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Trends in Custom Vessel Manufacturing

In the last few years, Apache’s essential manufacturing customers have faced familiar developments in supply chain and resources. In a round table query of Apache’s sales and engineering team, here are the top 3 post-pandemic equipment trends and resource challenges experienced by our customers. 

1. Solutions to Support Manufacturing Flexibility 

The need for flexible equipment and processing tasks is common among pharmaceutical and biopharma processors working with Apache.  Whether it is customized batch processing or equipment that needs to accomplish more than one task, Apache has met many processing goals with custom sanitary design vessel solutions. 

Apache’s experience in compliance-engineered specialty tanks, including custom mix tanks, jacketed vessels, extraction equipment, columns, and evaporators, manufactured to custom specifications with the expertise of ASME (and other global standards) engineering and control.  

Processors are also leveraging automation to create efficiencies in flexible production.    Automated CIP (clean-in-place) vessels, heat exchange programming, and recipe controls help with automation goals for many manufacturers requiring custom vessel solutions.

2. Nearshoring Partnerships

The pandemic, the Suez Canal disruption, and economic tensions with China have lasting sourcing effects on many industries, which continue to drive businesses to innovate their supply chain strategy.  New customers are prioritizing availability, quality, service, and customization over cost to grow new partnerships with Apache.  

Entire industries are moving toward nearshoring sources. In one example, the semiconductor industry is taking advantage of the CHIPS and Science Act (2022) to help the US regain the lead in semiconductor Chip manufacturing. Apache has been a long-time manufacturer of custom vessels for specialty chemicals used in the chip manufacturing process and is positioned to provide custom vessels to additional partners.  

3. Supporting Customers with Expertise / Services

Affecting every industry are workforce shortages and lack of experience in technical and skilled positions.  As an employee-owned company, Apache can retain experienced employees who work alongside recent graduates rounding out effective teams.  Apache is designing our support strategy to help customers with compliance education and provide a consultative approach on projects to troubleshoot issues before they drive cost or timing. 

Professionals new to industries requiring custom stainless vessels are welcome to read “Design to ASME Submission”, or “Guide to Factory Tests and Certifications for ASME Tanks and Vessels”. Our eBooks and blogs are written to help customers learn about the importance of compliance engineering and manufacturing. 

With a legacy of compliance engineering and manufacturing comes a dedicated quality control program.  Apache has excellent relationships with inspectors, government agencies, and compliance officers to keep your project moving forward.  We have a strong quality assurance team with plant-wide initiatives for continuous improvements.  Our entire company from our compliance and quality engineers to our ASME welders, knows how to facilitate ASME, PED and other global compliance regulations. 

Requirements for the Repair or Alteration of ASME Stainless Pressure Vessels

Whether an accident, environmental damage, or refurbish needs, vessel repair may be necessary at the customer site.  It is important that whoever works on ASME pressure vessels is qualified, certified, and experienced. The National Board, the regulatory commission for ASME, requires an ASME R-Stamp for the repair or alteration of pressure vessels.

Repair areas and welds should be carefully assessed before repair.  Qualified technicians may use die penetrant, x-ray, or ultrasonic devices to inspect welds and surface defects.

If the vessel requires repurposing or refurbishment, qualified ASME engineering professionals must be involved to make sure the changes are compliant with ASME. 

All nozzles and attachments added to the pressure vessel must be ASME compliant.  In addition, there are specific requirements for materials by ASME, including all attachments that are welded to the pressure boundary.

The welding procedure for ASME vessel repair is extensive to include rules for joints, torch cutting, arc gouging, grinding, reinforcement and post weld treatments.

For all repairs or alterations to stainless vessels, it is essential to know the materials and heat treatment requirements. The owner of the vessel, the manufacturer of the vessel, or the National Board (if registered) will have a data report on the vessel which includes a history of all repairs and ASME data for the vessel.

Sufficient time for the proper repair or refurbishment of the vessel is also a requirement.  The tank or vessel needs to be off-line for proper testing, prep, verification, and compliance documentation to be accomplished.  Repair or refurbishment may take a few days to complete, so discuss the plan and process with your repair organization.  Apache provides a realistic timeline estimate after the results of the repair / refurbish assessment. 

Apache Stainless, as a qualified ASME R-Stamp manufacturing organization, will work with the customer, NDE (Non-Destructive Examination) firm (if required) and third-party inspector during the process and will provide the R stamp documentation to the customer and the National Board (NB) when completed.

There are significant requirements for R-stamp approval including:

  • Qualified material documentation
  • Supporting calculations
  • Qualified and certified welder, and welding procedures
  • ASME inspector and witness to R test and attachment of stamp
  • Registering with the National Board.

