Division of Agricu a I Sciences r TRAMP CONTROL AND REMOVAL JOHN B. DOBIE JOHN P. HUGHES FREDERIC C. JACOB A* METAL PUT INTO CONTAINERS >VIDED FOR SUCH PURPOSES WON'T DAIRY OR BIEF CA 1^1 III S J III % % y ^ CALIFORNIA AGRICULTURAL t Station CIRCULAR 489 TRAMP IRON Causes losses to cattlemen of from $4 to $6 million \ annually. Hardware disease is the popular name for the con- dition caused by ingestion of sharp foreign articles that puncture the reticulum (second stomach compart- i ment) of ruminants. Presence of dangerous metal pieces in cattle is sur- prisingly high. Slaughterhouses have reported inci- dence in as much as 90 per cent of all cattle killed. « Cattle checked with a metal detector have varied from t 50 per cent incidence in well-managed herds, to as high as 90 per cent. The greatest loss is from dairy animals killed or - temporarily out of production due to hardware dis- ease. Veterinary clinic reports for 1951-53 showed 87 per cent of the victims to be dairy-type cattle; in range areas, beef animals account for a higher proportion of the cases. This circular tells how to . . . AVOID the problem by cleanliness around the farm. REMOVE METAL from feed in the field or in feed-handling equipment. RECOGNIZE ANIMALS that are suffering from hardware disease. This publication will not, however, substitute for a veterinarian. Stricken animals should be under the care of competent medical advisors. THE AUTHORS: John B. Dobie is Associate Research Engineer in Agricultural Engineering, Davis; John P. Hughes is Assistant Professor of Veterinary Science and Assistant Veterinarian in the Experiment Station, Davis; F. C. Jacob is Lecturer in Agricultural Engineering and Associate Agricultural Engineer in the Experiment Station, Davis. AUGUST, 1960 IT'S AN EVER-PRESENT HAZARD Study of veterinarians' reports indi- cates that there has been a shift from nails to wire of the offending metal par- ticles over the last 25 years. Wire now accounts for about 75 per cent of the cases; nails 20 per cent; and miscellane- ous objects 5 per cent. Nearly all tramp metal has been ferromagnetic. Pieces 2 to 4 inches long are most troublesome. In the majority of cattle, metal is found only in the reticulum, although a few, particularly bulls, may also have it in the rumen. Clinical reports indicate that the problem is increasing due to the use of more chopped feeds, more feed contami- nation, improved diagnostic facilities, or combinations of all three. Tramp iron exacts a costly toll in farm machinery repairs. Stray metal can dam- age chopper knives, feed rollers, feed grinders, pellet mills, and other process- ing equipment. Commercial feed plants find that it pays to guard against stray iron getting into their machines, but low use factor for farm machines and unavail- ability and cost of suitable preventive equipment have limited similar safe- guards in farm operations. Tramp iron has caused numerous fires in grinding equipment. Sparks or p : eces of red hot metal in ground-feed storage may cause a fire — or if the conditions are right, an explosion. Insurance firms often uprate coverage where hay is ground in the mill because of the diffi- culty of removing tramp iron from hay before grinding. Sources ... in feeds Although there have been occasional reports of cattle deliberately eating wire, nails, or similar objects, it is felt that most tramp iron is consumed with some form of feed. Hardware disease is a par- ticular problem in cattle because of their undiscriminate eating habits, the ana- tomical arrangement of their stomachs, and the large amount of tramp iron avail- able. In an experiment performed at Davis, six 3-inch pieces of baling wire were mixed into grain fed to each of two cows. The cows cleaned up the grain, and in the process swallowed all of the pieces of wire. Forage makes up a large part of the ruminant's diet, and because of its coarse, stemmy form provides a good hiding place for foreign material. Hence, forage is probably the source of much of the tramp iron found in cattle. Some sources of contamination are listed below. In the field Baling wire from faulty balers or broken bales. Carelessness in operating balers. Broken or hay-wired machinery parts falling in the field. Fence wire, either from building or re- pairing stationary fences, or from mov- ing portable fences. Nails and staples, pulled out of equip- ment or fences, or accidentally dropped in the field. Trash piles for burning. Wire remains in the ashes after burning and may end up back in the field. Manure hauled to the field. (Manure