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Versatility of Dimple Jacket 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 200psig 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 250 psig.
  • Pressures of 250 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.


Navigating Stainless Material and Finishes for Hygienic Vessels

Stainless Finishes for Hygienic Vessels are measured by an RA (Roughness Average) meter.  Manufacturers of custom vessels for life science, health and pharmaceutical industries adhere to strict design parameters to maintain compliance in these industries. The RA is a standard for an average of peaks and valleys on the metal’s surface, measured in microinches.  Here is the evolution of stainless material coming to Apache with RA designations as it is transformed into custom sanitary design vessels:

RA > 100 Mill Finish  A Mill Finish has an unpolished, dull-gray, matte appearance. This material type is the basis for supply for all stainless-steel flat products as well as the basis for additional finishing operations.  It is hot or cold rolled with an RA (Roughness Average) of more than 100 microinches, depending on the gauge of the material. 

RA 15 – 40 2B Mill Finish  2B Mill finish is widely used in food, chemical and pharmaceutical equipment applications. It is corrosion resistant and has a typical RA range of 40 (7 gauge) to 15 (16 gauge) microinches.

RA 29 – 58 No. 3 and No. 4 Finish  Mechanical polishing achieves these finishes. The No. 3 Finish uses a 120-grit abrasive and has a semi-polished finish with an RA range of 36 – 58 microinches.  The No. 4 Finishes uses a 150-grit abrasive and has a polished, brushed surface.  The RA range is 29 – 40 microinches.

RA 18 – 31 No. 4A  Also identified as No. 4 Dairy Finish, this finishes is required to meet the basic FDA 3-A standards. It uses a 180 grit and has a RA range of 18 – 31 microinches.

< 32 RA Pickle Passivation   Pickle Passivation often follows other manufacturing processes including welding and grinding. Also called Pickling, it 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.

Lowest RA Electropolishing Electropolishing is an electro-chemical process that removes surface materi­al from stainless steel. The process includes an immersion of the stainless-steel component into a temperature-controlled bath of electrolyte that is 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/after tests have shown improvements in RA smoothness up to 50%; results vary depending on stainless material.

In the highest level of sanitary design applications the vessel is pickled after manufacturing and polishing, then electropolished.


What's Right for my Operation: Pressure v. Vacuum Closures


Vacuum or Pressure closures for small/portable ASME vessels

Many processors come to Apache for a vessel solution in the incubation stage of their business.  In some cases, they are looking for help to choose the right kind of vessel that will suit their needs and fit their budget.  While Apache provides custom ASME vessels for a range of industries, we also offer a line of standard vessels that often solve what these manufacturers need for their process.

The use of the vessel will determine whether it is a pressurized solution, non—pressurized or vacuum vessel solution. 

Vessels that require a minimum of 50 PSI, utilize a pressure closure.  Numerous applications, including heating or cooling process, containment, and pressurized dispensing often utilize pressures at or above 50 psi. 

It is important to note the safety and ASME requirements for pressure vessels, an ASME UM-mark is required for:

  • Vessels 5 cubic feet of volume or smaller with pressures not exceeding 250 psi.
  • Vessel 3 cubic feet of volume or smaller with pressures not exceeding 350 psi.
  • Vessels 1.5 cubic feet of volume or smaller with pressures not exceeding 600 psi.

For vacuum requirements or non-vacuum applications, such as a storage vessel or collecting vessel, a vacuum closure may suit the application.

In the video, Nick Buchda, Apache’s Small Vessel Representative, demonstrates vacuum and pressure closures on our standard line of vessels.

Apache has produced stainless vessels with ASME certification for over 45 years, with other accreditations for pharmaceutical, life science and health industries including ASME UM, ASME U, FDA, 3-A, CRN, PED and BPE. 

Whether the vessel needs fit a standard vessel, modifications to a standard vessel or a custom solution, Apache has the experience to fulfill a range of critical, sanitary-design vessel solutions.


Round Up on ASME Marks

ASME is a leading developer of codes and standards in the mechanical engineering community. These standards enhance public safety and health as well as promote innovation.

The ASME (American Society of Mechanical Engineers) mark is a single certification marketing to signify the international mark of safety and quality. Recognized worldwide, manufacturers that provide ASME have a rigorous quality program, and a third-party review to authorize the use of the mark.

