ELECTRON-BEAM MELTING OF TITANIUM

During short time specialists of our company designed and installed specialized electron beam melting furnaces. In a construction of our EB furnaces is applied modern solutions of technological problems permitting effectively melt of titanium sponge, scrap and obtaining their mixed melting. The indispensable technological-economical trends practically using of technology of EBM are connected to creation powerful, stable working in a rather deep vacuum of electron guns, usage of cold hearth for better refinement, automation of a manufacturing process, that constructs favorable conditions for obtaining high quality metal. Series of engineering solutions and technological receptions have "know-how" and made out by announcements for the patents. New electron guns BTP by simple power up to 600 kW which are capable to work at a gas pressure 1,33 Pa, with a high penetrating power of bundle in a cloud of vapour 13,3 Pa allows to realise high speed melting of fissile gas-saturated charge (titanium sponge). It reaches an essential decrease of losses on vaporisation of base metal and alloying dopands, the problem of obtaining pure titanium and its alloys with demanded precision composition is simplified.

Melting with an overflow through cold hearth corresponds to a modern technological level EBM for reaching indispensable quality of indexes of refinement. The horizontal feeding from two sides and share melting of charge is ensured with loading devices with the help of changeable feeders, this changing is carried out without depressurisation of chamber and stopping of melting process. Control of a solidification with the purpose of obtaining given primary pattern and forming of an ingot of the indispensable sizes and configuration (cylindrical, rectangular, hollow shape) takes place in a separate crystallizer or the same time in two or several crystallizers. Forcolling an ingot outside of melting of the camera usage of lockage is stipulated, that increases a loading factor of board up to a level 0,6 & 0,7. Common specification of furnace Melting camera. Is executed from constructional steel with a binding units for chilling, nipples and manholes of service. Diameter of the camera 3,0 m, altitude of 1,5 m.

Electron guns BTP 400-600/30.


Electron-beam gun

High-voltage glow discharge, nominal capacity 400 and 600 kW, quantity of guns — 6 pieces.

Operating pressure range — 1,33 & 0,13 Pa.

Minimum diameter of a focal spot apart 1,5 m from gun is 30 mm.

Maximum frequency of dissector — 250 Hz.

Maximal mass of gun — 50 kg.

Cathodes manufactured of aluminum.

Beam control — programmatic with the help of a time-base generator and programmator of a cycle (controller).

Electron-beam guns

Power supply source — high-voltage transducer (30 kV) with commuting instrumentation and schema of a short circuit protection.

Quantity — 6 pieces.

Power of the transducer — 630 kw.

Main voltage — 380 V.

Vacuum system — Consists of mechanical, booster pumps, ensures working vacuum in melting camera — 0,133 & 1,33 Pa.

Rate of pumping — 100 thousand liters per second. Technological modules — copper water-cooled a crystallizer and intermediate capacitance are collected in the uniform block, changeable for each type size of ingots. The crystallizer consists of a copper battery cartridge and steel body. Loading devices are placed in two cameras and attached to the camera of melting.

These devices have two couples of changeable feeders with dodges of horizontal feeding of remelting charge. Ingot camera. is equipped with the stocked dodge of withdrawal of an ingot from a crystallizer and lock system for its chilling outside of melting camera. Maximal power stroke — 4,0 m. Control equipment and self-controls of process — contains sensors of check of current parameters of melting, computer and coupling unit with plant. Ensures control with conditions under the given program, record and reflex of the information about parameters of process and condition of units blocks of furnace. Cooling system — self-contained, is aggregated on groups in hydroblocks. Ensures of heat pick up from a technological casing hardware, jackets of chilling of the body and vacuum pumps. Water pressure — 4 ATM. Maximum discharge of cooling water — 100 m3/hours.

