There are several reasons why an ASME-certified vessel may need service. However, the need for ASME R-Stamp Repair is very specific.
Any repairs to the pressures zones on tanks require an R-Stamp. A code repair is when a vessel’s “pressure boundary” needs repair. This could either be a cooling/heating jacket or the tank itself. A ‘non-code’ repair is when the non-pressure area of a tank needs repair.
Troubleshooting Accidents
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. While a scratch may be a non-code repair, any damage to the cooling/heating jacket will require an R-Stamp repair.
Troubleshooting Wear or Failure
Reduced agitator performance or failure is often due to worn parts, improper assembly, or a bent shaft. Agitator repairs may be addressed with the agitator manufacturer or the vessel manufacturer, depending on the situation, down-time, and severity of the failure. If the shaft breaks and causes damage to the “pressure boundary”, the R-Stamp repair will be necessary.
R-Stamp Repairs for Vessel Modifications
Vessel modifications often require an R-Stamp code repair. A new nozzle addition, or any weld to a code ASME vessel may require an R-Stamp repair. Component replacement and shell repairs are typically completed on site by a certified ASME repair service tech. Apache updates R-Stamp forms and are filed with the NB and the customer. A history of all repairs is indicated on the ASME data report.
Getting R-Stamp Repair Support
As mentioned above, It is important to note that any weld repairs to the ASME pressures zones on tanks, require an R-Stamp. 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 factory or field location services including:
• Field service and troubleshooting to all types of stainless and high alloy tanks
• ASME / National Board R-Stamp repair and modifications
• Surface finish repairs
• Non-code repairs and modifications including piping and heat transfer jackets
• Seal and agitation repairs and modifications
• Accessory repairs
• Head and tank shell repairs
• Leak detection
• Audit and service contract available
Visit Apache Field Services if you have an R-Stamp inquiry.
Thermal heat exchange surfaces control the temperature in the vessel and the quality of the contents. 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. In an updated eBook, the Apache team has fine-tuned a guide (link) to explain applications, pressure criteria, and ASME requirements for Conventional Jackets, Dimple Jackets and Half Pipe Coil Jackets.
Conventional Jackets Conventional jackets are an open jacket with an annular space containing the heat transfer media on the exterior surface of the tank. In some instances, internally welded baffles within the conventional jacket control the flow of the heating or cooling agent. In Apache’s experience, water, oil, or heat transfer fluid is typically used as heat transfer agents for conventional jackets.
Variable coverage areas and pressures are available in conventional jacket designs. Dimple Jackets Dimple jackets utilize a thin gauge stainless steel layer that is plug welded to the vessel shell in a regular 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 than a conventional jacket design due to the strength of the dimple pattern design.
Dimple jackets are manufactured in several different pressures and patterns. Apache fabricates with 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 200psig at 300o F but can go to higher temperatures depending on the application.
Half Pipe Coil Jackets The half-pipe jacketed vessel has a split pipe (split evenly or rolled formed sheet) wound around the vessel and welded into place. This design provides optimal strength and can be rated up to 500psig. Half-pipe jackets are recommended for high-temperature and liquid heat-transfer applications.
Material used for half-pipe jackets are commonly 304, 304L or 316 and can be welded to a range of alloys. Sound welding practices allow the half pipe to be welded to high alloys.
Compliance engineering for industries requiring ASME code certification and fabrication is what we do. Dedicated project engineers provide control over calculations, component selection, compliant designs, approvals, testing and certification. Apache has experience and reputation with inspectors, agencies, and governing officials for successful and efficient compliance vessel projects.
Download the eBook “Heat Transfer Surfaces for ASME Vessels” (link) for ASME and application information about heat transfer methods.
ASTM (American Society for Materials and Testing) was developed to set standards for chemical, mechanical, physical, and electrical properties of material, as well as testing standards for materials. ASME (American Society of Mechanical Engineers) includes ASTM standards, AWS (American Welding Society) standards and other nationally and internationally recognized standards as part of a widely adapted design specification for many structures, including pressure vessels.
