Valmac Industries has been a trusted leader in precision manufacturing since 1985, offering services that set the standard for quality and performance. Among our most valued capabilities is flat lapping, a process that’s essential for achieving exceptional flatness, parallelism, and surface finishes on parts across a variety of industries.
Whether you’re involved in manufacturing components for aerospace, medical devices, or high-performance engineering, flat lapping plays a critical role in delivering parts that meet stringent tolerances. This blog dives into the science of flat lapping, the equipment we use, and the key benefits this process offers.
What is Flat Lapping?
Flat lapping is a precise machining process where parts are rubbed against a flat lapping plate using an abrasive slurry. This abrasion removes material gently and evenly, resulting in parts that mirror the lapping plate’s flatness. A hallmark of this method is its ability to achieve extraordinary flatness and smoothness, measured in helium light bands as fine as 0.000011 inches.
The process is ideal for achieving specifications such as:
- Flatness: Ensuring the surface is even across the entire part.
- Parallelism: Making sure both sides of a part are equally straight and parallel.
- Tight thickness tolerances: Achieving uniform dimensions as precise as 0.0002 inches.
Flat lapping is especially useful for delicate or thin parts, parts with stringent sealing surface requirements, and materials that are difficult to grind using traditional methods.
The Flat Lapping Process
At Valmac Industries, we follow a tried-and-true workflow to ensure flawless results across every project. Here’s a step-by-step breakdown:
1. Preparation of Parts
Parts to be lapped are prepared and placed inside a truing ring, which maintains even contact between the parts and lapping plate.
2. Abrasive Slurry Application
An abrasive slurry of fine particles suspended in a liquid vehicle is dispensed onto the lapping plate. The choice of abrasive (e.g., aluminum oxide, silicon carbide) and liquid is tailored to the material being processed and the desired finish.
3. Lapping Plate Rotation
The truing ring with the parts is placed on the lapping plate. A pressure plate is lowered onto the parts to apply even pressure. The lapping plate then rotates, distributing the abrasive slurry evenly while removing excess material from the parts.
4. Surface Tuning
During the rotation, the truing ring maintains the flatness of both the parts and the plate. This precision ensures parts match the plate’s mirror-flat surface while achieving a consistent finish.
5. Inspection and Finishing
Parts are carefully inspected to ensure they meet the required tolerances. If necessary, further polishing or fine-tuning is performed to achieve enhanced surface finishes, such as reflective or scratch-free surfaces.
Equipment Used at Valmac Industries
We’ve invested heavily in state-of-the-art lapping machines to handle a wide range of part sizes and materials. Our capabilities include:
- Single-Sided Lapping Machines: For processing one surface of a part at a time with incredible precision.
- Lapping Plates: Made from cast iron or specialty composites, these plates provide the perfect foundation for flatness.
- Truing Rings: Essential for maintaining the flatness of the lapping plate and ensuring consistent results across batches.
Our fleet includes machinery with lapping plates ranging from 12 inches to 72 inches in diameter, making it possible to process everything from tiny components to large parts with ease.
Key Advantages of Flat Lapping
Flat lapping provides several unique benefits compared to alternative finishing methods like grinding or polishing:
1. Unrivaled Precision
Flat lapping can achieve flatness values measured in helium light bands and can produce slightly concave or convex shapes when needed. This control is especially critical for parts requiring tight sealing capabilities.
2. Compatibility with Delicate Parts
The gentle material removal process generates minimal heat and mechanical stress, making it ideal for parts as thin as 0.010 inches or those prone to distortion.
3. Versatility in Materials
From standard metals to superalloys, plastics, ceramics, and even exotic materials, flat lapping is effective across a wide range of substrates. Parts that are difficult to grind or magnetically chuck can be easily lapped.
4. Superior Surface Finish
Flat lapping can produce finishes ranging from lightly textured to highly reflective surfaces. With additional polishing, it’s possible to create mirror-like finishes free of micro-scratches.
5. Cost-Effective Processing
With minimal tooling and setup, flat lapping is efficient for both small and high-volume production runs.
Case Studies at Valmac Industries
Sealing Surfaces for Medical Devices
A medical device manufacturer approached us to lap precision sealing surfaces on surgical equipment. The parts required extreme flatness and smoothness to ensure an airtight seal. Using our lapping expertise, we achieved not only their flatness requirements but also a polished surface with a flawless, reflective finish, ensuring the devices exceeded industry standards.
High-Precision Superalloy Components
One of our clients in aerospace manufacturing required flat lapping on turbine blade substrates made from a superalloy. Traditional grinding methods caused distortion and failed to meet flatness tolerances. By switching to flat lapping, we achieved unparalleled precision, ensuring the components performed reliably in high-stress environments.
Trust Valmac Industries for Your Flat Lapping Needs
With over 38 years of experience, Valmac Industries has perfected the art of flat lapping, offering tailored solutions for even the most challenging applications. Our team leverages advanced machinery, technical expertise, and a commitment to quality to deliver exceptional results for clients in diverse industries.
If you’re looking for unparalleled precision, fast turnaround times, and customized service, Valmac Industries is the partner you can trust. Whether you’re sealing the deal on medical components or crafting aerospace-grade parts, we have the skills to make your vision a reality.
Reach out today to discuss your flat lapping requirements or request a quote. At Valmac Industries, precision isn’t just a service – it’s our promise.