Bermuda King L.L.C. Senior Design Project

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1 Bermuda King L.L.C. Senior Design Project Fall Report Submitted by Cash Maitlen Darren George Mickey Friedrich Matthew Steinert 11 December 2002 BAE 4012 Dr. Paul Weckler

2 Introduction... 2 Prototype Machine... 3 Statement of Work... 4 Design Criteria... 5 Testing... 6 Initial Testing... 6 Floor Chain Measurement and Planting Rate Capabilities... 8 Developing a Baseline... 8 Definition of Problems Solutions Approach Proposal # Proposal # Proposal #

3 Introduction Bermuda King L.L.C.; of Kingfisher, Oklahoma, is an industry leader in the development of Bermuda grass harvesting and planting equipment. The company s chief products include various configurations of grass sprig planters and harvesters. Started in the late 1950 s by Willard Duffy, Bermuda King is currently owned by Brent and Brian Henderson. The company has recently expressed a desire to improve their current planter designs in order to stay competitive in the market place. The need to improve and update these products has led to an association with the department of Biosystems and Agricultural Engineering (BAE) at Oklahoma State University (OSU). In particular, students in the BAE senior design class have worked directly with Bermuda King and Clay Buford P.E., an application engineer employed by the OSU extension service. This partnership has yielded positive results in the past and is expected to continue into the future. Within the senior design class, a group of four BAE students have created a team named Creative Solutions Incorporated (CSI). Bermuda King has sought the inspiration and dedication of CSI to resolve problems with their high capacity prototype design. In the late 1990 s a prototype machine, called the Super Gray (Figure 1), was fabricated in an effort to develop a line of planters with increased box carrying capacity. It was hoped that the Super Gray would be an alternative to the current high capacity planter which makes use of an expensive and power intensive roll-back device. The Super Gray prototype did not see immediate success and due to limited resources of the company, the machine was shelved. 2

4 Prototype Machine Creative Solutions, Inc. Fig. 1 The Super Gray Prototype built by Bermuda King. Flail Bars Front Floor Chain Beater Bar Fig. 2 Simplified Model of Prototype Feeding Configuration (side view) The prototype configuration, as illustrated in Figure 2, is composed of a floor chain which slowly feeds the sprig mass into four vertically aligned flail bars. The flail 3

5 bars then attempt to control the feeding rate of sprigs onto the beater bar which in turn distributes the sprigs to the ground. The sprigs are then pressed into the soil with vertical disks. Power is supplied by a tractor through a PTO shaft and into a right angle gear-box. There is no speed reduction in line to the flail bars or beater bar. Speed reduction to the floor chain is accomplished through a variable ring-cone gearbox with a 432:1 minimum reduction and sprockets. Statement of Work Following discussions with Brian Henderson of Bermuda King and Clay Buford of the OSU extension service, the following items are to be considered in regard to CSI s involvement with the Super Gray project. 1) The planter s inability to supply a consistent profile of sprigs to the flail bars. 2) The uncontrollable variability in planting density. 3) A desire to plant between 30 and 1000 bu./ac. at speeds up to 10mph. 4) Bermuda King must be able to manufacture the design solutions in house. The path CSI will take to complete the project will be to analyze the problems in question and develop concepts which will improve the planters performance in these areas, then after selection of the most promising concepts by Bermuda King, design and fabrication of the components will be completed by CSI. Bermuda King is to supply CSI with the Super Gray prototype for testing and modification, in addition to financial support needed for parts, material, and supplies. 4

6 CSI will make all test data, drawings, and any other information pertaining to the project available to Bermuda King. Also, the prototype planter with modifications will be returned to Bermuda King. An oral presentation of CSI s design solution concepts will be presented to Bermuda King in January After discussion and approval by Bermuda King the project will continue through the end of the 2003 spring semester. A full report and final presentation will be delivered in May of Detailed drawings of all design components and modifications will be created. An operator s manual will also be written for proper operation and understanding of the solution. The operator s manual will be easy to understand and will contain any necessary drawings. A finalized prototype will be constructed and presented to Bermuda King in May of The modified prototype s performance should be a marked improvement over the initial design. Design Criteria Many design factors are associated with the solution. The design solution should be compatible with current Bermuda King sprigger designs. A reasonable design budget to solve the problem needs to be established and proposed to Bermuda King. The design budget needs to include a realistic cost estimate of materials, services, and labor involved with the design work and modifications which is not provided by CSI or any other uncompensated source. Dimensional restrictions are limited to the ability of the solution to be safely transported, used, and to be loaded by a front end loader. The dimensions of the solution 5