Apache has substantial capabilities for mechanical and chemical finishing having supplied stainless equipment to hygienic industries for more than four decades. Passivation, pickle passivation and electropolishing processes and associated ASME testing, and processes are 100% in-house. Passivation is the removal of excess iron or iron compounds from the surface of stainless steel by means of a chemical, typically an acid based solution. Unlike pickle passivation, no metal is removed from the surface during the process. The process has little effect on the RA values of the stainless material being passivated.
The ASTM A967 is a passivation standard that applies to the cleaning, passivation, and testing of stainless parts.
Pickle Passivation is the immersion of the metal in a pickling bath or coating the material with pickling solution such as nitric-hydrofluoric acid. The process removes both metallic contamination and heat-treating scales. Pickle passivated stainless steel has a matte appearance. Apache’s tests have confirmed improvements up to 25% in RA readings on material that has been pickle passivated.
The ASTM A380 is a passivation standard that covers cleaning, descaling, and passivating stainless material and parts. Spec A380 may include a variety of treatments, including precleaning, chemical descaling, degreasing and more. Electropolishing is an electro-chemical process that removes surface material from stainless steel. The process includes immersion of the stainless-steel component into a temperature-controlled bath of electrolytes that are charged with a DC power supply. Electrolytes used in electropolishing are concentrated sulfuric and phosphoric acid solutions. The finish has a mirror appearance. Apache’s before and after tests have shown improvements in RA smoothness up to 50%; results vary depending on stainless material.
The ASTM B912 specification outlines the electropolishing process for 200, 300 and 400 series alloys. Spec B912 may include preparatory cleaning procedures, post coating procedures and rinsing protocols. Final testing is also stated in the specification to evaluate performance of finish.
In Guide to ASTM & ASME Stainless Finishes, learn about the mechanical and chemical finishing processes to meet ASME, ASTM and other compliance requirements.
Download Guide
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.
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:
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.
Apache’s background in pharmaceutical, medical, water purification, and chemical industries has driven expertise in high-alloy material used in vessel construction. The process application of a vessel or tank will determine the stainless or high alloy material specified for the construction of the vessel.
Apache’s experience with stainless and high alloy material includes 304, 316, Duplex, Hastelloy, Monel 400, AL6XN, and Alloy 20. Highlighted below is an overview of those applications.
304
304 stainless steel is widely used in food and life science production equipment. The strength, durability, and noncorrosive qualities provide the safety and cleaning effectives required under general conditions.
316
316 has high corrosion resistance and may be used in applications requiring higher strength and hardness. 316 material can be used for fuels, food processing, chemical, medical and pharmaceutical processes. 316 has a higher temperature performance than 314 and performs wells in cryogenic temperatures.
Duplex
The Duplex series are extremely versatile stainless alloys, with many applications in fuel and chemical processing industries and pharmaceutical applications. Duplex has low thermal expansion coefficients and high heat conductivity. In Apache’s experience, the machineability may be more cost effective than 316 L and Hastelloy® material.
Hastelloy®
Hastelloy® has sanitary advantages due to the high Nickel and Chromium content. This material works well for the construction of heat exchangers, columns, and pressure vessels as well as nuclear and chemical reactors. It is used in chemical process equipment applications and high-performance pharmaceutical vessels.
Monel® 400
Monel® 400 is resistant to sulfuric and hydrofluoric acids. Due to the cost, Monel® 400 is only used in applications where other materials will corrode. The copper content of the material prevents an effective pickling finish.
Al6XN®
AL6XN is used in low PH applications in food, oil and gas industries, reverse osmosis, scrubbers, and distillation columns.
Alloy 20
Alloy 20 is used to manufacture pharmaceuticals, food, explosives, chemical and petroleum refinement. It is also used to construct heat exchangers, mixing tanks, and other heat resistance applications.
Apache’s operations and tank team with consult from steel supplier partners have developed a quick reference guide to highlight the composition, corrosion resistance, cost, availability, performance, and applications of the above stainless and high alloy materials. Download our guide here.
The Apache Stainless Equipment Corporation employs experts in the fabrication of stainless and high alloy equipment for a range of industries. Apache is accredited with ASME and more other global standards. By setting service performance for our quality and compliance, we offer value for our compliance engineered equipment.
