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Valve specialist expands fire protection valve range

Lug Butterfly Valve Industrial valves, control valves, control systems and instrumentation supplier Inbal South Africa has extended its range of fire protection valves. The company is importing its new range of products from flow control products manufacturer Nibco in the US, and is now able to supply monitored butterfly valves, check valves, gate valves and indicator post valves. These valves are all factory mutual (FM) approved. FM approval is an international third-party certification and approval of commercial and industrial products, including fire protection and prevention equipment. The new Nibco butterfly valve has a wafer or lug style body, is able to accept internal or external switches, and is available in sizes from 50 mm to 300 mm. The check valve is also available in wafer style, with a rubber seat, and is spring actuated. The sizes range from 65 mm to 400 mm. The gate valves have an epoxy coated interior and exterior and come in sizes that range from 65 mm to 300 mm, with an outside screw and yoke on a non rising spindle. "To sell a trustworthy valve into the fire protection market at a competitive price, is our company's main objective," says Inbal's managing member John Lowman. The company has been supplying FM-approved Inbal deluge valves to the fire protection market in South Africa since 1995. Some of its bigger clients include industry giants such as Sasol, Eskom, Transnet pipelines, ArcelorMittal Steel, Total, and Anglo Gold. "The Inbal valves were specifically engineered for industrial fire protection systems and have proven to be very dependable in the market," says Lowman. He explains that each valve is fully tested on a large capacity hydraulic test rig controlled by a field control system. The test is carried out automatically with actual flow and pressure according to a predetermined procedure for each individual application and the information is monitored and recorded. The Inbal automatic control valve is a pressure-operated, sleeve- actuated valve designed from basic concepts, with a built-in actuator to function as a control valve in fire protection. The valve uses the no moving mechanical parts (NMMP) design, which ensures a longer life of dependable operation. The small physical dimensions and the low weight enable the valve and the control trim assembly to occupy much less space and significantly reduce the time and labour needed for installation. The Inbal valve can withstand pressure surges and is resistant to false tripping. The opening action of the valve is quick, yet smooth, eliminating water hammer. All the valves are rated at 21 bar, and are available in sizes from 40 mm to 300 mm. The Inbal valves are made of ductile iron, are epoxy coated and the control trim is made of stainless steel and nickel-chrome plated brass. The valves are designed to work with potable water and foam, and are also available in special materials for seawater. In addition to the above, Inbal South Africa has also extended its range of non-FM butterfly and wafer non return valves. The butterfly and non-return valves are wafer style, and have a cast iron body with a nickel-plated ductile iron or a stainless steel disc. The valves are rated at 16 bar. Inbal's executive member Christo Murphy estimates that the company's ex-stock supply is currently standing at more than one-million rand for the butterfly and check valves and in excess of five-million rand for the Inbal Deluge valves, which reduces the lead times considerably. He adds that the company has strong business relations with most of the South African valve manufacturers and uses the services of valve sourcing agents worldwide. These links enable the company to provide short lead times on all valve types irrespective of brand name, size, pressure rating or materials required. "The company is also able to provide excellent technical support to our clients whether it be telephonically or onsite," adds Lowman. Inbal South Africa is a Small Enterprise Employers of South Africa rated level two black economic-empowerment compliant company, its main offices are situated in Midrand.
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Why do patients go for homeopathy?

