Lap Joint Flanges

Made in China Lap Joint Flanges. We can produce flanges to ASME standards, as well as flanges that meet other standards. You can also provide drawings and let us produce custom flange products.

China Lap Joint Flanges

We provide flange products of various standards, such as ASME/ANSI B16.5, EN standards, etc. We also provide customized Lap Joint flange products.

As a company with 25 years of flange production experience, we support all types of flanges, and we can give you the best product quality, the most reasonable price.

Luis Liu

lewis Liu

Sales Manager

What is Lap Joint Flanges

A lap joint flange is a flange that is loosely attached to the flange of a container or pipe. ‌‌It is characterized by being movable on the pipe end. The flange is usually placed at the end of the pipe using a flange, a steel ring, etc., and the flange can be movable on the pipe end.

This design prevents the flange from generating additional torque on the container or pipe when deformed. It is also easy to manufacture and can be made of materials different from those of the container or pipe, thereby saving precious metals. The flange of a lap joint flange can be made by flanging, direct turning, or welding a ring.

Its advantages include not generating additional torque on the container or pipe, being easy to manufacture, and being able to be made of different materials. However, the disadvantage of a lap joint is that the flange is relatively thick and is suitable for occasions where the container or pipe is lined with brittle materials and the pressure is not high.

Lap Joint Flanges Product Image Gallery

Here are various Lap Joint Flanges produced by YANHAO. You can click on the pictures to enlarge them. As a company with 25 years of flange production experience, YANHAO supports all types of flange production.

Standardized Lap Joint Flanges

  • Lap Joint Flanges are commonly standardized as ASME B16.5 and ASME B16.47, with sizes ranging from 1/2 inch to 60 inch.
  • Sealing surface types include raised face (RF), flat face (FF), dimpled face (MFM), tongue and groove (TG), ring joint (RJ), and so on.
  • Applicable pressure classes include Class 150, 300, 400, 600, 900, 1500, 2500.
ASME B16.5 Lap Joint Flanges
Class 150Class 900
Class 300Class 1500
Class 400Class 2500
Class 600

Customized Lap Joint Flanges

The following options are for you to customize. If you don’t have a design drawing, you can also consult our engineers and let us help you draw it.

size

Specified pipeline size, including flange ID and OD, thickness, bolt hole diameter, bolt hole distance, etc.

Material

Using specified material suitable for pipeline engineering according to your requirements.

Shape

can be customized with irregular flanges such as square flanges, and conical flanges, etc.

Connection

Threaded connection, welding connection, socket welding connection, etc., which can be selected.

Special Treatment

Special treatments such as surface coatings, anti-corrosion can be made according to your needs.

The customization process for flanges is generally as follows:

1

requirements
Confirmation

Communicate in detail to determine the requirements for flange size, material, pressure, connection method, etc.

2

Design drawings

Our professional engineers will design flange drawings for you. The drawings will specify the size, shape, thickness, etc. of the flange in detail.

3

Choose materials

Select suitable flange materials according to the requirements of the engineering project.

4

Customer confirmation

Send detailed information such as the designed drawings and materials to the customer for confirmation.

5

Processing sample

To ensure accuracy, first produce a sample according to the drawings and selected materials and send it to the customer for trial confirmation.

6

Production of bulk goods

After confirming the accuracy of the samples, proceed with mass production.

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About YANHAO

Aerial view of YANHAO Factory
Aerial view of YANHAO Factory

YANHAO is a flange manufacturer located in Hebei Province, China. It is one of the few professional flange suppliers in China.

We have many years of experience in flange production and have multiple flange production lines. We have sufficient stock of raw materials, rich inventory, fast delivery, and can ship within three days. At the same time, the price is affordable. You are welcome to consult and purchase!

In addition, we can provide a variety of bespoke flanges and pipe fittings. Customers can give drawings or samples, and our company will produce them to fit your specific requirements.

