Dismantling a compressor to extract non-ferrous metal is a process that requires not only physical strength, but also an understanding of the structure of the electromechanical unit. Many people hand over old refrigerators entirely, not knowing that inside electric motor hidden is a significant amount of expensive copper, the cost of which at collection points is significantly higher than the price of ferrous scrap. However, in order to gain access to the windings, it is necessary to overcome the durable steel housing, which manufacturers make hermetically sealed.
The process of cutting or disassembling the compressor is associated with certain risks associated with both the use of power tools and the residual pressure of the refrigerant. Freon, even in older models, it can be dangerous if inhaled in a confined space, and the oil that impregnates the windings is difficult to wash off the skin. Therefore, before starting work, it is extremely important to prepare a workplace, personal protective equipment and the right set of tools.
In this article we will look in detail at how to safely open the case, separate the copper windings from the steel core and prepare the scrap for delivery. You will learn about the nuances of working with different types of engines and understand whether the game is worth the candle from an economic point of view. We will also touch on the topic of recycling the remaining ferrous metal, which makes up most of the weight of the unit.
⚠️ Attention: Before starting any manipulations, make sure that the compressor is disconnected from the electrical network and the refrigerant is completely drained from the system. Cutting a sealed tank under pressure can lead to scattering of fragments or ignition of oil vapors.
Preparation of the workplace and the necessary tools
The success of the copper extraction operation directly depends on the quality of preparation. The compressor is a massive and heavy unit that must be securely fixed. For work, you will need a sturdy workbench or a stable surface that you don’t mind getting oiled or scratched. Ideally, if possible, secure the body in viseso that it does not move when force is applied with a grinder or sledgehammer.
The set of tools should be quite wide, since manufacturers use different assembly methods and materials of different strengths. The main tool will be an angle grinder (grinder) with metal discs. You will also need pliers, a hammer, a chisel, and possibly a reciprocating saw if access to the windings through the top is difficult. Don't forget about protective equipment: glasses, gloves and a respirator are required.
- 🛠️ Angle grinder with spare discs for cutting steel 2-3 mm thick.
- 🔨 Hammer and a chisel (or core) for punching holes and separating body parts.
- 🧤 Safety gloves with a rubberized coating to protect your hands from cuts and oil.
- 👓 Safety glasses or face mask to prevent metal shavings from getting into your eyes.
Important Please note that there is technical oil inside the compressor, which when heated can emit acrid smoke. Work in a well-ventilated area, ideally outdoors or in a garage with the gate open. Having a fire extinguisher near your workplace will also not be an extra precaution, since hot shavings can ignite oil vapors.
⚠️ Attention: Use only working power tools. Check the integrity of the angle grinder cable before turning it on, as the work will be carried out in conditions of the possible presence of oil dust, which increases the risk of a short circuit.
Anatomy of a compressor: what is inside and where to look for non-ferrous metal
Before picking up an angle grinder, it is useful to understand what exactly we are dealing with. A standard piston compressor is a sealed steel tank, inside which the tank itself is suspended on springs. The bulk of the mass is ferrous metal (steel), but we are interested in the internal contents of the electric motor. This is where the copper windings are located. motor-compressor. The bulk of the mass is ferrous metal (steel), but we are interested in the internal contents of the electric motor. This is where the copper windings are located.
The motor stator is made of electrical steel plates, in the grooves of which coils are placed. Modern models may use aluminum, but in most old and high-quality refrigerators (especially Soviet-made or brands like Indesit, Atlant, Liebherr), the winding is made of pure copper. The weight of copper varies depending on the power of the motor and usually ranges from 300 to 800 grams per unit.
In addition windings, the compressor has copper refrigerant inlet and outlet pipes, as well as copper elements in the valve group. However, the main volume is provided by the stator winding. The rotor (moving part) is usually made of steel and does not contain copper, so it can be safely taken as scrap. Understanding this structure will help you not waste time recycling unnecessary parts.
How much copper is in different models?
On average, from one compressor with a capacity of 1/5 - 1/4 hp. (liter) you can get about 350-500 grams of copper. Powerful inverter compressors can contain up to 1 kg or more, but their disassembly is more difficult due to complex electronics and design.
Step-by-step instructions: how to open the compressor housing
The most labor-intensive stage is breaking the tightness of the steel tank. Manufacturers brew it in a circle, making the structure monolithic. There are two main methods of opening: mechanical (using a sledgehammer and chisel) and thermal (using a grinder). The second option is cleaner and more controllable, although it takes more time.
Start by cutting off all the external copper tubes that go to the tank, leaving 2-3 cm long “stumps”. This will make the body easier to manipulate. Then make a circular cut with a grinder along the equator of the compressor, approximately in the middle of its height. There is no need to cut right through the metal; it is enough to make a deep groove around the entire perimeter.
☑️ Algorithm for opening the case
After the groove is ready, take a chisel and a hammer. Insert the chisel into the cut and strike, moving in a circle. Sooner or later the weld will fail and the upper part of the body (the “hat”) will separate. Inside you will see the mechanism itself, filled with oil and suspended on springs. Carefully remove it, trying not to spill the contents.
⚠️ Attention: When opening the case, there may be a sudden release of gas or oil vapor. Turn your face to the side and hold the tool at an angle to prevent sparks or splashes from getting on your clothes and skin.
Removing the winding: technologies and tricks
After removing the insides, an electric motor will appear in front of you. To get to the copper, you need to remove the stator with the plate pack. Often the winding is additionally secured with tightening tapes or filled with varnish. In some cases, manufacturers use a method in which access to the winding is blocked by massive steel cheeks.
