CN1144787A

CN1144787A - One-step burning method for silicon-carbon bar cold-extruded formed belt end

Info

Publication number: CN1144787A
Application number: CN 95100397
Authority: CN
Inventors: 薛天瑞
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-02-16
Filing date: 1995-02-16
Publication date: 1997-03-12

Abstract

A process for one-pass burning cold extruded Si-C rod with end part includes such steps as mixing silicon carbide, graphite powder, carbon black, polyvinyl alcohol, dextrin and boric acid together to form heating part, mixing silicon carbide, graphite powder, carbon black, polyvinyl alcohol, silicon powder and boric acid together to form cold end part, then respectively extrusion shaping and baking them, after connecting them with water adhering faces, baking, immersion in asphalt and burning at 1800-1900 deg.C, and features uniform density and high qualified rate of product, short production period and low energy consumption.

Description

The method of the cold extrusion shaped strap end portion once-firing of a kind of globars

The present invention relates to the method for the cold extrusion shaped strap end portion once-firing of a kind of globars.

The production of the electrical heating element globars of domestic current all adopts pitch to do caking agent, its heating portion adopts steam or electrically heated, under greater than 200 ℃ temperature, carry out hot batch mixing, hot extrusion molding, be biscuiting and under greater than 1800 ℃ temperature, burning till for twice under 1000 ℃-1200 ℃ temperature then, its cold end is to do caking agent with resin, under 170 ℃-180 ℃ temperature, solidify, and will biscuiting under 1000 ℃-1200 ℃ temperature, be under 2300 ℃-2500 ℃ temperature, to carry out siliconising to handle then, again cold end carried out vacuum welding with the heating portion of burning till under 1800 ℃-1900 ℃ temperature.Whole technological process is fair long and complicated, power consumption is big, yield rate is low with regard to making like this, and product layering and crescent moon pore are serious.

The object of the present invention is to provide a kind of can be in producing the process of globars shortened process, significantly energy-conservation, enhance productivity and improve the method for the cold extrusion shaped strap end portion once-firing of a kind of globars of quality product.

The mode that the present invention realizes is to match material at first respectively, its heating portion is major ingredient with silicon carbide, wherein 80 purposes account for weight 20%, 120 purposes account for weight 30%, 180 purposes account for weight 50%, other batching genus adds, the part by weight that accounts for major ingredient respectively is that Graphite Powder 99 is that-150 orders account for 3%, carbon black accounts for 1%, polyvinyl alcohol accounts for 5%, dextrin accounts for 4%, boric acid accounts for 7.5%, and its cold end is major ingredient with silicon carbide, and wherein 80 purposes account for weight 40%, 120 purposes account for weight 20%, 180 purposes account for weight 40%, other batching genus adds, the part by weight that accounts for major ingredient respectively is that Graphite Powder 99 accounts for 6%, and carbon black accounts for 3%, and polyvinyl alcohol accounts for 6%, silica flour accounts for 40% for-250 orders, boric acid accounts for 6%, and the batch mixes with heating portion and cold end is even respectively then, dries under 40 ℃-50 ℃ temperature after the extrusion molding respectively, water bonding rod back baking place under 400 ℃-450 ℃ temperature is reacted the base substrate after baking place 1800 ℃-1900 ℃ temperature behind impregnate with bitumen is next time burnt till.

The invention has the advantages that it has adopted carries out the method that batch mixing, extrusion under vacuum, water green compact are taken over the baton under normal temperature condition, through low temperature baking place, impregnate with bitumen and once-firing are finished product with the green compact of strap end portion.Its product does not have layering, no crescent moon pore, and the density of product is very even, thereby has improved the quality of product and the yield rate of product, has shortened the production cycle effectively, has saved the consumption of the energy significantly.Make operation reduce to 13 roads by 52 original roads, production cycle was reduced to about 10 days by original 56 days, make integrated yield bring up to present 70-80% by original 20-30%, coal consumption is 0, it is original 1/3 that power consumption has only, and eliminated the pollution of coal smoke and NOISE ON ENVIRONMENT.In annual production is under the situation of 4,000,000 standards, and current technology needs about worker 400 people, and the inventive method only needs about 50 people, and production cost is reduced to has only 1/3 of original technology.

