The foundry of Seco Industries, s.r.o., which is a Czech company, boasts with more than a century of tradition in the production of ductile and gray cast iron castings. Ductile iron castings are cast in sand molds. The gray iron foundry is focused on the production of cylinder liners for diesel engines. They are centrifugally cast into shell linings. The technologies of metal melting and subsequent casting are completely independent of each other in both operations, as well as in the entire process of cooling, finishing, final inspection and subsequent dispatch.

Currently, our foundry produces castings for major multinational companies operating worldwide. The foundry produces small castings, used in the automotive field. They are designed for compressors and camshafts of internal combustion engines. We produce castings for large-scale production of simple and complicated shapes in the weight category of 0.1 to 3 kg. We have a separate division for the production of cylinder liners.

• automotive industry
• railway industry
• construction
• agricultural machinery
• other sectors

The charge consisting of a cast iron door, steel scrap, crude iron and alloys is placed in the furnaces by means of vibrating loading trolleys. After melting, correction and inspection of the chemical composition, the metal is poured into a modification ladle. The shape of the ladle guarantees the ideal use of magnesium for modification in the production of ductile iron.

After the modification, the slag is removed from the surface and the metal is poured into an automatic casting machine, which casts the metal into molds from a uniform bentonite mixture at a high rate. Inoculation of the the metal stream ensures the correct structure of ductile iron after casting, ie the formation of spheroidal graphite during solidification of the metal, eliminates the effect of inoculum fading and minimizes the necessary amount of inoculum per 1 kg of cast metal. After casting, the inlet systém castings cool on the conveyors at the end of which the molds are broken on a vibrating grate so that the inlet systems are separated from the sand mold. After the castings have cooled, the parts are blasted for the first time from the remnants of sand adhering to their surface and are separated from their inlet system. The castings are blasted and ground a second time to remove any dirt and surface defects.

This makes the casting ready for packaging and subsequent shipment. In Seco Industries, s.r.o. we also offer machining of castings in our machining shop, which is part of the company’s premises.

Casting production process

0,1 to 3,0 kg

max 300 x 400 mm

from 1 000 pieces yearly

ductile iron

 Foundry and technology

Throughout its existence, Foundry Seco Industries, s.r.o., has strived to keep up with technological developments in the field of foundry. The peak is the installation of automatic molding machines and automatic casting machine. The entire production process of casting has thus undergone a complete modernization. This has enabled us to meet even the most demanding requirements of not only existing but also new potential customers.

Packaging of castings

Emphasis on operational and fast logistics has never been more justified than in today’s volatile world of trade and services. SECO INDUSTRIES, s.r.o. also offers a comprehensive logistics solution for the supply of castings and cylinder liners not only to the European market, but we also experience in distributions to North and South America and Asia. These packages can vary significantly. How? For example, environmentally friendly anti-corrosion protection of the surface of castings for overseas deliveries, where we also apply a moisture inhibitor to the packaging unit itself.

For packaging for customers in Europe, we use, among other, multi-layer cardboard boxes with liners and custom-made liners, which prevent movement during transport and damage to castings, while meeting the requirements for automatic handling and unloading on the customer’s line. Wooden crates, in turn, meet customer requirements for the supply of cylinder liners for internal combustion engines. These are just some examples of packaging of castings and cylinder liners in SECO INDUSTRIES, s.r.o., but we can also adapt to individual customer requirements. By fulfilling the standards according to IATF 16949: 2016, we are flexible for changes in the terms and composition of shipped products.

Foundry Seco Industries, s.r.o. and quality management

We are a purely Czech foundry. We have been trying to supply our customers with good quality castings for more than a hundred years. For this reason, we place great emphasis not only on maintaining the quality management system, but especially on its development in order to ensure the high quality of our castings. Seco Industries, s.r.o. meets the requirements of the international standard IATF 16949: 2016. It is intended for quality management systems in the field of automotive. IATF defines and at the same time expands the requirements for the ISO 9001 quality system, which is a standard for us.

For the general public, Seco Industries, s.r.o. is a foundry that casts in the sand. Of course, nothing is as simple as it may seem.

We do not cast in sand, but in a uniform bentonite mixture. It is a mixture of quartz slag, natrified (activated) mixed bentonite and water. Bentonite is simply clay. Clay containing more than 80% of montmorillonite (a three-layer mineral). The property of bentonite is a high ability to swell when mixed with water, this ability is further increased by natrification. Mixed bentonite contains carbon, which causes the formation of shiny carbon after casting the mold with metal. This is especially important for smooth casting surfaces and to prevent sticking.

The bentonite we use is mixed from raw materials from the surroundings of Most and from Slovakia. Each bearing gives bentonite the right properties (strength, heat resistance).

The input to our wheel mixers is returnable sand, new sand, bentonite and water. From these components we mix a uniform mixture (hence uniform bentonite mixture), which has the same composition in its entire volume. We discharge about 1 ton of mixture from our mixers in 5 minutes so that we can supply our molding lines.

We mold on automatic machines that make vertically divided frameless molds. After casting, the metal in the mold cools on the conveyor.

Production and testing of molds

The mold arrives on the vibrating grate, where it is broken using vibrations. Most of the sand falls underground, lumps are crushed by wheels and this sand is transported to a large-capacity container by means of a conveyor. From the large-capacity tank, the mixture is transported to a sand cooler so that the sand temperature is as low as possible. Then the sand is transported again to the hopper of the wheel mixer. It takes about 1 hour for the sand to pass through the entire foundry system. Only the sand, which is in close proximity to the inlet system and the casting, goes to waste, as the bentonite has passed the dehydroxilization temperature and becomes a fireclay putty that covers the slag grains. Then this slag can no longer be used in a uniform bentonite mixture, as we would unnecessarily increase the amount of water required and the grain would no longer be coated with active bentonite.

The production of a uniform bentonite mixture is a complicated matter. A uniform bentonite mixture has ideal properties only in a certain narrow ratio of all components. The properties of the mixture are evaluated daily in our sand laboratory by tests such as compressive strength, shear strength, agglomeration, moisture, breathability, amount of combustible substances, active bentonite content, sieve analysis, etc.

Based on long-term statistics, the mixture is controlled by our experienced staff so that it has the most stable properties and allows castings of the highest surface quality.

Casting in the foundry

Casting in the foundry is done on an automatic casting machine with a siphon ladle. The device automatically moves along the entire length of the casting field and, based on the data from the forming machine, moves exactly over the inlet wells. The molding machine transmits the casting data to the casting machine.

Each recipe in the casting machine contains data on the required casting weight, casting time, inoculum amount, etc. Based on data such as the weight of the metal in the ladle, the metal stream leaving the ladle and the metal level in the casting well, the casting process itself is controlled.

The biggest advantage of this casting technology is the automatic inoculation into the metal stream and thus the reduction of possible human errors, high productivity without time loss for large-scale production of ductile iron castings on the DISAMATIC 2110 MK molding line. Increasing safety in the workplace should also be mentioned. By inoculation into a metal stream, we are able to achieve high quality of produced castings (without cementite with a fine structure) with a minimum of inoculant. The advantage of the siphon ladle lies in the simple change of the cast material, ie during operation to change the class of cast ductile iron without affecting the performance of the foundry. We cast all common classes of ductile iron on the machine according to ČSN EN 1563 / GJS-400-15, GJS-500-7, GJS-600-3, GJS-700-2 and their modifications.