Pipe Cutting & Weld Prep Machines

Pipe Cutting & Weld Prep Machines

Product Description

Pipe cutting and weld prep machines, also known as split frame clamshells, cut and bevel pipe in place without heat, flame or sparks. They clamp around the pipe, rotate a cutting tool around it and machine a square cut and a weld ready bevel in the same pass. BLJ In-situ Solutions holds a hire fleet covering 4 inch to 60 inch diameter pipe.

Because the cut is mechanical rather than thermal, there is no heat affected zone. The pipe is not distorted, the material properties either side of the cut are unchanged, and the work can be carried out in atmospheres where an open flame would not be permitted. That is why cold cutting is standard practice on live plant, in hazardous areas and on any line where the weld has to pass inspection first time.

How Split Frame Clamshell Machines Work

The frame is split, so it opens and closes around pipe that is already installed. There is no need to break the line apart to get the machine on. Once clamped, the tool bits feed automatically into the work piece with each rotation of the clamshell, which produces a consistent and precise finish rather than one that depends on operator feel.

These are portable pipe lathes. They simultaneously sever and bevel inline pipe, and they can form an angle bevel as they cut, so a single set up delivers a cut face that is ready for weld preparation. A swivel counter boring head attachment is also available for hire where the internal diameter needs to be machined to suit the weld procedure.

Pipe Cutting and Weld Prep Machine Hire

Pipe diameter range: 4 inch to 60 inch (approximately 100mm to 1,525mm)
Drive: air driven, suitable for hazardous area work where electrical tools are restricted
Machine type: split frame clamshell, mounts on in-line pipe without dismantling the run
Operations: severing, bevelling, simultaneous sever and bevel, counter boring with the optional swivel head
Supplied with: the tooling and equipment required to set up and operate

The range covers small bore pipework right through to large diameter vessels, so a single supplier can handle a mixed scope across a plant.

What These Machines Are Used For

Cutting out and replacing a section of corroded, eroded or damaged pipe
Preparing weld ends on new pipework tie-ins during construction and plant modification
Cold cutting on live or recently isolated lines where hot work permits are difficult or refused
Cutting in hazardous and classified areas where flame cutting is not an option
Removing valves, spools and fittings without disturbing the surrounding pipework
Decommissioning and cutting up redundant plant and pipework
Machining weld preparations to a specified angle and root face during a shutdown

Pipe cutting is often one element of a larger scope. It runs alongside our on-site machining services and is frequently mobilised as part of a shutdown or turnaround, where a tie-in has to be cut, prepped, welded and returned to service inside a fixed window. Where the same outage also involves flange work, our flange joint management and controlled bolting teams work the scope together.

Hire the Machine, or Hire the Machine and the Technician

You can hire a pipe cutting and weld prep machine and run it with your own crew, or we can supply the machine with a BLJ technician who carries out the cut. Clients often take the second option when the bevel has to meet a specific weld procedure, or when the line is live and the job carries no margin for a second attempt.

What you need to provide: the air supply, safe access around the full circumference of the pipe, and confirmation that the line is isolated, drained and safe to cut. Clearance around the pipe matters more than people expect, because the clamshell rotates around the outside of it. Our team will check this with you before delivery.

Machines are dispatched from our workshops in Brisbane and Gladstone, Queensland, and we mobilise to sites across Australia including Brisbane and Lytton, Gladstone, Karratha, Perth, Newcastle and the Hunter Valley and Sydney. The rest of the fleet is on our on-site machining equipment hire page.

Pipe Cutting and Weld Prep FAQs

What is cold cutting?

Cold cutting is cutting metal without heat, flame or sparks. Instead of burning through the material, a mechanical cutting tool removes it. This avoids a heat affected zone, so the material either side of the cut keeps its original properties and the pipe does not distort. It also removes the ignition risk, which is what makes it suitable for work on live plant and in hazardous areas.

What is a split frame clamshell machine?

A split frame clamshell is a portable pipe lathe whose frame splits in two so it can be fitted around pipe that is already installed. Once closed and clamped, the frame rotates around the pipe carrying the cutting tools with it. It is the standard machine for cutting and bevelling in-line pipe without dismantling the run.

What is the correct bevel angle for a pipe?

For a standard single V butt weld preparation the included angle is commonly 37.5 degrees, though the correct figure for any given job comes from the applicable weld procedure specification rather than a general rule. Wall thickness, material and the welding process all affect the preparation required. Our machines cut to the angle and root face your procedure calls for.

What size pipe can BLJ cut on site?

Our fleet covers 4 inch to 60 inch diameter pipe, which is approximately 100mm to 1,525mm. That range takes in most process pipework as well as large diameter vessel and header work.

Why cut pipe in-situ rather than removing it?

Removing a section of pipe to cut it elsewhere means disassembly, transport, machining, return transport and reassembly, and every one of those steps carries time, cost and the risk of introducing a new problem. Cutting in place removes all of it. We bring the workshop to you and work in-situ, saving time and money.

Can pipe cutting be done during a shutdown?

Yes, and that is where most of this work happens. Cold cutting suits a shutdown because it needs no hot work permit, produces no sparks near other trades and delivers a weld ready face straight off the machine, which keeps the welding crew moving. BLJ In-situ Solutions mobilises pipe cutting alongside our other on-site machining disciplines as part of a single shutdown scope.

Where does BLJ provide pipe cutting and weld prep services?

BLJ In-situ Solutions operates from workshops in Brisbane and Gladstone, Queensland, and mobilises to sites across Australia, including remote and regional locations. We work for clients in energy, LNG, oil and gas, utilities, petrochemical, mining, construction and infrastructure.

Download Data Sheets

Enquire Today