As a manufacturer of custom vessels for essential industries, including pharmaceutical, life science, and healthcare, Apache provides processors with high-quality vessels with up-front technical collaboration, engineering support, and a solid compliance direction. We bring these 10 tools to Sanitary Vessel customers:
Apache upholds certifications including, 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. In addition to ASME, Apache is accredited in many other global standards.
Depending on the application, processors serving food or other hygienic industries have varying degrees of compliance requirements for custom vessels. When working with your custom vessel manufacturing partner, it is important to identify the level of sanitary compliance in the pre-engineering discovery phase.
Apache defines three categories of sanitary design to help customers with the type of sanitary specifications for construction and fixtures to meet the vessel’s process goals.
BASE LEVEL
The base level sanitary vessel is cleaned manually. Typical construction fixtures include threaded coupling, threaded dip tubes and ANSI flanges. Depending on the application, stock vessels may be used or modified. The material is 2B/Mill, or 304 or 316 stainless and is pickle passivated.
Customers use base-level sanitary vessels for waste tanks, hydrocarbon storage, food-grade applications, adhesives, and solvents.
MID-LEVEL
The type of sanitation is also a driver for more complexity in the design of sanitary vessels. In the mid-level category, components are removed for cleaning or COP (clean out of place).
Mid-Level sanitary vessel designs are constructed with 304 or 316 stainless material and feature mechanical finishing and pickle passivation or nitric passivation.
Sanitary fittings are specified in a mid-level vessel from tri-clamp ferrules and tube connections to NA connects, flush mount outlet valves and sight glasses.
Customers use mid-level sanitary design vessels for material columns, solvent tanks, collection vessels, extraction, expansion chambers, mixing and dispensing.
HIGH-LEVEL
The highest level of sanitary design vessel is automated to be cleaned-in-place (CIP). A 304 or 316 stainless material is specified for high-level sanitary vessels mechanically finished to less than 32RA (roughness average), with nitric and electropolish chemical finish.
The fixtures in this category are electropolished including tri-clamp ferrules, tube connections, NA connects, sight glasses, j-tubes, dip-tubes, and polished internal coils.
Customers using high-level sanitary vessels are involved in automated processing and manufacturing. Applications for high-level sanitary designs include WRI tanks, R&D lab equipment, heating, and cooling vessels and nutsche filters.
Each level of sanitary design can meet ASME UM, ASMEU, FDA, 3-A, CRN, PED, and BPE compliance requirements.
When exploring the project parameters for a custom vessel, our guide, “3 Levels of Sanitary Design Tanks and Vessels” , helps to drive conversations and specifications that will meet the vessel’s application, timing, and compliance requirements.
Apache Stainless Equipment Corporation manufactures stainless equipment for a range of hygienic industries. Apache uploads compliance engineering expertise in beverage, biotechnology, pharmaceutical, cannabinoid, food processing, and life science industries.
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:
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.
Accident
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.
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.
Apache Stainless Equipment Corporation, a manufacturer of ASME pressure vessels, was contracted to provide four (4) large columns for a renewable energy company. Apache’s “Large Vessel” fabricators/ welders manufactured four stainless columns that measured up to 167’ in length, 11’ width, and 112,000 lbs. in dry weight.
Government and public opinion will drive growth in the industry, and Apache is poised to support large tank projects with the staffing, expertise, and facilities to manufacture ethanol and biofuel tanks.
Quality & Compliance
We have a dedicated quality assurance department, including in-house inspectors, that focuses on full verification, testing and compliance documentation. Apache has been ASME certified for over 40 years and upholds many other global standards.
Transport
With company owned transport and dedicated employee drivers, Apache provides general and specialized high and heavy load transportation service. We will manage the necessary permits, escorts, and communication necessary for your large tank transport needs.
Field Services
Apache provides experienced and proficient industry technicians and engineering support to troubleshoot equipment repair and provide ASME and R-stamp modifications. Audio and service contracts are available.
Located in Beaver Dam, Wisconsin, Apache Stainless Equipment Corporation serves the fuel industry with many types of specialized tanks, including distillation columns, evaporators, ASME vessels, API-650 vessels, clad vessels, custom mix tanks and storage tanks.
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