piles seem to be natural collectors of all types of refuse.) Field chopping or pelleting of hay may transform long pieces of wire into short, [3] dangerous lengths. Alternate baling and chopping in a given field can be particu- larly dangerous. Roadside fields are recipients of trash such as cans and bottles. Cans that have gone through a chopper or grinder are particularly dangerous. In storage Trash in the form of cast-off wire, cans, nails, etc. Nails dropped from roof of structure. Tools or machine parts dropped in moving feed in and out of storage. In processing Machine parts, particularly bolts and pieces of grinder knives and screens. Pieces of hand tools, particularly fork tines. In feeding Machine parts, such as conveyor or feed wagon parts; hay wired machines. Broken pitchfork tines or other hand tools. What can be done? The tramp iron problem can be at- tacked in several ways, depending upon the point to which it has progressed. Prevent the source of contamination by good management. Use equipment to remove tramp iron from feed. Obtain preventive and medical treat- ment of animals by the veterinarian. YOU CAN PREVENT TROUBLE . . . Carelessness or poor management can be blamed for the high incidence of tramp iron on many farms. Some farms have placed a premium on "good house- keeping." Here are some of the ways it can be done. Have plenty of trash barrels handy for refuse. See that trash is disposed of safely and regularly. Make it a No. 1 rule for every em- ployee to go out of his way to pick up tramp iron and dispose of it properly. Once the property has been thoroughly policed, this will require very little time. Use manure piles for manure only. No refuse! Bunch wire bale ties immediately upon removal from the bale. Collect in trash barrel. Dispose of them regularly. Place broken or discarded tools in the trash barrel. They are a hazard to people as well as being a source of tramp iron. Eliminate the dangerous practice of haywiring broken machine parts. If you don't fix it correctly at once, you prob- ably never will and the broken parts — plus the haywire — will end up in the field. Operate hay balers properly. Don't leave wire in the field to be picked up in future cuttings. Twine-tie balers will help. Be careful with tools when working on machines. Check carefully to see that you have picked them all up before starting the machine. Do not buy hay from a field known to be wire-infested. Avoid dropping nails, staples, or pieces of wire when repairing fences, feed-stor- age buildings, or feed mangers. Bolts are much better than nails or screws in field equipment made of wood. Educate new workers immediately and place a premium on their cooperation. Sweep magnets can be purchased or rented for an initial cleanup over large, level areas. Cleanliness is habit-forming. Incidence of tramp iron can be reduced materially by an initial policing but continuous ef- fort will be required to keep it clean. [4] REMOVE IT BY MACHINERY There will always be conditions that result in some feed contamination, but various types of equipment have been devised to remove tramp iron from feeds. Ground or granular feeds can be cleaned of tramp iron rather easily with simple, inexpensive equipment. Fibrous, stemmy material such as hay presents a more difficult problem. Plate magnets The simplest and least expensive de- vice for removing tramp iron is the plate magnet. It can be obtained in various sizes to fit most any flow of feed and is used in various ways, as shown in the drawings. It is particularly effective with granular or ground feeds. It can be used with forages, but with less success unless given special and continuous attention. Plate magnets are most successful where granular material is spilled onto or over the sloping face of the magnet. Under the same conditions, chopped for- age will be held on the magnet by the iron collected and will require frequent cleaning. Plate magnets are not self-cleaning, hence need occasional attention in any installation. An alarm device is available to indicate when the build-up of tramp iron reaches a predetermined amount. ^> Plate magnets may also be mounted above a belt conveyor . . . in a cup elevator . . . Simple adaptation of a plate magnet mounted in a chute. . . . on a feed grinder. [5] The duct or hump magnet This is an adaptation of the plate mag- net in which two such magnets are usu- ally installed in a pneumatic system as shown. Duct magnets work quite well with chopped forage; their effectiveness is dependent upon magnet strength and the velocity of the