SU742399A1 - Enamel slip - Google Patents

Description

The invention relates to the protection of steel products by glass enamels from acid corrosion and can be used in the enameling of large products (tanks, apparatus) using induction or kiln firing methods. To enamel large-sized products, mainly acid-resistant enamels are used, which are applied to the products along the ground. Economically and technologically more advantageous is the use of a soilless acid-resistant enamel that is wet applied directly to the metal. The enamel slip is known for non-soil acid-resistant enamel consisting of friggs, psha, chromium oxide, quartz sand, molybdenum anhydride, borax and water in the following ratio of components, oars. Frit100 Quartz sand15.0 Clay4.0 Molybdenum anhydride1.0 Chromium oxide1.0 Borax 0.2 Water 50.0 11. The disadvantage of this slurry composition is the need to use a high temperature (850 ° C) calcination and low acid resistance of the coating formed on its basis. The closest is an enamel slip containing, by weight, parts; Frit acid resistant 100 Quartz sand 10.0 Bentonite1.0 Molybdenum anhydride1.0 Chromium oxide1.0 Titanium dioxide 0.5 Borax 0.5 Sodium nitrite 0.1 Water 50 2. The known composition of the slip allows you to apply enamel coating by pouring and get a high-quality coating for induction firing . The disadvantage of this composition is the need to apply a high calcination temperature (830 ° C), the provision of which leads to significant (energy consumption. In this case, when enameling large-sized products using application heating, as a rule, there is not enough power induction installations at the required firing rate. The latter entails the appearance in the coating of defects, pores, bubbles, underflows,

The purpose of the invention is to reduce: the burning temperature of the enamel coating while maintaining the necessary properties of the slip.

This goal is achieved by the fact that an enamel slip containing an acid-resistant frit, sand, titanium dioxide, chromium oxide, molybdenum anhydride and water, additionally contains sodium fluorosilicate, dvuhromo-. ammonia, liquid glass with a specific weight of 1.40-1.41 g / cm and a module of 2.7-2.9 in the following ratio of components, weight.h Acid-resistant frit100.0

Sand 5-10,0

Titanium dioxide 0.5-1.0

Chromium oxide. 0.5-1 D)

Mol 1bdenovoy anhydride 0.5 to 1.0

Water45-55

Sodium fluorosilicate 0.1-1.0

Ammonium bichromate 0.1-1.0 liquid glass with specific weight of 1.40-1.41 g / cm and module 2.7-2.92.0-4.0

In order to obtain an enamel slip, all the components are loaded into a ball mill and once small enough to grind 0.7-1.1 ml according to Lysenko. The resulting slip is applied to the steel products, dried at .80-100 ° C and burned. The second cast layer is coated with the second layer, and so on. until the enamel coating thickness reaches the specified value.

When the specific gravity deviates from the indicated value, a corresponding recalculation of the quantity of liquid glass introduced on the grinding slip is made.

In tab. 1. presents the composition of the enamel slip.

Table 1

Acid-resistant Frit 5,07,5 TU26-01-449-72 Titanium Dioxide TU 6-10-1430-75 Quartz Sand 100100 TU 21-USSR526-70 0,50,75 Chrome Oxide, 50,75 Molybdenum Anhydride TU 4806-4 -68 Sodium silicofluoride GOST Ammonium dvuhromovokisly GOST 3763-64 Liquid glass with a specific weight of 1.40-1.41 g / cm and 2.7-2.9 2.03.0 GOST 8264-56 4550 0.75 5.07 , 5 10 1,00,50,75 1,0 100 100 100 100 0,751.0 1,00,5 0,751,0 1,00,5 0,51,0 1,00,1 0,51,0 1,00, 1 4,02,03,0 4,0 555550 45 As a Frit for 1-3 compounds, Fretta is used, containing, wt.%: SiOi - 58,08; AljOs - 2.65; CaO — 2.40; NajO - KjO - 2.70; Li, O - 3.90; BjOj - 4.40; TiOj - 2.10; CaFj - 4.15; COjOj - 0.71; NijOs - 0.74; SrO - 1.50; NajSiFj - 3,36, a for 4-6 compositions Frit, containing, wt.%: SIOi - 71,48; - 2.54; CaO 4.33; NajO - 6.41; K, O - 5.42; LijO - 4.53; Ty, - 4,44; COjOj - 0.38; NijOj - 0.17. In tab. 2 presents the properties of the described compositions of enamel uumcqia. table 2

Claims (1)

The claims 40 An enamel slip, including acid-resistant frit, sand, titanium dioxide, chromium oxide, molybdenum anhydride and water, characterized in that, in order to reduce the firing temperature, it additionally contains sodium silicofluoride, ammonium dichromate, liquid glass with specific gravity 1.40-1.41 g / cm ³ and a module of 2.7-2.9 in the following ratio of components, in parts by weight: Acid Resistant Frit100 Sand 5-10 Titanium dioxide 0.5-1.0 Chromium oxide 0.5-1.0 Molybdenum anhydride 0.5-1.0 Water45–55 Sodium silicofluoride 0.1-1.0 Ammonium dichromate 0.1-1.0. Liquid glass, with a specific gravity of 1.40-1.41 g / cm ³ and a module of 2.7-2.9. '2.0-4.0