Comparison Black&Decker HVLP200 vs Black&Decker BDPS400

The power consumed by the operation of an electric tool (see "Type").

Most modern spray guns, even performant ones, have a rather low power: for example, models with more than 1 kW are extremely rare, and in most cases, power consumption does not exceed 500 W at all. So when connecting such equipment to sockets, there are usually no problems; only single units of high performance, requiring 3.5 kW or more, have to be connected according to special rules (directly to the shield). In other cases, data on power consumption is most often not needed for normal use and may be required only for specific tasks — for example, to calculate the load on an autonomous generator.

Nominal air pressure in the spray gun.

The general meaning of this parameter depends on the type of instrument (see above). So, in pneumatic models, nominal pressure data is required for connection to an external compressor. It is this pressure that this compressor must create at the inlet to the atomizer; too low values will lead to a decrease in efficiency, too high are fraught with breakdowns and even accidents with injury to others.

In turn, for electric models, the nominal pressure is the air pressure created by the unit's own compressor; the complete atomizer was originally designed for the same pressure. So in this case, this parameter is more of a reference than practically significant; it may be useful only for connecting replacement nozzles to the compressor (or vice versa, for using an existing nozzle with a third-party compressor).

As for specific pressure values, they are primarily determined by the spray system (see below). The diversity here is quite high: the most modest units give out less than 2 bar, 2-5 bar compressors are quite popular , 5-10 bar models are relatively rare, and some powerful performance solutions provide a pressure of 100 bar or more.

Consumption of paint or other material (for example, mortar for plaster) when the spray gun is operating in normal mode.

The higher the flow rate, the more material the tool can apply per unit of time, the better it is suitable for processing large areas and for applying thick coatings. On the other hand, not all types of work require high productivity, and sometimes relatively low consumption is optimal. Detailed recommendations on this subject for different situations can be found in special sources.

The diameter of the nozzle at the outlet of the spray gun.

It is from this nozzle that paint or other working material comes out. And the productivity and spot size at the exit depend on the diameter. Accordingly, larger nozzles are better suited for processing large surfaces, while smaller nozzles provide greater precision and accuracy. Thus, this parameter is directly related to the type of device (see above). There are also spray guns with a replaceable nozzle, when more than one nozzle is provided in the kit, which expands the possibilities of using the device.

Spray method used by the spray gun.

— Pneumatic. Pneumatic (air) spray tools work on the principle of a spray gun: paint particles are captured by the air stream flowing from the nozzle and transferred to the surface to be painted. This method is standard for pneumatic tools, but it is also common in other types (see above). The advantages of pneumatics are the excellent uniformity of application and the aesthetic appearance of the resulting coating, as well as its versatility — it can be used both for small jobs and for large surfaces, for objects of any complexity and with almost any type of paint and varnish materials. And the equipment is relatively simple and inexpensive. The main disadvantages of this method are high fogging (which requires good ventilation and protective equipment, and also increases material consumption) and the need to dilute the material to a working consistency (which, in turn, affects the consumption of solvents).

— Airless. Airless spraying is based on forcing the paint material with a special high pressure pump; roughly speaking, the spray gun "spits out" the paint through a nozzle, spraying it into a stream of the desired shape. The key advantages of this method over the pneumatic one are, firstly, high productivity (including due to higher efficiency and lower material losses), and secondly, the absolute minimum of fogging. It is also worth noting the low consumption of solvents and a clear...border of the edges of the treated area. At the same time, the uniformity and appearance of the coating during such work is much worse than with air spraying, the uniformity is lower, and the equipment turns out to be expensive and difficult both in itself and in maintenance. Therefore, airless spray is recommended for large areas where productivity is more important than high quality. In addition, this option is indicated for rollers (see "View"): in them the technology is somewhat different from that described, but it also does not imply a supply of compressed air.

The type of spray system used in the device. Different spray systems differ in the format of work and, as a result, in individual practical nuances of use:

— HP (High Pressure) / CONV (conventional). One of the most famous and popular spray systems. The air pressure at the inlet and outlet of such spray guns is approximately the same. The advantages of HP systems are the simplicity of design, large working width, high paint application speed and relatively low air consumption. At the same time, the percentage of paint transfer in such sprayers is very low — more than half of the applied material bounces off the surface due to high speed and settles on surrounding objects. Another disadvantage is that the flow from the HP atomizer picks up fine dust and other "flying debris" heavily; because of this, additional grinding and polishing of the painted surface is often required.

— RP (Reduced Pressure). Modification of conventional (HP) atomizers, characterized by a slightly reduced outlet pressure. This allowed for some improvement in the transfer coefficient and reduced debris levels while maintaining the advantages of good performance, uniformity and low air consumption. Nevertheless, according to these indicators, such devices are still inferior to low-pressure models.

— HVLP (High Volume Low Pressure). Spray system with reduced outlet pressure (a...pprox. 0.7 bar) and large air volumes. One of the key advantages of such devices is a high ink transfer coefficient of at least 65%. In addition, the low speed of the paint supply reduces the level of debris: there are relatively few turbulences that “pull” debris along with them. The main disadvantage of HVLP systems can be called high air consumption; not every compressor can handle such an atomizer. In addition, they require additional filters to protect against oil and moisture entering the air during high compressor loads; and you can work with such a device only at a short distance (usually up to 15 cm), and in order to avoid drips, a certain skill is required.

— HVLP-II (New High Volume Low Pressure). The second generation of HVLP (see the relevant paragraph), which has a number of improvements compared to the original, but is generally similar.

— LVLP (Low Volume Low Pressure) / Trans-Tech. Spray systems developed as an improvement to HVLP. With the same advantages (high transfer coefficient, minimum debris), they consume much less air and have softer requirements for compressors and hoses. In addition, LVLP systems are less sensitive to pressure drops, and the effective spraying range in them reaches 25 – 30 cm. Of the notable disadvantages of this option, one can only mention a rather high cost.

— HVMP (High Volume Middle Pressure). Spray systems with high air flow and medium outlet pressure. Compared to HVLP, due to the higher pressure, they give a slightly lower ink transfer efficiency, but greater uniformity and range.

— LVMP (Low Volume Middle Pressure). Spray systems with low air consumption and medium pressure; a kind of modification of LVLP, characterized by higher pressure. Due to this, the cost is somewhat reduced, productivity, uniformity of application and capture width are increased; however, paint consumption is higher and the finished surface is rougher than original LVLP.

— HTE (High Transfer Efficiency). This marking is used in spray systems for which a high transfer coefficient is claimed by the manufacturers. In terms of characteristics, they are most often similar to LVLPs (see the relevant paragraph) — in particular, they have a rather large effective range. However, specific features in each case should be clarified separately.

— EA (Excellent Atomization). The main feature of such systems, in accordance with the name, is a very high degree of atomization of the material. Other performance characteristics in such systems may be different, these points should be clarified separately.

— HEA (High Efficiency Airless). Proprietary airless spray technology (see "Spray") used in the Wagner brand technique. Reduces paint wastage by more than 50% compared to more traditional systems, as well as more even material distribution, according to the creators. Suitable for water and oil based coatings.

MP (Middle Pressure). Transitional option between the HP and RP described above: it provides a slightly lower working pressure compared to HP, but not as low as in RP. For a number of reasons, it did not receive distribution.

HD (Heavy Duty). A marketing designation used on individual sprayers, typically high-capacity, high-volume sprayers. The specific characteristics of such systems should be clarified separately.