material. Minimum velocity to reduce plugging is about 5,000 feet per minute. At this velocity a duct magnet at full strength should re- move all the tramp iron, provided it is not allowed to collect until overloaded. Velocities in farm forage blower systems normally range upwards from 5,000 fpm with some measured over 10,000 fpm. Up to 8,000 fpm, experiments have shown that nearly all the tramp iron will be collected by a duct magnet in good condition. Over 8,000 fpm, efficiency falls off rapidly. These figures can be grouped fairly well according to the type of mill or blower handling the forage. . ESTIMATED EFFICIENCY TYPE OF MILL OF DUCT MAGNET Center throw (Miller) 75-95% External blower (Bearcat, W.W.) 70-85% Tangential throw (Papec, Fox) 20-50% Some manufacturers do not recommend their duct magnets for use on tangential throw forage blowers. Where possible, a unit of the type shown below may be used for gravity or low-velocity flow. Another reason for poor efficiency may be a gradual reduction of magnetic strength due to disassembly or repairs. Duct or hump magnets showing method of mounting in (left) a pneumatic installation, and (right) in a gravity installation. [6] Magnetic grate A rotating grate of rod magnets may be used to remove tramp iron from most feed materials. These grates are avail- able in a range of sizes to fit most instal- lations. Maximum rotating speed should be 30 rpm with 15 to 20 rpm a good average speed. Slower speeds may be necessary under excessive choke condi- tions. Tramp iron must be removed from the grate manually. Magnetic drum The magnetic drum is similar to a magnetic grate, except that the material to be sorted is spilled by gravity onto the surface of a drum that rotates around a 180° arc of permanent magnet. This system is best adapted to free flowing material, such as ground or granular feed that can be dropped onto the drum by gravity feed. The clean feed drops off the side of the drum. The tramp iron is carried past the magnet, then dropped, hence a magnetic drum is self-cleaning. A rotating grate magnetic separator. The magnetic drum arrangement is self- cleaning. [7] Magnetic pulley Magnetic pulleys are widely used as head pulleys in industry for the removal of tramp iron from material conveyed on belts. They may be either permanent or electric magnets, but permanent mag- nets seem most practical for farm use. Efficiency is dependent upon belt or pul- ley speed and the thickness and nature of the material conveyed. The iron is attracted through the material as it leaves the belt and is carried to the underside of the pulley where the belt pulls it out of the magnetic field, dropping it into a catchbox. The magnetic pulley is most adaptable to grains or ground feed. Test data indicate that all the tramp iron can be removed from wheat, barley, and oats about as shown in the table below. Removal of Tramp Iron from Wheat, Oats, or Barley by Magnetic Pulley DEPTH BELT OF LAYER SPEED CAPACITY INCHES FPM cu. ft./min Whole grain 1 430 42 2 385 75 3 240 70 Ground grain 1 410 40 2 240-320 45-60 3 150 44 Source: University of Idaho Leaflet No. 28, December, 1954. From the table, it is apparent that a depth of approximately two inches pro- vides optimum capacity. Fibrous mate- A magnetic pulley application is also self- cleaning. rials such as chopped hay can be handled with a magnetic pulley provided the layer of hay is thin. Some hay may be pinned to the pulley and carried into the scrap bin, however. Suspended magnets Magnets may be suspended over mov- ing belts to lift tramp iron out of a thin layer of material. An electromagnet may be used, permitting easy cleaning by turning off the electricity, or a self-clean- ing unit, as shown below, may be used. In the latter, the magnet and belt operate crossways of the conveyor so the tramp iron is carred over the side of the con- veyor belt. Suggested mounting for a plate magnet over a belt conveyor. This arrangement is self-cleaning. [8] Here are two signs that may be used in or around your barn or shop. These signs may be removed by tearing along the perforations. Put them in conspicuous places; provide trash bar- rels for tramp iron and other metal scraps; help keep your farm clean and your cattle healthy. ^ tf S ^ E © (A •*■ *- *- o o E » f ! E o> wi c o o £ "5 if s .2 u a. K ■ «*. o •£ JS © 1 is 1*3 I. 2 S M « = "P 2 5 i g o O) 8s § GL u) — «/* i/1 PS g"8 £ o «« **■ o o © 3 E °> 5 i T | i s £ o> «A C >* .2 > "5 o $ c £ .2 s ° -s U) © o H- O •£ «» *■ .t © Si lis o V CO 0) -5" CL = 23 v> .5 -r — in * u O 0. (A — w» «/» VI 8 %jy Combination gravity and magnetic systems Where the arrangement of the feed- handling plant permits, a combination gravity-magnet system can be used to advantage. An example of such an ar- rangement is shown. Feed falls by gravity through a vertical pipe onto a plate magnet, located just below the pipe. A suction pipe is located below the mag- net to pick up the light weight feed, at the same time changing its direction of flow. The iron is caught by the magnet or thrown out of the system by gravity. Principal advantages of such a system are that an inexpensive plate magnet can be used; collection of iron on the magnet does not cause plugging of the system; and inspection of the magnet is simpli- fied. Opening for gravity- throw-out of the heavy pieces Combination gravity-magnetic system. Electronic metal detectors In recent years, several metal detector- rejector units have been placed on the market. Most of them are limited as to Typical electronic metal detector installation with reject system at lower right corner. [9 the rate at which material can be passed through the inspection coil to 600 fpm because of the use of alternating current to energize the detector coil. While this is satisfactory for use in commercial plants where many products are con- veyed on belts below this maximum speed, there are very few opportunities for use on farms. A further limiting fac- tor has been the cost of these a.c. metal detectors. A metal detector has been developed at the University of California designed for use with the most common hay and feed conveyor for farm use — the pneu- matic conveyor. The pneumatic conveyor moves material at high speed, usually between 5,000 and 10,000 fpm. To op- erate satisfactorily at these high speeds, the detector coil is operated on direct current or is mounted on a permanent magnet. At right is a schematic layout of the system, showing the relative posi- tions of the detector coil, the control system, and the reject unit. Clean hay or feed, regardless of moisture content, has Return spring Rejected hay tf- iron fed into blowter Schematic layout of U.C. electronic tramp iron Typical method of mounting a tramp iron remover on a field harvester. A — detector; B — amplifier-controller; C — reject unit; D — generator. 1 10] no effect on the detector. A piece of iron passing the detector coil causes a change in the magnetic field, creating a signal which is transmitted by cable to the con- trol unit. The controller amplifies the signal so that it can operate a high-speed relay, which in turn controls the reject gate. The gate, operated by a solenoid, is deflected into the reject position, mo- mentarily diverting the entire stream of air and hay. High speed operation is im- portant because of the velocity of the tramp iron passing through the pipe. Sensitivity of the system is such that it will detect %-inch pieces of baling wire or equivalent, and is sure to remove all pieces dangerous to animals. The re- jected hay and tramp iron must be col- lected for disposal. Stationary vs. field machines In order to handle all conditions under which hay is conveyed pneumatically on the farm, metal detectors for both sta- tionary forage blowers and field har- vesters are required. The system of tramp iron removal for pneumatic conveyors has been developed for both types of in- stallations and has been demonstrated to be highly effective for either opera- tion. The sketch on page 10 shows a typi- cal method of mounting the various components on a field forage harvester using a generator for power. The sta- tionary installation would normally uti- lize 115 volts a.c. Since the rejected hay and iron must not be returned to the hay field, easy-emptying or disposable collectors are provided on the field unit. TREAT STRICKEN ANIMALS Hardware disease is more often called traumatic reticulitis or traumatic gas- tritis by the veterinarian. These latter names indicate the area involved and suggest a pathological process. The wire may penetrate the reticulum and become walled off by body defenses resulting in a chronic local peritonitis, or it may penetrate deeper, follow various routes and involve such organs as the spleen, liver, lungs, and heart. Signs. Hardware disease may resem- ble simple indigestion, ketosis, displace- ment of various parts of the bovine gut, peritonitis from different causes, pneu- monia, and other diseases of cattle. This makes traumatic reticulitis a disease un- der almost constant consideration in dairy cattle practice. A number of procedures may be em- ployed to aid in the