RU14213U1 - ISOTHERMAL ANNEALING LINE - Google Patents

Abstract

An isothermal annealing line, including a high-temperature heating furnace, a baking chamber, an isothermal holding furnace, connected by a push-type conveyor, characterized in that the isothermal holding furnace is divided into zones, of which the first zone is cooling and is equipped with heat exchange pipes connected to the fan via air ducts, and throttle.

Description

BEST

The useful model belongs to the field of heat treatment of metals and can be used in the thermal workshops of mechanical engineering for isothermal annealing of semi-finished products in order to eliminate their physical or zsmichesky inhomogeneities created by previous work-emi.

A known unit for heat treatment of forgings, containing a sequentially installed heating circuit, a cooling device in the form of a tank with a fan and a heater located above the tank, a transport mechanism, a tempering furnace (see A.S. N 561742, class S21D 9/00) . The aforementioned unit allows one to alternately carry out on it such processes as hardening, normalization, and isothermal annealing.

An isothermal annealing apparatus is also known, comprising high-temperature and low-temperature furnaces, between which there is placed a chill chamber for accelerated cooling. Both furnaces and undercooking chamber are connected by a single pusher-type shvveyor carrying pallets with processed products placed on guides (see.a.s. H 513092, KJ. S21D 9/00).

The disadvantages of this installation include the limited technological capabilities, since it is impossible to provide high-quality isothermal annealing of makusivny semi-finished products. During the annealing of massive parts in your installation, rapid and uniform cooling to the temperature of isothermal exposure is impossible: parts that are not cooled out, especially in the inner deep part, come out of the chamber of the retracted part and phase transformations are equal in equal parts, the parts fail at different temperatures2000100507. d about IT d. S21D 9/00

temperature, which leads to uneven structure and hardness.

The purpose of the utility model is to expand the technological capabilities of the line, which provides isothermal annealing of a wider range of parts.

; 1The goal is achieved by the fact that in the isothermal annealing line, which includes a high-temperature epithermal heating furnace, a busting chamber and a furnace and, isothermal extracting, the isothermal holding furnace is divided into zones, the first zone of the isothermal holding furnace is cooling and equipped with heat exchange pipes connected by air ducts1 with throttle and fan.

This allows you to remove excess heat from the parts and pallets introduced into the isothermal oven 1.

In Fig. A shows a line of isothermal annealing, a horizontal section, in Fig. 2 a section along aa in Fig. 1,

The isothermal annealing line has a passage-type heating furnace 1, pallets 2 with parts, a stirring chamber 3 with a recirculation system 4, a four-zone isothermal aging furnace 5 of a passage type, conveyors 6, 7, 8, 9, 10, And, pushers 12,13, a sprinkler pallets 14. All zones of the isothermal holding furnace 5 are equipped with heaters 15, and the first zone has an additional eight heat transfer pipes 16 installed under the furnace roof and connected to the EMC 17 air duct with an electrified throttle valve 18 and a fan 19.

The isothermal annealing line operates as follows. In the heating furnace 1, the parts are heated on pallets 2 to a temperature of 900-940 C. The pallets 2 in the furnace 1 are pushed by the followers 12 to the discharge end of the furnace. Conveyor 10 removes two pallets from oven 1 at the same time and transfers them to Kajviepy underpressure 3, where the parts are cooled from the surface to a temperature of 500-550 C for 5-7 minutes by blowing them with hot air at a temperature of 400-500 C, supplied by the recirculation system 4 The condimented pallets are pushed out of the support chamber 3 and conveyor 11 by the conveyor 10 into the isothermal holding furnace 5, which has a temperature in all zones of 600-620 C. Excess heat generated from the internal parts of the parts through heat-resistant pipes 16, anovlennyh in the first zone of the furnace is passed air blown by the fan 19 tepzhyubmennye povozduhoprovodam pipe 17. The number of blown air is regulated electrified throttle valve 18. The greater the excess heat pallets and items entered into the furnace, the more air is blown through the heat exchange tubes. On the contrary, when there is a lack of introduced heat, heaters 15 are automatically turned on to maintain the required temperature in the furnace.

SPECIFIC EXAMPLE OF ISOTHERMAL FURNACE FURNACE

The passage-type furnace includes 4 zones, all zones are equipped with heaters 15, evenly maintaining a temperature of 600-620 C. The first zone is cooling and sleep-filled with eight heat-exchange tubes 16 having an outer diameter of 121 mm, a length of 1600 mm, installed under the furnace arch in transverse direction in increments of 350 mm at a distance of 770 mm from the surface of the parts. The weight of the workpieces from 0.2 kg to 10.0 kg, the weight of the charge in the pan to 35 kg.

Thus, the equipment of the first zone of the isotherm oven with heat exchange by pipes ensures removal of excess heat from the furnace and maintaining the required temperature.

The advantage of the isothermal annealing line is the improvement of the quality of heat treatment, summer and the expansion of the range of heat-treated parts due to the installation of heat exchange tubes in the first zone of the furnace and thermal exposure.

Claims (1)

An isothermal annealing line, including a high-temperature heating furnace, a baking chamber, an isothermal holding furnace, connected by a push-type conveyor, characterized in that the isothermal holding furnace is divided into zones, of which the first zone is cooling and is equipped with heat exchange pipes connected to the fan via air ducts, and throttle.