Apache’s technicians are fully certified ASME welders.  With over 40 years’ experience in vessel manufacturing and continued excellent inspection ratings from ASME auditors, Apache is a solid partner for ASME compliance design, manufacturing, and repair.

Top 3 Indications you Need an R-Stamp Repair

ASME (American Society of Mechanical Engineers) and NB (National Board) certification is an extensive procedure. An R-Stamp repair is required by the NB when the pressure vessel’s barrier is broken. These repairs include, but are not limited to, weld repairs, installation or replacement of nozzles, and attachment of components related to pressure parts. Here are 3 situations that may ultimately require recertification of ASME: 

  1. Pressure boundary failure
  2. Field Modification
  3.  Accident

Pressure Boundary failure

Leaks coming out of the jacket, inlets, or pipes may be a sign that you need repair to the pressure- affected components or zone. 

Examine the insulation cladding weep hole, normally in the lowest area of the cladding, to check for flow of fluid or steam that could be coming from the heating and cooling jacket. This may be the result of a crack or defect in the jacket.

Symptom of increased water, steam, or glycol usage in the process, can occur in all types of ASME U or ASME UM vessels and all styles of jackets (shell, dimple, or half-pipe) as a result of the cracking or defect.

Field Modification

A new nozzle addition, or any weld to a code ASME vessel, for even a ladder bracket, may require a certified R-Stamp repair.

Before any field repair or modification of an ASME pressure vessel, consult the manufacturer or a qualified ASME / NB repair service. As the owner of an ASME pressure vessel, you are responsible for workplace safety and the liability and ASME certification of all repairs.

In extreme cases, unqualified work may result in scrapping the vessel. Material traceability and other ASME processes required for NB filing and certification become difficult to verify and prove.


In some accidents, improper thermal cycling may cause cracking of inlet and outlet areas of piping and cause stress detachment in the welds of the jacket and base material.

A damaged vessel wall or vessel internals from a tool dropping can cause damage to require repairs to a pressure boundary zone.

It is important to update organizational compliance standards, training, and work procedures to assess how damage and safety issues occur to develop prevention measures. 

Whether a pressure boundary failure, field modification, or accident causing the need for repair, the first step is a Repair Evaluation.  When accessible, thermal imaging, dye penetrant examination, or a radiographic inspection can help locate the defective areas. Then an estimate time of job is performed with a schedule for production downtime. Apache’s qualified ASME R-Stamp repair technicians work with an inspection firm for R-Stamp repair. Apache Stainless, as a qualified R-Stamp manufacturing organization, will work with the customer, NDE firm (if required) and third party inspector during the process and will provide the R stamp documentation once complete.

Component replacement and shell repairs are typically completed on site by a certified ASME repair service tech. Apache updates R-forms and are filed with the NB and the customer. A history of all repairs is indicated on the ASME data report.

There are significant requirements for R-stamp approval including:

  • Qualified material documentation
  • Supporting calculations
  • Qualified and certified welder, and welding procedures
  • ASME inspector and witness to R test and attachment of stamp
  • Registering with the National Board.

Apache's Technicians are fully certified ASME welders. For over 40 years, Apache continues to maintain rounds of audits and inspections from ASME compliance and safety professionals that speak to the consistency of the welders and the effectiveness of the quality control department. We hold these certifications: ASME U Certificate, ASME UM Certificate, National Board of Boiler & Pressure Inspectors R Certificate, and National Board of Boiler & Pressure Vessel Authorization to Register Certificate.

10 Reasons Why Ethanol Producers Choose Apache Stainless as Their Tank Manufacturer

1.            The number one reason for partnering with Apache for your ethanol vessel is our expertise of over 40 years supplying tanks for ethanol and biofuel production.  We specialize in heat exchange surfaces, pressure vessels, custom mix tanks, evaporators, and extraction equipment made from stainless and other high alloys. 

2.            Apache has the capacity for specialty large tank projects.  We have custom-designed and fabricated tanks from one gallon to 160,000-gallons.

3.            Apache has a good standing in the community and the technical college to recruit and retain skilled fabricators.  Our welders are ASME certified and are graduates of rigorous step programs and maintain a continuous excellent safety rating.

4.            We have control over advanced manufacturing processes. Our tenured engineering staff is experienced in project management of ASME specialty pressure vessels.

5.            Apache is employee-owned, a culture that drives efficiencies, collaboration, and innovation.  Our employees fully understand that customer satisfaction is directly related to the success of our company.  Located in Beaver Dam, in rural Dodge County Wisconsin, we have a strong midwestern work ethic.