While medical texts published more than five years ago are typically considered outdated, old and antiquated publications often hold valuable insights into the development of treatments and into the presentation of diseases. This is exactly what Samuel Friedrich Hahnemann, MD, had in mind when he began translating medical texts in the late 18th century. Dr. Hahnemann had denounced the medicine of his time as irrational. His sentiments were likely well-founded, as blood-letting and calomel were standard treatments for everything from the common cold to combat wounds. The yellow oxide form of mercury was a panacea for chronic eye conditions, and ocular injection of cobra venom was used to treat macular degeneration. Needless to say, these treatments worsened the conditions or expedited death more often than they cured. Homeopathy—literally, “same suffering”—was Dr. Hahnemann’s solution to these wayward medical practices. As a result of his research, he proposed that an illness could be treated with a substance that caused symptoms similar to the illness in a healthy person. Serial dilution removed the toxic effects of the substance, while the “essence” of the substance was retained by the diluent. Homeopathy blossomed in popularity because while its efficacy was comparable to bloodletting, homeopathy didn’t cause further harm. Its popularity, however, was short-lived, as more scientific approaches to medicine became preferred. For almost a century, homeopathy remained quiet, virtually forgotten by all except so-called “quack” doctors. In recent decades, however, homeopathy has seen a revival, becoming a multi-million dollar industry serving at least million Americans. In our increasingly well-educated country where evidence of efficacy is expected, what is driving patients to trust in homeopathic remedies for ophthalmic conditions? Homeopathic History Today, quinine derivatives from cinchona bark are known to be a natural treatment for some forms of malaria, although fatal if taken in high doses. While translating documents involving its anti-malarial activity, Dr. Hahnemann decided to try the supposed-cure, and after repeatedly dosing himself, he experienced symptoms similar to malaria. This led him to theorize that if a substance given to a healthy person induced certain symptoms, it could be used to treat those same symptoms in an ill person. This idea is Dr. Hahnemann’s “law of similars.” He believed, however, that the concentrations that caused symptoms in a healthy person were too strong for treatment of an ill person. This consideration led to the minimum-dose principle, or “law of infinitesimals,” which states that the therapeutic potency of a substance increases with more dilutions. In homeopathy, the most important part of the dilution process is a vigorous shaking of the solution after each dilution, so as to imprint the substance’s nature on the water.The last principle Dr. Hahnemann proposed is that of holism, or the “single remedy,” which is the belief that one remedy should be used to address all of the symptoms that a patient experiences. In consultation with a patient, the homeopathic practitioner aims to capture all aspects of physical and mental state, in order to best tailor the treatment to the individual. The remedy is chosen to address the total set of symptoms, instead of just those directly related to a disease. While classical homeopathy upholds the holistic, single-ingredient approach, modern homeopathy has adopted a broader definition, and some treatments do include a mixture of ingredients. Modern Homeopathy Today, homeopathy is categorized as a type of complementary and alternative medicine. It’s often confused with the practice of herbalism, another form of CAM. It’s important to understand the difference between the two: Herbalism typically employs the use of mixtures of plants and herbs, while homeopathy usually uses ultra-high dilutions of a single natural substance in one of its remedies. The conditions that homeopathy claims to treat range from cataracts to allergic conjunctivitis and, while not clinically proven, the treatments remain largely free of potential harm to patients. Cineraria maritima, derived from the tincture of the dusty miller plant, is purported to prevent or retard the formation of cataracts. One brand of homeopathic drops for cataracts contains active ingredients cineraria maritima 6X (denoting that the solution was diluted in a 1:10 ratio six times),7 conium maculatum 6X (from the poison hemlock plant) and phosphorus 12X.Other ophthalmological remedies include pulsatilla (from the wind flower) for “conjunctivitis with thick yellow discharge,” and silica for blocked lacrimal ducts.2 One homeopathic dry-eye drop contains mercurius sublimatus 6X (mercuric chloride) indicated for dryness, belladonna 6X (from the deadly nightshade plant) for dryness and redness, and euphrasia 6X (from the eye-bright plant) for redness and inflammation. Proof of Efficacy Throughout history, homeopathic remedies have been confronted by much skepticism and opposition from the scientific community. In one of his medical essays, the 19th-century physician Oliver Wendell Holmes made the following comment on Dr. Hahnemann’s principles: “When one man claims to have established these three independent truths, which are about as remote