Menu

machine

2150038862

Why Decentralised Automation?

, , , , 0

 

What does the skipper do on a racing yacht? The traditional view of a seafaring captain or skipper is that of one person who makes every tactical and operational decision and who then issues commands to the crew to make it happen. On a racing yacht there simply is not time for all that rigmarole. Each member of the crew has specific functions they perform, and they have trained as a group to work in precise harmony to achieve their common goal using their individual areas of expertise. In these terms, traditional centralised automation is the skipper standing on the quarterdeck (control room) while decentralised automation is the racing yacht where all the crew members (machine modules) perform their functions quickly and efficiently in perfect synchronisation. So, how does decentralised automation work in heavy steel fabrication companies? Let us find out further in this blog.

Rationale for Decentralised Automation

Traditionally, automation systems had rigid hierarchies that were based around centralised control, as per the well-known automation pyramid diagram. The sensors and actuators were always connected to the PLC (Programmable Logic Controller). The PLC was always connected to some other system and so it went. Unfortunately, this well entrenched automation model can be limiting. It requires lengthy decision-making paths, and it also ties all the automation together to a single, central point. This means that a single fault or maintenance activity can bring an entire plant to a halt. As technology has advanced, the previously rigid levels have had to become more flexible. We now have sensors that detect machine wear, RFID (radio frequency identification) tags that tell the machine it is correctly configured for heat induction bending services and what it must do, and I/O modules that can decide independently to operate an actuator. It is no longer possible to place the present and future of automation within the constraints of a traditional automation system because it is simply not able to deal efficiently with all the extra capabilities that are now achievable.

Benefits of Decentralised Automation

Decentralised automation lays the foundation for a new era of automation. It enables maximum flexibility, and it creates numerous benefits such as:

Fast and easy commissioning – Each different machine, or each individual module is capable of fully independent operation.  They can be pretested before installation and issues with one section will not delay the progress of other sections. Wiring is easy thanks to IP67 components and standard industrial quick connectors. Control cabinets can be scaled down or eliminated altogether so that significantly less wiring is required.

Lower machine costs – There is a significant reduction in the necessary central control capacities. By reusing existing modules design costs are also reduced and the reduced wiring and mechanical requirements mean lower personnel costs (such as automation of tube bending).

Higher machine availability – There is a significant reduction in the risk of failure because decentralised automation has a much lower dependency on a central control system. A good example of this is factory automation driven by electromechanical cylinders. On-site machine condition monitoring allows early intervention when issues are detected before failure occurs. Module replacements in the event of a failure are fast, simple and require minimal configuration.

Short time-to-market – Decentralised automation allows users to respond dynamically to changing requirements. They can fine tune their equipment and process, even during production. Decentralised logic enables the testing of machinery and machine modules offline before delivery.  By reusing existing modules, the design phase is shortened.

Closing Thoughts

Decentralisation may not be perfect for every situation, but in most cases, it reduces wiring and hardware and cuts design time. It also reduces manufacturing and installation time, improves efficiency, and minimises downtime. As demonstrated with the racing yacht, having a single central control is often less efficient than having a well-trained and coordinated team of experts on the job. Centralised automation? It looks a lot like that outdated ship has sailed!

Jeweler processing metal bar

Tipping and Bowing of Metal Parts

, , , , 0

 

It is well-known that the primary cutting operation at most metal fabricators is performed by the fiber laser. This has made steel laser cutting very productive – until a part tips and causes a head to stop or crash. This can harm the productivity and cosmetic value of metal forming and increase the expenditure required to create the final product. This blog will look to explore this topic in more detail and also cover the subject of tabbing.

Reasons for Tip and Bow

Years ago, many machine providers and software vendors focused on transitioning operators from punch presses to the flying-optic lasers. Because the punch moves the sheet, everything needs to be tabbed in place, at least until they are evacuated down a chute or lifted by suction cups on an automated part removal system. Otherwise, parts do not fall out of a nest until operators snap or shake them out. When shops jumped to the flying optic lasers, sheets no longer moved, and many parts that were punched with microtabs no longer needed them. Of course, such lasers introduced a new variable: the slat position.

Slats generally are placed 2 to 3 inches apart, depending on the model of the machine. So, if a part (or slug from an internal feature) has at least one dimension less than 6 inches, it has the potential to tip. Most slats consist of tips or “teeth” that support the work. Certain part geometries could end up tipping into the “V” of the slat. Smaller parts can tip, but larger parts—especially those that are long and thin—can bow upward and throw a wrench into process stability of products such as pressure vessels. Material touted as being “laser flat” ideally should have equalized stresses such that, when a part is cut in the optimal way (to control the effects of heat, for instance), it does not bow.

