Twin Screw Pump (Series D2S)

The Twin Screw Pump, part of Delta PD Pumps' Series D2S, operates on a unique principle that offers versatility in operating parameters, ensuring total reliability and maintenance-free service. It features a pair of specially profiled screws, machined from solid stock and supported on antifriction bearings within precision-bored interchangeable casing liners. Each screw set comprises one right-hand and one left-hand screw engaging with a similar but opposite hand screw pair. Hardened and profile-ground timing gears synchronize the screws, maintaining a small but positive clearance between the flanks, thus preventing metal-to-metal contact. This design allows the pump to run dry temporarily without damage, handle fluids with low lubricating value, and manage a wide range of viscosities. The absence of metal-to-metal contact reduces wear and tear, ensuring an extended service life. The pump's design results in low internal velocities, leading to minimal NPSHR even at high speeds and while handling viscous products. Opposed screw pitches eliminate axial thrusts, and the relatively small screw diameters enable high-speed operation directly coupled to prime movers without speed reducers. The axial flow without turbulence ensures gentle handling of products, with low noise and vibration levels. The positive clearance between running parts allows construction in various materials, including stainless steel, without the risk of seizing. Typical applications include loading and unloading of fuel oil and other products from railway wagon rakes, truck tankers, barges, ships, and tankers; bulk cargo handling; lubrication, circulation, and cooling; process pumping of high-viscosity products like bitumen, molasses, and soap; and long-distance pipeline pumping of viscous products.