from each other as the discovery of the law of gravitation, the invention of printing, and that of the mariner’s compass, unless the facts in their favour are overwhelming and unanimous, the question naturally arises, is not this man deceiving himself, or trying to deceive others?”Today, opponents of homeopathy argue that no matter how intensely the results of serial dilutions are agitated, there isn’t any physical presence of the active ingredients if they are diluted to below Avogadro’s number. Moreover, while there are published claims that the ultra-high dilutions of substances may involve phenomena at both the molecular level and in the structure of water, these results have not been consistently reproducible. Clinical trials to substantiate the efficacy of homeopathic remedies have been conducted, but the results are mixed.Some supporters of homeopathy insist that due to the nature of the remedies, efficacy should only be determined on the basis of patient satisfaction, rather than clinical trial results. A similar sentiment appears to be shared by the U.S. Food and Drug Administration, as efficacy trials aren’t required prior to the sale of the highly diluted homeopathic remedies. Labels for homeopathic remedies sold over-the-counter only need to include an ingredients list, instructions for safe use, an indication for at least one self-limiting condition and the dilution strength. Those claiming to treat serious, non-self-limiting diseases (e.g., cancer) must be sold by prescription only, and must include a cautionary statement of the prescription status of the drug, a statement including recommended dosage and a package insert bearing the labeling information for the homeopathic practitioner.In contrast, for most conventional medications, especially prescription, proof of efficacy through clinical trial results is pivotal to FDA approval. In fact, the FDA relies on an entirely separate entity, the Homeopathic Pharmacopoeia Convention of the United States (HPCUS), to define and catalog the current homeopathic ingredients. To be accepted by the HPCUS, a substance must have either “homeopathic provings” or be known to induce symptoms that mimic the condition it’s intended to treat. The substance must also be manufactured according to HPCUS criteria.Natural Fad or Telling Trend? Despite the lack of active ingredients and of controlled clinical proof of efficacy, homeopathy is thriving. The rising popularity of homeopathy and other natural therapies has been suggested to correspond to the beginnings of the holistic health movement in the 1970s and the New Age movement of the 1980s. In a 1999 survey, more than 6 million Americans reported having used homeopathy in the past year,and an estimate of homeopathic drug sales in the United States in 2003 exceeded $300 million dollars.Proposed reasons for this choice include the natural ingredients, the holistic approach of a practitioner, who usually takes around twice as long as a conventional clinician to carefully tailor the treatment to the individual; and the lack of side effects due to the high dilutions. Other factors may also influence patients’ choice of homeopathic treatments. An Italian survey of 30,000 families revealed that 8.2 percent of the population had used homeopathy in 1999 and 2000. Within this population, the reported reasons for using homeopathic remedies were lower toxicity (71 percent), they were the only therapy available (22.6 percent), greater efficacy (20.5 percent), better doctor-patient interaction (13.2 percent), cultural belief (10 percent) and unknown (8 percent). In some instances, culture and homeopathy may be a marriage of convenience. For instance, homeopathy is booming in India, where it represents a growing industry estimated to be worth $165 million. It also plays a large role in the country’s health-care system. Homeopathy’s emphasis on the importance of treating the whole body, rather than just the ailing part, jibes with ancient Indian medicine, including Ayurveda, Yoga, Unani and Siddha, and is theorized to be the reason for its prevalence throughout the country.A distrust of corporate “Big Pharma” likely influences Americans’ choices in health care today. The perception that pharmaceutical companies are primarily interested in profit, rather than consumer health, has only been fueled by recalls of products due to serious, yet unexpected, side effects. Perhaps the appeal of homeopathy’s harmless nature, with the chance of efficacy, is enough to entice patients who feel unsettled by the ingredients and side effects of modern therapeutics. Marketing Lingo Even though homeopathic remedies appear to be cut from a different cloth than the drugs of major pharmaceutical companies, they are still sold by a for-profit industry. Direct-to-consumer prescription advertising, while regulated by the FDA, is controversial for both pharmaceuticals and alternative therapies. Since patients seldom seek medical advice before buying over-the-counter products, they are especially prone to often-misleading marketing jargon. For example, some advertisements for homeopathic remedies indicate “clinically proven” results alongside “homeopathic” in order to enhance the perceived credibility. Advertisements for a currently marketed zinc nasal gel for the treatment of common cold symptoms display the