Lap Joint Flange


A stainless steel lap joint flange is a flange that consists of two parts, a stub end and the backing flange. On a Lap Joint, the flange slides over the pipe and the stub end is the connection where the gasket sits. The end where the gasket sits is the same outside diameter as the face of a raised face flange. In general, the thickness of the hub is between ¼” to 3/8”. Using lap joint flanges might be an option for saving costs when the piping is made of exotic materials. By using ANSI B16.5 lap joint flange, the wet materials would consist of the exotic materials and the flange would be carbon steel. The abbreviation of lap joint is LJ Flange which have implementation in industries that uses piping.

One can also rotate the flange which can be useful while fixing issues with bolt hole alignment. Since the flange doesn’t ever come in contact with the process fluid, it would not be affected by the fluids. When designing a piping system, lap joint flange should not be considered solely to alleviate poor alignment during construction. Good design practice should not need to include poor construction quality. However, if the piping needs to be frequently dismantled for inspection or cleaning, consideration should be made for lap joint flanges. They give the ability to swivel flanges and to align bolt holes which simplifies the assembly of large diameter or unusually stiff piping.

What are the uses of Lap Joint Flanges ?

Lap joint flange are usually used in low pressure applications and are not suitable when there are high loads on the flange pair. Some types of piping require the use of lap joint flanges. For example, metallic pipe that has been plastic lining may have lap joint flanges.

Using lap joint flanges might be an option for saving costs when the piping is made of exotic materials. By using a lap joint flange, the wetted materials would consist of the exotic materials and the flange would be carbon steel. Since the flange doesn’t ever come in contact with the process fluid, it would not be affected by the fluids.

Dimensions on the lap joint flange are similar to weld neck, slip on or socket weld flanges. The backing flange has the same number of bolt holes, size and thickness of a weld neck or slip on flange.

The lap joint flange is practically identical to a slip-on flange except it has a radius at the intersection of the bore and flange face. The lap joint flange is practically identical to a slip-on flange except it has a radius at the intersection of the bore and flange face. This radius is necessary to have the flange accommodate a lap joint stub end. Normally, a lap joint flange and a lap joint stub end are mated together is an assembly system.

ASME / ANSI B16.5 Lap Joint Flange Manufacturer In India

Devdeep Steel Alloys is a specialised manufacturers of high quality pipe Lap Joint flange available in standards ANSI B16.5 Flanges, ANSI B16.47 Series A & B, DIN Flange, JIS B2220 flange, MSS SP44 Flange, EN1092-1 FLANGES, API 605, AWWA C207 Flange, industrial pipe flanges in India. We quickly provide the standard size of stainless steel flanges and carbon steel flanges because of ready stock facility. ANSI B16.5 Lap Joint Steel flange have generally pressure ratings as follows. 150 lb, 300 lb, 400 lb, 600 lb, 900 lb, 1500 lb, 2500 lb. We also manufacture plate Lap Joint flanges from special nickel alloy steel grades. The material is provided within few working days in time programs.

Our Lap Joint pipe flange are available with face type of Flat Face (LJFF), Raised Face (LJRF) & Ring Type Joint (SORTJ) and also with male threads. Steel Lap Joint flanges are also available with or without hub as per the requirement of customer. Devdeep Steel Alloys offer steel plate flanges to all companies coupled with various industries. For instance petrochemical plants, paper mills, power generation, pharmaceutical plants, oil refineries, shipbuilding, turnkey projects and waste water treatment plants among others.

Lap Joint pipe flanges are comparatively used where high & huge pressure applications are needed. To allow an easy access, in a piping system you should use Lap Joint steel flanges only one time when it is closed. At the present time we design Lap Joint flange with advance technology made from raw material of high quality, that have low maintenance. Moreover the products are available at very fair & competitive price.

Types Of Pipe Flange

Slip-on flange, weld neck flange, threaded flange, socket weld flange, blind flange, lap joint flange are the most common types of steel flanges. The special flanges such as orifice flanges, long weld neck flanges, spectacle flange to cater all industrial needs. In fact steel pipe flange are manufactured according to international quality standards which are available in various material, sizes & dimensions. In hazardous welding areas where the situation is extraordinary and areas are highly volatile. For that reason one can use our pipe flanges as an advantage in working those circumstances. Thereupon we timely deliver the products within stipulated time frame. High durability, corrosion resistance technique as well as dimensional accuracy are the advantages of our products. Our range of flanges consequently got approval in the global and the domestic markets

Carbon Steel / Stainless Steel Lap Joint Forged Flanges Production Range

Size: 1/2″ (15 NB) to 48″ (1200NB)

Standards: ANSI B16.5 Flanges, ANSI B16.47 Series A & B, DIN Flange, JIS B2220 flange, MSS SP44 Flange, EN1092-1 FLANGES, ASA, API 605, AWWA C207 Flange.

Pressure Ratings: Class 150, Class 300, Class 400, Class 600, Class 900, Class 1500, Class 2500. PN6, PN10, PN16, PN25, PN40, PN64 etc.