 

The U mark certifies that the pressured tanks or vessel conforms to the latest edition of the ASME code and that the pressure vessel has been designed and manufactured in accordance with ASME.  All aspects are approved by a Third party ASME Authorized Inspector (AAI). U stamps require an ASME inspector to witness the ASME hydro test.

Companies with a U mark undergo a review with the National Board every three years.

The UM mark certified that the pressure vessel or tank conforms to the latest edition of the ASME code and that the pressure vessel has been designed and manufactured in accordance with ASME. The UM vessel’s designation is related to the size of the tank/vessel.

  • Vessels 5 cubic feet of volume or smaller with pressures not exceeding 250 psi.
  • Vessel 3 cubic feet of volume or smaller with pressures not exceeding 350 psi.
  • Vessels 1.5 cubic feet of volume or smaller with pressures not exceeding 600 psi.

While the American Society of Mechanical Engineers writes the rules for the new construction of pressure vessels and tank, the National Board of Boiler and Pressure Vessel Inspectors write the inspection code for new and repaired vessels.

The National Board of Boiler and Pressure Vessel Inspectors require a Certificate of Authorization and R stamp for the repair or alteration of boilers, pressure vessels and other pressure retaining equipment.

Apache has been ASME certified for over 45 years. In addition to ASME, Apache is accredited in many other global standards. By setting parameters for quality and compliance, we offer greater value for our custom stainless ASME tanks and vessels.


12 Engineering Steps to Ensure ASME Compliance for Custom Vessels

Custom vessel manufacturing to industries requiring compliance is what we do. There is a process for customer service and engineering that is required to get the custom vessel you require for your application. There are numerous specifications that will be required based on your process or level of compliance. Apache will work with you to explain and provide options in your vessel project. This collaborative effort will have to control cost and expedite timing for your custom vessel. 

Here are our 12 Project Engineering Steps to Ensure Vessel Compliance:

  1. Understand the intent of the vessel.  Apache has 45 years of experience manufacturing custom vessels.  We can lead important project planning discussion if we know the intent or type of process in which the vessel will be used.
  2. Ensure and Verify Design Conditions.  At this step, our project engineers look at the design conditions, process, temperatures, ASME and other compliance requirement and perform initial calculations.
  3. Determine Finish Requirements. Once design is verified and viable, the project is examined for mechanical and electropolishing requirements, as well as access needed for fixtures and how that has an impact on the fittings.
  4. Final Calculations.  In this step, the engineer provides final calculations to address issues, verify material thickness and fit of fittings.
  5. Completion of Compliant Design.  The ASME/PED/CRN compliant design is completed in 3D Solid Works.
  6. Order long lead time components.  The long lead time components such as the mixer, body flanges, heads are ordered. The supply chain is monitored carefully for timing, and any changes are communicated that may affect delivery.
  7. Component Manufacturer Collaboration.  Apache leverages long term relationships with component manufactures to customize specifications to meet the needs of the process.
  8. Custom Approval.  The customer receives approval drawings with 2D, 3D models.  There is often a series of collaborative meetings to finalize the design and approval.
  9. ASME (or other faction) Submission.  The final design is submitted for ASME or other compliance agency for approval.  Apache also leverages long-term relationships with regulatory agencies to help facilitate a smooth process.
  10. Detailed Drawings.  The engineering team completes the detailed drawings for the manufacturing process and fabrication can begin.
  11. Tests / Certifications.  ASME tests are scheduled and performed by our Quality Assurance team to comply with the certifications required for the vessel.
  12. Turn-over Packet (TOP).  The documentation packet can be completed after the vessel is manufactured and the TOP is developed and uploaded to our customer portal.

Apache’s engineering team articulates technical discussions and is open with timelines, cost and compliance-related issues. Our competence for a pharmaceutical or life science industry vessel is strongly supported in providing all compliance related deliverables.


VIDEO: The Affect of Manufacturing Processes on Stainless Surface Smoothness

The particular RA (Roughness Average) value is a requirement for stainless vessel manufacturing for federal, state or local compliance agencies across many critical industries. It is a crucial standard in these industries to maintain a clean system. The instrument used in the measurement is called a profilometer, which provides an average in micro inches. The smaller the number, the smoother the stainless material. It is common for high compliance vessels to have single digit RA readings on product contact surfaces.