tag, “clinically proven to get you over your cold three times faster when taken at the first sign of a cold.” It’s easy to imagine how this statement can give the impression that the homeopathic remedy is three times better than conventional cold medications, even though the advertisement does not mention what the product’s efficacy was actually compared to. The reference for this claim reveals that the study was actually performed versus placebo and is not, in fact, a measure of efficacy versus a conventional cold treatment. The same company claims, “No side effects. Just real relief,” for its homeopathic nasal gel for nasal and ocular allergies. True to homeopathic principles, the active ingredients of the nasal gel include histaminum hydrochloricum 12X—a fancy name for a solution of the very molecule that elicits itching. Natural Derivatives in Drugs Perhaps what’s often overlooked is the presence of natural ingredients in conventional therapies, although they’re not usually known to elicit symptoms of the condition. One of the artificial tears available for the treatment of dry eye contains a derivative of the guar shrub as its gelling agent, HP-Guar, to approximate the glycocalyx, adhering the tear film to the epithelial cells. Cyclosporine A is a cyclic polypeptide produced by the fungus Beuveria nivea, and is known for anti-inflammatory properties. Several natural products, or derivatives thereof, have endured time and regulatory evaluations to remain present in modern medicines and are estimated to represent one-third of the top-selling drugs. While perhaps not conspicuously displayed on packaging or in advertisements, natural derivatives still constitute a fair portion of modern-day ophthalmic agents. So, what is driving patients to homeopathic medicine? It seems that whatever the direct cause, our patients may not be so far off from what Dr. Hahnemann created at the core of homeopathy. Perhaps patients are uncomfortable with the potential side effects that are sometimes related to conventional medicine, and see a safer alternative in homeopathic remedies. When consulting with patients who use, or who are interested in using, homeopathic or alternative choices for their ophthalmic conditions, it’s important to emphasize the distinction between evidence-based therapeutics and homeopathic remedies. While conventional therapies may contain a higher toxicity, they are regulated by the FDA and are required to demonstrate proven safety and efficacy through controlled clinical trials. Furthermore, some even contain natural derivatives. Taking the time to actively listen to patients and then explain these facts could increase patient compliance and put patients at ease. When confronted with a patient who insists on taking homeopathic cataract eye drops, know that while they may not result in a miraculous recovery, they’re very unlikely to worsen the condition.
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Print kit has packs of appeal

Heidelberg Printing Machine While Drupa is mainly targeted at the commercial print sector, there is plenty to interest the packaging printer. Demonstrations of the latest kit in the three main print processes will be foregrounded, together with plenty of interesting developments in post-press and value-added finishing. At Drupa 2004, packaging experts predicted that at the next Drupa the flexographic process would match other packaging print processes for quality and cost-effectiveness. Four years later, it’s debatable whether that has actually happened, but Drupa will certainly be a showcase for several developments that promise to push flexo closer to pole position in the near future, taking market share from both offset and gravure. The Flexo4All strategic alliance – 19 of flexo’s most influential suppliers and manufacturers from around the world – will promote flexo for packaging at Drupa. Its members read like a ‘who’s who’ of the packaging industry: Bobst, DuPont, EskoArtwork, Fischer & Krecke, Gallus, Sun Chemical, Uteco and Windm?ller & H?lscher among others. The group, which is the latter-day incarnation of DuPont’s 20-year-old Flexo – The Alternative initiative, will seek to encourage networking within the flexo industry, connecting competence and promoting flexo as “the best technology to satisfy all printing needs”. DuPont’s EMEA marketing manager for packaging graphics, Pier Luigi Sassanelli, believes that flexo is “ideal for almost all substrates, all segments, all applications and all budgets, and more.” Versatile flexo There have been improvements in flexo technology over the past five years – a massive boost with the introduction of digitally imaged plates, together with parallel improvements in inks and anilox systems. It is certainly a versatile process, with the ability to print onto absorbent and non-absorbent, flexible and rigid substrates. It is also fast, with speeds of 500 metres per minute common. Its claim to cost-effectiveness rests partly on the relatively inexpensive levels of investment compared with offset and gravure, and partly on the fact that some finishing processes can be added inline, eliminating inter-process handling costs and time. There is even the claim that flexo presses are more environmentally friendly, although this assertion is not about energy use so much as the fact the