Trailers of All
MC 331, 338, 406, 407, 412 CARGO TRAILERS
LPG, NH3, CO2, Chlorine and
cryogenic transports; complete design and stress analysis.
HLA is a Design
Certifying Engineer for the DOT (Registration Number CT-0012), with
over 21 years of experience in the design and analysis of DOT MC
equipment: cargo transport trailers of all types and DOT 51 containers
- both portable and intermodal. HLA has designed LPG & Anhydrous
Ammonia Cargo Trailers (10,500 - 17,000 W.G.), Chlorine, CO2, SO2 and
Cryogenic Transport Trailers.
HLA completed a
contract for the DOT in January of 1985, to determine the stresses in
the head to shell joint of typical MC331 vessels. This stress study
centered on the Rub Plate Box area of the typical MC331 cargo
transport. The resulting surface stresses were compared to present DOT
code allowables, demonstrating the need for revised MC331 structural
integrity guidelines. Plumbing guards, bumper and design acceleration
inconsistencies were also pointed out in the report.
HLA played a
significant role in the redefinition of the over-the-road design
acceleration requirements for MC331 vehicles. In communication with
the DOT, HLA pointed out the need to correct the "Principal Stress
Equation", then called "DOT Effective Stress", and was largely
responsible for the correction in CFR49.
HLA has worked on
many difficult topics in the MC 306, 307 & 312 areas: non-linear
(plastic) bumper analysis, non-linear roll-over guard analysis with
resulting shell stresses, as well as stiffener ring and baffle
location and geometry to coordinate with roll-over protection.
HLA has over 21
years of experience on the design and analysis of ASME Pressure
Vessels, Divisions 1 and 2, API 620 and 650: horizontal, vertical and
spherical, including saddles, skirts, columns and other support
systems. HLA has designed and analyzed numerous pressure vessels to
ASME Pressure Vessel Code, Section VIII, Division 1 requirements.
Several subcontracts for NASA projects involved the design and
analysis of cryogenic vessels for use in the rocket program. These
vessels were designed and analyzed to ASME Pressure Vessel Code,
Division 2, with the resulting analysis submitted to NASA for review.
This analysis also utilizes the finite element analytical technique
for not only the pressure and dead loading, but for seismic and wind
HLA performed an
extensive damage tolerance study of dry cargo containers for the
Institute of International Container Lessors (IICL), which was over
five years in length. A survey was made of various types of
construction of existing dry cargo containers, and a series of
physical tests in combination with finite element computer modeling
was used to determine the types of damage, extent and location of
damage these containers can tolerate without being repaired.
HLA has designed,
tested and received ABS approval for more than 11 different designs of
intermodal dry cargo and tank containers, including military
containers with end and side doors, and refers.
National Propane Gas Association
transportation project was performed by HLA for the National Propane
Gas Association. HLA Engineers had a contract to perform a study of
the Department of Transportation (DOT) regulations governing the
design of MC331 transport trailers - making recommendations of design
accelerations and stress criteria changes to the regulations, based on
stress analyses of existing equipment designs, details and practices.
The end result is intended to be a concise guide for the design
engineer, and will hopefully assist him in making consistent, safer
decisions for the design of this type of transportation equipment.
HLA has also
performed design and analysis of ASME pressure vessels (Section VIII,
Divisions 1 and 2), cryogenic pressure vessels, ISO intermodal tank
and dry cargo containers, MC 331 transports and many other types of