Design and principle of operation of a high pressure washer

Design and principle of operation of a high pressure washer

When it comes to pressure washers, most people think of a car wash tool. In fact, this is a multifunctional device for cleaning various surfaces, for example, the facade of a house or garden path, pipes for various purposes, and so on. How does this sink work and what is the principle of its operation? Are there any fundamental differences in surface cleaning devices from different manufacturers?

What is included in the design of a high pressure washer?

A high pressure washer (hydrodynamic cleaning) is a fairly simple mobile device that takes up little space. The main design elements of this unit are:

• Electrical engine;
• pump with automatic motor switch;
• a hose through which water is supplied;
• hose with high pressure gun handle;
• housing with power cable;
• additional nozzles.

Let's figure out how these elements function among themselves, making the device work as a whole.

Why does pressurized jet make things cleaner?

Let's start with the fact that water itself copes well with pollution, and there is a good scientific reason for this. Its molecules have a slight electrical polarity (one end is positively charged and the other negatively charged), so they tend to be attracted to things on their own.

Detergents (soaps, chemicals) help water do its job even better by breaking down oil and fat molecules. But some types of stains just won't budge, no matter how hard you try. Then a high-pressure apparatus will come to the rescue. It uses a narrow stream of high pressure hot or cold water to break down the structure of the dirt. Because water moves quickly, it hits the dirty surface with high kinetic energy, hitting the dirt and dust like thousands of tiny hammer blows.

Water breaks down dirt, but it does not damage even the hardest surfaces. However, it is usually always recommended to test the jet in a safe area. That is why Karcher has released a new series of Full Control mini-washers with a pressure regulator depending on the surface. The handle has surface-designated touch buttons, so your surfaces are now safe!

Pump

The hydrodynamic cleaning unit can be equipped with either a piston, plunger or any other pump. The performance of the entire high-pressure washer and its service life depend on the quality of the pump as a whole, and in particular on the material of the pistons and piston chambers. Inexpensive models often use single piston pumps. And variants of devices in a more expensive price category, as a rule, are equipped with pumps with several plungers (pistons).

Another difference between budget versions of the unit is that the piston group parts are made of plastic and are not durable. Premium sinks use ceramic pistons or made of alloy steel, and the body is made of aluminum alloy. Moreover, in expensive models, the piston chambers and the pistons themselves are matched to each other with the highest precision. And the working surface of these parts is processed just perfectly.

Main features and types of plunger units

In terms of design, specificity of operation and structure, a plunger-type pump is similar to a piston unit. The presence of a special piston, in the form of a plunger, is the main distinguishing feature between plunger and piston ones. Due to the creation of high pressure in the system, plunger-type pumps are not used in everyday life.

High pressure units are mainly used in the chemical and oil refining industries. The use of such devices makes it possible to mix solution components with high precision in the proportions required for the process, which is very convenient in production processes. The design features of these pumps are inherently different, and therefore plunger devices are divided into:

• volumetric;
• non-volumetric.

Due to the specific nature of the operation, the plunger pump unit is made to be wear-resistant, sealed, durable and ensure continuous and reliable operation of the plunger.

These units are high-performance devices with high efficiency, which is up to 90%. According to the properties of their design features, plunger devices are classified into types:

• vertical;
• horizontal;
• manual;
• auto;
• multi-plunger;
• multi-cylinder;
• with sealed cylinders.

Plunger pump HAWK 610003

Plunger pumps have a number of advantages over their analogues, which clearly stand out:

• the lubrication system is thoroughly developed and has good access for the consumer;
• due to the design, it is possible to change parameters and characteristics to suit the customer;
• have clear and simple operation of the device, as well as easy installation;
• it is possible to increase or decrease the working pressure in the hydraulic system by changing the number of pistons groups.

Main Applications

1. In the chemical industry for the manufacture of chemicals that do not react chemically with metal.
2. In the chemical industry for drilling wells and transportation and subsequent processing of petroleum products.
3. In the energy sector for the manufacture of electric drives for steam generators.
4. For hydraulically driven equipment in mechanical engineering.
5. In public utilities to perform repair work related to hydraulic communications.
6. In reverse osmosis devices intended for the food industry.
7. High pressure water plunger pump is used for car washes.

