Latest acquisitions include a second horizontal moulding machine, a rotary drum and an automated core making machine.
“When I joined the company in 2011, I was given a challenging task to improve productivity, improve quality, reduce costs and scrap rates in a foundry that was operating in the 19th century. This was especially so as the foundry had not made any major capital equipment investments since the 1980s and there was a reluctance to provide funds for expenditure on modern foundry manufacturing equipment,” explained Divisional Managing Director Ben Dyson.
Malleable Castings has recently installed a second HMF automated horizontal moulding machine. This machine has a workable moulding area of 460mm x 360mm x 150mm and the moulding rate is 40 to 60 boxes per hour
“The constant pursuit of new ways to boost efficiency, enhance productivity, improve casting quality and increase savings, while battling environmental concerns, seeking to improve overall working conditions and ensuring the employment of sufficient manpower and resources – and preferably all at the same time – is universal. Irrespective of foundry size, geography and market, they remain factors that all foundries can relate to and continuously try to optimise,” continued Dyson.
Even though Ben had begun to make inroads on costs and productivity with the investment in a new 3-ton medium frequency 1.5 megawatt furnace there was still a cautious resistance to invest further in the foundry due to declining economic activity. This culture changed when Malleable Castings was sold to Pillans Investments towards the beginning of 2017, making way for the implementation of a turnaround strategy. Pillans Investments is an investment holding company with investments in West Rand Engineering, Africa Thermal Insulations, Glen Fluid Transfer Solutions, Wilco Howard and Klambon Water, which is based in Sydney, Australia. Pillans is a 100% South African, 60.8% black owned investment company and the shareholders include Shalamuka Capital, RMB Corvest and Management.
The automated line is also equipped with a mould manipulator and conveyor system for easy handling of the moulds
“West Rand Engineering (WRE), one of the companies within the Pillans Investments Group, had for some time been one of our biggest customers. With a national emphasis on local procurement through enabling legislation and strategic designations to attain the goals of the industrial policy action plan (IPAP) picking up speed in South Africa, Malleable Castings became a viable option for Pillans Investments to purchase. Additionally, the company could secure its supply chain in line with the mining charter.”
West Rand Engineering manufactures and supplies mining consumables for use in underground hard rock mining applications. The company offers air/water gun valves, ball valves, blow guns, brass water valves, dirt traps, hose grip magnets, manifold with valves, screw down valves, self-closing taps, shower valves, throttle valves, water blasts, hose connections, screw type hose connections, hose clamps and hose menders, laterals, and claw couplings, manifolds, rock drill lubricators, air whistles, hopper couplings, rail adjusters, and rope pullers. It also provides snatch blocks used in scraping of ore in narrow stope mining for hard rock, gold, platinum and chrome mines, incline shaft rollers, mono rope tensioners, pineapple rollers, return wheels, rope pulleys, and urethane rollers, taper knock off bits for underground rock drilling. The company was founded in 1928 and is based in Krugersdorp, Gauteng.
Second HMF horizontal moulding machine
“The productivity, quality and cost improvements as a result of the first horizontal moulding line investment, which was installed in December 2017, drove us to investigate a further investment in this department. The aim is to reduce our reliance on and to ‘retire’ our existing 10 manual jolt squeeze moulding machines because the human involvement gives consistency and quality problems, as well as a decline in productivity levels.”
Cores in a mould on the new HMF automated horizontal moulding machine
“I took my time in deciding on which machinery to purchase and it was only after a few visits to international foundries, using a similar machine that I was looking for, that I decided on a HMF automated horizontal moulding machine. The automated hydraulically operated machine has been custom built to suit our needs and we have already reduced our scrap rates enormously with the consistent and reliable manufacture of green sand moulds. Productivity is also reaching record levels with between 40 to 60 moulds being manufactured in an hour.”
“The automated line is also equipped with a mould manipulator and conveyor system for easy handling of the moulds. The scope of our capabilities in terms of the castings weight range from 0.1 kilogram to 30 kilograms and for sizes our pattern plate dimensions are 460mm x 360mm x 150mm.”
Malleable Castings have also invested in a new HMF rotary drum machine that has the capability of processing 40 tons per hour, which was installed in December 2018. The drum diameter is 1.5m and it has a length of six metres
“The second HMF horizontal moulding machine has similar specifications and capacities to the first machine. The workable moulding area is 460mm x 360mm x 150mm and the moulding rate is 40 to 60 boxes per hour. Again the benefits in investing in this machine are consistent mould quality, reduced mould handling times and scrap issues, easy pattern change and significantly reduced labour intervention due to the automated mould handling line. In simple terms the machine is a one-man operation.”
“We will still keep our manual machines operational at this stage as it does not make economical sense to run small quantities on the automated lines.”
HMF rotary drum
“There are two finishing processes for handling high volumes of metal parts – vibratory machines and barrel tumblers.”
“We have chosen the rotary drum method as there is a huge reduction of dust in the foundry as the sand is removed from casting before exiting the drum and sufficient extraction is part of the design. Additionally, the return sand that is sent back to the sand reclamation plant is cooler and a significant amount of deburring of the casting has already taken place, including the sprue, thus greatly reducing additional manual labour in the knock off process. Furthermore, the rotary drum requires far less maintenance than traditional vibratory feeders.”
Malleable Castings have invested in a new Delin DL361 automatic core shooting machine and it is the company’s intention to invest in a second machine
“The HMF rotary drum machine that has the capability of processing 40 tons per hour, was installed in December 2018. The drum diameter is 1.5m and it has a length of six metres. The man hours that we are now saving are significant.”
Delin DL361 automatic core shooting machine
“The theme of tired equipment continued in the core shooting department. However, this has now changed with the installation of a fully automatic electrically heated shell core shooter with a core box size of 400mm x 250mm x 150mm, also in December 2018.”
“The core shooting process is now fully automated with automatic core ejection and mould turning down to release cores onto an automatically indexed conveyor. The machine, once set, only needs someone to trim and pack cores, reducing operator costs significantly. The electrical heating of the core box in an enclosed machine is also more efficient than the old type gas heated open machines.”
“It is our intention to install a second machine in this department and this will happen shortly. The tooling for this machine is also new.”
The core shooting process is now fully automated with automatic core ejection and mould turning down to release cores onto an automatically indexed conveyor. The machine, once set, only needs someone to trim and pack cores, reducing operator costs significantly. The electrical heating of the core box in an enclosed machine is also more efficient than the old type gas heated open machines
Malleable Castings have also upgraded their sand storage silo
“Our capacity depends on how many shifts we run but at the moment we are pouring 120 tons of metal a month and are confidently aiming to take this to 150 tons. Depending on orders we are supplying about 70 to 80% of this output to group companies. The synergy within the group has certainly been beneficial to us but we are not entirely reliant on it. In recent times we have acquired new clients in the mining, automotive and pump manufacturing industries.”
“The resultant gains from these capital equipment investments is measureable, especially if you are calculating on the number of boxes per head, per shift, per machine, as we do.”
“Going forward we are going to pay attention to our sand reclamation plant, which needs some more upgrades and improvements. Sand quality is vitally important in the green sand process. We will also be adding more melting capacity in the near future.”
For further details contact Malleable Castings on TEL: 011 822 1503 or visit www.malleable.co.za