Learn more about YANHAO >>

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specifications & characteristics of Lap Joint Flanges

This table provides a comprehensive overview of Lap Joint Flanges, covering key specifications, characteristics, and additional considerations. Specific details and requirements may vary based on the chosen flange size, pressure rating, and material.

Specification/FeatureDescription
StandardASME/ANSI B16.5 Lap Joint Flange.
TypeLap Joint Flange – A type of flange consisting of two parts: a stub end and a backing flange. The stub end is butt-welded to the pipe, while the backing flange allows easy bolt-on connection.
Pressure RatingsAvailable in different pressure classes, such as 150, 300, 600, 900, 1500, 2500, etc., to accommodate varying pressure requirements.
Size RangeTypically available in sizes ranging from 1/2 inches to 48 inches or larger, suitable for various pipe and equipment sizes.
MaterialsASME/ANSI B16.5 Lap Joint Flanges can be manufactured from materials like carbon steel, stainless steel, alloy steel, and more, chosen based on application requirements.
Facing TypesCommon facing types include Raised Face (RF), Flat Face (FF), Ring-Type Joint (RTJ), and Male and Female (M&F) facings, impacting sealing methods.
Bolt Hole Quantity and DiameterThe number and diameter of bolt holes vary with flange size and pressure rating, facilitating flange connection.
Connection MethodASME/ANSI B16.5 Lap Joint Flanges consist of two parts: a stub end that is butt-welded to the pipe, and a backing flange that is bolted to the stub end, allowing for easy disassembly and alignment.
Application AreasLap Joint Flanges are used in industries where easy alignment and disassembly are required, such as in systems with frequent maintenance needs.
Standards and CodesASME/ANSI B16.5 Lap Joint Flanges adhere to standards set by the American National Standards Institute (ANSI) and nominal pipe size (NPS) standards, such as ANSI B16.5.
Seal TypesLap Joint Flanges commonly use gaskets or O-rings for sealing, with the choice of seal type depending on the application and pressure rating.
Accessories and AttachmentsSome applications may require additional components such as flange gaskets, bolts, nuts, and flange cover gaskets.
Inspection and TestingASME/ANSI B16.5 Lap Joint Flanges typically undergo a series of inspections and tests to ensure they meet quality and performance requirements, in compliance with standards.
Marking and CertificationLap Joint Flanges should be marked with the manufacturer’s identification, size, class, material, and other relevant information. Some flanges may require specific certifications such as PED or ASME.
Installation and MaintenanceProper installation and regular maintenance of Lap Joint Flanges, including weld integrity, bolt torque, flange face cleaning, and seal replacement, are crucial for system integrity and performance.
Application StandardsIn specific industries and applications, there may be industry-specific Lap Joint Flange application standards that need to be adhered to for safety and performance.
ASME/ANSI B16.5 Lap Joint Flanges Main Features and Specifications Table

FAQs About Lap Joint Flange

ASME B16. 5 Lap Joint Flanges are mostly used with stub end fittings. This is usually welded and is free to rotate around the stub end. This consists of various dimensions and it includes factors like nominal size, outside diameter, thickness, and many more.

Freedom to swivel around the pipe facilitates the lining up of opposing flange bolt holes. Lack of contact with the fluid in the pipe often permits the use of inexpensive carbon steel flanges with the corrosion-resistant pipe.

5 are. Welding Neck, Slip On, Socket Weld, Lap Joint, Threaded and Blind flange. Below you will find a short description and definition of each type, complete with a detailed image.

Lap joint flanges are extremely similar to slip-on flanges, with the primary difference being that the bore and face have a curved radius to accommodate a lap joint stub-end. Lap joint flanges and stub-end assemblies are commonly employed in circumstances where regular disassembly for inspection is necessary.

The flanged joint design means that pipes are secured by external screws, providing additional joint support for the transportation of substances at high pressure.

To assemble a lap joint ring flange and stub end, the stub end must slide into the bore of the flange ring and then be butt welded to the pipe. One side of the stub end forms the sealing face, whilst the opposite/back side of the stub end presses against the lap joint flange ring (when the flange is assembled).