CS263384B1 - A method for removing grease and dirt from the surface of a wire - Google Patents

Abstract

The aim is to provide a clean, water-wettable surface, especially a steel wire drawn or cold-rolled to form a suitable substrate for the application of a bare paint system. By interacting with an aqueous solution of dimethyl diamine diamine tetraacetic acid, alkali carbonates, surfactant and vibration or ultrasound, the desired effect is achieved without the need to separate the individual threads of the coil in the coil prior to the purification process and be substantially faster than the conventional techniques used. degreasing of metal surfaces.

Description

263384 2

BACKGROUND OF THE INVENTION The present invention relates to the removal of lubricants and impurities, in particular, from the surface of a wire drawn or cold rolled steel wire, or articles thereof, used to reinforce porous concrete parts. Nowadays, mainly hot-rolled grade 10 216 steel is used to produce aerated concrete reinforcements. Prior to the application of corrosion protection on the basis of paints, it is necessary to clean the surface of steel or reinforcement with the necessary surface of steel or reinforcement. Continuous mechanical cleaning is not reliably resolved throughout the range of manufactured and used steels.

There is no suitable chemical cleaning of steel.

Pickling of finished welded networks in inorganic acids does not allow ČSN 03 8221.

The technical and economic demands of ensuring steel cleanliness of 10 216 prior to the application of corrosion protection of porous concrete reinforcements prompted the replacement of this steel with 11 373 cold drawn steel. The surface of this steel is virtually free of scaling and corrosive fumes.

It is based on hot-rolled steel 11 373. However, after cold drawing, the surface is contaminated with calcium hydroxide, calcium carbonate, calcium soaps (a mixture of stearate, oleate and calcium palmitate), alkaline soap and, in particular, unidentifiable purities. These substances form a dense, hardly removable hydrophobic layer on the steel surface.

Because water-soluble dispersion paints are used to counteract corrosion protection of aerated concrete reinforcements, it is necessary to provide water-soaking of the steel surface. Commonly used methods of hydrophilization are not sufficiently effective and fast for these purposes.

These disadvantages are eliminated by the method of removing lubricants and impurities from cold-rolled steel by a continuous or discontinuous method according to the invention, which consists in immersing the wire in an aqueous solution of composition: 0.50 to 15.00% by weight. dimethyldiaminotetraacetic acid sodium salt (C Q QH ^Og ^ Na Na), 0.10 to 10.00% wt. Sodium bis-2-ethylhexylsulphosuccinate <2H20O7N2 'is vibrated at a frequency range of 5 to 60 Hz with an effective acceleration value of 10 to 60 nts'2, or an ultrasonic frequency field! 18 to 50 Hz.

In the wire cleaning of the wire in a discontinuous manner, 50 to 100 [deg.] C. for 10 minutes to 2 hours and effective vibration are treated with the above solutions.

With continuous purification of the wire in solution of the same composition, it is caused by an ultrasonic field at 50 to 90 ° C and a drift rate of 0.25 to 2.0 ms ms1. The combination of these factors makes the entire surface of the wire available in a loose coil for chemical solution solution, effectively disrupting the hydrophobic layer of grease and impurities, removing it from the surface of the wire and dispersing it in solution. After subsequent rinsing with water and drying with hot air, the surface of the steel and mechanical and chemical impurities is wetted with water in accordance with the requirements of ČSN 73 1343. Examples of using the method of removing grease and dirt from the surface of the cold drawn wire are shown in the accompanying drawings where in the vertical direction and in the image 1b in the horizontal direction for the discontinuous cleaning process and in the images 2a, 2b, the use of ultrasound in continuous process cleaning is shown. Example 1

The procedure for removing greases and impurities causing hydrophobicity of the steel surface, viz. la, lb.

The loose coil of cold drawn steel 11 373 is deposited on the coil carrier 2, which is placed in a bag 3 filled with an aqueous composition of 0.50 to 15.00% by weight. sodium salt

Claims (1)

OBJECT OF THE INVENTION Method of removing grease and dirt from the surface of a cold drawn wire by a continuous or discontinuous process, characterized in that it is immersed in the aqueous solution of a composition of 0.50 to 15.00 wt. sodium dimetyldiamínotetraoctovej of ^<c i () ^H I 2 ^O 8 ^S 2 ^For 4 &quot; from 0.10 to 10.00% by weight. sodium bis-2-ethyl-hexylsulfosuccinate ( ^c 12 ^H 20 ^O 7 ^N 2 ') is vibrated in the frequency range 5 to 60 Hz with an effective acceleration value of 10 to 60 ms ² , or an ultrasonic field at a frequency of 18 to 50 kHz.