to connect a branch line, the lack of UL-qualification in this application should be considered by a competent technical authority. Reliable’s recommendation is that a conventional mechanical tee (MTT2 or MTG1) be used for branch line connections, as these products in all sizes are qualified for this type of use.

Q: My 1-1/4” x 1-1/2” RCD Reducing Couplings do not have a metal ring.  Is this a problem?

A:  Most sizes of RCD Reducing Couplings use a metal reinforcing ring to provide additional support to the gasket that allows it to resist pressure and maintain a seal.  The need for this reinforcing ring is dependent on the size difference between the two sides of the reducing coupling.  For the 1-1/4” x 1-1/2” size, the outlets are so close in size that a metal reinforcing ring is not necessary, and all UL / FM qualification testing has been performed without one.  The product is fit-for-purpose without the metal ring and can be installed just like any other grooved coupling.

Q:          I’m having difficulties with Reliable grooved installation; what do I do?

As an advanced pipeline connection method, the grooved pipe fitting connection can be either exposed or buried. There are steel joints and flexible joints. Therefore, it has a wide range of applications. 

Table of contents

• What are grooved pipe fittings

• Types of grooved fittings

• Apron difference of grooved pipe fittings

• Where to go to import grooved pipe fittings

What are grooved pipe fittings

Before the appearance of grooved couplings, the flexible couplings of metal pipes experienced coupling methods such as welding, threaded couplings, and flanged couplings. Grooved pipe fittings are quick and convenient to install, so they are widely used. Before installing the grooved pipe fittings, it is necessary to use a professional rolling groove machine to make grooves at the pipe ports, and then use a clamp to connect the two ports with grooves. Of course, roll grooving is only performed at the ends of straight pipes. For pipe joints such as elbows, tees, and crosses, grooves have been made during casting. Therefore, grooved products can also be divided into grooved connectors, that is, clamps and grooved pipe fittings. 

Grooved Coupling

Grooved pipe fittings

Types of grooved fittings

Grooved pipe fittings are mainly divided into the following categories:

Elbow categories: including 90° elbow, 45° elbow, 22.5° elbow, 11.25° elbow and other angle elbows;

XGQT03 90°ElbowXGQT04 45° ElbowXGQT05 22.5° ElbowXGQT06 11.25° Elbow

Tee type: including regular tee, groove reducing tee, thread reducing tee, medium and large tee, etc.;

For more Grooved Pipe Fittingsinformation, please contact us. We will provide professional answers.

XGQT07 Equal TeeXGQT08 Grooved Tee ReducingXGQT08S Threaded Reducing TeeXGQT17 Mechanical TeeXGQT17S Threaded Mechanical Tee

Four-way type: including positive cross, groove reducing cross, thread reducing cross, etc.;

XGQT09 Equal CrossXGQT10 Grooved Cross ReducingXGQT10S Threaded Reducing CrossXGQT15 Mechanical CrossXGQT15S Threaded Mechanical Cross

Mechanical tee: including grooved mechanical tee, threaded mechanical tee, grooved mechanical tee, wire-connected mechanical tee, machine three lower piece, U-shaped wire-connected mechanical tee, etc.;

XGQT17 Mechanical TeeXGQT17S Threaded Mechanical TeeXGQT15 Mechanical CrossXGQT15S Threaded Mechanical Cross

Reducer: including groove concentric, thread concentric, groove eccentric thread eccentric, etc.;

XGQT11 Reducer ConcentricXGQT11S Threaded Reducer ConcentricXGQT12 Grooved Eccentric Reducer

Flanges: including single-piece flanges (also called flange pipe clips, split flanges, flange sheets, etc.), short-pipe flanges (also called conversion flanges, grooved short pipes, high-neck flanges, etc.);

XGQT13 Flange AdaptorXGQT14 Grooved Flange

Pipe plugs: including blind sheets (also called pipe plugs, blind plates, etc.).

XGQT16 Grooved End Cap

Grooved pipe joints: mainly rigid pipe joints, flexible pipe joints, etc.

XGQT01 Grooved Rigid CouplingXGQT02 Grooved Flexible Coupling

Apron difference of grooved pipe fittings

The sealing ring used in the grooved pipe joint realizes the sealing performance of the system by increasing the pressure. From the perspective of cross section, it belongs to "C" type design. The higher the pressure, the better the sealing performance. The material used for the sealing ring can be determined according to the medium conveyed by the pipeline, and different materials have different letter codes on the sealing ring. For example, EPDM rubber (code E, black) is usually used in fire protection systems; silicone rubber for drinking water (code S, pressure cooker seal material, milky white); nitrile rubber (code D, orange); natural rubber (code N, black). Therefore, in fire engineering, black EPDM rings must be used.

Fire fittings with black EPDM seals

Where to go to import grooved pipe fittings

First, you need to confirm which country you are importing from. The question is simple, China is the best choice. Although the manufacturing history of grooved pipe fittings in China is not long, the manufacturing industry of grooved pipe fittings has developed rapidly in China and has formed a complete manufacturing industry chain. Grooved pipe fittings imported from China are of good quality on the one hand and relatively cheap on the other hand. After determining the importing country, which company should import grooved pipe fittings from?

I would like you to recommend Hebei Jianzhi Group. Jianzhi Group was founded in and is considered a very old enterprise in China. Jianzhi Group has full-process grooved pipe fittings casting capabilities. In summary, Jianzhi Group has the following advantages:

1. Good quality

a. Excellent quality

Compared with the national standard products, the quality of Jianzhi products is the heaviest, obviously heavier than the national standard products of any manufacturer in China.

b. beautiful appearance

Due to years of molding casting experience and leading technical advantages, Jianzhi products have the best appearance finish in China. Because the molding sand is fine and dense, there are no traces of large sunken sand holes on the surface.

c. Most accurate thread

As mentioned in the thread process above, the pipe thread standard for construction is the most stringent in the industry, and the length and precision of pipe threads are strictly implemented in accordance with national standards. The installation is simple and trouble-free, and the sealing performance is good.

2. The types and specifications of malleable grooved pipe fittings are complete. 

We have a good cooperative relationship with many brother factories that produce stainless steel pipe fittings and valves, which can fully meet the needs of customers for one-stop procurement.

3. Sufficient production capacity and stable supply.

The annual production capacity of Jianzhi Group has reached 400,000 tons, and it is the only company in China that can still produce at full capacity without being affected by the national environmental protection policy. Therefore, the products of Jianzhi Group can provide customers with a guaranteed production cycle and delivery cycle, so that customers can avoid the pain of shortage.

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For more information, please visit Grooved concentric reducer.