6.            In-House material finishes include robotic and mechanical polishing, pickle passivation (ASTM A380 & A967) Electropolishing (ASTM B912). There is no outsourcing of finishes, Apache handles any size to be polished, passivated, or electropolished.

7.            Apache has a quality assurance team to coordinate testing and processes, TOP packages, and certifications, including ASME U, UM, CE Marking Permission, National Board of Boiler and Pressure Vessel Inspectors, UN DOT, and CRN (all provinces and territories.)

8.            Backed by full ASME and other global standards, Apache offers numerous testing and certification required for compliance, including pneumatic testing, hydrostatic testing, liquid penetrant, saline testing, CIP coverage, base metal thickness, ferroxyl testing, positive material ID, ferrite levels, radiography, and UT weld testing.

9.            Apache has dedicated transportation personnel and a fleet for specialized high and heavy load services.  Our transportation team provides permits, escorts, and communications for large tank loads.

10          Our field service technicians have years of experience as tank fabrication and repair specialists at Apache.  We fully support all stainless and high alloy vessel construction and refurbishment. We are ASME and National Board R-stamp certified for repairs and modifications. Our field service offering can be extended to audit and service contracts for preventative maintenance service preferences.

Sometimes Tank Damage Isn't as Bad as You Think

There are two main causes why a vessel may need service. There is a performance related issue, or there has been an accident.

In the case of an accident, such as a tool falling into the tank and causing damage; surface scratches and dents can typically be repaired on-site, provided they do not go beyond minimum requirements, with mechanical polishing or hand/wand electropolishing. 

The damage might be a bent agitator, or it might be damage to a side wall or baffles.  We see these kinds of things all the time and we can fix them most of the time.
Depending on the size of the vessel and type of repair, Apache’s service techs may be able to make repairs on site or in some cases, tanks are shipped back to the factory. Apache can provide services including:

  • Repair and replace agitator shafts
  • Add agitation to a non-agitation vessel
  • Refurbish outlet valves, seals, or-rings, and gaskets
  • Relocate nozzles and fittings
  • Replace manways
  • Repair jackets (conventional, dimple, half-pipe)
  • Add cooling or heating coils
  • Detect and repair leaks
  • Refinish product contact surfaces
  • Repair sidewalls
  • Change bottom head configurations
  • Modify tanks, platforms, catwalks for repurposing
  • Convert non-pressured vessel to pressurized (if approved by engineering)

It is important to note that any weld repairs to the ASME pressures zones on tanks, require an R-Stamp.  The R-Stamp is a certification required by the National Board of Boiler and Pressure Vessels for repair of an ASME tank or vessel.

Whether you have a critical repair or planned service, you need trained technicians who know how to maintain and refurbish pressure vessels.  Our technicians are ASME certified with confined space training and have the tools and expertise to make repairs and provide consulting on underlying causes of problems to make recommendations for improvements.

Contact Josh Schladweiler, Field Services / Parts Manager to schedule service.

920-356-9900 Ask for Field Services/Parts

Download the Tank Group Field Services flyer

Custom Vessel Design to Compliance - Steps to Success


Designing custom vessels to compliance, such as ASME or CRN, is a highly engineered approach. Certainly, manufacturers of the custom vessel must have required accreditation, but the engineering expertise goes beyond certification. The pressure vessel manufacturer must have experience and a reputation with inspectors, agencies, and governing officials to manage the compliance process smoothly and efficiently.

The process is complex, and we must educate customers about the important steps, all of which affect the project's outcome. The process includes consultation, project engineering, manufacturing, and compliance.


When discussing the intent of the vessel with the Customer or Engineering Firm, the sales team works to learn more about the industry and process that the vessel will serve.  This will often help us make recommendations on design attributes that the customer may not know this early in the design and vessel selection process.  This is especially important in the absence of a formal specification package.

A scope alignment meeting occurs to discuss the proposal and services. This meeting may include revisions, due dates, milestones, review of pricing, terms, and conditions, and certification timelines and deliverables.

Project Engineering

After Apache receives the PO (purchase order), we assign the project to the engineer, and the kick-off meetings begin. Sales works closely with the project engineer to relay information back to the customer.

Engineering will perform final calculations, complete the design, consult with component manufacturers, and review designs with the customer. Construction, pressure, fixtures, and components must comply with ASME or CRN code.

Once the customer approves the design, Apache submits the compliant design to ASME, CRN or other faction approval and begins managing that process.


The project engineer creates detailed drawings for the manufacturing process. Staff, fabricators, and welders are ASME certified. All welders are approved for the weld procedures required to make custom vessels.


