Reliable manufacturing services are imperative to ensure the quality of the finished product adheres to industrial standards. Quality control and stringent manufacturing processes are followed to produce parts and components that can deliver success in the customer’s project performance and bottom line. 

Fortunately, Grand Valley Mfg. Co. is an experienced manufacturing company offering top-tier services that are second to none. We have an unparalleled commitment to delivering results for our customers..

Our Capabilities

Our team has decades of experience in various manufacturing capabilities, making us one of the best manufacturers of many different products in the industry today. We can consistently deliver top-notch products through our experience, highly refined processes,  and attention to detail.

We specialize in the following capabilities:

Deep Hole Drilling and Trepanning

Deep hole drilling is a process where holes are drilled deeper than their diameter and are often defined by their depth-to-diameter ratio. These holes are typically deeper than 10:1, so they’re considered deep holes. It has many applications across industries, especially when tight diameter control and straightness are highly regarded.

Different materials can be used in this process, ranging from aluminum to super-alloys. However, choosing the right one is essential to ensure they’re compatible with its intended purpose to prevent mechanical failure.

Typical applications of deep hole drilling:

  • Weapon Systems
  • Gun Barrels
  • Fluid assembly ends
  • Heat exchanger tube sheets
  • Aircraft landing gears
  • Hydraulic cylinders
  • Oilfield exploration equipment

On the other hand, trepanning is also a process that creates larger hole diameters. This process is less energy-consuming compared to the traditional drilling method and returns a “core” of usable material from the inside of the solid part after processing. This is especially attractive when using expensive materials like titanium or nickel. Typical applications where trepanning is employed:

  • Offshore Oil & Gas components
  • Gun barrels
  • Commercial Landing Gear
  • Parts requiring “large” inside diameters from solid material

Due to its remarkable properties, trepanning is utilized in numerous industries, such as aerospace and defense, oil and gas, machinery and heavy equipment, and many more.

Turn Services

We offer two types of turning services: manual and CNC turning. Both have unique advantages and should be employed based on the customer’s requirements.

In manual turning, an operator constantly supervises the equipment used, called a lathe, to manufacture the product. A cutting tool is used to shape the rotating workpiece during this process. It’s the best option for parts requiring intimate finesse of sizes and tolerances by a skilled machinist and also useful for removing large amounts of rough stock prior to downstream processing.

Why opt for manual turning?

  • Faster process.
  • Cost-effective compared to other machining processes.
  • Faster turnaround with quick response.

Meanwhile, CNC turning utilizes a computer numerical control system to machine the workpiece. This process is more accurate and provides higher precision than manual turning. It’s suitable for mass production as it allows more excellent repeatability while staying consistent with its results.

In this method, the program is loaded into the CNC work center, instructing the tools to operate according to the given specifications.

Why opt for CNC turning?

  • Provides greater accuracy and consistency
  • Ideal for larger volumes

Mill Turn Machining and Automation

A mill-turn machine is a hybrid CNC machine that combines the tool rotation of milling and the workpiece rotation of turning. It’s a powerful, fast, and flexible machine, completing complex operations faster with better accuracy than other methods.

With both functionalities combined, machined parts and components can be manufactured without delays. More tooling operations can be achieved in a single setup, reducing the  amount of handling and labor time.

  • Typical applications of Mill-Turning: Aerospace and Space Components
  • Power Generation Shafts
  • Locomotive Crank Shafts
  • High-volume component manufacturing

Deep Hole Boring

Boring refers to enlarging the pre-existing hole on the workpiece. This method also can create closer tolerances and higher-quality finishes than drilled holes.

Applications where deep hole boring is used:

  • Engineered Hydraulic Barrels
  • Ship ShaftsCoolant channels in large engines
  • Gun Barrels
  • Ingot Molds
  • Any part requiring an inside diameter


Honing refers to a machining method that produces a highly-precise surface of a workpiece using an abrasive honing stone. l, which is moved  on a controlled path. Honing a metal product can enhance its surface finish while aiming to achieve the final, close-tolerance size.

It’s also used to refine the surface finish of the holes created after the drilling and boring processes. Furthermore, honing is a micro-finishing method utilized to obtain correct inside diameter dimensional accuracy.

Some applications of honing:

  • Hydraulic Cylinders
  • Landing GearBearing Sleeves
  • ID’s with mismatch after drilling 


The conventional milling method employs the use of a CNC Mill I. Like CNC turning, a computer numerical control is also often utilized to control the machine.

CNC Milling is commonly used in machining “block type” parts and components, especially with complex geometries. 

Applications of CNC milling:

  • Subway Car Frames
  • Shaft type components requiring bolt circles or “off center” features
  • Navy Ship Components

Stress Relieving

Stress relieving is a heat treatment process that removes stress from a workpiece accumulated from prior manufacturing processes. Stress-relieving a metal involves subjecting it to a constant temperature below its critical temperature. After that, it undergoes controlled cooling for even distribution and reduces the risk of cracking and warping.

Drawing, forming, and manufacturing can induce stresses in these materials. Because of that, stress relieving is often necessary to improve the part’s metallurgical structure and/or machinability. This process can also enhance its fatigue strength. 

Other processes that induce stress in materials:

  • Rolling
  • Bending
  • Shaping
  • Deformation
  • Casting
  • Welding


It involves manually or under CNC Control, checking the finished parts to ensure they meet the specifications, tolerances, and requirements per the customer’s requests. Part inspection can be conducted while the part is running with the use of “Probing” to adjust the machine in-process. 

In addition, inspections are done to ensure the quality, consistency, and to verify process control and, ultimately, customer satisfaction. We guarantee that all parts are appropriately checked for flaws, imperfections, or non-conforming dimensions. It helps us identify any areas of improvement and ensure complete customer satisfaction.

Other benefits of part inspection:

  • Avoid unnecessary reengineering/re-manufacturing work
  • Confirms quality verification
  • Verifies part traceability and material provenance. 

Choose Grand Valley Mfg. Co. to Fulfill Your Manufacturing Needs

With our long list of capabilities, you can trust us to manufacture your desired parts accurately. We strive to deliver consistent results, which is why many global leaders choose us to manufacture products that meet their expectations.

If you have any questions about our services, feel free to contact us today. You may also request a quote, and our team will find the best solution to meet your requirements. We look forward to hearing from you!