Ripple Effects of Tabbing

These days, software can automatically detect and rotate parts so that the longest dimension is oriented perpendicular to the slats. Programmers also can set different tabbing strategies for different part sizes; a very small part might require just one tab, while larger parts up to a certain dimension require progressively more. Beyond a certain dimension, software will not place any tab at all. Tab placement can vary depending on the job requirements and the best practices at a particular structural steel fabrication company. For instance, some operations might choose to tab parts directly on the corners, while others prefer tabs on straight edges and, if a corner needs something for stability, a tab can be put several thousands of an inch away from the actual corner. It all depends on what benefits downstream operations and the part’s ultimate fit and function. Tab geometry can change depending on material thickness and grade, but it can also change based on what operations a part will undergo downstream. Those tab geometries affect how they break away from the part. At the laser offloading area, operators might shake parts out of a nest before running them through a flat-part deburring machine. Microtabs typically leave a burr on the part and a divot in the skeleton. This assumes that a fabricator will want to deburr the piece to create a perfectly flat edge.

Closing Statement

It needs to be understood that every machine part does not need a perfectly flat edge. For edges hidden within an assembly or covered by a weld, shops might choose to skip deburring and send the parts directly to forming. This may help in ensuring that parts do not form tips and bows, however that would also depend on other variables like the cut path strategy, nesting etc. In essence, it is possible to manage material from forming tips and bows – however there needs to be a greater understanding of the laser cutting process to manage this phenomenon.

Gears from an old industrial machine

Failure of Grease (and the Oil in it)

, , , , 0

 

Greasing is an age-old practice of lubricating machinery (usually made from metal) with oil. The oil is a thickener which acts much like a sponge. The purpose of greasing is to ensure that metal parts do not rust and that they operate smoothly in different weather conditions. However, greasing is not a foolproof method of lubrication and it may fail in certain cases. This is mostly due to the build-up of contaminants in grease which will hinder proper functioning of machinery. This will also lead to degraded quality of products, increased operational costs and a greater rate of depreciation of plant and machinery. So, how does grease and the oil fail? Let us explore further in this blog.

Oil Oxidation

Oil degradation caused by oxidation, which results in a permanent change to the oil molecules, will mean more frequent re-lubrication is required to replace both the degraded grease and any contaminants which the oxidation has created. The main cause of oxidation is elevated temperatures.  Generally, the rate of oil oxidation doubles for every 150C above 700C.  Therefore, the life of the oil (and hence the grease) is halved for every 150C rise above 700C. Degraded oils break down into by-products of the reaction that are harmful to bearings in steel fabrication. These include carboxylic acids which will corrode surfaces if left in the system and sludge and varnish will form over time. Higher temperatures also increase the rate of oil evaporation and bleeding from the thickener, which reduces the lubrication properties of the grease.

Additive Loss And Other Reasons

Metal fabrication has application in multiple industries, including oil and gas where lubricants are used. Additives that enhance the lubrication properties of the oil such as friction modifiers, corrosion inhibitors, anti-wear agents, oxidation inhibitors, EP improvers and adhesion improvers have a finite life and become depleted in use.  Once this occurs the grease and the oil in it can no longer perform to its original specification. Other factors which reduce the grease and oil life and therefore the re-lubrication interval is: –

  • Dust.
  • Materials and by-products created by wear and lubricant degradation.
  • Humidity and condensation (daily or operational temperature cycles will cause the air trapped in the housing to become a condensate) – an example is mining and plant equipment which is exposed to a humid environment.
  • Water and process-related liquids – The limit for the absolute water content in mineral oil – the lubrication component of most greases – above which problems will occur, is 200 ppm.
  • Vibration – high vibration will cause the grease to churn which will cause a grease life reduction. Vibration will also cause the grease to bleed more than normally, resulting in an increase in the hardness of the grease, limiting its ability to correctly lubricate rolling contact bearings.
  • Strong air flow or reduced air flow through the bearing (drying of grease, oxidation, removal of microscopic oil droplets).

The above factors will each cause a grease life reduction factor of between 0.4-0.7 times the normal grease life in a single row spherical roller bearing.  The reductions are cumulative for each cause and are in addition to the effect of temperature on the grease.

Final Thoughts

There are ways and means to protect against the reduction of grease and oil life. Continuous lubrication is the best preventative method to protect against the build-up of contaminated or degraded grease.  If contaminants have built up in the housing, then to fully remove them the housing must be opened and the bearings and housing thoroughly cleaned.  An alternative is to purge the housing however whilst that may remove most of the contaminants it is unlikely to fully remove them all.  If the contaminants are not removed then the bearing life will be decreased – hence it is essential that the road to operational efficiency is “well-greased”!

