In May 2009, Roc-Master successfully got a duplex piping products order for CNOOC (China) limited (Zhanjiang) Yacheng PFA project (It was the Yacheng wellhead manifold reforming and pipeline tied-back engineering). The products in this order included ASTM A815 UNS S31803 API 5000PSI BW & Forged pipe fittings, ASTM A182 F51 2500LB flanges and their ancillary fasteners of ASTM A453 GR660 with XYLAN 1424 green coating.
 It is the first time for the end user, BP, adopting such duplex piping products in large quantities in China. Before the ordering, BP and CNOOC (China) limited Zhanjiang Yacheng PFA project sent their expert group and engineers come to Roc-Master to have a detailed discussion on the duplex piping products processing and meanwhile went through a strict supplier survey on Roc-Master's quality system.
On the basis of good prices advantages and on the basis of the engineers’ onsite witness to the whole fabrication course, We cost half of the time delivering 100% qualified products, compared with other supplier overseas.
With the guidance of our senior heat treatment engineer, we did several times of heat treatment tests, finally we passed the authentication body’s detection once and for all , and the ferrite content was between 45%~55% that fully complied with the severe requirements in the technical specifications. ( normally the ferrite content should be between 40%~60% in standard).
According to the specification of the end-user, such high pressure duplex BW pipe fittings of ASTM A815 UNS S31803 need a burst test on their engineer’s whole course witness. The calculating burst pressure was 144.9Mpa, the final testing pressure should be 1.05 times of the calculating pressure,( namely 152.1Mpa), as long as no burst under 152.1Mpa, the products are qualify. Actually the final bursting test pressure was up to 171.1Mpa.The test was held in pressure vessel inspection station of Hefei General Machinery Research Institute.
The test result proved that Roc-Master is in the leading place with regards to the fabrication processing & heat treatment processing in China, the perfect delivery obtained the acknowledgement and the praise from BP company. What’s more, Roc-Master repeatedly completed duplex piping products orders of CNOOC, Sinopec, ConocoPhillips and Modec.


Bursting test of the Duplex BW pipe fittings 
双相钢关键出货前
Duplex Stainless steel Sand Tees before shipment

Duplex Stainless Steel Flange after inspection

A453 GR660 Fluorocote Stud Bolts with Green coating In Inspection

Duplex Stainless Steel BW fittings In Inspection.