The most effective way is to saw through one of the sides of the stator (cheek) with a grinder. Make two parallel cuts to knock out a segment of steel, allowing access to the ends of the coils. After this, you can simply knock the copper wire out of the grooves with a chisel and hammer. If the wire is tight, you can pry it up with a screwdriver and pull it out with pliers.
There is also a burning method, when the stator is placed in a fire or oven. Under the influence of high temperature, the varnish burns, and the copper becomes soft and easily removed. However, this method has disadvantages: copper oxidizes, loses weight and quality, and also pollutes the atmosphere with toxic smoke from burning insulation. To obtain the highest grade scrap (Shine or Copper) it is better to use the mechanical method.
- 🔥 Mechanical method: gives pure copper without oxides, but requires more physical effort.
- 🔥 Thermal method: faster, but reduces the cost of scrap and harms the environment.
- 🔥 Chemical method: using acids to dissolve varnish (rarely used in everyday life due to danger).
Do not forget to separate the copper contacts and leads from the main mass of the winding. Often the engine contains a thermal relay, which also contains non-ferrous metals, albeit in small quantities. All aluminum parts (if any) should be folded separately, since the price of aluminum is lower, and mixing metals will reduce the price for the entire weight.
Sorting and preparing scrap for delivery
After successfully extracting the copper, you will be faced with the task of sorting. Metal collection points strictly classify scrap, and the final revenue depends on the purity of the fraction. Copper is divided into several categories: “Shine” (new, clean wire without coating), “Copper” (pure, but can be oxidized or tinned) and “Mix” (with admixtures of solder, insulation or other metals).
Try to clean the wire as much as possible from any remaining varnish, rosin and solder. If there are tinned areas on the terminals (silver coating), it is better to bite them off separately or pass them on as a lower category so as not to spoil the main mass. The steel core plates, housing and springs belong to black scrap (category 3A or 5A), which is sold separately.
| Type of material | Scrap category | Cleanliness requirements | Approximate price (relative) |
|---|---|---|---|
| Copper wire | Gloss / Copper | Without insulation, oxides and solder | High |
| Copper tubes | Copper | Without dirt, paint and steel | High |
| Brass/Bronze | Brass | Separate from copper | Medium |
| Steel (body, plates) | Black scrap (3A) | Without colored inclusions | Low |
It is better to store the prepared scrap in a dry place so that the copper does not oxidize. Although oxidized copper (patina) is also accepted, it will be graded "Mix" or with a weight deduction. Pack non-ferrous metals in separate bags, labeling them so that there is no confusion during delivery. Ferrous metal can be placed in a common pile or large bags.
⚠️ Attention: Prices for non-ferrous metals fluctuate (fluctuate) daily. Before traveling to the reception point, check the current prices and reception conditions (availability of a passport, minimum weight, radiation control requirements).
Economic feasibility and safety of the process
Is the gamble worth the candle? Let's do the math. From one compressor you get an average of 0.5 kg of copper. At current market prices, this could amount to the equivalent of several loaves of bread. However, if you have access to dozens of old refrigerators (for example, when dismantling an old home or working in a service), then collecting copper becomes a completely cost-effective activity.
The main resource you spend is time and health. Working with an angle grinder, inhaling metal dust and oil fumes, the risk of cuts and injuries - all this requires a sober assessment. If you are disassembling one refrigerator “for yourself” for the sake of interest or learning, this is a great experience. If the goal is to earn money, then scale and automation of the process are necessary.
Do not forget about environmental responsibility. Remaining oil from the compressor should not be poured onto the ground or down the drain. Collect it in a container and hand it over to special collection points for waste petroleum products. The steel frame is also recyclable, so do not throw it in a regular trash container, but take it to the nearest scrap yard.
In conclusion, disassembling a refrigerator motor is a technically simple but time-consuming process. It requires compliance with safety precautions and basic plumbing skills. Proper sorting and preparation of metal will allow you to get maximum profit from recyclable materials, turning old trash into a liquid asset.
What to do with leftover freon?
It is difficult to recycle freon in domestic conditions. When you carefully open the tank (if the tubes were cut in advance), the gas has already escaped. If you hear a hissing sound when drilling, this is normal; the gas is escaping. It is impractical and dangerous to specifically assemble it at home.
Frequently asked questions (FAQ)
Approximately how much does copper weigh in a compressor from a refrigerator?
The weight of copper depends on the power and year of manufacture of the compressor. On average, between 300 and 600 grams of copper can be extracted from one standard household compressor. In powerful two-compressor models or industrial units, the output can reach 1-1.2 kg.
Is it possible to burn the winding to quickly remove copper?
Technically it is possible, but not recommended. When burning varnish insulation, copper oxidizes, becomes covered with soot and loses weight (up to 10-15%). Reception points accept burnt copper at the same price (category "Mix" or "Zhzhenka"), which makes the process less economically profitable.
Is the gas inside the compressor dangerous when sawing?
Yes, there is a danger. Old refrigerators may use flammable freon (isobutane), while new ones may use gases that are safe but displace oxygen. Before cutting, be sure to punch or drill the tank in the lower part (where there is no oil) to release any remaining pressure, and work in a ventilated place.
Do you need a passport to hand over copper to a collection point?
In most CIS countries, when handing over non-ferrous metals (copper, aluminum, brass), a passport is required. This is a measure to combat the theft of cables and government property. Without a passport, they can only accept black scrap or require a certificate of the origin of the metal.
How to distinguish copper windings from aluminum?
Copper has a characteristic reddish-golden color at the break and is heavier. Aluminum is silver-white, very light and produces a louder sound when struck. Also, copper is not magnetic, but neither is aluminum, so a magnet won't help. The easiest way is to use a small needle file or file: if the color under the scratch is red, it’s copper.