Ball bearing stainless with grease lithium machinery lubrication

Advantages of Clean Lubricants and Bearings

, , , , , , 0

 

The importance of bearing and lubricant cleanliness is perhaps self-evident, yet too little attention is paid to this critical quality. Even when small particles of foreign matter are not actually causing failure, they can ruin the bearing’s smooth-running qualities and low torque values – which, again, means higher energy bills and a less competitive plant. The results of poor maintenance and dirty bearings is lack of productivity, plant down-time, increased safety hazards, and unnecessarily high energy costs.  This avoidable failure creates costs that cannot be ignored in an increasingly competitive world.

Types of Contaminants

According to a major bearing producer, a particle of 5 microns – 5 µm — or less can cause a precision bearing to fail. To put this into perspective a human hair averages about 100 µm; coal dust 1-100µm, iron dust 4-20µm, atmospheric dust up to 30µm, combustion-related particulates from industrial processes up to 2.5µm and tobacco smoke up to 4µm. In general terms, dirt and contaminants that can impede a bearing’s performance are divided into three main categories:

  • Airborne contaminants: industrial smoke and dust, metal flakes, abrasive flakes, lint etc. which might enter the bearing due to poor storage and/or workshop practices.
  • Transferred contaminants: dirt that is picked up from one source and passed along to the bearing from hands, work surfaces, packaging, water tanks, poorly managed grease packing during assembly, grease degraded by moisture (condensation in the container and/or housing) and contaminants such as fumes and smoke.
  • Introduced dirt: impurities that enter the bearings from dirty lubricants or can be forced into the bearing during re-lubrication by contaminated equipment or grease points not thoroughly cleaned.

These sources of contamination should all be considered abrasive, corrosive, or leading causes of degradation of bearing performance and are all avoidable.

Merits of Clean Lubrication

Cleanliness should extend beyond the bearings themselves to work and storage areas, benches, tools, fixtures, and housings.  Bearing installation operations should be located away from other machining operations, such as grinding and drilling etc. to help minimise contamination problems. Selection of right lubricants leads to increased sustainability in metal manufacturing and poor lubrication practices are a leading cause of contamination.  Unsealed containers are susceptible to contamination from solids and from water due to condensation.  Once a grease container is opened, it is susceptible to oxidisation and water contamination which results from condensation caused by daily temperature cycles and from storage in humid conditions.  Oxidisation and condensation also occur the same way inside bearing housing.

Strict attention needs to be paid to cleanliness during grease transfers from bulk supplies to greasing apparatus, and to the application of greasing equipment to grease points.  Due to the nature of site conditions and the task itself, careful cleaning of grease points prior to greasing is frequently either not carried out properly, or at all. Static charges caused by friction in heat induction bending services can cause bearing currents which in turn can cause the steel rings and balls of the bearings to become magnetised, which worsens the problem of fine metallic particles introduced into the bearing as they will tend to stay there. Electrolytic action is present in most bearings where it is possible for the bearing and journal to act as electrodes, and where, due to some electrical phenomena, a difference of potential exists between them. A clean lubricant oil film acts as an insulator but impurities are the main cause of conductivity.  Clean, uncontaminated lubricant oil cannot act as an electrolyte: the presence of water or other foreign matter will initiate electrolytic action of the oil in the grease, which will shorten the life of the bearing.

Final Words

There are multiple advantages to having clean lubrication and bearings, especially considering the operations floor is vulnerable to different types of contamination. In the long run, equipment malfunction or degeneration is likely to occur in the absence of proper maintenance and this would require machine turnover at an advanced rate. Thus, in the manufacturing industry, clean lubricants and bearings go a long way towards ensuring increased productivity and lower costs!

cnc-turret-punch-press-machine-2021-08-26-16-53-47-utc (1)

Utility of Punch Press Machine

, , , , 0

 

Punch presses are one of several equipment used by manufacturers and heavy steel fabrication companies to manipulate and convert raw materials into finished products. Making uniform shapes out of raw material in large quantities is much easier with the use of punch presses. A punch press may be used by a company if a specific raw material is too difficult to cut manually since it cuts through metal and other hard materials with ease, creating holes that match the die form of the punch press. So, what are the applications and utilities of punch presses? This blog will look to explore this topic in further details.

Types and Applications of Punch Press

Similar to press brake machines, punch presses are used in stamping, punching, bending, shearing, converting, and assembly operations. They differ in terms of drive type and automation. Air-driven punch presses are powered by a pneumatic cylinder and are suitable for light-duty applications. Hydraulic presses are powered by a fluid-filled cylinder and can generate extremely strong forces to form metals and other materials. Manual presses are driven by hand, or powered with manual force that is magnified by a screw, lever, or other mechanism. Mechanical punch presses are driven by a rotary motor and screw, toggle, or lever. By contrast, servo-controlled presses are driven directly by a servo motor. Some punch presses are controlled manually, using operator interface devices such as footswitches, pendants, or push button controls. Others include a computer numeric controller (CNC) or programmable logic controller (PLC). Punch presses that are programmed and controlled with a personal computer (PC) interface allow users to set and adjust parameters such as speed and applied load. Indexing machines are fully automatic and can load parts and adjust parameters without operator intervention.

