Seamless Pipe

Lomond Engineering has a commitment to holding significant stocks of approved brand Seamless Pipes used in a variety of industries, where strength and quality are critical. Seamless Pipe is generally produced by piercing a solid billet of steel, and may be hot formed or cold drawn depending on the product size and specification guidelines. Some specifications, such as API 5L may cover both Seamless and Welded (ERW, EFW, LSAW etc) executions, whereas pipes specifically for high temperature steam and other processes may be seamless only (ie. ASTM A335).

Carbon Steel

Seamless carbon steel pipes have a variety of uses in process pipework (down-stream) and transmission (mid-stream) applications. The most used grades are ASTM/ASME A/SA106-B, A53-B and API 5L-B, which are available in seamless construction and stocked by Lomond Engineering in approved brands (non-Chinese/non-Indian). We specialise in heavy wall, hard to find schedules such as XXS, S160, S120, S140 etc.

Low Temperature Carbon Steel (LTCS)

Most piping codes allow the use of plain carbon steels at temperatures to -28°C, however where lower temperatures are involved (typically down to -50°C), impact tested carbon steels may be specified. Whilst the chemistry is generally not that different to plain carbon steels, the manufacturing process requires specific heat treatment to attain a fine grain practice and increase impact toughness. Low temp materials to A333/SA333 have minimum Charpy impact (CVN) testing requirements. We are also noticing a shift to low temperature materials by major Oil and Gas operators, in applications where plain carbon steels were previously used.

High Temperature (CrMo)

Generically named “P-Grade” piping, Chrome Moly ASTM/ASME A335/SA335 specification piping has increased properties over carbon steels at elevated temperatures, primarily through the inclusion of Chrome and Molybdenum (although other elements are added in some grades). The most common power generation and petrochemical process pipework grades are P11, P22 and P91 and more recently P92. In the refining sector, P5 and P9 materials are more commonly specified. Size and grade combinations, if not in stock, can be sourced from our worldwide network of vendors.

Stainless Steel

Seamless stainless steel pipes have a variety of uses in process pipework (down-stream) and transmission (mid-stream) applications. The most used Standard Stainless ASTM A312/A312M-22 and Duplex, Super Duplex ASTM 790-790m-14. Our stocked grades are Stainless TP316/L, TP304/L, and Duplex UNS S31803, UNS S32750 which are available in seamless construction at Lomond Engineering in approved brands (non-Chinese/non-Indian). ASTM A312 covers austenitic stainless steel pipes intended for high-temperature and general corrosive service. The standard ensures that pipes meet strict requirements for chemical composition, mechanical properties, and testing, making them suitable for demanding industrial applications such as chemical processing, oil and gas, and marine environments. ASTM A790/A790M specifies seamless ferritic/austenitic stainless steel pipes intended for general corrosive environments, particularly where resistance to stress corrosion cracking is critical.