We have built up considerable expertise in using our Micropac hydraulic hand pumps as standby pumps and for manual overrides.

These are used throughout the world in hostile environments including deserts, the tundra, undersea and in punishing marine splash zones. We can control single and double acting hydraulic actuators. Here an actuator is based on a hydraulic cylinder. If you need to understand the difference between a single and double acting actuator or hydraulic cylinder, look at our YouTube video. A hand pump can invariably provide a simple and durable source of power for small hydraulic actuators. They can also be valuable on larger systems but may require a lot of pump strokes. If it is an real emergency, users will tolerate a lot of strokes. Pumps are also used for charging up accumulators if power fails. These units are also used for wellhead control systems.

Pressures run up to 1000 bar on fluids including mineral oil, water glycols and synthetic fluids. Temperatures run down to -55 degrees C. Materials include marine grade aluminium alloy, carbon steel and 316 stainless steel. We also offer specialist ATEX and IECEx certified hand pumps. Talk to us if hand pumps for hazardous areas are your particular requirement.

What are the main issues in actuation, standby and manual over ride hand pumps?

Different customers have varying priorities, but this is our suggestion after 35 years.

A key consideration is durability and corrosion resistance so that the unit will work well when it is eventually needed, even after long periods of inactivity. This has got to be the key objective. A standby unit is of little use if it is seized up or the piston rod badly corroded on the day it needs to be used. External corrosion is one big concern, although on a high integrity system, galvanic corrosion of wetted parts will be equally important. In the limit, designers will specify 100% 316 stainless equipment so as to have no dissimilar materials within their hydraulic components. Contact us to discuss your application for low corrosion pumps.

“Can I buy a cheap unit and paint it in an epoxy coating?” Our answer would be that a two pack coating system from somebody like Cromadex can be very effective with certain provisos when used on hydraulic components. A 316 stainless steel unit is always a better way of achieving manual hydraulic power but coated aluminium alloy or carbon steel is still widely used. Carbon steel surfaces will need to be prepared so the coating will key. They normally recommend blasting the surface. That isn’t going to work with mechanisms and hydraulic components. You do need corrosion resistant piston rods and needle valves, which a cheap pump won’t have. Our very effective engineering solution on some Micropac product ranges is to offer a carbon steel pump with the bronze bearing, hard chromed 316 stainless rod, stainless needle valve assembly and a 316 stainless handle mechanism. The rod and needle release valve can be masked carefully and the mechanism removed for painting then refitted. Talk to us about epoxy coatings on hand pumps.

Another important consideration is extreme operating conditions. High ambient temperatures in desert conditions are one extreme, but in recent years we have seen more equipment being specified for very low temperatures. Large areas of the world are specifying -30 degrees C, but in the extreme, equipment may have to potentially run down to -55 degrees C. The reality is that this low temperature limit isn’t just academic, but very low temperatures are seen in winter.

Where there are a number of units, cost is an issue. You can’t really deny it. If you are buying 100 units, a saving will mount up. Because our equipment is modular, we can offer hybrid materials. For example, on our C10-2 cartridge pumps, we can use a proven hard chromed 316 stainless piston rod from the MT-6 unit but fit the hard anodised alloy 6082T6 clevis and swivel from the MT-3 unit. The cost savings can be substantial in a large installation.

A small space envelope is generally appreciated, if only for shipping finished assemblies worldwide. Units such as the MT cartridge pumps and PPS system builder units have a swivel handle clevis that can be parked out of the way for transit, storage and everyday operation then deployed to suit the operator when needed. That makes the handle mechanism less vulnerable to damage and reduces the space envelope for the overall design.

Serviceability and extended service life is in our DNA. Expect our equipment to be serviceable and not throwaway. We can offer comprehensive service kits at modest prices and short notice. In remote locations, our customers cannot accept throwaway equipment.

Integration of hydraulic hand pumps into a larger system offers benefits and challenges. Over the years, we have designed manifold pumps comprising a single acting hand pump, a bypass valve to take the hand pump out of the circuit, two speed control valves to control cycling speed, a make up check valve from the reservoir and a low pressure reservoir return relief valve to hold up the tank line pressure. A four way directional control valve can be mounted on the same pump manifold block for double acting actuators. This type of manual over ride unit can be dramatically cost effective for actuator manufacturers. Another option which we have sold in large numbers over many years is our miniature MC series hand pump with its small integral reservoir or 175cc additional reservoir then fitted with a three port ball valve or a miniature four way directional valve. For small actuators, whether single or double acting, this unit can offer an excellent solution. Another easy route to integration and cutting excessive use of fittings is to mount the pump on a fixed reservoir, specify two extra reservoir bosses and two check valves fitted. One provides the make up check valve and the other a low pressure relief valve to hold up the pressure in the system.

Once a control system reaches a level of complexity, actuator manufacturers and control system designers will specify individual discrete components and pipe them up. This is invariably so for 316 stainless equipment, although one Scandinavian customer has standardised on our 316 stainless version of the CETOP3 cartridge slice pump MQ series within their control system. This simplifies connections and reduces the space envelope. Our Micropac PPS 100% 316 stainless System Builder hand pump was our product for designers selecting discrete components for a complex system. It has inlet and outlet check valves, as small space envelope and is fitted with Swagelok tube fittings for a range of male and female threaded adaptors.

Contact us to discuss Micropac hand pumps in hydraulic actuation and standby applications.

Micropac products most widely used in actuation and standby are:

Our Micropac MW Series pumps are most commonly specified. The MW-A, anodised alloy/stainless wetted parts and MW-3 stainless 316 units are the two options available. MW units are either supplied as hand pumps on their own or on fixed reservoirs. Four way directional valves can be fitted.

Our MD series two speed hand pumps offer high/low flow for reduced operator cycles on larger actuators and accumulators.

Our MP series hand pumps are commonly used as carry around manual over ride pumps where one unit can service a larger installation with large savings on cost. This type of pump is also widely used for pressure testing and in petrochemical plants. We can fit four way directional valves for double acting operation and supply two or four wheel trolley mounted units with larger reservoirs.

The Micropac MT Cartridge Hand Pumps are used in standby applications where a C10-2 manifold is available. Various material options are available.

Our PPS 100% 316 stainless system builder pumps run up to 400 bar and offer very low corrosion for high integrity control systems. A pure component hand pump with inlet and outlet check valves. Add hold/release valve, relief valve and other system components from Swagelok, Parker or BIS Valves.

Our Micropac MC series miniature pump is an excellent solution for very small actuators. A 26cc reservoir is integrated into this very small body with the option of a 175cc reservoir for larger actuators. Pressures to 400 bar single acting or 172 bar for the double acting unit fitted with a miniature 4 way directional control valve.