Since 2004, we have been specializing in custom rubber product manufacturing for five key industries – automotive, general, machine industry, mining, and oil & gas. Our experience and expertise in producing tailor-made rubber products have allowed us to cater to the unique needs and requirements of each client within these sectors.
Whether it’s rubber seals, gaskets, or other rubber components, we have the capability to deliver high-quality products that meet the industry standards. Our commitment to innovation and quality has earned us a strong reputation among our clients, and we are continuously striving to expand our product range and capabilities to better serve our customers.
Description
The Variable Bore Ram (VBR) type Pipe Ram, sized 18-3/4 inches with a working pressure of 10,000 psi, is a critical component in ram-type Blowout Preventer (BOP) systems used in oil and gas drilling operations. This VBR is specifically designed for 18-3/4 inch BOP bores and can handle high pressures up to 10,000 psi (equivalent to 69 MPa). Unlike standard pipe rams that are suitable for only one pipe size, the VBR uses elastomer elements (packing elements) with a segmented inserts or finger inserts design that can adapt to various drill string pipe diameters, typically ranging from 3-1/2 inches to 7-5/8 inches OD (outer diameter). The U-type, U-II, or TL ram block structure from manufacturers such as Cameron/Schlumberger is equipped with a top seal to prevent leaks and is designed for insert rotation when hydraulic pressure is applied, ensuring tight contact with the pipe. This component complies with API Spec 16A standards (third edition or later) and is often NACE MR0175 certified for sulfide corrosion resistance (sour service). The weight is approximately 35 kg per seal unit, making it ideal for deep well conditions or high-pressure drilling where blowout risks must be minimized.
Function
The VBR functions to close and seal the well during leaks, preventing gas explosions or high-pressure fluid blowouts. It enables effective sealing on tool joints, kelly, and other parts of the drill string without the need for frequent ram packer replacements, thereby improving operational efficiency and reducing downtime. In a 18-3/4” x 10,000 psi BOP, this ram operates at temperatures from -20°C to +120°C, suitable for extreme conditions such as high-temperature drilling. Its wide pipe range provides flexibility for various sizes of drill pipe, casing, or tubing, and it is commonly used in BOP stack configurations for well control. Advantages include reducing the need for ram changes during pipe size transitions, saving time and costs, as well as enhancing safety with consistent and reliable sealing under high pressure.
Materials
Made from durable elastomer materials such as Nitrile Rubber (NBR) and Hydrogenated Nitrile (HNBR). This component is manufactured according to the latest API 6A specifications and NACE MR0175 for corrosion resistance, with a hardness of 70-90 Shore A on the packing elements.
Applications
This VBR is widely used in oil and gas drilling operations, both onshore and offshore, particularly for well control on rigs with high-pressure and extreme temperature conditions. It is compatible with existing BOP models such as Cameron Type U or UM, often produced by companies like Cameron (now part of SLB/Schlumberger) or aftermarket suppliers, and available in complete sets with certificates of conformance (COC) valid for a certain period.