Triple plunger pumps

Science and industry are developing and, based on practice, scientific research, analysis of the design features of pumps, etc., small-sized unified three-plunger pumps have been designed and put into production.

The triple plunger pump is a fourth generation pump of the NPG type. These devices differ from previous generations in the diameter of the main element (plunger), hydraulic box and properties of the valve units of the system. Such high pressure systems usually have a basic configuration:

• pressure sensors, alarms and pressure gauges;
• safety valve;
• shut-off or stop valves;
• filter for water purification;
• gear oil pump>;
• liquid cooling system;
• safety valve.

2.1 Benefits

Axial - high pressure plunger pump has many advantages. These include:

1. The rhythmic operation of the mechanism, which is ensured by pressure and discharge valves on both sides of a special chamber;
2. Simplicity, as a result of which it is not difficult to make a high-pressure plunger pump with your own hands and install it;
3. Power;
4. Long-term operation;
5. Modular design, thanks to which, if necessary, you can order the production of a plunger pump with individual characteristics, for example, for a car wash;
6. Compliance with international standards;
7. A wide range of pumping products, with different temperatures and consistency.
8. The compactness of axial plunger units allows saving the working surface;
9. The ability to regulate the rotation speed keeps the situation under control;
10. Possibility of changing the working volume of the device;
11. High performance.

2.2 Cons

In addition to the advantages, the use of axial plunger structures also has disadvantages. They occur during intense work and are expressed in the appearance of pulsation and vibrations. Their negative impact can be prevented by attaching additional devices to the high-pressure pump with your own hands. They can become working plungers. For example, a triple plunger pump does not allow vibrations.

Plunger pump HAWK 610003

Improper use of the device can lead to frequent breakdowns, which will be difficult to fix. Therefore, if you lack such experience, you should not install or repair plunger pumps yourself. Time will be lost and quality may suffer.

Electric motor

The electric motor occupies almost the entire space inside the housing of the hydrodynamic cleaning unit. It also accounts for the bulk of the weight of the entire device. Traditionally, a motor with brushes is installed in the sink. But there are units without brushes. Their fundamental difference is the development of a greater resource and less heating during operation.

One or two fans are installed on the engine axis. They are necessary to cool the “heart” of the washing machine. If two fans are used, one sucks in air from outside, directing it along the rotor. The second is used to exhaust hot air from the opposite end of the engine.

The electric motor shaft is connected to the gearbox. With its help, rotation from the shaft is transmitted to the pump. In both cheap and expensive models of units, the gearbox housing is made of high-strength plastic.

Engine

This is the main power source for the pump; there are gasoline and electric modifications, but the latter are much more popular. The motor carries out the procedure of turning the pump on and off, which constantly alternates during the use of the car wash. And since the starting voltage is much higher than the rated voltage, the likelihood of overheating in such an intense rhythm increases significantly. Therefore, just like in a car, an effective cooling system is needed here.

The majority of high-pressure devices use air to lower the temperature, but the same German “Kärcher” already does, its efficiency is an order of magnitude higher than that of the classical scheme. It is possible to mitigate the consequences for the engine from frequent starts with the help of several fans. One, located at the end of the installation, draws air into the middle of the stator, where the second one comes into action, with the help of which the already hot air ends up outside.

Circuit breaker and hoses

The circuit breaker is connected to a pressure sensor and is an important element of the pump design. It is triggered when the sensor shows that the permissible level for operation has been exceeded, and the engine stops. And as soon as the pressure begins to drop, the “heart” of the sink starts up again. The process of restoring the water supply starts instantly.

The design of the hydraulic cleaning apparatus is such that two pipes are connected to the pump: inlet and outlet. The incoming pipe is connected using a hose to a water supply source, which can be either a water supply or a container filled with water. A high-pressure hose with a pistol handle is connected to the outlet pipe.

