Raymond Die Springs

[Music] Today's modern, efficient Raymond die springs colorcoded to show The work range for which they have been engineered are the products of almost a half century of continuous research and development programs conducted by Barnes Group Incorporated. Before we learn how to select, use and maintain these vital mechanical elements, let us briefly examine some of the basic scientific facts about springs. First of all, what is a spring? It is a device whose function is to store energy elastically. Therefore, any material which has the property of elasticity, that is the ability to return to its original shape and dimensions when forces are applied and removed, may be considered for use as a spring. Materials that have the properties to qualify them under the technical definition are surprisingly varied and cover a truly broad range. It quickly becomes apparent, of course, that the heavy demands put on die springs under shock loading, constant high-speed deflection, heat, and other fatiguing stresses makes the selection of the correct material a matter of the greatest importance. To meet the many demands placed on a die spring, Raymond engineers have standardized on a special analysis electric furnace chrome venadium steel S AE 6150. This tough alloy is another of the reasons why Raymond springs have their famous extra margin of performance. Also of great importance is the shape of the wire from which the helical die spring will be wound. Common from earliest times is the round spring wire cross-section. Although the stress flow in round wire can be controlled, the amount of material for the wire size is not sufficient for optimum load carrying. Putting more material into the space with a square results in high stress concentration in corners and produces a great potential for metal fracture and spring failure. Years of research and testing have resulted in development of the best cross-section for use in Raymond Springs. It is rectangular with rounded corners. This shape allows the greatest amount of material to be packed in the smallest space and provides protection against fractures which result when stresses build up at sharp corners. The optimum material in the form best suited for the application is converted into the industry's toughest springs by specially engineered Raymond machine tools and the skill of experienced Raymond technicians. All of the many manufacturing steps are conducted under strict quality control, inspection, and testing to protect the long service life that has been engineered into every Raymond Spring. Small batch heat treating of springs in furnaces of the optimum design under rigidly maintained conditions assure you the correct Rockwell hardness, the specified steel temper, the exact tensil strength required for the spring's design. Charts and records from this and following manufacturing steps accompany the springs from station to station, giving the batch's full pedigree to Raymond quality control personnel. Under maximum load, ordinary springs will take a set, not return to their original free length, become shorter, and lose their load producing ability. Every Raymond die spring is sent through two remove set operations. This assures you that these springs used within their recommended limits will not fail in operation because of taking set. Both ends of each Raymond spring are ground to provide a reliable flat maximum bearing surface which permits the spring to compress evenly throughout its length. The result is uniform load and stress values in each spring coil. Each is doing its full share and high stress concentrations are not being built up in any single coil. Another reason for Raymond Springs longer life and better performance. Introduced by Barnes Group Incorporated in 1929, this innovation shot peeening of springs cold works and toughens the surfaces, raising the metal's physical strength where stress is highest. Precisely controlled shot peeening is still used to extend the life of highly stressed springs. Springs subject to lower stress levels are treated with a sand blasting process to produce a similar effect. The final production step is the application of a specially formulated colored coating to instantly identify the finished Raymond DPS springs work ring. Before your eyes is a conclusive demonstration of Raymond Dpring superiority. Two springs, Raymond and one of another well-known manufacturer, both identical in size and work range, are compressed in the same manner in the same equipment. Notice that after the other manufacturer's die spring has reached its full travel, the better performing Raymond die spring continues to compress and apply load. The selection of the correct die springs for strippers, pressure pads, and other die components is part of the design function. Don't wait until the tool is built to determine which springs and how many are needed for the job. Some of the spring terminology needed for adequate understanding of diring selection and use are free length, the measurement of the spring before it has been placed under load. Hole diameter, the nominal outside diameter of the spring, actually the size of the hole into which it will nest. Rod diameter, the nominal inside diameter of the spring, actually the diameter of the rod over which it will fit. Preload, the distance the free length of the spring is reduced by the pressure of the assembled tool. Operating travel the linear measurement which is subtracted from the spring length after operating force has been applied. Compressed length the length of the spring after work force has been applied. Barnes Group Incorporated introduced its well-known registered color coding system to give instant visual identification of the springs work range to prevent errors in spring selection and installation. Blue Raymond springs are for medium duty application, red medium heavyduty, gold heavy duty, and green extra heavy duty. The designer should specify springs both by color and work range designations as well as size. The four color-coded ranges are engineered to provide the user increases in load from one group to another yet retain the same physical dimensions such as hole size, rod size, and free length. Raymond die springs offer the designer and toolmaker the industry's widest range of sizes. There are more than 350 different sizes to select from. Each of the four color-coded groups has eight hole diameters and up to 16 lengths. The Raymond diering handbook is a very valuable tool for everyone specifying or using die springs. One method of selecting the correct Raymond springs for the job is to choose from Raymond charts giving the pressure pounds per 1/10enth of an inch deflection and at maximum deflection. Another spring selection method made possible by charts in the Raymond Dring handbook is to work from the amount of operating travel the springs will be subjected to as indicated on the tool drawing. Refer to the handbook and select springs in the correct duty range to operate efficiently at the recommended travel. Calculate the number of springs needed by working with the pressure pounds for a single spring indicated on the chart. A good rule to observe in spring selection is to always make it part of the original design project. Do not wait until after the die is designed to choose springs and decide the number to be used. Always select springs to produce the required load with the least amount of deflection. This will increase the useful life of the spring, reduce the chances of spring failure, reduce downtime, reduce lost production, and reduce maintenance costs. The more rapidly a spring works, the more attention must be paid to its fatigue limits. In slowmoving dyes and tools, it is possible to get good performance with springs operating near maximum deflection. As the working speed increases, the life expectancy of the spring at that deflection decreases. Dyes spring costs are a very small part of the total cost of the die. An effort to save a few cents on die springs is a misguided act that can cost many dollars in lost time and labor. When servicing a die, never replace only part of the number of springs used. Replace them all for balanced performance. It is also wise to replace all of the springs on a regular schedule based on the number of cycles worked as preventive maintenance. The investment is small. The return in trouble-free performance is large. [Music] Raymond colorcoded chrome venadium die springs are your best insurance for spring reliability. Specify them by name, by color, by work range, by size. Specify Raymond die springs. Heat. Heat. [Music]