The present invention is further described with embodiment below:

The present invention adopts following method steps:

1. the batching of selecting materials: the batching of its heating portion is major ingredient with silicon carbide, wherein 80 purposes account for weight 20%, 120 purposes account for weight 30%, 180 purposes account for weight 50%, other batching genus adds, the part by weight that they account for major ingredient respectively is that Graphite Powder 99 is that-150 orders account for 3%, carbon black accounts for 1%, polyvinyl alcohol accounts for 5%, its polyvinyl alcohol: water=1: 4 is water-soluble, and dextrin accounts for 4%, boric acid accounts for 7.5%, its boric acid: water=1: 5 is water-soluble, and its cold end is major ingredient with silicon carbide, and wherein 80 purposes account for weight 40%, 120 purposes account for weight 20%, 180 purposes account for weight 40%, other batching genus adds, the part by weight that accounts for major ingredient respectively is that Graphite Powder 99 accounts for 6%, and carbon black accounts for 3%, and polyvinyl alcohol accounts for 6%, its polyvinyl alcohol: water=1: 4 is water-soluble, silica flour accounts for 40% for-250 orders, and boric acid accounts for 6%, its boric acid: water=1: 5 is water-soluble.

2. batch mixing: heating portion batching and cold end batching are mixed respectively.Adopt and earlier all siccatives to be inserted after mixer stirs, again with caking agent with water-soluble after the boric acid adding, stir at normal temperatures.

3. extrusion under vacuum: the extrusion under vacuum in extrusion machine with heating portion batch mixing and cold end batch mixing respectively at normal temperatures.

4. oven dry: the base substrate of extrusion molding under 40 ℃-50 ℃ temperature, is dried in drying shed.

5. take over the baton: the sticking face of water bonds together heating portion and cold end.

6. baking place: under 400 ℃-450 ℃ temperature, adopt box-type furnace, the base substrate with oven dry is taken over the baton buries reality with carbon granules and dries by the fire the place in the iron case, and the baking place time is 12-13 hour.

7. impregnate with bitumen: to the base substrate impregnate with bitumen after baking place.The bituminous temperature is 200 ℃-250 ℃.

8. burn till: in resistance furnace, adopt and bury the burning method under 1800 ℃-1900 ℃ temperature, through 21-22 hour once-firing.

Claims

1. the method for the cold extrusion shaped strap end portion once-firing of globars, it is characterized in that matching at first respectively material, its heating portion is major ingredient with silicon carbide, wherein 80 purposes account for weight 20%, 120 purposes account for weight 30%, 180 purposes account for weight 50%, other batching genus adds, the part by weight that accounts for major ingredient respectively is that Graphite Powder 99 is that-150 orders account for 3%, carbon black accounts for 1%, polyvinyl alcohol accounts for 5%, dextrin accounts for 4%, boric acid accounts for 7.5%, its cold end is major ingredient with silicon carbide, wherein 80 purposes account for weight 40%, 120 purposes account for weight 20%, 180 purposes account for weight 40%, other batching genus adds, the part by weight that accounts for major ingredient respectively is that Graphite Powder 99 accounts for 6%, carbon black accounts for 3%, polyvinyl alcohol accounts for 6%, silica flour accounts for 40% for-250 orders, boric acid accounts for 6%, and the batch mixes with heating portion and cold end is even respectively then, dries under 40 ℃-50 ℃ temperature after the extrusion molding respectively, baking place under 400 ℃-450 ℃ temperature after the sticking face of water is taken over the baton is burnt till the base substrate after baking place 1800 ℃-1900 ℃ temperature behind impregnate with bitumen next time.