C4 Welding
C4 Welding was a Sauk Rapids, Minnesota-based precision welding and machining manufacturer offering ASME-certified pressure vessel fabrication and contract manufacturing services to industrial customers. It was acquired by Millerbernd Manufacturing in May 2025 and now operates as Millerbernd Circular Products.
- Company typePrivate
- Founded1983
- HeadquartersSauk Rapids, United States
- Headcount101–250
- GTM typeB2B
- OfferingHardware or Manufacturing
What C4 Welding does
C4 Welding was a privately-held precision welding and machining manufacturer founded in 1983 and headquartered in Sauk Rapids, Minnesota, operating a 154,000-square-foot production facility with a workforce in the 101-250 employee range. The company specialized in certified precision welding, machining, and ASME-certified pressure vessel fabrication, serving industrial manufacturing customers across sectors including Department of Transportation infrastructure, mining, construction, wind energy, rail, and HVAC. Its core capability base was conventional heavy-industrial metal manufacturing, anchored by ASME certification that allowed it to bid on pressure vessel work requiring strict quality and safety compliance.
C4 Welding generated revenue through direct B2B sales of custom manufacturing services to industrial customers, with project-based quoting tied to specifications rather than standardized product pricing. Its go-to-market was sales-led enterprise engagement with no disclosed marketing channels, software platform, or app-based distribution. The customer base was vertical-focused on industrial manufacturers needing certified welding and machining capacity. Pricing was not publicly disclosed, consistent with the B2B contract manufacturing model.
On May 15, 2025, C4 Welding was acquired by Millerbernd Manufacturing, a Winsted, Minnesota-based leader in DOT traffic and lighting infrastructure and circular product solutions. Following the acquisition, the Sauk Rapids facility was rebranded as Millerbernd Circular Products, all C4 employees were retained, and the combined entity expanded its portfolio to include ASME-certified pressure vessels alongside rings, circular weldments, rolled plate, and airfield ground lighting products.
C4 Welding firmographics
Firmographics- Name
- C4 Welding
- Legal name
- C4 Welding
- Website
- https://c4weld.com
- Company type
- Private
- Founded year
- 1983
- Operating status
- Acquired
- Headcount range
- 101–250 employees
- Short description
- C4 Welding was a Sauk Rapids, Minnesota-based precision welding and machining manufacturer offering ASME-certified pressure vessel fabrication and contract manufacturing services to industrial customers. It was acquired by Millerbernd Manufacturing in May 2025 and now operates as Millerbernd Circular Products.
- Ownership category
- akta.pro rank
C4 Welding industry classification
Industry- Product category
- Industrial Welding & Machining / Pressure Vessel Manufacturing
- SIC
- Miscellaneous Fabricated Metal Products (3490)
- akta.pro primary industry
- Welding, Fabrication & Field Machining Services (On-site) (IMAIACAD)
Keywords
Where C4 Welding is headquartered
LocationHeadquarters
- HQ city
- Sauk Rapids
- HQ country
- United States
- HQ region
- North America
Offices1 record
Markets served
C4 Welding business model
Business model- GTM type
- B2B
- Offering type
- Hardware or Manufacturing
- Cost components
- Personnel, Operations, Supply Chain, Infrastructure
Revenue model
- Precision Manufacturing Services: C4 Welding generated revenue through precision welding and machining manufacturing services for industrial customers. The acquisition expanded Millerbernd's circular products portfolio with ASME-certified pressure vessels.
Go-to-market motion1 record
Distribution channels1 record
C4 Welding product offering
Product offeringCore offering
C4 Welding is a certified precision welding and machining manufacturer that produced ASME-certified pressure vessels, circular weldments, and related fabricated steel components for industrial customers. The company operated a 154,000-square-foot manufacturing facility in Sauk Rapids, Minnesota, and now operates as Millerbernd Circular Products following its May 2025 acquisition by Millerbernd Manufacturing.
Product overview
C4 Welding is a certified precision welding and machining manufacturer that was acquired by Millerbernd Manufacturing. The company operated a 154,000-square-foot facility in Sauk Rapids, Minnesota. The acquisition added greater capability and capacity for circular products and ASME-certified pressure vessels to Millerbernd's portfolio. All C4 workforce was retained, and the facility continues operation under the name Millerbernd Circular Products.
Differentiator
Problem solved
Functional benefit
Products and services
- Precision Welding and Machining Services Certified precision welding and machining manufacturing services for industrial customers, including ASME-certified pressure vessels and circular products. Sold to B2B industrial buyers in DOT infrastructure, mining, construction, wind energy, rail, and HVAC.
