1. Purpose of the equipment.
Vacuum furnace “PV-900” intended for heat treatment of products made of titanium alloys.
The product is fed into the oven, heated in a vacuum to a certain temperature, maintained at this temperature and then cooled

2. Technical description.
“PV-900” plant consists of main components:
- Vacuum chamber;
- Front and back lids;
- Cart;
- Recoil device;
- Vacuum system;
- Gas injection system;
- Pneumatic system;
- Water cooling system;
- Electrical wiring;
- Control system.

3.1. Vacuum chamber.
The vacuum chamber has a cylindrical shape and maden of stainless steel sheet. Chamber is mounted on four supports. Flanges are welded to the ends of the chamber to attach the front and rear lids. Chamber has a water jacket for cooling. There are 8 technological zones of water jacket. Nozzles for attaching thermocouples, water-cooled racks and current leads are welded at the chamber body. The chamber has a heating module, which consists of a cylindrical welded frame, and screen thermal insulation. Screen thermal insulation serves to minimize heat losses.
There is a platform for servicing transformer units at the top of the chamber.
Manifolds of the water cooling system and air preparation unit of the pneumatic system are installed on the chamber supports.
Operator's console, mechanism control cabinet and power cabinet are installed near to vacuum chamber.

3.2. Front and back lids.
Both lids made of stainless steel. The lids have a cooling jacket, screen insulation, and vacuum seals inside.
The front lid has two sealed leads for connecting thermocouples, which check the heating temperature of the product inside. The front lid is movable and installed on the cart. The adjusting device fits the seal to the chamber flange.
The back lid is fixed. It has pipes for connection to the vacuum system.

3.3 Cart.
Cart moves along a rail track installed at floor level along the longitudinal axis of the vacuum chamber. The cart, together with the roller support and the plant table, loads the product into the chamber. After heat treatment, the cart unloads the product from the chamber. The cart has 4 wheel pairs and is driven by an electric motor. The speed of the cart is 0.7 m/min. The front lid installed on the cart.

3.4 Recoil device.
The sliding device moves the cart, the front lid and the power and cooling circuits of the front lid. The recoil device consists of guide support frames, an energy chain and a pallet along which the energy chain moves.

3.5. Vacuum system.
The vacuum system makes a vacuum in the chamber.
The system consists of a fore-vacuum pumping line and two lines for creating high vacuum.
The line includes pneumatic valves. The valves installed on mechanical pumps and close automatically during a power outage to prevent oil from escaping from the pumps into the pipelines.
The vacuum system has the required number of sensors to measure medium and high vacuum.

3.6 Gas injection system.
The cage can be cooled by inert gas injection. Gas injection system supplies the chamber with inert gas - argon up to an absolute pressure of 0.5 atm. Inert gas is supplied from an external gas source, for example, a ramp with cylinders.

3.7. Pneumatic system.
The pneumatic system uses to control the pneumatic drives of vacuum valves and pneumatic clamps. The pneumatic system consists of an air preparation unit, pneumatic distribution and pipelines.

3.8. Water cooling system.
The water cooling system supplies and drains the water to cool the furnace and vacuum pumps when the heat treatment process.
The water cooling system is divided into two independent lines and consists of two pressure-drain collectors. The first line, cooling the vacuum system and heating system, includes a chiller; the second line intended for cooling transformers, chambers, jackets, bottoms of covers and current leads.
The water cooling system must be connected to a workshop water supply system with a supply water temperature of 18-20 °C. Flow sensors monitor the flow of water at the outlet. Alarm signal is issued when no water at the drain.

3.9. Electrical wiring.
Electrical wiring provides power supply to the units and systems of the plant. It consists of harnesses with electrical wires, the necessary protective covers and boxes.

3.10. Control system.
The PV-900 furnace has a two-level control system, which ensures that the technological process is carried out in adjustment and automated modes.
A programmable logic controller is used at the lower level of the control system.
The application program performs:
a) in manual mode – the mechanisms and subsystems of the furnace are controlled from the touch screen of the panel computer to complete the heat treatment cycle in the event of a failure of the automatic mode;
b) in automated mode - the automated cycle of operation of the furnace is carried out using application programs from a PC.

The upper level is a panel computer.
The upper level software does:
a) graphical multi-channel interface with the dispatcher, intelligent support for control functions.
b) displaying the status of the plant mechanisms and sensors on the PC screen.
c) indication of the current values of the plant parameters in real time.
d) input and correction of parameters, display of the “history” of parameter values and modes of each technological operation.
e) automatic generation of database records, conversion of the database into the formats of the most commonly used systems.