process can use water-based and solvent-free inks. But even with all these manifest advantages, Flexo4All’s claims to supremacy may remain optimistic, given that the quality of flexo printing has traditionally come a poor second, or even third, to offset litho and gravure. Flexo print is known to suffer from fluting and ghosting due to poorly formed dots on the printing plate. The problem is that an ordinary flexo platemaking process produces dots that look like a range of mountain peaks, due to oxygen that is hard to eliminate from the polymerisation stage of the process. A peak-shaped dot does not transfer ink precisely from its top face because the peak compresses during contact with the substrate and transfers ink from the sides as well as the pointed tip – hence the ‘fluted’ effect. To combat this, most studios apply a tonal curve that effectively makes the smaller dots bigger and the bigger dots smaller. But the effect of that is to allow only a limited tonal range to be printed. However, several initiatives are underway to combat the limitations of the flexo platemaking process. The aim is to eliminate oxygen, thereby creating a plate with a flat-topped dot that can reproduce a full range of grey levels. The three companies working on this process have taken different approaches. US trade platemaking house PRP Flexo has a proprietary process for supplying flat-top-dot plates to other flexo printers. Kodak offers a complete system encompassing Flexcel digital plate, thermal top layer, platesetter, laminator and even a workflow. UK flexible packaging film printer TCL Packaging’s proprietary Fotoflex process has focused on the screening process with additional adjustments on the press for optimum results. UV flexo is also an established technology, particularly in the labelling sector. The process uses minimal Volatile Organic Compounds (VOCs) and gives faster makereadies, besides doing away with the need for pressroom climate control, thereby cutting energy costs. And because of brighter colours and superior scuff, fade and chemical resistance, UV flexo has also gained wide acceptance by packaging buyers. Gidue will be at Drupa to show off its UV flexo mid-width webs; likewise Carint, Edelmann, Focus Label Machinery, KPG Europe and Muller Martini all have offerings in the UV flexo area. Windm?ller & H?lscher is staying on after its appearance at Interpack to show the Miraflex C press, a common-impression flexo machine with eight to 10 colour decks and printing widths from 1-1.45m. Developments in ink (see box on page 51) are also pushing up flexo’s quality, cost-effectiveness and green credentials. Fischer & Krecke’s WetFlex will be shown: entirely without inter-deck drying, the WetFlex uses inks developed by Sun Chemical that allow wet-on-wet printing with only a single drying shot delivered last in the line by an electron beam (EB) curing unit. Digital delights Digital technology made its first forays into the packaging sector more than a decade ago, with the launch of HP Indigo’s first web-fed label press. The uptake of digital has since accelerated to make it the sector’s biggest growth area. Digital’s impact on the packaging sector has been partly due to its substrate flexibility – everything from light-gauge board to flexible films can be printed digitally – and for its variable data capacity, which no other print process can replicate. In the short-run arena, digital continues to take work from offset and gravure. The technology also continues, through its innovatory attributes, to create entirely new markets that simply did not exist before – such as metal can decorating in runs as short as one, exemplified by Impress’s dPrint digital system. Digital’s original capability for only a limited-gamut colour reproduction from four-colour toners or inks initially held it back in packaging, with the sector’s demand for vivid and precisely-matched colours. But this year’s Drupa will demonstrate that this gap has been closed: HP Indigo, Xeikon, Océ and Canon now all number four-colour-plus printing among their machines’ capabilities. Many are hailing this year’s exhibition as ‘the inkjet Drupa’, and while most of these developments will concern commercial printers, packaging printers will be particularly interested that several wide-format digital inkjet manufacturers have turned their attention to the packaging market, offering a press for the purpose. Raster Printers, of Bicester, has targeted carton printers with its new Daytona H7000UV wide-format flatbed that can print onto any rigid or flexible material at speeds up to 29m2 per hour. If packaging printers can find a use for this type of technology, other wide-format printer manufacturers may follow: there are applications in short-run carton work, model-making and variable-data packaging. Cambridge-based Tonejet also has designs on the digital packaging sector with its new wide inkjet head, which it intends for food and drink carton print. Meanwhile, there are fringe developments of inkjet technology that are directly aimed at the packaging sector. At Drupa, Nilpeter will demonstrate Caslon, a modular digital print solution for labels and narrow web packaging using four-colour process UV inkjet technology. Caslon can be integrated into Nilpeter’s conventional flexo press lines, or can function as a stand