Frequent malfunctions

Often, during operation, the sink ceases to cope well with its duties. Very often the pump in the devices starts to work poorly , which causes the performance of the device to drop. The reason must be sought in the wear of the seals in the pump mechanism. They need to be replaced with new ones. But if this happens all the time, you need to pay attention to the quality of the water . It may contain a large amount of abrasive impurities.

If the model is equipped with a pressure regulator, the rubber rings may wear out. As a result, the pressure, density and washing ability of the water stream decreases. If repairs are necessary, the question arises of how to disassemble the Karcher in order to determine the cause of the breakdown and begin repairing.

The pressure washer does not turn off

Most often this happens if :

• the valve is jammed or the spring is compressed;
• The microswitch has failed;
• the tightness of the hose is broken;
• there is a malfunction, the device does not have enough supply water.

Does not create pressure

When the electric motor is running, and when the gun trigger is pressed, water flows with low pressure or does not flow at all, the first thing you need to do is check the tap of the water supply system , it may be closed.

A possible cause is blockage in the bypass valves at the pump inlet. In order to check how they work, turn off the tap and turn on the engine; due to the discharged pressure, the hose will begin to shrink. It is necessary to properly connect the sink to the water supply. The pump should run for 2 minutes without connecting a high pressure hose to the nozzle. As soon as the water flows without air bubbles, turn off the pump, put on a hose and a gun. Turn off the installation, disconnect the inlet main hose . Use pliers to pull out the fine filter and rinse under running water. If this does not help, you need to contact a professional.

The pressure washer is jerky

reasons :

• water leakage through the housing or due to a leak in the hose;
• jamming of the lever piston rod;
• incorrect operation of bypass valves;
• weakening of the spring, due to which the lever does not return to the desired position when the pressure drops.

Problems not related to disassembly and assembly can be solved with your own hands, wash the nozzles and filter, and check how the hose is secured. But even after this, the device rarely begins to function normally; you need to contact the specialists.

The pressure washer turns on and off

Check whether the channel is suitable for water supply . The nozzle is cleaned, making sure that the pressure of the incoming water is high enough without interruptions. It is necessary to check the voltage in the electrical network. The unit will not work properly if air bubbles form in the hose. Experts advise paying attention to the condition of the pressure valve. Loss of performance can result from failure of one of the valves. It is difficult for a non-specialist to repair this fault.

You can handle such minor problems as checking the electrical circuit of the main switch Major faults where the device has to be partially or completely dismantled are best left to specialists. They will replace the pump cover, replace old parts with new ones, and clean the valve seats. It is impossible to do such work at home without a special precision tool. The craftsmen know how to assemble a Karcher so that the device functions normally.

During the warranty period for the purchased high-pressure washer, you are not allowed to disassemble the device yourself. You can only clean it from the outside and assemble it for further use. Intervention in the design and unauthorized repairs deprive the owner of warranty and service.

You can fix simple problems yourself, but generally you need to contact a service center

Shampoo does not foam

Premium models are equipped with a compartment for filling chemicals - special car shampoos . A Karcher washer may not foam the shampoo if it does not meet the minimum requirements for using the available nozzle.

In some cases, the problem lies in too hard water or improper preparation of the foam composition prepared in violation of technology.

Karcher will not produce foam due to contamination of the foam tablet , which is called a foam mesh. This is a consumable item. It is sold separately and must be replaced.

Check the jet from the washing gun side. To do this, unscrew the adapter from the nozzle and unscrew the nozzle using a slotted screwdriver. To restore functionality, it needs to be cleaned with a thin wire. Inspect the air holes on the fitting. They must be clean on the outside as well.

Don't forget about filtering

Often, a hydraulic cleaning device is connected to a source of industrial water. This means that the liquid may contain various impurities. The use of such water can lead to malfunction and failure of the washing unit.

To prevent negative consequences, it is recommended to add another element to the hydraulic cleaning device - a filter. It should be installed in front of the hose connected to the inlet pipe. And in special cases, experts recommend installing a coarse filter, followed by a second one for fine cleaning.