Project engineers work closely with manufacturing and quality assurance technicians to conduct the testing required for compliance. ASME testing and certification requirements include pneumatic, hydrostatic, liquid penetrant, saline, riboflavin, CIP coverage, material, base metal thickness, material trace, welder trace, Ferroxyl, PMI (Positive Material Identification) radiography, and UT. Apache provides in-house inspection services, which benefit customers with ASME projects. The documents are provided in the TOP (turnover packet) by Apache's Quality Assurance team.

Apache has been ASME certified for over 40 years. In addition to ASME, Apache is accredited in many other global standards, including CRN.

In addition to the "12 Steps to Compliance" video highlighted in this blog, learn more by downloading our e-book, "Road Map: Design to ASME Submission."

New E-Book: Design to Submission Road Map

Many of Apache's customers, come to us with a full specification outline to custom manufacture their tank or vessel. For pharmaceutical, life sciences and health industries, Apache often works with integrators who add their process technology to sanitary equipment supplied by Apache.  We also provide vessel solutions to end-users who have process technology support or experience, and need a vessel manufacturer to help them meet their quality and compliance standards.

Specifications such as Fixtures and fittings are also part of the compliance engineered solution. When learning about the vessel's intent, we want to define what the process connection (or nozzles) are required, as well as the service for each nozzle. This will help to pre-plan the general layout and placement of the nozzles. For custom ASME or other standards, the nozzles that we use must be compliant-driven and support the pressure/temperature rating of the vessel. 

In this e-book "Road Map: Design to ASME Submission", we offer project planning recommendations for vessels that require ASME or other compliance.  It is especially helpful for engineers or purchasers new to the role of procurement of sanitary custom vessels and tanks.  This detailed "road map" provides planning insight and knowledge to acquire custom-designed and manufactured ASME vessels with an understanding of compliance engineering.

It is very important to partner with a vessel manufacturer with expertise in the type of vessel and industry for the use of the vessel. In ASME applications, it is vital that critical staff, fabricators and welders be ASME certified. Experience as well as reputation are significant when working with inspectors, agencies and governing officials to keep the compliance process moving forward.

ASME is a leading developer of codes and standards in the mechanical engineering community. Apache has been ASME certified for over 40 years.

Read the e-book, and learn more about compliance, engineering and project management to meet goals and procure quality vessels that not only meet compliance standards, but project goals too.


Versatility of Dimple Heat Transfer Jackets

Versatility of Dimple Jacket Heat Transfer Thermal Processing

Apache’s engineers and fabrication experts are entrusted by many national and international processors to provide complex vessels with a host of compliant driven specifications and required quality protocols.  With nearly 45 years of experience providing custom vessels, Apache has significant experience in thermal heat exchange surfaces. 

Heat exchange surfaces can be designed for heating or cooling. Jacketed vessels are used in many industries and can be used to remove the elevated heat of reaction (heat reactor vessel) or reduce the viscosity of high viscous fluids.

Depending on the application, dimple jackets offer versatility in heating or cooling for almost any shape or size of vessel. 

Dimple jackets are constructed with a thin gauge stainless steel layer that is plug welded to the vessel shell in a pattern.  The punched and spot-welded areas are called dimples, which create turbulence of the heating or cooling fluid flowing through the jacket.  The dimple jacket design allows for thinner vessel shell walls compared to a convention jacket due to the strength of the dimple pattern design.

Dimple Jackets are manufactured in several different pressures and patterns. Apache provides both 12 ga. and 14 ga. material. Each pat­tern is validated and proof tested per ASME regulations.

Apache has proofed and certified designs up to 1 ¾” at 290psig at 300o F but can go to higher temperatures depending on the application.  

Applications and Features

  • ASME approval by the National Board of Boiler and Pressure Inspectors up to 290 psig.
  • Pressures of 290 psig with temperature limited to 500 degrees F, depending on the application.
  • High jacket pressures permitted without significant increase of side structure thickness.
  • Efficient heat transfer at low media flow.
  • Dimple jackets are well suited to steam applications.
  • They can be used to provide heat transfer or cooling for virtually any shape or size of vessel.
  • On large tanks, dimple jackets have a lower price point and maintain a higher pressure drop compared to conventional jackets. On small vessels, conventional jackets have a lower price point followed by dimple jacket and half pipe solutions.

Apache specializes in manufacturing custom vessels for high compliance industries including pharmaceutical and bio-pharma. We manufacture specialty sanitary design tanks, including pressure vessels, processing tanks and mixing vessels. We have all Stainless ASME certified manufacturing facility with custom capabilities including heat exchange surfaces, agitation, CIP (clean-in-place) componentry and controls. Apache has an in-house quality and compliance team to provide all testing and documentation requirements.