alone roll-to-roll system. Developed jointly by Nilpeter and FFEI, Caslon uses the latest Xaar 1001 printheads. This variable drop (greyscale) printhead features Xaar’s patented Hybrid Side-Shooter platform with TF Technology designed to produce dynamically variable drop sizes needed for fine detail and readable small text and smooth tones reliably and consistently in single-pass applications. Inks manufacturer Sun Chemical is also getting involved in hardware, with its new SolarJet UV flexo label press for short runs: the press is intended for runs of up to 10,000 labels for the pharmaceutical and health and beauty sectors, and uses Xaar 760 inkjet printheads. On the non-inkjet digital score, there are plenty of new packaging-led developments at Drupa. HP will show a new web-fed Indigo for label and packaging work, the ws6000. This big brother to the well-known ws4500 is designed mainly for high-volume customers, printing at up to 30 metres per minute. Like other HP Indigos, the ws6000 can print up to seven colours, together with a new improved white, which label and flexible packaging printers will find useful. Xeikon will also launch a new web-fed press, the 8000, capable of printing onto a wide range of substrates including flexible films and self-adhesive label stocks – this builds on the corporation’s initial foothold in the digital packaging market through the original 6000 press. The slow but ineluctable decline in CD and DVD sales in favour of downloadable digital content is responsible for a corresponding decline in machines for printing CD/DVD packaging. Here, however, digital press manufacturers are experiencing growth in sales as runs become shorter and have less lead time: printers specialising in this area are turning their attention to digital as a cost-effective answer to a changing market demand. An interesting fusion between workflow and digital print will be in evidence at this year’s Drupa, with front-end controllers for digital presses being shown by workflow developers: EskoArtwork’s Labels and Packaging SmartStream PrintServer has been developed especially for HP Indigo’s digital presses, and there is evidence that the web-to-print boom, riding high in commercial print, may also find some limited, customer-specific footholds in the labels and packaging sector in the next two years. Finishing school The post-press sector looks a little different at Drupa this year, due to the continued drive among manufacturers to keep as much finishing as possible inline to the press, thereby eliminating handling time and costs, together with floorspace and the extra capital investment in separate post-press machines. This trend has always been marked among narrow web and flexo press manufacturers, and this year’s Drupa backs up the point with new launches from Gallus among others, which link die-cutting units inline for integrated production. Sheetfed litho press manufacturers could be said to have taken a leaf out of the flexo press manufacturers’ book: Komori is one of several press manufacturers to be launching a new sheetfed press with inline cold foiling, UV coating and embossing at Drupa. Like all inline processes, the added-value units on the Komori machine slow it down by about 15-20%, but that still makes the processes much cheaper than offline equivalents. Other sheetfed packaging presses that aim to incorporate processes inline include Heidelberg’s new super-size 145 and 162cm presses, MAN Roland’s new size 7, 7b and 8 presses, and KBA. The theme of automated, integrated production is continued into standalone post-press machinery. Heidelberg will launch a new folder-gluer, the Diana X 115: not only is the line capable of processing 200,000 cartons per hour, it also boasts a new auto-feed and a delivery packer. Die-cutting is also moving towards integrated production, with a raft of machines newly extended to incorporate functions such as embossing and foil-blocking in a single pass – these include Heidelberg’s Varimatrix 105CSF die-cutter with foiling and embossing and Blumer’s Atlas label cutters, which will be hitched inline to a label press. Chinese manufacturer Masterwork will launch a new ‘hybrid finishing line’ – effectively a die-cut, foil and stripping line – while Saroglia will show an integrated die-cutter, foiler and embosser. Ehret Control will show a label finishing line for die-cutting or strip cutting. There also appears to be a continued trend towards short- and ultra-short-run cutting at Drupa. EskoArtwork will show Kongsberg XP digital cutters, while Saroglia will also show a new laser cutter for packaging applications. Elsewhere in post-press, technology developments focus on minimising makereadies and the reduction of waste. Bobst, famously taciturn about its exhibition launches before any show opens its doors, has said that it will launch a new generation of its Power Register technology – a dynamic registration control software that uses photocell technology to reduce unplanned stops due to misregistration of the die to the sheet. Also of interest is Japanese sheetfed press manufacturer Shinohara’s Casting Curing Unit (also known as C2): this offline UV coater flash-cures a varnish by projecting UV light through a patterned film to achieve a subtly imaged effect on the varnish, for decorative or security applications.