In the construction of pharmaceutical, life sciences, or medical-use vessels, meeting the RA requirement may include several steps, including material selection, grinding, polishing and chemical finishing. Manufacturing processes can affect the RA measurement on stainless material, including forming, stamping and welding. In the video, we walk out of the manufacturing plant with our quality controls manager to show measurements on material in vessels being manufactured in various stages of production. 

Pickle Passivation and Electropolishing chemical finishes have a high degree of improvement on RA smoothness compared to material before it is treated. Pickle passivation, also referred to as descaling, removes the scales and leaves a clean matte finish, free from contamination. Electropolishing is an electrochemical process that dissolves surface metal, removing all embedded contaminants and creates a smooth, mirror finish. 

ASTM International (American Standard for Testing and Materials) is one of several standards that Apache upholds. ASTM A967 is the standard specification for Chemical Passivation Treatment for Stainless Parts. ASTM B912 is the standard specification for electropolishing stainless steel alloys. The ASME-Bioprocessing Equipment (BPE) standard was created for the pharmaceutical and bioprocessing industry. The BPE surface finish standard classifies surface finishes and the acceptance criteria for compliance. 

In the business of compliance vessels, there are numerous standards that are required to deliver the necessary codes in any given project. Follow our videos, blogs and e-books developed specifically to help our processing customers understand the manufacturing and compliance process.


Video: 3 Levels of Sanitary Construction

Processors serving food or hygienic industries have varying degrees of compliance requirements for custom vessels solutions.  The designation of "sanitary" has a wide range of definitions depending on the customer, the industry or the standard.  

This video is a brief overview how Apache defines a base, mid, and high-level sanitary vessels.  

Apache Stainless Equipment Corporation is a manufacturer of stainless equipment for a range of hygienic industries, including, food, beverage, biotechnology, pharmaceutical, cannabinoid, and life sciences.

A dedicated quality control and compliance team directs all tests, certificates and documents for all sanitary, ASME, and global standards.


ASME Stainless Vessel Construction Parameters for Hygienic Vessels

 

ASME (American Society of Mechanical Engineers) is a leading developer of codes and standards in the mechanical engineering community. ASME code section VIII details mandatory rules regarding vessel design, including engineering, manufacturing, and testing of pressure vessels.   These standards enhance public safety and health as well as promote quality and innovation.  Here are the main parameters outlining ASME construction of pressure vessels with supporting ASME testing requirements.

Construction
Parameters such as wall thickness, material, and flange rating are determined by the application, including pressure, temperature, corrosion allowance, and fluid flow.  These conditions are calculated and reviewed/approved by the ASME inspector when required per code. Stainless, Hastelloy, AL6XN, duplex, and Inconel materials are ASME-approved materials for pressure vessel construction in the pharmaceutical, life sciences, and health-related industries, of which Apache is qualified to fabricate.

Welding

ASME standards also define the quality, type, and finishing of the welds. Head styles (ASME F&D, 80:10, 2:1 Elliptical), seams, nozzles, manways, and other components are designed per ASME Code. Applicable ASME Code welding procedures must be followed using certified ASME welders to maintain the structural integrity of an ASME pressure vessel. Welders must be certified to a qualified weld specification qualified per ASME code guidelines.

Safety Components
Gauges, valves, pressure outlets, and drainage are required safety components in ASME design pressure vessels. The proper selection of components and design is critically important to the safety and performance of the ASME vessel. The selection of safety components needs to be evaluated closely to define the required scope of supply.

Finishing
There is another ASME specification to ensure the quality and safety of parts used in pharmaceutical, bio-processing, and other industries requiring a hygienic vessel, called ASMP-BPE. BPE (Bio Processing Equipment Standard) specifies the surface finishes RA (roughness average) requirements and pickle passivation and electropolishing requirements.

Tests & Certification
There are significant testing, certifications, and documentation requirements for ASME compliance and satisfying the numerous customer requirements. Many require ASME inspection as well as a TOP (turnover packet).  Some 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 has been ASME certified for over 40 years. In addition to ASME, Apache is accredited in many other global standards. By setting parameters for quality and compliance, we offer greater value for our custom stainless ASME tanks and vessels.


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