Selecting a device

The performance and ease of use of a Karcher machine for washing a car largely depends on the reliability and build quality of the installation itself. To ensure that the process of washing your car brings only pleasant impressions, take a responsible approach to choosing a car wash. The range of devices of this type is quite large. The market offers expensive branded units, budget models, as well as very cheap devices. Below are tips to help you choose a good vehicle care device.

• Performance. For home use, the potential of models capable of producing up to 12 liters per minute is sufficient. Their power is up to 3 kW. More productive models are equipped with gasoline engines and are intended for professional use.
• Pressure. To clean machines, a pressure of 70-150 bar is sufficient. The maximum value is 170 bar. If water is supplied under higher pressure, there is a risk of damaging the paintwork.
• Pump material. Don't buy a sink with a plastic pump. It doesn't last long. Pumps made of silumin, aluminum or brass are more reliable. Ceramic pumps are used to equip premium segment models.
• Filter. Manufacturers equip units with disposable and washable filters. The latter are more convenient because they have a large working resource.
• Automatic motor stop. Overheating of the electric motor can lead to its breakdown. The automatic stop option prevents overheating, protecting the engine from premature failure.

Also, when purchasing a car wash for a garage or home, pay attention to the model’s equipment. It is convenient if the delivery kit includes different attachments for performing different operations. As a rule, manufacturers equip high-pressure cleaners with a flat, mud cutter, regular and rotary brushes. To make your choice easier, read reviews of popular models and read customer reviews.

How does a high pressure washer work?

The operating principle of the hydrodynamic cleaning device is quite simple. From the point of view of the average person, it can be described as follows. The high-speed jet destroys dirt adhering to the surface through mechanical action. Simultaneously with this process, the fallen off parts of the contamination are washed away with water.

From a technical point of view, the principle of operation of a high pressure washer can be described a little differently. Water from the source flows into the pump. There, the fluid pressure increases to the required value. And water flows to the pistol handle under pressure. Then, when you press the button, it sprays.

Thanks to various nozzles, the shape of the jet can be adjusted and changed. Parameters such as jet speed and water flow are decisive in determining the efficiency of the unit. And not pressure, as many people think. It turns out that the selected nozzle directly affects the quality of surface cleaning work.

Precautionary measures

A home sink is a useful, but potentially dangerous device that can cause injury to the operator if not handled carefully. Before starting work with the installation, be sure to read the instructions for use. Here the manufacturer answers all questions that the user may have in the process of preparing the equipment for work or directly when washing the car with a Karcher. Particular attention should be paid to safety precautions. Compliance with them will ensure safety for the operator and protection for the installation from breakdowns.

• Do not use items or materials that are incompatible with cleaning equipment. This includes toxic substances and flammable compounds. Otherwise, a fire or explosion may occur.
• Use the equipment as intended. Do not direct the water flow towards animals and people. High pressure water can cause serious injury.
• It is strictly forbidden to use the washing machine to wash electrical appliances. Also, do not direct the jet at the device itself. This will not only lead to failure of the washer, but also to electric shock to the operator.
• You should not work outdoors if it is raining outside. There is a high probability of a short circuit.
• Do not allow children, teenagers, or people who have not previously read the operating instructions to operate the unit.
• Do not touch the power cable or plug with wet hands.
• Does not turn on the unit if it is discovered that the power cable is damaged or the integrity of the hoses is compromised.

A high pressure washer is a useful household appliance. It will work for a long period without failures or breakdowns if it is used for its intended purpose and certain rules that relate to the process of washing, maintenance and repair of the installation are followed.

Plunger pump for car wash - advantages and disadvantages

To service car washes, only one type of pump is used – plunger units. They have the following advantages:

• Ease of operation;
• High performance and power;
• Able to create high pressure in conditions of a small amount of water;
• Reliability and durability;
• Low cost for most models;
• Small dimensions and low noise level.

On average, the efficiency of plunger pumps does not fall below 90%. This figure is much higher than that of other types of equipment.