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RKC Instrument announces new digital indicator

RKC Instrument announces the new AG500 microprocessor-based digital indicator in a panel saving 60mm depth 1/8 DIN case. The 21mm high LED readout has a luminance double that of conventional indicators and the easy-to-read five digit display. The options available for the AG500 include universal input types, up to six programmable alarms, analog retransmission, digital input, 12 or 24 V DC sensor power supply and RS-485 or MODBUS-RTU communications. With digital communications, the indicator can be used in conjunction with a PC or PLC; with the analog retransmission output, it can be used with a chart recorder or data acquisition system. In addition to the process high and low alarms, alarming standards of the AG500 include a latch function, an alarm timer delay, and hold action. The alarm status can be checked easily with alternate displays of process value (PV) and alarm number. The AG500 memorizes the maximum and minimum measured values. An optional contact input enables you to remotely reset the value. Each unit carries a full three-year warranty. Suitable applications include plastics and packaging machines, ovens, furnaces, kilns, textile dyeing, food baking, petro chemical, semiconductor, test stands, environmental chambers and other heater processes.
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Versatility the key to valve usage

Manufacturers suggest you consider four main criteria in selecting a pneumatic directional control valve: valve function, type of valve actuation, installation arrangement, and the flow capacity (or valve size) needed for the actuator. The first three are pretty well defined by the application. The fourth — valve size — also is defined by the application, but it takes some work to dig out an accurate figure. Most pneumatic system designers know that the main configurations (how the valve’s internal pathways are connected) for directional control valves are 2/2-, 3/2-, 5/2-, and 5/3- way. The first number represents the number of ports, and the second number deontes the number of discrete positions. Likewise, designers can easily determine whether actuation will be manual or mechanical, by solenoid, by pilot pressure, or by a combination of solenoid and pilot pressure. Installation options cover a little more ground, but most encompass stand alone (in-line or sub-base) or manifold mounting. Wiring can be plug-in or hardwired, and serial communication makes wiring simpler, faster, and much less expensive. Avoid pressure drop In conjunction with the first three main criteria, the most important decision — from the viewpoint of economical operation — is matching the valve’s flow capacity to the application requirements. Air flow usually is measured in cubic feet or liters per minute. A component’s flow coefficient (a unit-less number designated as CV) is an indication of the amount of resistance to flow that the component presents. Flow coefficients for air valves are available from their manufacturers. All devices that conduct air resist flow to some degree. As a result, Air valves abound in versatility as air flows through a restriction, its pressure drops. The less resistance, the lower the pressure drop, also called ΔP. The amount of pressure drop across the restriction increases exponentially as flow increases. Any pneumatic device — even a fitting or run of tubing — will affect the flow rate in a system. In rapidly cycling applications, a few extra inches of tubing or the wrong fitting can mean the difference between a circuit that works as designed and one that misses the mark. For this reason, valve flow ratings alone cannot predict the flow rate through a system or branch. All components must be considered. Size doesn’t matter In the past, sizing a valve simply involved matching the port size of an actuator to the valve. Today, however, it no longer is even suggested as the way to size an air valve. Technological advancements now allow physically smaller valves to pass much greater flows, so port size has become even less significant. Smaller valves tend to have several advantages over larger valves. In general, these include: faster shifting, less leakage, lower power consumption because smaller solenoids can move lighter internal parts, greater mounting flexibility because valve footprints are smaller, and lower cost. But small size isn’t the only advancement of today’s air valves. Serial communication, innovative designs, and proprietary configurations give designers a much wider variety of products to choose from . We present a small sampling of this variety on gthis and following pages.
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