Ball Valves
Ball valves use a ball with a cylindrical bore as the closing member: rotating the ball 90° around the stem axis fully opens or closes the valve. Low flow resistance, fast operation and reliable sealing make them one of the most widely used isolation valves in oil & gas, refining, petrochemical and long-distance pipeline service. The range is divided into floating ball and trunnion-mounted designs. Floating ball valves are compact and cost-effective for low-to-medium pressure and small-to-medium sizes. Trunnion-mounted valves support the ball at both the stem and the bottom trunnion, so media thrust is not carried by the seat, giving low operating torque and high pressure capability, and enabling double block and bleed (DBB) and double isolation and bleed (DIB). They are the preferred design for high-pressure, large-diameter and pigging duty on long-distance pipelines. Pressure ratings cover ASME B16.34 Class 150–900 (PN 20–PN 150), with high-pressure versions extending to Class 1500/2500. Body materials include carbon steel WCB, low-temperature steel LCB/LCC, stainless steel CF8/CF8M, duplex 2205/2507 and nickel-based alloys. Sealing is PTFE/RPTFE/PEEK soft seat or 13Cr/Stellite metal seat to suit the duty. Design and manufacture follow API 6D, API 608 and ASME B16.34, with fire-safe and anti-static designs to API 607/6FA and API 608; supporting certificates can be supplied on request.
Trunnion-Mounted Ball Valve
Trunnion-mounted ball valves support the ball at both the stem and a bottom trunnion. Line thrust is carried by the trunnion and bearings instead of being transferred to the seats, so operating torque is low, pressure capability is high and large sizes are feasible. This is the mainstream construction for high-pressure, large-diameter pipeline ball valves. The design is full bore with bidirectional sealing and supports double block and bleed (DBB) and double isolation and bleed (DIB). Fire-safe (API 607/6FA) and anti-static (API 6D) features are provided, and the seats accept sealant injection for emergency sealing. End connections are flanged, butt-weld or fully welded; applications include oil and gas transmission pipelines, gathering stations and pigging operations.
Threaded Ball Valve
Threaded ball valves use NPT or BSP tapered pipe threads, eliminating flanges and gaskets. They are compact and low-cost, and are the most widely used ball valve type in threaded piping systems. The valve uses a one-piece or two-piece body with a floating ball and full bore, sealed by soft seats. Threads are machined to ASME B1.20.1 (NPT) or ISO 228 (BSP). Note that NPT and BSP threads differ in thread form and taper and are not interchangeable; the thread standard should be stated clearly in the enquiry.
Three-Piece Ball Valve
Three-piece ball valves consist of a central body and two end connectors clamped together by long bolts. Removing the centre section gives access to the ball and seats, so internal parts can be serviced or replaced without dismantling the pipeline — the most maintenance-friendly ball valve configuration. The body is usually investment-cast or bar-stock stainless steel, with threaded or butt-weld ends, a full bore and PTFE soft seats. The top of the body carries an ISO 5211 mounting pad for direct mounting of pneumatic or electric actuators for automated control.
Wafer Floating Ball Valve (Thin Type)
Wafer ball valves use a thin body clamped between the flanges at both pipe ends by through-bolts. The body is substantially thinner than a conventional flanged ball valve, making the design suitable for piping with restricted installation space. The construction is floating ball with full bore: the ball is held by the soft seats and rotated 90° for opening and closing. Because the body has no integral flanges, it is clamped by the pipe flanges during installation. The valve is normally used for small and medium sizes at low to medium pressure in water, oil and compressed air lines, allowing compact layouts in confined spaces.
Flanged Floating Ball Valve (Full Port)
Flanged ball valves use a two-piece or one-piece body with a floating ball: line pressure presses the ball against the downstream soft seat to achieve shutoff. The full-bore design keeps the bore identical to the pipe inside diameter, minimizing pressure loss and allowing pig passage. The body ends are standard flanges to ASME B16.5, simplifying installation and maintenance. The stem uses an anti-blowout design with an anti-static device, and the soft seat retains a degree of metal secondary sealing after fire exposure. The valve is suited to shutoff and isolation of water, oil, natural gas and mildly corrosive media in petrochemical, power generation, water treatment and general industrial piping.