diagnosis, such as the characteristic signs of the disease, shifts in the blood picture as seen under the microscope, x-rays of the thorax to show the offending object, percussion over the area of penetration for signs of pain, and the use of detectors to prove that a metallic object is present. Some of the more reliable signs of penetration of the reticulum by a foreign object are as follows: Sudden drop in milk production. This may vary from a drop of a few pounds of milk a day to almost no production. Disturbed appetite. Some cows refuse feed altogether; others may eat hay but not grain. Attitude of pain. This may be shown by the characteristic arching of the back, by the head being held low, or by the reluctance of the animal to move and its slow, stiff gait. Atony of the rumen. This sign may vary from no rumen movement or "cud chewing" to merely a decreased rate of rumen activity. [in Constipation. The feces are often firm and passed infrequently. Pain on percussion. This is shown by increased sensitivity over the area ol penetration by the wire. These signs vary from case to case and may subside in 48 to 72 hours. To en- sure maximum benefit from diagnosis and treatment with early return of milk- ing cow to production, the veterinarian should be called when signs first appear. Methods of Prevention Bar magnets In the last few years increasing em- phasis has been put on preventive meas- ures in the control of hardware disease in the cow. Cooper in 1954, proposed the use of a bar magnet for controlling trau- matic gastritis. Carrol in 1955 and again in 1956, reported on the successful use of bar magnets in the control of trau- matic gastritis. The common bar mag- nets used are Alnico V., permanent magnets, cylindrical in shape and V2" to %" in diameter by 2%" in length. The reticulum with its constant temperature and freedom from shock is ideally suited to maintain a magnet's permanent quali- ties. These magnets are most effective in preventing hardware disease when they are given to heifers or animals not previously exposed to metallic objects. These magnets are left in the animal and retrieved only after slaughter. Foreign bodies which have already passed com- pletely through the reticulum will not be brought back. Occasionally wires will penetrate the reticulum above its floor, and these will also escape a magnet put in after penetration has occurred. It has been stated previously that al- most all troublesome metal is found in the reticulum. Our work and the work of others tends to show that it is best to take the cattle off feed for 24 hours before introducing the magnet with a balling gun, as this assures the maximum percentage of magnets reaching the reti- culum. Magnetic metal retrievers The Muffly magnetic retriever consists of a permanent magnet attached through plastic tubing by a cable. This instru- ment is passed through a mouth specu- lum, down the esophagus, and manipu- lated into the reticulum where the magnet picks up any free metal. After each pas- sage of the instrument and the removal of metal, the animal is tested with a de- tector to determine if metal is still present. A bar magnet (slightly enlarged) removed from the reticulum of a cow, after slaughter. Note the collection of iron pieces. A schematic diagram showing use of the Muffly magnetic retriever. A second type of magnetic metal re- triever is made of an aluminum alloy tube in which is housed a jointed alumi- num alloy tube with attached magnet. This instrument is passed through a tube in the left flank of the cow and directed into the reticulum. Metallic objects are picked up and brought to the outside. The animals are tested each time with a detector to make sure all tramp iron has been picked up. These two examples are representa- tive of the magnetic metal retrievers in use by veterinarians. They show particu- lar promise as a means of removing lethal metallic objects from the reticulum of cows. These are best used as a pre- ventive measure in cows with metallic This diagram shows the use of a metal retriever inserted through the cow's flank. Note that retriever is inside of a metal tube so sharp material will not scratch when being withdrawn. [13] objects in the reticulum, before penetra- tion has occurred. After penetration, the magnetic metal retriever may fail to re- move the wire. Medical treatment Conservative medical treatment may be used by veterinarians on cases in which, in their considered judgment, it is desirable. Confinement of the animal in a stall or stanchion, with elevation of the foreparts may be