Carbon Steel Lap Joint Flanges: A350 LF1, LF2, LF3 CL1/CL2.

A694 F42, F46, F48, F50, F52, F56, F60, F65, F70, A516.60, 65, 70. Steel RST37.2, C22.8

Stainless Steel Lap Joint Flanges: ASTM A182 F202, F304/304L/304H, F316/316L, F316H, F316TI, F310, F321, F904L.

Alloy Steel Lap Joint Flanges: ASTM A182 F1, F5, F9, F11, F22, F91.

Nickel Alloy Lap Joint Flanges : Alloy C22, C276, A400, A600, A625, A800 & A825 / ASTM B462 Alloy 20.

Flange Face Type: Flat Face Flanges (FF), Raised Face Flange (RF), Groove and Tongue, Ring Type Joint (RTJ)

Coating/Surface Treatment: Oil Black Paint, Anti-rust Paint, Yellow Transparent, Cold and Hot Dip Galvanised, Zinc Plated.

Value Added Services: Customised Flanges & CNC Machining.

DIMENSIONAL TOLERANCES OF LAP JOINT FLANGES

Ansi B16.5 lap joint flange dimension

OUTSIDE DIAMETER  ≤ 24 = 1.6 mm > 24 = ± 3.2 mm
INSIDE DIAMETER≤ 10 = ± 0.8 mm ≥ 12 = + 1.6 mm / – 0 mm
OUTSIDE DIAMETER OF HUB ≤ 12 = + 2.4 mm / – 1.6 mm ≥ 14 = ± 3.2 mm
DIAMETER OF COUNTERBORE : Same as for Inside Diameter
DRILLING  Bolt Circle = 1.6 mm Bolt Hole Spacing = ± 0.8 mm
ECCENTRICITY OF BOLT CIRCLE ≤ 2½ = 0.8 mm max. ≥ 3 = 1.6 mm max.
THICKNESS ≤ 18 = + 3.2 mm / – 0 ≥ 20 = + 4.8 mm / – 0
LENGTH THRU HUB ≤ 18 = + 3.2 mm / – 0.8 mm ≥ 20 = + 4.8 mm / – 1.6 mm
DIAMETER OF CONTACT FACE 1.6 mm Raised Face = ± 0.8 mm 6.35 mm Raised Face, Tongue & Groove / Male-Female = ± 0.4 mm

ANSI B16.5 Lap Joint PIPE FLANGE SIZES – 1/2″ THROUGH 24″ LJRF / LJFF

Lap Joint Raised Face Flange

  • ANSI Class 150, B16.5 (in)
  • ANSI Class 300, B16.5 (in)
  • ANSI Class 400, B16.5 (in)
  • ANSI Class 600, B16.5 (in)
  • ANSI Class 900, B16.5 (in)
  • ANSI Class 1500, B16.5 (in)
  • ANSI Class 2500, B16.5 (in)

Marking & Packaging

Steel Flange Marking & Packaging

We deliver Lap Joint flange from our warehouse to your workplace with complete protection in the meantime. The unforeseen accidents can damage the product during delivery, therefore we pack them in wooden pallet. In case of exports, we use wooden cases for standard export packaging. We take great care of product during transportation and operation. To clarify details, we clearly label the products regarding quality, quantity and product I.D outside the package. To prevent damage during transportation, Devdeep cover the product in plastic bags and close them in cartoon boxes. Furthermore we also provide seaworthy wooden cases plywood boxes according to the requirement of customer.

The Lap Joint, LJ Flanges contains marking such as Lot no, Steel Grade, outside diameter, Size & dimension, Wall thickness including Devdeep Steel Alloys Brand Mark. For customised marking you can contact us. We guarantee the fastest delivery for products in country, because of well equipped storage and warehouse facilities.

Quality Assurance & Test Certificates:

We undertake strict inspection at each stage in the process of production of Lap Joint flanges. At Devdeep Steel Alloys from purchasing of material to dispatch the product contains no defect. Our team member frequently examine the flange to confirm the international quality, codes and standards. ASTM, ASME (American), MSS, DIN German), EN (European), JIS (Japanese). To confirm the quality of products, to witness the dimension & material reports. We can call a certified Third Party Inspection agencies upon request. At Devdeep Steel Alloys, the clients can nominate Third Party Inspection for offered products. We can also arrange the TPI by World reputed Agencies like LLOYDS, DNV, ICB, Bureau Veritas and many other.

We use high quality raw material for manufacturing steel Lap Joint flange tested from approved NABL Lab. Other testing reports such as Non Destructive or destructive and Hydro Testing Reports can be provided upon request of customer,

Manufacturer Test Certificate (MTC) as per EN 10204 / 3.1B will be provided along with the ANSI B16.5 Lap Joint Flanges. In addition 100% Radiography Test Report, Raw Materials Certificate & Third Party Inspection Report available on demand.