Hydraulic hand pumps are often used for pressurizing a hydraulic system when electrical or mechanical power is not available. In addition to supplying standby or emergency power, they are also used as a primary pump for hydrostatic testing and for extending cylinders in outrigger assemblies, which are widely used on construction equipment.
Designers of these systems often skimp on by specifying a single-acting hand pump. In these pumps, hydraulic fluid is only pressurized on the downward stroke of the pump’s lever. Doering Inc., Clear Lake, Minn., does this concept one better with its DCHP163 cartridge-style hydraulic hand pump.
The standard ISO symbol for a hydraulic hand pump, left, belies the double-acting operation of Doering’s DCHP 163 hand pump. The ISO symbol implies that the pump draws in hydraulic fluid from the bottom port when the hand lever is raised and discharges fluid through the upper port when the handle is lowered. In actuality, Doering’s pump draws in and discharges fluid for both pull and push strokes.
The it is constructed in a cartridge configuration, the but is designed to be installed in a manifold, often referred to as a hydraulic integrated circuit. The pump is also double-acting, so hydraulic fluid is pressurized with both downward and upward strokes. This can cut the time to extend or retract a load in half. Doering also implemented a piston design so that the same force is applied for both upward and downward strokes.
The DCHP163 Series fits in the industry-standard 16-3 cartridge cavity and is compatible with a wide variety of different hydraulic fluids, including water glycol. The cartridge mounting also lets users rotate the handle 360 deg. for easy access. The pump is designed for an operating pressure of 6,500 psi (450 bar) and displaces 0.54in.3 (8.87 cc) per cycle. It can operate at temperatures from −40° to 212°F (−40° to 100°C) with standard seals, and to 400°F (204°C) with fluorocarbon seals.