Bellows Assets Recently Acquired by U.S. Bellows, Inc.
Located in Houston, Texas, U.S.A.

Phone: (281) 241-9418  Toll Free: (855) 591-0906  Fax: (661) 587-2022  E-mail:

Contact Us
Metal Expansion Joints
Fabric Expansion Joints
Pressure Vessels
Custom Fabrication;
Pipe Spool Fabrication
Process Skids
On-Site Service
U.S. Bellows, Inc.
Visit U.S. Bellows' Site

Piping and Ducting

 has the capability to design and manufacture round or rectangular ducting systems including metal or fabric expansion joints, guides and supports. Lortz engineers are knowledgeable in calculating the thermal, pressure, wind, seismic and physical loading imposed on ducting systems.

Ducting Design & Manufacturing Capabilities


  • ASME B31.3 and B31.1; AISC and Structural Building Codes


  • Wall Thickness: Round 2.5” Carbon, 2” Alloy; Rectangular 1/8” and thicker
  • Size: Finished duct sections 20 ft. x 20 ft. x 100 ft. long.
  • Weight limit per duct section approximately 100,000 lbs.
  • Duct Lining: All weldable ferrous and non-ferrous materials.
  • Welding: latest processes under the direction of our Chief Welding Engineer.

Lortz has more than 30 years experience with oversized and heavy truck transportation. We utilize our on fleet of trucks and specialty trailers and when necessary utilize the services of other specialty carriers. Our knowledge allows us to provide timely assistance to our customers for total freight coordination beginning in the proposal stage.

The Lortz Engineering Team is 21 Associates strong, 3 MSME, 6 BSME, 5 experienced Project Managers, and 8 SolidWorks Detailers.

Lortz specializes in Ducting System design and analysis and fabrication.

DESIGNXXINTEGRATION is a primary goal in Lortz evaluation of customer drawings. Integration involves analysis of ducting runs to eliminate as many “field” welds as possible and ship the largest logical duct section possible. Additionally, in that Lortz designs and manufactures metal and fabric expansion joints, Lortz will integrate metal and/or fabric expansion joints with the ducting thus eliminating field handling and installation of sensitive components.

Each Ducting order is assigned to a Lortz Project Manager that is involved from day one. The Project Manager is responsible for the entire order scope from receipt through shipment. MS Project Schedules are created and managed for each project.

When required Lortz Engineering will provide PE certified drawings and calculations.

Engineering software used by Lortz includes:

  • Codeware Compress and Coster
  • Coade Code Calc ASME Appendix 26 Metal Expansion Joint Analysis
  • Coade Caesar II Piping Analysis
  • Cosmos Finite Element Analysis
  • SolidWorks Design & Modeling
  • FLEXXCHECK Bellows Design Analysis SOLIDWORKS advantages

Solidworks Advantages

  • Collaboration with customers through the use of eDrawings and other integrated design communication tools to facilitate swift development of optimum end use application design solutions.
  • Import and export of more than 25 2D and 3D file formats directly to and from SolidWorks for almost unlimited customer interaction of designs.
  • Photorealistic renderings and animations for improved understanding of the final manufactured part.
  • Drawing interference detection during design to prevent drawing errors prior to manufacture.
  • Substantial reduction in rework and scrap during manufacturing operations.
  • Optimal use of raw materials through automatic “nesting” interface.

Quality Assurance and Operational Excellence are important foundations of Lortz’ 60 years of success in business.

Lortz has built a solid reputation with customers based on operational excellence and high quality products and service.

Lortz’ Quality Management System is in compliance with ISO 9001:2000 and ASME Section VIII and Lortz holds ASME “U”, “S”, “R”, “PP” and National Board “NB” certificates.

We have invested in state of the art inspection and NDE equipment that includes:

  • Dimensional Inspection -FARO “X” Laser Tracker CMM System
  • Positive Material Identification “PMI” -Nitton XL3T XRF Analyzer
  • Ultrasonic Inspection -GE Phasor XS
  • Video Imaging Boroscope -Olympus iPLEX FX
  • Digital Pressure Gages -Crystal XP2i
  • Hardness Tester -Equotip 3
    Lortz Manufacturing Company has implemented an advanced welding technology program that has been enthusiastically endorsed by all of the LortzWelding Team. The program emphasizes control of all welding processes to approved welding procedures assuring the highest quality, consistent welding results.

Lortz’ Quality Management System is in compliance with ISO 9001:2000 and ASME Section VIII Division 1 and Division 2, and Lortz holds ASME “U”, “S”, “R”, “PP” and National Board “NB” certificates. We have invested in state of the art inspection and NDE equipment that includes:

  • “One touch” weld parameter set up in compliance with qualified weld procedures.
  • Wireless transmitters monitored remotely for weld procedure compliance and overall Welder performance.
  • Automatic shut down of machines when weld procedure parameters are violated.
  • Remote programming of weld procedures into each welding machine
  • Multiple Process Capability – GTAW, GMAW, FCAW, SMAW.
  • Welding machine self-diagnostics for ease in trouble shooting and minimizing down time.

The Lortz Welding Team welders are qualified to ASME Section IX and AWS D1.1