7 should not exceed the capabilities of Bermuda King to manufacture the solution. All instruments and controls of the solution should be easily understood and operated. All controls should be placed in a convenient and safe location. Warning labels and safety shields need to be placed where possible injury could occur. Testing The project brought to use is one that is not clearly defined. It is known that planting rates are highly variable with this machine but the exact cause of the variability remains a mystery. Therefore, it was decided that the first course of action in developing a solution would be to perform extensive testing on the machine to define problems and formulate solutions. Initial Testing Initial testing was done with the planter as-delivered. The primary purposes of the initial test are listed below. 1. Gain an appreciation for the characteristics of Bermuda grass sprigs and the inherent problems associated with their handling. 2. Gain firsthand experience in the operation of Bermuda King harvesting and planting equipment. 3. Visually observe the planter in operation to gain insight into the problems and possible causes. Two main problems were observed during the initial operation of the machine. The planting rate is very inconsistent both across the width of the sprigger and along the length of a pass, and the top rear portion of the mass of sprigs roll back as the box is emptied. These two problems are closely related, since the planting rate cannot be 6

There is a need for further design analysis and refinement of the flail bars and in the overall metering of the sprigs. The problems described can be easily seen in Figu

8 expected to remain constant when the profile of sprigs offered to the flail bars is not consistent. But providing a consistent profile to the flail bars would not adequately solve the problem of variation in planting rate. There is a need for further design analysis and refinement of the flail bars and in the overall metering of the sprigs. The problems described can be easily seen in Figure 3 and 4. Fig. 3 Note the difference between the two dotted lines. The horizontal line is the desired sprig depth, while the diagonal dotted line illustrates the effects of the sprigs sloughing off of the back of the pile. Fig. 4 In the right picture the lack of consistency in the application of the sprigs is easily seen by the streaking and clumping. 7

9 Floor Chain Measurement and Planting Rate Capabilities Bermuda King suggested a range of planting rates of bushel per acre be considered. To determine the range of the as-delivered planter a series of test were conducted to determine the maximum chain speed available. A spreadsheet was constructed to determine theoretical planting rates based on ring-cone settings and floor chain speeds. Table 1 indicates the capability of the planter as-delivered. The table indicates the highest planting rate to attained is bu/ac while traveling at 5 mph. Gearbox Planting Rates (bu/ac) Setting 5mph 6mph 7mph 8mph 9mph Table 1 Developing a Baseline To quantify the variation in planting density and to determine if future modifications improved that variation, a baseline needed to be developed. To accomplish this the planter was loaded with sprigs, a tarp was placed beneath the beater bar on the ground, the planter was engaged for one minute and the sprig output was collected and weighed (See Figure 5). Data from this test is shown below in Table 2. 8

10 Fig. 5 Second Test Setup Experiment Time (min.) Ringcone Setting Discharge (kg) Table 2 Discharge Rates before Modification After observing six test runs it was determined that some modification was needed to help meter the flow of sprigs through the throat area. The chains powering the second and fourth flail bars were removed to observe results (See Figure 6). The nonpowered flail bars were observed only to have slight rotation during operation. Only two 9

tests were conducted to analyze the results of the modification because sprigs were noticed to jam against flail bar 2. The results are listed below in Table 3. Flail bar 4 Flail Bar 2 Fig.

11 tests were conducted to analyze the results of the modification because sprigs were noticed to jam against flail bar 2. The results are listed below in Table 3. Flail bar 4 Flail Bar 2 Fig. 6 Chains Removed from Flail Bars 2 and 4 Experiment Time (min.) Ring-cone Setting Discharge (kg) Table 3. It was then decided that flail bar 2 needed to be rotated during operation to keep the sprigs from jamming against it. A hydraulic motor was mounted to power the second flail bar by use of a chain and sprockets (Figure 7). An oil flow control valve was connected in series with hydraulic lines running from the test tractor to the motor. 10

A series of tests was first performed to observe which direction of rotation and the rotation rate which would produce the best discharge characteristics.

