There are several important elements of a given spring, and one that plays a big role in determining application type and other factors is the end coil type. Coil ends on a given spring can be aligned in several different ways, particularly within compression spring types that use open-coil designs across several major applications.
At Custom Spring Manufacturing, we’re proud to offer a wide variety of custom spring types, from compression springs to conical springs, flowline springs and many other types. A common end-related requirement for many compression springs is spring flattening, which is often accomplished by grinding the end coils. This is also one of several possible spring finishing types available – today’s blog will go over spring finishing, spring end types and why the grinding process is often used to achieve flat ends for compression springs.
Spring Finishing Basics
As we noted, spring grinding is one of several spring finishing methods available. Spring finishing describes an array of different processes that might be carried out on a given spring to alter its original design, helping it become more useful within a given application.
One example of a spring finishing process is spring coating, for instance, where springs are coated with zinc or some other mineral to aid in corrosion resistance. There’s also strength peening, a spring finishing process that helps springs resist cracking and metal fatigue. Grinding is just one of these processes, one designed to create flat ends on compression springs so that said springs will attach more easily to other surfaces.
Spring End Types
Compression springs have several different end types possible, with flat ends being just one. They may also have open ends, open and ground ends, closed and non-ground ends, and even closed ends that are both squared and ground. Flat compression spring ends will naturally be completely flat, plus will have parallel ends.
Spring Grinding Process
When grinding of a compression spring’s ends to a flat state is required, the process will generally go as follows:
- In most situations, an automatic grinding machine will be used.
- The bushing is fitted into a round plate, leaving a small quantity of spring sticking out of the top and bottom.
- The plate turns itself slowly around, allowing the bushing and spring to pass in between a pair of grinding wheels (or sometimes two pairs in certain machines).
- The wheels grind the ends of the spring to the desired flat state, then drop them into a waiting box where they sit until they can be inspected.
- The spring ends are inspected and tested thoroughly, ensuring they meet both load threshold requirements and proper dimensions for the spring.
For more on spring grinding and flattening of compression spring ends, or to learn about any of our custom springs, speak to the staff at Custom Spring Manufacturing today.