[Federal Register: September 30, 2009 (Volume 74, Number 188)]
[Notices]
[Page 50272-50273]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30se09-118]
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DEPARTMENT OF TRANSPORTATION
Pipeline and Hazardous Materials Safety Administration
[Docket No. PHMSA-2009-0158]
Pipeline Safety: Weldable Compression Coupling Installation
AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA);
DOT.
ACTION: Notice; Issuance of Advisory Bulletin.
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SUMMARY: The Pipeline and Hazardous Materials Safety Administration
(PHMSA) reminds pipeline owners and operators of the importance of
installing weldable compression couplings in accordance with
manufacturer procedures and following appropriate safety and start-up
procedures. The failure to install weldable compression couplings
correctly, or the failure to implement and follow appropriate safety
and start-up procedures, could result in a catastrophic pipeline
failure. PHMSA strongly urges operators to review, and incorporate
where appropriate into operators' written procedures, the
manufacturer's installation procedures and take any other necessary
safety measures for safe and reliable operation of pipeline systems.
FOR FURTHER INFORMATION CONTACT: Ivan Huntoon by phone at (816) 329-
3829 or by e-mail at ivan.huntoon@dot.gov.
SUPPLEMENTARY INFORMATION:
I. Background
In 2007, a crude oil release occurred during maintenance activities
on a major oil pipeline. The escaping crude oil ignited and resulting
in two fatalities. When this incident occurred the operator was
performing a pipe replacement using pre-tested pipe and weldable
compression couplings. The failure occurred during start-up operations
when the forces associated with pipeline operations exceeded the
restraining capability of the unfinished replacement assembly. As
pressure increased, movement of the piping occurred resulting in the
eventual separation of the pipe from the weldable compression coupling.
There was sufficient mechanical breakdown and the escaping crude oil
created a flammable vapor-air mixture which ignited a few seconds after
the release began. The pipeline was being re-started to allow for
welding of the compression couplings to the pipe when the release
occurred. The failure occurred while pressure and flow were increasing.
The weldable compression couplings use radial bolts (clamp screws)
to attach the compression coupling to the surface of the pipeline. Once
attached, longitudinal bolts apply pressure to a steel ring and
neoprene seal which expands, providing a compressive seal between the
weldable compression coupling and exterior surface of the pipe. The
compression couplings are designed to be fillet welded to the pipe
surface after bolting and sealing, making them a permanent welded
repair.
In the above referenced incident, the weldable compression
couplings had been modified prior to the installation by cutting off
approximately half of the clamping bolts which reduced the restraining
capability of the replacement assembly. The manufacturer's installation
procedures did not authorize this modification. In addition, operators'
procedures specific to the installation of compression couplings must
provide sufficient guidance for their employees to determine whether a
pipeline is fully anchored prior to welding. In the above referenced
incident, the manufacturer's literature described a pipeline in the
anchored condition as being ``restricted from movement in all
directions'' and the operating pressure chosen by the operator to be
sustained for welding was based on the manufacturer's recommendation
for a fully anchored installation. However, the physical
[[Page 50273]]
characteristics of the installation indicated that it was not fully
anchored and that it needed to be limited to a much lower maximum safe
working pressure. Operator personnel must be specifically trained and
qualified for the installation of weldable compression couplings
including ensuring that the extent to which the pipeline is not fully
anchored is taken into account when determining the maximum safe
working pressure.
To ensure safety, pipeline operators using weldable compression
couplings must ensure personnel are trained and qualified to perform
the installation. Also, operators must ensure their procedures
accurately incorporate manufacturers' procedures and limitations on the
use of weldable compression couplings and ensure that the procedures
are available, understood and followed by personnel. PHMSA believes
that the risk of compromising safety posed by unauthorized
modifications to weldable compression couplings is unacceptable. PHMSA
strongly recommends that any field changes in the installation process
(i.e., modifications allowed by a component manufacturer) that could
affect component performance and safety be subject to a documented
authorization process, communicated to appropriate personnel, and be
reflected by allowable working pressures. Allowable working pressures
vary greatly between anchored and un-anchored installations. In order
to use the pressure rating for an anchored installation, the operator
must verify the pipeline is anchored in all directions in accordance
with company and manufacturer procedures prior to pipeline start-up. To
ensure safety for personnel, property and the environment, pipeline
start-up procedures must be available and followed. Finally, any
failure to identify and restrict access to hazard zones during
pressurization of exposed pipeline sections could compromise safety.
II. Advisory Bulletin ADB-09-02
To: Owners and Operators of Hazardous Liquid and Natural Gas
Pipelines.
Subject: Weldable Compression Couplings.
Advisory: The Pipeline and Hazardous Materials Safety
Administration (PHMSA) advises operators of hazardous liquid and
natural gas pipelines installing or planning to install weldable
compression couplings and similar repair devices to follow manufacturer
procedures to ensure correct installation. In addition, PHMSA also
advises these operators to follow the appropriate safety and start-up
procedures to ensure the safety of personnel and property and protect
the environment. The failure to install a weldable compression coupling
correctly, or the failure to implement and follow appropriate safety
and start-up procedures, could result in a catastrophic pipeline
failure. PHMSA strongly urges operators to review, and incorporate
where appropriate into operators' written procedures, the
manufacturer's installation procedures and any other necessary safety
measures for safe and reliable operation of pipeline systems.
Issued in Washington, DC September 23, 2009.
Jeffrey D. Wiese,
Associate Administrator for Pipeline Safety.
[FR Doc. E9-23527 Filed 9-29-09; 8:45 am]
BILLING CODE 4910-60-P