Control and operating system of electron-beam furnace

Technical characteristics of the furnace VT 01


Characteristics
Magnitude
Main voltage alternating-current by frequency of 50 Hz, V
380
Total power of electronic heating, kW
2400
Accelerating voltage, kV
30
Amount of electron guns, pieces
6
Output of vacuum pumps, m3/s
100
Working vacuum, Pa
1,33 & 0,133
Expenditure of cooling water, m3/h
100
Maximal size of a loading device (h x w x d), m
0,8x0,6x2,0
Quantity of loading devices, pieces.
2
Quantity of feeders on one loading, pieces
4
Dimensions of furnace (h x w x d), m
20x20x16

Effectiveness of melting of titanium sponge in furnace VT 01


Dimension
of ingot, mm
Indexes
Quantity of ingots, p.
Speed of melting, kg/h
Expenditure of power density, kV h/kg
slab — 250x1300x4000
(S x D x L)
1
860
1,46
ingot — 800x4000
(D x L)
1
1100
1,32

Dimensions of titanium ingots melted out in furnace VT 01


Name of argument
Variants of production
01
02
03
04
05
06
07
08
Ingot Diameter, m
0,64
0,64
0,82
-
-
0,4
0,4
0,94
Width x height,m
-
-
-
0,22x1,18
0,42x1,18
-
-
-
Max. length, m
4,0
3,5
4,0
4,0
4,0
4,0
3,5
4,0
Quantity ingots for one process, pieces. 
1
2
1
1
1
1
2
1
Mass of ingot, t
5,7
5,0x2
9,5
4,7
8,5
2,25
2,0x2
12,5
Lockage of ingots
is not present
yes
is not present
is not present
is not present
is not present
is not present
is not present
Working size of intermediate capacitance (h x w x d), m
B x L = 0,4 x 1,2

Description of products


Metal
Shape and dimension of ingots
Usage
Indexes of a quality level
Titanium and zirconium
DIA. 0,2, 0,4, 0,64, 0,82m
(0,165 & 0,42) x1,2 m

L = 4,0m
• waste-handling of wastes

• remelting of titanium    spong

• refining remelting

• obtaining of ingots
high scale of refinement;

absence of actuations (LDI, HDI);

decrease of impurity level of an intrusion;

low expenditures on opening-up of charge;

homogeneity of an elemental composition and structure;

demanded quality for one remelting
Niobium and tantalum
DIA. 0,1, 0,2,0,3, 0,4 m

L = 2,0, 4,0 m
• refining remelting of    primary raw in ingots;

• waste-handling of scrap;

• drop remelting

obtaining of metals with the apart low contents of gaseous impurities;

heightening of plasticity;

heightening of coefficient of a residual specific resistance (K = r /ρ left)
Super-alloys on the basis of nickel and cobalt
DIA. 0,3, 0,4, 0,64, 0,82 m;
DIA. 0,8, 0,1, 0,15 m

L = 4,0 m
homogenising, refining remelting with coldherth • refinement from non-metallic    actuations and interstitial impurities;

• grinding of primary structure

Designed furnaces allow to provide the technological schemas supplying effective melting and refinement of refractory metals, non-ferrous metals both special steels and alloys. The furnaces equipped with monitoring systems of arguments and control by a manufacturing process of melting in manual and automatic conditions, system of sample drawing and proximate analysis during of the melting.

Electron beam equipment


Depending on technological tasks our company in a condition to develop, produce and arrange supplying, during any electron beam melting furnaces with capacity from 100 up to 3600 kW.

According request of the customer of units may be equipped with system of automatic control of technological process, devices of sampling and the express analysis during process of melting.

Offered units may be variously equipped: electronic guns with the cold cathode, systems of power supplies and management of an electronic beam for performance of technological processes: melting, welding, evaporations and other operations which are carried out in vacuum.

Advantage of gas-discharge electronic guns with the cold cathode is simplicity of a design, reliability and durability of work in low and average vacuum, at rather not high cost of manufacturing.

The developed discharge electronic guns are equipped with systems of automatic control and power supplies. Capacity of such guns from several watt up to tens hundreds watt. Characteristics of guns for welding works are given below.


Characteristics


Characteristics
Dot focus
The Profile electronic beam
(disk, tubular, tape)
Capacity of a beam, kW
10
40
Accelerating voltage kV
10-40
10-25
Range of pressure in the technological chamber, Pa
10-10-3
10-10-1
Mode of operation
Continuous, pulse

Our company develops and produces electron-beam equipment for all kind of electron beam process as melting as welding.