Learn more about Heat Transfer.

Comparing Base, Mid, and High-level Sanitary Finishes [Infographic]

Categorizing levels of sanitary design is helpful to professionals new to compliance regulated industries requiring custom vessels because it bridges communications regarding standards and design requirements.

In hygienic applications, stainless equipment requires a sanitary finish which generally refers to a smooth, scratch-free, non-corrosive finish.  The fineness of the finish, which determines its performance, is measured in RA (roughness average). The infographic illustrates the RA of different types of mill, mechanical, and chemical finishes.  The smaller the RA reading in microinches (height in millionths of an inch), the smoother the finish. 

When collaborating to qualify a project, we define a Base Level Finish as a 2B/Mill, 304 or 316 stainless materials that is pickle passivated.  The welds are continuous and crack and crevice-free.  This type of finish is paired with a Base Level Sanitary Design and is cleaned manually. Apache’s standard portable vessel line are an example of the base sanitary design and finish level.

A Mid-Level Finish is also composed of 304 or 316 stainless material and involves a secondary process of mechanical polishing greater than 32RA, with final finishing to include pickle or nitric passivation. The welds are continuous, crack and crevice-free, and are also ground flush and polished smooth to a specific RA.  Sanitary fittings, mechanical polishing, additional passivation processes and a cleanable design with removable components are categorized as Mid-Level Sanitary Design features.

Providing the smoothest RA readings is an electropolished finish after a series of processes, including mechanical finishing to less than 32 RA, passivation, and nitric passivation, which are common for High-Level Finishes.  The base material is 304/316 stainless. The welds are continuous, crack and crevice-free, ground flush and polished smooth to a specific RA designation less than 32RA.  The sanitary fittings are also electropolished.  Vessels with this level of specifications are typically cleaned automatically.

The specifications, construction and finishing of a vessel is often driven by standards and compliance requirements. All three categories, qualify for ASME UM, ASME U, FDA, 3-A, CRN, PED, BPE.

There are other factors that fall in these base, mid and high-level sanitary design categories, including construction features, processing applications and time to delivery.  Download our e-book “Guide to Sanitary Design for Custom Vessels in Hygienic Industries".

Anatomy of a Sanitary Design Vessel

When evaluating a custom vessel manufacturing partner for a new project, consider the manufacturing capabilities and experience that support the vessel’s application and sanitary requirements.

All custom design stainless vessels for the food, life sciences, pharmaceutical and health industries require sanitary construction. It is the application and automation that drives the level of sanitary componentry.

In reviewing each new custom vessel project, Apache identifies the sanitary requirements to categorize the vessel into a base, mid- or high-level design.  Apache offers a standard line of vessels that qualify for various regulatory compliance agencies.  However, these designs are considered a base level sanitary design, especially because the cleaning of the equipment is manual.  Apache identifies a mid-level sanitary design vessel as having COP (Clean Out of Place) components.

In the video, a custom vessel is animated to walk through characteristics and examples in the highest and most automated level of sanitary design custom vessels.

High-Level Sanitary Design Characteristics Include:

  • CIP (Clean in Place) Process and Components
  • Continuous, crack and crevice-free welds, ground flush and polished smooth to specific RA (Roughness Average) <32 RA
  • 304 or 316 stainless material, mechanically finished to <32 RA
  • Electropolished and Nitric passivated finishing
  • Electropolished sanitary fittings, including:
    • Tri-clamp ferrules
    • Tube connections
    • NA Connects
    • Flush mount outlet valves
    • Sight glasses
    • Orbitally welded j-tubes
    • Dip-tubes
    • Polished internal coils
    • Samples Ports
    • Spray devices
    • Control panels
    • External thermal jacketing

Processes and application in high-level sanitary design vessels include heating and cooling vessels, mixing and processing tanks, WFI tanks, filtering and R & D lab equipment.

Certification requirements is an important part of the sanitary design criteria.  Sanitary design standards include:

3A – A regulation of the design for processing equipment in the food and drug industries. A 3A certificate is proof of FDA compliance.

ASME U and ASME UM -  A regulation of the design of boilers and pressure vessels, including traceability of materials, procedures, testing and documentation.

BPE – A standard within ASME that drives equipment design for the bio-processing, pharmaceutical and other hygienic required industries.

In qualifying design, safety, automation other application details, Apache will facilitate the required compliance for the vessel and provide well communicated delivery, cost and approvals required for a successful project.

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