Companies that use C4 Welding
Customer profileNamed customers1 record
Segments1 record
Ideal customer profiles1 record
C4 Welding technology and API
TechnologyTechnology focussed No
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature1 record
C4 Welding partnerships and signals
Strategic signalPartnerships
One partnership is on record.
- MillerberndcoreMillerbernd Manufacturing acquired C4 Welding in May 2025, integrating the company's 154,000-square-foot precision welding and machining facility into its operations. The acquisition adds greater capability and capacity to Millerbernd while expanding the company's portfolio with diversification in circular products and ASME-certified pressure vessels. All C4 employees retained employment as facility rebranded as Millerbernd Circular Products.
Scale indicators1 record
Recent moves3 records
Expansion highlights4 records
C4 Welding competitors and assessment
Company assessmentDirect peers
- Mayville Engineering Company (MEC): MEC is a large U.S. contract manufacturer providing metal fabrication, welding, machining, and coating services to industrial and commercial markets — a closely comparable operating model to C4 Welding's precision welding and machining services.
- Chart Industries: Chart designs and manufactures engineered pressure vessels, heat exchangers, and process equipment for industrial and energy applications — directly comparable to C4 Welding's ASME-certified pressure vessel manufacturing capability.
- Weldship Corporation: Weldship is an ASME-certified manufacturer specializing in pressure vessels and welded fabrications for industrial customers — a niche peer overlapping directly with C4's core ASME-certified pressure vessel offerings.
- CIRCOR International: CIRCOR manufactures flow control products including engineered pressure vessels, valves, and fittings for industrial markets — overlapping with C4's ASME-certified pressure and fluid containment fabrication work.
Broad incumbents
- Standex International: Standex is a diversified industrial manufacturer with engineered products and fabricated metal components across multiple verticals — comparable as a broader incumbent operating in precision fabrication markets C4 serves.
- Mueller Industries: Mueller manufactures copper, brass, aluminum, and plastic products including fittings and fabricated metal components for industrial markets — a broad incumbent competing in adjacent fabricated metal product categories.
- Arcosa: Arcosa produces engineered structural steel products, towers, and fabricated metal components for infrastructure and energy markets — overlapping with C4's industrial fabrication customer base, particularly DOT and wind energy.
- Precision Castparts Corp: PCC (a Berkshire Hathaway subsidiary) is a major diversified manufacturer of complex metal components and fabricated assemblies for aerospace, power, and industrial markets — a broad incumbent at significantly larger scale than C4.
- Ampco-Pittsburgh: Ampco-Pittsburgh manufactures specialty rolled metal products and forged steel components for industrial markets — a broad incumbent with overlapping fabricated metal manufacturing capabilities.
Others
- Kennametal: Kennametal is a leading supplier of metalworking tools, tooling systems, and wear-resistant solutions used in welding and machining operations — adjacent as a tooling and consumables supplier to C4's metalworking processes.
Market position
Strengths4 records
Weaknesses4 records
Competitive moat4 records
Key risks5 records
Key highlights6 records
Customer concentration
C4 Welding social profiles
Digital presenceC4 Welding compliance and trust
Trust signalCompliance1 record
C4 Welding financial estimates
Financial estimateRevenue estimate
Valuation estimate
C4 Welding leadership team
Management profileNumber of profiles
C4 Welding funding detail
Funding detailFunding overview
Funding rounds
Investors
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
C4 Welding M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about C4 Welding
What does C4 Welding do?
C4 Welding is a certified precision welding and machining manufacturer that produced ASME-certified pressure vessels, circular weldments, and related fabricated steel components for industrial customers. The company operated a 154,000-square-foot manufacturing facility in Sauk Rapids, Minnesota, and now operates as Millerbernd Circular Products following its May 2025 acquisition by Millerbernd Manufacturing.
When was C4 Welding founded?
C4 Welding was founded in 1983. It employs 101 to 250 people.
Where is C4 Welding based?
C4 Welding is headquartered in Sauk Rapids, United States, in the North America region.
How does C4 Welding make money?
One revenue line is on record: precision Manufacturing Services.
Who are C4 Welding's main competitors?
Direct peers on record are Mayville Engineering Company (MEC), Chart Industries, Weldship Corporation and CIRCOR International. Broad incumbents are Standex International, Mueller Industries, Arcosa, Precision Castparts Corp and Ampco-Pittsburgh. Kennametal is listed as an others.
Does C4 Welding have an API?
No public API is recorded for C4 Welding.
What industry is C4 Welding in?
C4 Welding's product category is Industrial Welding & Machining / Pressure Vessel Manufacturing. Its primary akta.pro industry code is IMAIACAD, Welding, Fabrication & Field Machining Services (On-site). Its SIC code is 3490.