What Are the Items on the PWHT Equipment List?

The PWHT Equipment List is an essential document that serves to assist Project Contractors when purchasing equipment for their projects. It works hand in hand with other specifications such as Supplementary Requirements Specification, Quality Requirement Specification and Equipment Data Sheets to make informed purchasing decisions.

This far infrared heating equipment can be used for pre-weld heat treatment, post weld heat treatment, stress relief and annealing processes.

Heater

Heaters are devices designed to raise the temperature of something. This could mean heating an entire room, or simply being portable enough for personal use. They’re an integral component of cars and it’s common to see one installed within every car on the road today.

Important for successful PWHT equipment installation is being able to achieve and maintain uniform heating around welds and HAZs. This can be accomplished with either a permanent fixed furnace, or for more difficult components a temporary furnace erected on site (ie a bogie loaded furnace with wheeled furnace bed or top hat furnace).

PWHT operations must also ensure the component can be supported appropriately to avoid excessive distortion; to achieve this goal, custom shaped trestles with regular spacing may be needed to support it during its process.

Thermocouple

The thermocouple is an invaluable safety device, used to monitor and shut off gas supply when your furnace pilot light goes out. Composed of two insulated wires made from various metals, its voltage output allows users to read pilot light temperatures as well as keeping gas lines open.

Thermocouples are designed to withstand high temperatures and can be used in a range of applications. When selecting the appropriate thermocouple type for an application and environment, it’s essential that they take your needs and expectations into consideration before selecting one. Assess the desired maximum and minimum temperatures as well as any chemical resistance requirements before considering lifespan expectations and any possible exposure to vibration or bending stresses.

Thermocouples operate under the principle that two dissimilar metals will produce an electromotive force (EMF) at their measuring junctions, an effect known as Seebeck Effect. Since its voltage output is usually low, an amplifier circuit must be employed to amplify it before using a reference table to translate this voltage reading into temperature readings using reference tables that list temperatures at which each thermocouple produces specific voltage readings; common types include nickel-chromium and nickel-alumel varieties but others exist that feature unique conductor combinations identifying each type using letters such as K, T or J to indicate which type they fall into.

Ni-Cr Wire

Nickel-chromium alloys have long been an attractive solution, thanks to their resistance to corrosion, oxidation and melting as well as their high electrical resistivity, making it an excellent choice for resistor elements. Our standard 26 gauge and 28 gauge Nichrome wire is easily bent; both gauges can heat up quickly when an electric current is applied – however thinner gauges require greater current to reach red hot temperatures than these medium gauges.

80/20 Nichrome wire is an immensely popular type of resistance heater wire, composed of 80% nickel and 20% chromium. Able to withstand temperatures up to 1200oC while providing excellent oxidation resistance, this material makes an excellent choice for domestic appliances as well as metal-film resistors.

Nichrome wire is an essential element of PWHT, as its proper functioning ensures correct operation of resistor elements. Therefore, equipment should be free from any lubricants, dust or coatings as these will lead to short circuiting. PWHT exposes components to high temperatures over extended periods, potentially damaging them if exposed for too long; to protect these components during PWHT by using deoxidizers like molten silica deoxidizers may be beneficial.

Recorder

As part of post weld heat treatment (PWHT), components must be constantly monitored in order to prevent damage, so a recorder is essential in this process. A recorder provides accurate and up-to-date data throughout PWHT operation that allows engineers to assess when PWHT should end, as well as making adjustments if temperature falls outside its specified range.

Recorders can be an invaluable tool in quickly and accurately diagnosing systemic issues, helping reduce downtime due to equipment failure. Cooperheat’s temperature chart recorders are widely recognized for their accurate recording capabilities that can prevent costly rework during PWHT processes.

The Posatavk Prkssurk Watnag Btk (PWHT Recorder) is an advanced PWHT recorder that offers excellent temperature stability and resolution, meeting the highest quality standards while offering numerous useful features that enhance efficiency. Furthermore, this device features a forced natural air cooling fan to improve cooling effect of machine and extend its working lifespan.