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A piston vacuum pump is a type of pump that utilizes a unique piston mechanism to create a vacuum. WOB-L® pumps are fully accessorized, robust, oil-free piston pumps designed for standard-duty applications where corrosion resistance is not required, such as filtration, gas sampling, vacuum drying, or automation technology. With flow rates ranging from 0.66 to 12.06 m3/h and ultimate vacuum capabilities from 292 to 6 mbar, WOB-L® piston vacuum pumps excel in speed, ease of use, and durability, ensuring high efficiency and performance. Welch’s offering includes single-head and twin-head piston vacuum pumps, OEM, and built-in pumps, as well as a broad selection of vacuum pump accessories.
A piston vacuum pump is a specialized type of pump that operates using a unique piston mechanism to create a vacuum. This mechanism involves the movement of a piston within a cylinder to generate a low-pressure environment by removing air or gas molecules from a confined space. As the piston moves, it creates suction that draws in the surrounding air or gas, effectively creating a vacuum within the system. This technology is widely used in various applications, ranging from industrial processes to laboratory experiments, where the creation of a controlled vacuum environment is essential for specific tasks.
Piston pumps are reliable, dry vacuum/pressure pumps suited for a wide array of physical and aqueous vapor applications. Designed without the need for corrosion resistance (please note their unsuitability for pumping acidic, basic, or organic fumes), these oil-free vacuum pumps are recommended in a wide range of standard duty applications in both laboratory and industry, including:
Piston pumps remain one of the most popular and most widely used vacuum technologies. Welch’s WOB-L® dry piston vacuum pumps provide you with several benefits to help you improve and streamline your mission-critical vacuum processes. They include:
Welch offers a diverse portfolio of WOB-L® piston pumps to meet various needs and applications. Choose from:
Single Stage Vacuum & Pressure Stations:
Dual Stage Vacuum Pumps with Catch-Pot and Regulator:
Single Stage Vacuum Pumps with Catch-Pot and Regulator:
Oil-free piston pumps offer a host of advantages for your operations:
The operation of piston vacuum pumps revolves around a set of key components: an electric motor, a crankshaft, a connecting rod, and a piston enclosed within a cylinder. This mechanism functions based on the principle of positive displacement. The pump's motor imparts rotational energy to the crankshaft, initiating its rotation. Subsequently, the connecting rod converts this rotary motion into the reciprocal motion of the piston.
Within the cylinder, as the piston moves alternately up and down, a vacuum is created during its downward stroke. This action prompts the medium to be drawn into the cylinder chamber via an open inlet valve. Depending on the design, single or multiple cylinders may be linked to the motor. In the latter configuration, the pump's capability is amplified, whether in terms of flow (in a parallel setup) or vacuum (in a two-stage configuration).
A distinctive feature of WOB-L® vacuum pumps is the direct connection between the piston and the rod. Unlike conventional designs, there is no intervening wrist pin; the two components form a single unit. This direct coupling results in a characteristic wobbling motion of the piston. Guided within a flanged polymer cup, the piston moves within the cylinder bore, creating a seal against the cylinder wall.
As the piston moves, air pressure expands the cup against the cylinder wall, compensating for its wobbling action. This innovative design ensures exceptional vacuum capabilities relative to the pump's compact size and lightweight construction. Additionally, it maintains consistent moderate-to-high flows, contributing to sustained performance throughout the product's lifespan.
About Welch Vacuum
Welch is a recognized provider of vacuum pumps, systems, and fittings for industrial, life sciences, and laboratory applications. We design, manufacture, and deliver products meeting the strictest requirements for mission-critical applications, and provide a comprehensive offering of products and great engineering capabilities to fit our customers’ needs.
As a reliable and trusted partner for OEMs, we stand up to the challenge of supplying best-in-class products and solutions on time to manufacturers of equipment in the life sciences, healthcare, and industrial segments.