High Pressure Pump
All manufacturers of pressure washers consider the high pressure pump as the heart of a pressure washer. This is because pressure pumps are responsible for generating the pressure needed to make a pressure washer what it is – a cleaning equipment that utilizes high water pressure to clean. The most popular type of pressure pump that can be found on pressure washer these days is the triplex, positive displacement, reciprocating plunger pump. These pumps are widely used because they offer a smooth flow with equal volume and pressure throughout. It generates the pressure by pushing the fluid through a restrictive nozzle and not on the pump itself.
High end pressure pumps use solid ceramic plungers and come with an unloader, a safety mechanism that regulates the flow of exiting water, a pressure hose fitting, and a thermal relief valve. Some of the well known brands of high pressure pumps are Cat, Comet, General, and Giant. They offer lasting seals and superior construction by using high quality components which results in continuous use with minimal maintenance. There are others however that use forged brass manifold which has a lifetime guarantee.
Pressure pumps that are made for industrial use are often abused by a battery of constant heavy work which is why they have their own sets of standards. High pressure pumps for industrial applications often have die-cast bodies, brass heads, special valve cages, oversized bearings, and cooling fins to be able to take the abuse and provide extended life to the pressure pump itself.
High pressure pumps can have left or right mounting options, they can be placed on different orientation, they can be self-priming, frame-mounted, have multi-stage, be corrosion resistant, and have variable speeds. The truth is reviewing the different options available can take some of your time, but will overall be truly worth your time as you will have a good idea on what these options are for, thus preventing you from making misguided decisions.
The thermal relief valve of your pump is essential to the longevity of your pump. It is responsible for relieving the pressure caused by the increased volume of liquid due to an increase in temperature. This prevents overheating caused by recirculating water. A pressure pump is notably able to handle water that is 68° in temperature. However, if the water gets a bit hotter, the formation of air bubbles can explode upon reaching the high-pressure chamber and it can blow a hole in the pump. This is why it is always advised not to leave the unit running for more than 2 minutes in bypass mode without depressing the gun. Triggering the gun will send cool water in to cool down any heated water. If you are unable to do this, then it is simply best to just turn off the unit.
Pressure pumps can be used either for transferring water, such as on a pressure washer, or for creating suction. Both ways still creates fluid displacement. It is important to know what type of fluids you use on your pump as this will determine the life of your pump. If you plan on running any chemicals inside the pump, it is important to check first the listing on your manufacturer’s manual so as to prevent any buildup of corrosion or damage to the pump. Stainless steel types are very much capable of withstanding heavy chemical use.
If you maintain you unit and you pump regularly, it is not uncommon to see it lasting for many years. Some of the regular maintenance your pump may require would be changing the oil every 3 to 5 months. It is also a good idea to check the level of the oil before every use. Checking some of the equipments is also beneficial as there are some instances that the pump was thought to have been failing when all the while it was just the nozzle that has become clogged.
The pressure pump usually sits at the core of the pressure washer. In order to generate pressure, the high pressure pump needs to be powered either by an electric motor or a combustion engine. There are basically two ways that these powertrain can deliver their power to the pressure pump, either through belt drive or through direct drive.
Belt Drive – a belt drive basically runs using a pulley system mounted on a solid shaft and a motor. This type of configuration allows the pressure pump to run at lower RPM as compared to a direct drive. The crankcase of the beltdrive contains a larger oil capacity. This, along with the low RPM that the belt drive generates means the pump runs at much cooler temperatures. One of the main advantages of using a belt drive is that the pump receives less vibration. This is possible because the belt and pulleys acts as shock absorbers. Aside from that, the pressure pump is also isolated from the heat that the motor generates. Although there is reduced efficiency in using this configuration as some of the energy is lost in the belts and pulleys, the pressure pump on the other hand is not subjected to too much wear due to vibration and heat.
Direct Drive – a direct drive contains a hollow shaft which can slide into the drive shaft of the motor. The flange of the pressure pump is made to be mounted on the face of the motor where both the drive shaft and the shaft of the pump are connected. Since the pump is directly connected to the motor, the pump is able to achieve the same revolutions as that of the motor. Using this type of configuration allows the manufactures to make a more compact pressure washer design. In addition, since there are less moving parts, the unit can also be retailed at a lesser price. The downside of this type of configuration however is that since both the pump and motor are spinning at the same revolutions per minute, not to mention the vibration created, the pump is subjected to more wear and tear, which is why the lifespan of the unit is greatly reduced.