Custom-Built Hydraulic Rams
New Custom-Built Hydraulic Rams
A standardised design forms the basis of our custom-built hydraulic rams. The internal parts are of a well-proven design featuring robust sealing and quality materials. The desired cylinder bore size and piston rod diameter is calculated from information supplied by the customer. The ram is then designed to meet the customers’ requirements of stroke length, closed centre length, and mounting style.
We retain stocks of piston rod and cylinder tube materials, also standard ram mounts and internal components. This allows us to produce custom-built rams quickly.
Bore sizes from 40mm to 300mm are available from our standard range. Larger sizes are available as custom-designed rams.
Our hydraulic rams are available in the following generic types:
Double-acting hydraulic rams
Double-acting rams can exert force in two directions. Under the influence of hydraulic pressure, the piston rod of a double-acting ram will both extend and retract. The diagram shows a typical double-acting ram. Pumping fluid under pressure into port A (full bore) will extend the piston rod. The force exerted will be dependent on the cylinder bore diameter and the fluid pressure. Pumping fluid into port B (annulus) will cause the piston rod to retract. The force exerted is dependent on the cylinder bore diameter, the piston rod dia, and the fluid pressure.
Single-acting hydraulic rams
Single-acting rams can exert force in only one direction. Under the influence of hydraulic pressure, the piston rod of a single-acting ram will either extend or retract. The diagram shows a typical ‘out stroking’ single-acting ram. Pumping fluid under pressure into port A (full bore) will extend the piston rod. The force exerted will depend on the cylinder bore diameter and the fluid pressure. The piston rod can only be retracted by the influence of some external force (usually the weight of the load or the machine itself).
‘In stroking’ single-acting rams are similar to the double-acting ram except that fluid is supplied to the annulus port only. The force exerted is dependent on the cylinder bore diameter, the piston rod diameter and the fluid pressure.
Single-acting rams generally only have one service port. The non-pressure side of the cylinder must be vented to allow air to pass in and out as the piston moves. In arduous conditions, single-acting rams can tend to suffer from rusting or pitting of the bore as moist air passes in and out of the non-pressure side of the cylinder.
Displacement hydraulic rams
A displacement ram is a special form of a single-acting ram and can be of the ‘out stroking’ style only. The diagram shows a displacement ram. Pumping fluid into port A will fill the space around the piston rod, as there is a seal between the gland and the rod the oil is contained. Pumping further fluid into the cylinder will displace the volume of the piston rod, and it will stroke out.
The force exerted is dependent on the piston rod diameter and the fluid pressure. Since there is no moist air passing in and out of the cylinder, problems associated with rusting bores are avoided. A disadvantage is that a displacement ram of the same capacity as an ‘out stroking’ single acting ram, will be larger in diameter.
High pressure shear hydraulic rams
Our design capability allows us to produce special rams to suit an exact special requirement of load stroke length or mounting style. This example was produced for a high-pressure heavy-duty application on a metal shearing machine.
Why Clients Use Nicol & Andrew's Hydraulics Division
We Fix Common Problems
When you have problems with your hydraulic rams, we can provide you with a quick and cost-effective solution. No matter how severely damaged your ram may be, we can provide a repair or remanufacture solution.
"Inexpensive" Not Cheap
We repair rams to their original specification using similar materials and methods as the OEM. Many OEMs and dealers rely on selling expensive spares to make a profit, but we can save you time and money by avoiding their game.
Quality Materials and Seals
We have extensive stocks of chromium-plated piston rod material and cylinder tubes, using the same high-quality materials as the original manufacturer. Our suppliers are top-notch, and we only use equivalent or improved-quality seals when repairing rams.