1. Purpose of the equipment. Used technological processes.
The “APN-250M” unit is designed for sprying of protective, heat-resistant, erosion-resistant and wear-resistant coatings using ion-plasma deposition in a vacuum on parts having an axis of rotation with a circumferential diameter of ≤ 120 mm and a length of up to 200 mm with preliminary ion cleaning of the surface of the products .

2. Features of the physical processes used.
The principle of operation of the unit is based on condensation of the coating from a plasma flow in a vacuum at high and controlled particle energies. The coating material is converted into a plasma state due to the combustion of a vacuum arc between a cathode made of the coating material being applied and the anode of the unit. A vacuum arc burns in the vapor of the cathode material. The source of vapor generation is the cathode microspots of the arc. This achieves congruent evaporation of the cathode material directly from the solid phase (the cathode has forced cooling). The unit can coat 12 products, or a multiple of 24 simultaneously.

3. Technical description. Design features. Equipment advantages.
3.1. List of plant components:
- Chamber;
- Chamber lid;
- Mechanism for lifting and turning the lid;
- Plant drive;
- Cathode and anode;
- Screen system;
- Vacuum system;
- Water cooling system;
- Gas injection system;
- Pneumatic system;
- Control system;
- Control cabinet;
- Ignition cabinet;
- Arc power supply “VVN-1000M”;
- Bias source with arc protection unit;
- Electrical wiring;
- Service area;
- Ignition mechanism;
- Magnetic coil.

3.2. Plant design.
Coatings are applied in a working chamber, which consists of a housing and a cooling jacket. The chamber body and jacket are made of stainless and carbon steel, respectively. Products are loaded into the chamber. The chamber is sealed from above with a hemispherical lid. The lid has viewing windows with which you can observe the spraying process.
The lid has a mechanism for lifting and turning the lid.
The plant drive performs the following functions:
- Reciprocating movement of the cathode relative to the magnetic coil;
- Positioning of the cathode relative to the coil;
- Rotation of products around the cathode;
- Rotation of products around their own axis.
The drive elements are located outside the chamber on the plate and inside it.
The cathode is made of the coating material and is mounted on a cylindrical copper mandrel.
The anode is made in the form of a hollow cooled cylindrical shell made of stainless steel. A magnetic coil, which fixes the position of arc formation on the cathode surface, is placed in the cooled cavity of the anode. The plasma flow is formed by an arc between the cathode and anode. The internal diameter of the anode body is 750 mm.
The screen system protects the chamber body and movement drive parts from the plasma flow and prevents the possibility of arc formation on drive parts that are under electrical potential.
The top screen is attached to the chamber cover. The lower screen can be freely removed without disassembling of cathode, and without dismantling of the drive mechanisms for moving the cathode and rotating the products.
The vacuum system of the unit consists of a forevacuum line designed to create a preliminary vacuum in the chamber, and a high-vacuum line to create a high vacuum. Pneumatic valves ensure safe operation in emergencies. The vacuum system of the unit is equipped with pressure sensors and a controller-based control unit.
The water cooling system cools the chamber body, plate, top cover, cathode, anode, product rotation drive and pumps. Blocks with water flow sensors provide water control and alarms. The system uses a chiller.
Gas injection system.
The gas manifold supplies ionizing inert gas to the chamber through a three-channel regulator. The gas injection system uses gas flow regulators and pulse leaks. The time to reach the specified gas flow is no more than 2 seconds, the time to reach the specified pressure is no more than 10 seconds from switching on.
The pneumatic system controls the operation of pneumatic seals and pneumatic valves. The pneumatic system includes an air preparation unit and pneumatic distributors.
The control system consists of a personal computer and a controller, the functions of which are separated.
The personal computer (the top level of the control system) runs the Windows operating system. The computer enters, edits and records control programs, stores process history files, events and errors.
The controller (lower level) controls the mechanisms of the vacuum system, the spraying process, determines the state of the technological system and dispatches tasks.
The intuitive interface allows you to manage the work cycle, carry out debugging operations, and display the parameters of the process control program:
- arc current and voltage,
- current and bias voltage on the product,
- speed of vertical movement of the cathode,
- rotation speed of the carousel,
- pressure in the working chamber,
- spraying time,
- number of breakdowns,
- number of ignition attempts,
- leakage,
- key operation frequency,
- cooling time of products,
- cooling time after spraying,
- re-training time,
- initial bias voltage,
- saving interval,
- current position of the cathode,
- plant engine hours.