12 A series of tests was first performed to observe which direction of rotation and the rotation rate which would produce the best discharge characteristics. Counter rotation at 20 rpm was found to produce the best results, and a set of three tests were performed for these settings. These results are posted in Table 4. Hydraulic Flow Valve Flail Bar 2 Fig. 7 Hydraulic Motor Mounting Experiment Time (min.) Ringcone Setting Discharge (kg)

Table 3 Discharge Rates with Hydraulic Motor While this modification did not improve our ability to achieve the target rate, it did decrease the rate variation, thus allowing us to plant a more

Definition of Problems After extensive testing we believe the root cause of all variation in planting rate to be the fact that the flail bars engage varying horizontal depths of sprigs throughout

In comparison to the standard Bermuda King sprigger, the Super Gray throat area is more than 4 time as large, and as a result the floor chain must move at ¼ the speed to achieve the same planting

13 Table 3 Discharge Rates with Hydraulic Motor While this modification did not improve our ability to achieve the target rate, it did decrease the rate variation, thus allowing us to plant a more uniform rate. Therefore, we believe this shows promise as a possible solution. Definition of Problems After extensive testing we believe the root cause of all variation in planting rate to be the fact that the flail bars engage varying horizontal depths of sprigs throughout operation. As a result of the large metering throat area the floor chain must move extremely slow to achieve desired planting rates in the bottom half of the range. In comparison to the standard Bermuda King sprigger, the Super Gray throat area is more than 4 time as large, and as a result the floor chain must move at ¼ the speed to achieve the same planting rate. This creates the actual problem : the flail bars are capable of removing significantly higher rates of sprigs from their rotational area than the floor chain can deliver for most planting rates. Fig. 8 Illustration of Flail Bar Operation The three operation modes of the flail bar are illustrated in (Figure 8). During normal operation only the tip of the flail bar engages and removes and sprigs from the pile as seen in the left image. However, as illustrated in the middle image during initial start up or in rough terrain, the sprig pile shifts forward until stopped by the drum of the 12

14 flail bar which causes significantly higher rates to be momentary planted. The image on the right is the exact opposite of the previous situation. Here the flail bars have previously separated sprigs from the pile which were not in their rotational area, therefore the flail bars continue to run empty until the floor chain moves the pile forward and engage them again. During this situation an initially higher rate is planted as the flail bars remove sprigs outside their rotational area; however planting rate is reduced over an extended period of time until the floor chain catches up. The second problem contributing to rate inconsistency is one which was initially observed by Bermuda King. The height of sprigs in the box decreases as the machine empties causing the effective metering throat area to decrease as well. A smaller throat area and constant floor chain speed result in decreased planting rates. This is partially offset by the fact that some of the change is height is a result of the sprigs settling. As they settle the bulk density of the sprigs in the box increases and thus an equal planting rate can be achieved with a smaller throat area. However, some of the change in sprig height is a result of sprigs falling off the back of the pile as the sprig mass moves forward. This is a contributing factor to the reduced planting rates we observed as the final 10% of sprigs in the box were planted. Solutions Approach Two completely different approaches to developing solutions are possible. One method is to develop a totally new concept from scratch. The other approach is to develop a series of small modifications and adjustments intended to improve the performance of the prototype machine. Due to the scope of this class and the time required to adequately design and fabricate a complete machine, we are concentrating our 13

15 efforts on maximizing the current prototype design. Our goal is to develop a series of mini-solutions which can then be packaged to provide optimal improvement in planter performance. Proposal #1 The first proposed design modification is to incorporate a set of multiple minisolutions. First, we suggest decreasing the flail bar length while increasing the flail bar drum diameter to correct the problems entailed with current flail bar design and its engagement of varying amounts of sprigs. We also believe performance could be improved if the speed of the flail bars were reduced. A moving tailgate could also be incorporated into this design to further increase planting accuracy. Proposal #2 The second proposal is also simply a set of modification to the current machine design. It would consist of utilizing three vertical flail bars to supply sprigs to the bottom beater drum. A slotted cage would be placed over the beater drum and sprig metering would be controlled by the speed of the beater drum. Proposal #3 The third and final proposal is to retract previous statements and investigate a revolutionary new sprigger design not based on the current prototype. This would change the nature of the project into more of an investigation of possible concepts rather than the creation of a fully operational prototype. In the end the decision about which course of action we choose to pursue will be the discretion of Bermuda King and its owners. Currently, we plan to meet with Bermuda King and their management just after the first of the year to discuss the future and direction of this project. 14

Manure Spreader Calibration. Jerry Martin, Senior Extension Associate, Penn State Crop & Soil Sciences

Manure Spreader Calibration. Jerry Martin, Senior Extension Associate, Penn State Crop & Soil Sciences Manure Spreader Calibration Jerry Martin, Senior Extension Associate, Penn State Crop & Soil Sciences 717-394-6851 jmartin@psu.edu Nutrient Management Planning Goals of nutrient management Maximize i profitable