Stainless Steel Long Pattern Stub Ends Butt Weld ASME B16.9 Fittings

Stainless Steel Long Pattern Stub Ends Butt Weld ASME B16.9 Fittings

1.Product Description

Stainless Steel Stub Ends are pipe termination components specifically designed for rapid on-site assembly and convenient future maintenance. Consisting of a short pipe body with a flared lap end, they form a "detachable, rotatable, and replaceable" flange connection pair when matched with Lap Joint Flanges. The product leaves the factory with the lap already formed, solution-annealed, and the sealing face precision-finished. On-site, only a single butt weld is required to integrate it with the piping system. Compared to traditional weld neck flanges, it significantly reduces the on-site difficulty of precise cutting, beveling, and high-altitude alignment welding for large-bore pipes, making it particularly suitable for tight-schedule projects, confined installation spaces, or applications with frequent future overhauls.

2.Product Applications

This product is specifically suited for the following four typical engineering scenarios:

1. High-Altitude and Confined-Space Operations: In pipe rack upper levels or equipment mezzanines where hoisting is difficult, only the lightweight flange ring needs to be slipped over the stub end and bolted. No heavy integral flange lifting is required, significantly reducing safety risks associated with working at height.

2. Frequent Opening/Cleaning of Strainers and Heat Exchangers: In chemical plant pre-pump strainers and heat exchanger channel connections, this product enables quick disassembly, meeting operational needs for regular removal of coked deposits or replacement of filter elements.

3. Flexible Transition Sections at Pipe Rack Ends and Equipment Nozzles: Used for connecting large compressor and turbine inlet/outlet lines. The slight clearance of the lap joint flange absorbs minor vibrational displacement during equipment operation, preventing interface damage caused by rigid connections.

4. Rapid Assembly of Temporary Piping and Commissioning Lines: During project commissioning phases, frequently altered temporary lines can be quickly assembled and dismantled using stub ends and lap joint flanges. The fittings can be reused across multiple locations, reducing one-time capital expenditure.

​3.Product Advantages

4.Product Functions

1. On-Site Fit-up Tolerance and Fine-Tuning Function: The straight pipe section of the stub end has a certain length allowance. On-site fit-up allows slight trimming to absorb accumulated length errors from pipe prefabrication, ensuring stress-free alignment between the flange face and the equipment nozzle.

2. Uniform Bolting Force Transmission and Cushioning Function: The curved transition surface at the back of the lap evenly distributes bolt pre-tension across the entire sealing circumference, preventing local over-compression and gasket collapse. Meanwhile, the fit clearance between the back shoulder and the flange bore provides micro-cushioning, reducing the direct impact of shock loads on the weld.

3. On-Line Inspection Window Function for the Piping System: After disconnecting the lap joint flange, the interior of the stub end and the pipe wall can be directly exposed for inspection. This serves as a temporary inspection port, allowing borescope examination of internal corrosion or scaling conditions.

4. Rapid Piping Isolation and Blind Plate Insertion Function: When temporary isolation of a pipe section is required, a paddle blind can be inserted directly between the stub end lap face and the lap joint flange, achieving rapid process isolation without additional pipe cutting.

FAQ

1. Are you trading company or manufacturer ? We are manufacturer ,You can see the certification.

2.How long is your delivery time? Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.

3. Do you provide samples ? is it free or extra ? Yes, we could offer the sample for free charge but need pay the cost of freight.

4. What is your terms of payment ? Payment<=1000USD, 100% in advance. Payment>=1000USD, 50% T/T in advance ,balance before shippment.