DE4121169A1 - Concasting of grinding balls for cement industry - using high alloy grey cast iron@ poured into constantly assembled and disassembled mould halves passing around closed circuit chain drive - Google Patents

Abstract

Starting material of grey cast iron contg. a high amt. of alloying elements is poured into two part moulds (2) which are assembled and disassembled at the top and bottom respectively of the concasting section (4) by rotating pistons (6) with magnetic holding plates (7). The formed concasting at the bottom is sepd. into balls by shear cutter (11). USE/ADVANTAGE - Producing grinding balls of 20-90 mm dia. The balls produced have good wear resistance and do not have to be heat treated. The method reduces the production costs by avoiding constant mould production, and eliminating a lot of transport. Cleaning costs are also reduced or eliminated.

Description

Title: Process for the continuous production of high wear-resistant grinding balls primarily for the cement industry in permanent forms according to the continuous casting principle

It is known to have spherical grinding media in diameter range 20-90 mm for the cement industry for inclusion in Cement drum mills with a maximum iron abrasion of To produce 35-50 grams per ton of regrind by casting. State of the art is still the pouring of the liquid Metal for the manufacture of the grinding balls mainly in high pressure-pressed molds on Disamatic molding lines 2013. Thereby it is a boxless and vertically divided High pressure press molding process with machining consequences

• - molding material preparation,
• - Disamatic mold making,
• - Automatic pouring over unpacking drum, unpacking, cooling, Separation, sprue-riser system, separation of the balls from each other,
• - Heat treatment with tunnel tunnel kiln.

Belgian and Japanese are market leaders in this area Companies. The production of meal is also known balls in the normal green sand process and to a small extent also in metal molds (molds).

Mainly high-alloy gray cast iron Materials GG (Cr, Mo, Ni, Mn and Cu alloy) are used. Subsequent heat treatment makes it homogeneous Structure reached. This will cause the chip to flake or break Prevents balls and ensures even wear accomplishes.

The manufacturing processes described require costs intensive measures

• - for the production of molding materials, compression of molding materials, trans port and emptying.  
• - for the casting of high-alloy GG feed materials with subsequent heat treatment.

The invention specified in claim 1 is the problem the bottom, by pouring grinding balls (ball to ball with mutual feeding) in the continuous casting process

• - to reduce manufacturing costs,
• - Same or also with the use of cheaper material to achieve better wear properties,
• - Significantly reduce the heat treatment required or switch off completely,
• - Eliminate the cleaning effort completely or significantly reduce it.

The internationally required grinding balls in a highly productive continuous casting process or Manufacturing discontinuously in permanent forms is essential Lich to reduce energy consumption and environmental pollution at.

An advantageous embodiment of the invention is in the claim 2-7 specified. The training according to claim 2-7 he makes it possible by using specially trained permanent forms Balls as grinding ball strand continuously in series production to manufacture.

In claim 8, a casting of 2 to more grinding balls in discontinuous strands in one or more souls represented per permanent form, mold or green sand process.

Embodiments of the invention for the manufacture of the Grinding ball strands are:

• 1. Continuous continuous casting according to FIG. 1.
• In group or single molds on a mold casting machine or carousel clocked vertically to horizontally are ordered
• - preparing the individual or group form,
• - Shut down,
• - Pour in a vertical cycle of groups or singles shape via weighing pre-dosing falling or rising (with Low pressure),  
• - cooling cycle,
• - To open,
• - return of the permanent form to the input measure,
• - preparing the permanent form,
• - Continuous separation of the grinding balls from the strand.
• 2. Discontinuous strands according to FIG. 2.
• Be on a mold closing machine or carousel one or more permanent forms arranged horizontally to vertical in the bars
• - preparation of the permanent form (preheating, coating),
• - Shut down,
• - pouring off every single permanent mold,
• - Cooling down,
• - To open,
• - ejecting the spherical strands,
• - Prepare the mold or permanent mold for the next cycle
• - Separate the grinding ball strands (shear).

The same strands can also come in different shapes be produced or cast using the green sand method.

Claims (8)

1. A process for the continuous production of highly wear-resistant grinding balls primarily for the cement industry in permanent molds according to the continuous casting principle, characterized in that a liquid melt from the material qualities GGG and GT is cast in a continuous or discontinuous cycle to form a strand ( 1 ) in a permanent mold according to the continuous casting method becomes. 2. The method according to claim 1, characterized, that the permanent form made of metal, ceramic or chemically bound Can be made of materials or from a metal mold with ceramic or chemical lining. 3. The method according to claim 2, characterized in that depending on the ball diameter of the permanent mold strand from several individual molds or permanent molds with a ball or 2 ball halves ( 2 ) can be assembled or already two or more balls in a permanent mold strand or in a mold are arranged in a strand. 4. The method according to claim 3, characterized in that depending on the ball diameter of the permanent mold or mold strand is thus guided and clocked by one or more ball diameters vertically to horizontally via a double chain drive ( 3 ) in a strand mold ( 4 ) and in the same One or more balls can be shed at the same time. 5. The method according to claim 4, characterized in that with the clocking at the end of the strand, the permanent molds or molds are opened again and a hydraulic turnstile ( 5 ) with 4 pistons ( 6 ) and 4 magnetic clamping plates ( 7 ) the opened mold or Permanent mold halves ( 8 ) are clocked back to the closed position again to the left and right of the main strand via a strand mold ( 9 ), each operated by the 2 chains ( 3 ). 6. The method according to claim 5, characterized in that before the closing ( 10 ) (analogous to opening the mold or permanent mold) the surfaces of the mold or permanent mold parts are cleaned, checked and provided with a coating or lining and preheated if necessary can. 7. The method according to claim 6, characterized in that after opening the mold, the exposed grinding ball strand is immediately separated by a holding and shearing device ( 11 ) ball by ball and, as required, the hot balls collected in a closed chamber, cooling or a necessary heat treatment. 8. The method according to claim 1, characterized, that the grinding balls also outside of this continuous Strands in discontinuous strands depending on the ball diameter with one or more souls (strands) in one Permanent form, mold or green sand process vertical to horizontal can be shed. The opening and Hydraulically closing the molds or permanent molds in individual machines or on mold carousels with several casting, Cooling, ejection and preparation stations or mold stations or in the green sand process in different mold boxes or Shaped bales.