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Fasteners and gaskets are often the most overlooked of all the commodities associated within pipeline products and yet are responsible for holding/sealing everything together. As part of Alexander Comley’s wider offering we supply these items either as individual requirements but primarily as part of the one-stop-shop, package supply on offer. These can be offered to global standards and/or bespoke requirements.


The most common product required alongside flanges are studbolts, hex nuts and washers. Primarily, the materials are petrochemical grade and are supplied to specific needs as sought eg PED, NORSOK, NACE etc. The fastening components within the installed flange system provides the force to halt system leakage

Studbolt example material grades include: 304/H/L, 316/L/Ti, 321/H, 347/H, B7/M, L7/M, B8/M/T/C Cl. 1 & 2, 660 A/B/D, 31803, 32760/SA/FG/FLT

Hex Nut example material grades include: Gr.8/M/A/MA/T/C, 2H/M, Gr.4, Gr.7, 660 A/B/D, 31803, 32760

Thread form can be offered to suit eg UNC, UN8, UNF, BSF, BSW, metric

Additional process’s such as coating can be undertaken. Examples include: PTFE (Teflon, Xylar 1, Xylan 1070/1024), Zinc, Hot Dipped Galvanizing

Because of Alexander Comley’s reputation as a non standard manufacturing company it is common place for flanges to be in exotic non standard materials. The fastening requirements are a part of this

Other material grade examples include: Alloy 20, 200, 400, K500, Inconel 600/625/718/800/925, 31803 (Duplex), 32760 / 32750 (Super Duplex), Aluminium bronze

Should it be additionally sought further testing etc can be performed



Sealing technology is another critical but commonly overlooked part of a given pipeline system. This product comes in variety of guises from the more standard Ring Type Joint (“RTJ”) and Spiral Wound Gasket to the specially machined product. The force applied by the tightened fasteners in the installed flange system not only hold the gasket(s) in place but as long as tensioned correctly allow the gasket to perform within its optimum performance parameters.

Gaskets look to perform in an extreme range of environments from high temperature to high pressure and as such can come in a wide range of shapes, materials and have special requirements dependent upon final application.

RTJ standard style gaskets can be offered in accordance with standards such as API and B16.20. Commonly they come two main forms, octagonal and oval. RTJ’s applications go hand in hand with specially grooved flanges. Other forms on offer are “BX”, “RX”, “SRX” and “SBX”

Spiral Wound Gaskets are composed of a variety of soft metallic filler materials, metal wire and an outer guidance ring. They soft filler and metal wire are “wound” with these alternate materials and come is range of types.

As a lot of Alexander Comley finished, flanged product goes into critical, often hazardous petrochemical environments other sealing technology options are also on offer, namely Insulation sets, commonly Type “D”, “E” and “F”