advised. This re- duces pain and aids in walling off of the penetrating object. Used with medi- cation to control the infection, this pro- cedure may bring about prompt re- covery. Surgical treatment Rumenotomy is the surgical procedure used as a method of choice by many in the treatment of traumatic reticulitis. The operation is done with the animal in a standing position and under local anesthesia. The veterinarian makes an incision in the left flank, opens the rumen and reaches down into the cow's reti- culum to find the foreign body. If called early, the veterinarian is able to remove the offending object and thus return the animal to normal. Cows recover from this procedure very rapidly and the oper- ation has a high percentage of success. Slaughter Depending on the value of the cow as a breeding and production unit and also upon the seriousness of condition, as de- termined by an examination of the cow, slaughter may be advised. Some animals having an extensive peritonitis or in- volvement of the heart, lungs, liver, and other organs may be condemned and sent to the rendering plant. LITERATURE CITED Knight, W. H. and E. G. Craig, Tramp Iron in Livestock Feeds. Leaflet No. 28, University of Idaho, Dec. 1954. Carlson, Vance A. Removal of Magnetic Foreign Bodies by Paracentesis. J.A.V.M.A., 133 (1958): 261-263. Carrol, R. E. Magnets in the Control of Traumatic Gastritis. J.A.V.M.A., 127 (1955): 311-312. Carrol, R. E. The Use of Magnets in the Control of Traumatic Gastritis of Cattle. J.A.- V.M.A., 129 (1956): 376-378. Cooper, H. K. A Proposed Procedure for Controlling Traumatic Gastritis. J.A.V.M.A., 125 (1954): 301-302. Muffly, J. A. Nonsurgical Removal of Foreign Bodies with a Magnet. Proc. A.V.M.A. (1955): 48. Nelson, F. S., Jr. Magnets: A Therapeutic Agent in the Treatment of Traumatic Gastritis. [14] This publication was made possible through the cooperation of the California Agricultural Ex- periment Station and the California Committee on the Relation of Electricity to Agriculture. Acknowledgment is made to J. V. Galindo and R. George, Assistant Architectural Draftsman and Senior Draftsman, respectively, who made the drawings used in this publication. In order that the information in our publications may be more intelligible, it is sometimes neces- sary to use trade names of products and equipment rather than complicated descriptive or chemical identifications. In so doing, it is unavoidable in some cases that similar products which are on the market under other trade names may not be cited. No endorsement of named products is intended nor is criticism implied of similar products which are not mentioned. Co-operative Extension work in Agriculture and Home Economics, College of Agriculture, University of California, and United States Department of Agriculture co-operating. Distributed in furtherance of the Acts of Congress of May 8, and June 30, 1914. George B. Alcorn, Director, California Agricultural Extension Service. 20m-8,'60(B865)WP **2 l^#fi^.duviEBJ "stunt". . . This is probably the world's largest plow— it was built about 1910. It plowed an acre in four and one-quarter minutes. A swath 60 feet wide was turned under by 55 bottoms, pulled by three oil-burning tractors. The monster plow was built in sections and assembled for several test runs in the midwest. Impractical? . . . no! This "stunt" yielded new knowledge about hitches . . . knowledge that agri- cultural engineers have used in designing many of today's farm implements. For more than 40 years agricultural engineering has offered opportunity to young men of mechanical bent with an interest in agriculture. And as mechanization increases on farms, opportunities in agricultural engineering expand . . . with the GOOD JOBS going to those who are WELL TRAINED. Many leaders in the field were trained at the University of California at Davis. The staff at Davis is recognized nationally and internationally for its accomplishments in teaching and in research. The Department of Agri- cultural Engineering is accredited ... a graduate is eligible for examina- tion for a Professional Engineer's license, or he may continue study toward a master's or doctor's degree. The growing College of Letters and Science on the same campus broadens the student's educational and social back- grounds. For further information . . . about courses and careers in agricultural engineering, write Mr. Roy Bainer, Chairman, Department of Agricultural Engineering, University of California, Davis. Or . . . See the College Entrance Advisor in the office of your local Farm Advisor.