Specifications of Punch Press

Important specifications for punch presses include operating force, rated capacity, production rate, and sheet capacity. Operating force is the maximum load required to cut or form parts during assembly. Rated capacity is the tons of pressure via pressure vessels that the slide or ram exerts at the bottom of the stroke while working within the range of the press. With mechanical punch presses, operating force is a function of the bending capacity of the main shaft. For all types of punch presses, production rate is the number of operations performed or units produced per unit of time. Typically, this amount is expressed as the number of strokes, hits, cut-outs, cycles, or hits per minute. Most manufacturers specify sheet capacity in terms of maximum thickness, working length, and working depth. Working length is the maximum sheet length (largest dimension, X) or working distance from right to lift that can be punched, formed, or converted. Working depth is the maximum sheet (smallest dimension, Y) or working depth from front to back that can be punched, formed, or converted.

Special Features of Punch Press

Punch presses are available with a variety of special features. Some machines include integral shearing capabilities or optional material feeders. Others include laser cutting or monitoring systems. Multi-station punch presses include rotary tools and turrets, progressive dies, transfer systems, or multi-tool die sits. Rotary punch presses index materials and allow operators to select an appropriate tool from the turret. Loading and stacking systems are complete manufacturing cells that often include material handling and degreasing subsystems. They provide sheet, part, and material handling.

Closing Thoughts

Punch presses have a multitude of applications and they are versatile in their use throughout industry. In fabrication, punch presses provide a viable alternative to metal cutting and can also provide a degree of automation with certain types of punch presses. Going forward, it can be safely concluded that punch presses will continue to “punch” above their weight in the metal work world!

press-brake-machine-2021-08-26-16-53-47-utc (1)

Utility of Press Brake Machine

, , , , 0

Metal fabricators in Australia may find that a press brake machine is an indispensable piece of equipment. It provides a multitude of benefits, including an enhanced capacity for complicated tasks, automation, improved tolerance, and an overall improvement in the effectiveness of the working environment. As a result, the press brake machine is ubiquitous in many fabrication projects and is preferred by fabricators. This blog will take a deeper dive into the nuts and bolts of this versatile tool and whether its fantastic reputation is well-deserved.

Working of Press Brake Machine

A press brake is a type of equipment that can carry out a variety of metal fabrication techniques, such as blanking, punching, and cutting, among others. Sheet metal components of bespoke and OEM design have been manufactured by various businesses using the equipment in question. The press brake is undeniably among the most useful devices utilized in producing goods at this time, and its history can be traced back to the 20th century.

Benefits of Press Brake Machine

  • Less Waste – Compared to other production methods, the press brake results in a significantly lower amount of waste material. This can be ascribed to the machine’s capability of bending, cutting, or curving sheet metal into precise pieces via heat induction bending services. Most press brake machines are computer numerically controlled, often known as CNC. This indicates that they are fully automated and that every design component must adhere to an efficient process. Because of this, there is a reduction in the amount of trash created. Because of this, operators can conduct press brake operations promptly and effectively. Additionally, it shortens the amount of time required for manufacturing and lowers the costs incurred by consumers. Post-processing the manufactured metal pieces are also required less often, thanks to this development.
  • Development of Complicated Designs – The production of sheet metal is crucial in virtually all manufacturing processes. As an illustration, construction organizations require fabrications to build rafters, beams, and other structural elements for the projects they are working on. Conveyor belts, weighing scales, mixers, and other critical pieces of food service equipment are all examples of the kinds of metal fabrications the food and beverage industry needs to produce. It is interesting to look back and see how far the press brake machine has come. It used to be equipped to bend metals into shape, but now it can generate far more complicated shapes. These days, press brakes come with interchangeable components, which enables heavy steel fabrication companies to conduct a wide variety of operations. Some examples of these operations include burring, coining, and bending.

 

  • Robotic Process Automation – Manual operation of a press brake machine is an option. However, this depends on the needs of the business. It is also possible for the task to be entirely or partially automated. This piece of machinery, regardless of how it is operated, is crucial for enhancing the precision of the components and reducing the costs associated with labour. Tasks that formerly required human intervention may now be carried out in a manner that is both quicker and more effective, thanks to the development of automation technology. This is a realizable goal because of the press brake’s capacity for construction.

Final Takeaways

A press brake machine may improve a company’s production process by speeding it up, reducing waste, creating intricate designs, and much more. Thanks to this technology, many businesses may now have the exact tools they require for their art.

© K999 Engineering & Construction Co. Ltd. 2023