A/R (Area/Radius) is a term used to define a geometric characteristic of all turbine and compressor housings.
Cast iron housing, the centre of the turbo that houses the turbine piston ring seal, the journal bearing(s) and the thrust bearing, which are all fed with pressurised oil from the engine.
Indicates the flow limit and is located on the right side of a compressor map.
CHRA/ Core Assemblies
(Centre Housing Rotating Assembly) The CHRA is essentially a turbocharger minus the compressor and turbine housings. It incorporates the complete rotating assembly, shaft & wheel, bearing housing and compressor wheel.
Radial multi-bladed compressor in a turbocharger that draws in ambient filtered air, compresses it within housing, and then blows it out into the intake of the engine.
Corrected Air Flow
In order to plot the airflow data on a compressor map, you must ensure the flow is corrected to account for differences that affect air density, such as atmospheric conditions.
This is a turbo without a Wastegate. Therefore the turbo is unable to regulate its own boost levels.
Thin plate that protects & separates the top of the bearing housing from the high temperatures of the exhaust gases. It is positioned between the bearing housing and the revolving turbine wheel.
Fits inside the bore of the bearing housing and prevents radial movement of the shaft & wheel.
On-Centre Turbine Housings
On-centre turbine housings is an old design turbine housing with a centred turbine inlet pad.
Non-moving seal which prevents oil or air getting between different components.
Is a term used when a turbo is operating well above its normal operating limits.
Type of seal commonly used in turbochargers to prevent air, gas or oil getting where it shouldn’t. A pressure differential seal.
Absolute outlet pressure divided by absolute inlet pressure. For Example: (Boost + DPIntercooler+ Atmos) / (Atmos-DPAir Filter) = Pressure Ratio
Minor – includes just the basic components;
Major – includes all the components needed for a full repair of a turbo; Universal Kits – includes each variation to accommodate for where there are several variations of a model i.e. Flat or superback compressors wheels, straight or slender shafts etc.
The component, usually made from aluminium, has a bore housing the compressor end piston ring seal that runs in the groove of the oil flinger or thrust collar. On some models, this component doubles up as being the supporting flange that the compressor housing fixes to.
Shaft & Wheels
The complete assembly that describes the turbine wheel and shaft as one component – (Also referred to as a ‘Turbine Wheel’). It uses the exhaust flow from the engine to spin a turbine, which in turn spins an air pump.
Holds the compressor wheel and other rotor group parts onto the shaft. This normally has a left hand thread on modern turbos, this high precision machined nut has to be tightened to a specific torque.
A single flat bearing that supports the positive and negative axial loads generated when the turbo rotor accelerates and decelerates. The bearing is fixed and the thrust collar runs within it. A pressurised oil film separates the ramped faces of the bearing from the journal surfaces of the collar.
The half of a complete thrust collar that runs on the underside of the thrust bearing. The thrust collar is sometimes in two pieces for applications like a 360 degree thrust bearing.
Located on the turbine shaft, this sits through the hole in the seal plate and acts as a separator/seal between the thrust bearing, seal plate and compressor wheel.
Fits between the journal bearing and thrust bearing, acting as a cushion to prevent the parts form touching.
Is the area ratio used to define the turbine and compressor wheels. To calculate the trim you use the inducer and exducer diameters. For Example: Inducer2/Exducer2 = Trim
Melett UK will close for the Jubilee bank holiday at 17:00 on Wednesday 01 June and reopen at 08:00 on Monday 06 June. Any orders that are not picked or dispatched before we close will resume preparation when we reopen. If you would like any more information or guidance on the above, please contact our customer care team on +44 (0)1226 320939.
Memorial Day 2022
Melett North America will be closed for Memorial Day on Monday May 30th and will reopen at 8.00 am on Tuesday May 31st.
Melett Polska will be closed for a public holiday on Thursday 16th June and will reopen on Friday 17th June. Any orders that are not picked or dispatched before we close will resume preparation when we reopen. If you would like any more information or guidance on the above, please contact our customer care team on +44 (0)1226 320939.
May Bank Holiday opening hours
Will close 5.00 pm Friday 29th April and reopen 8.00 am Tuesday 3rd May
Will close 4.30 pm Friday 29th April and reopen 8.00 am Wednesday 4th May
PLEASE NOTE -THE ABILITY TO SUBMIT YOUR ORDERS THROUGH THE MELETT WEBSITE HAS BEEN RESTORED
We are delighted to advise full website functionality has now been restored, meaning you can view stock and pricing, add parts to your basket and submit your order via the website. In addition, all turbo/part number searches are fully working.
Until further notice please place your orders by 2.30 pm and we will endeavour to dispatch the same day dispatch.
We will keep you updated as we navigate through the remaining internal connectivity issues, we have dedicated teams working round the clock to resolve any remaining issues as quickly as possible.
We, at Melett, would like to stress our gratitude for your continued patience and support throughout this difficult time.
Please note you can now view your pricing on the Melett website.
We appreciate this is not a complete solution at this stage, however, please be assured our internal website and IT teams remain focused on reinstating the stock availability function.
We cannot stress enough that we are doing everything we can to reconnect our internal system, and we will restore full website functionality as soon as possible.
If you experience any problems whilst ordering online, please do not hesitate to contact:
W związku z awarią sieci telefonicznej prosimy o kontakt na telefon komórkowy: Damian 512 372 612; Kasia 511 372 612
Melett UK will be closed on Monday 29th August and will reopen at 8.00am on Tuesday 30th August.
Any orders that are not picked or dispatched before we close on Friday 26th August will resume preparation when we reopen. If you would like any more information or guidance on the above, please contact our customer care team on +44 (0)1226 320939.
Melett Polska will be closed for a public holiday on Friday 11th November and will reopen on Monday 14th November.
Any orders that are not picked or dispatched before we close on Thursday 10th November will resume preparation when we reopen. If you would like any more information or guidance on the above, please contact our customer care team on +44 (0)1226 320939.
Queen Elizabeth II state funeral - Monday 19th September
Melett UK will be closed on Monday 19th September for the state funeral of Queen Elizabeth II . Melett will be joining people and businesses across the country in reflecting on Her Majesty's incredible contribution and enduring legacy.
Melett North America and Melett Polska will remain open as normal.
Easter opening hours
Melett UK - will close 17:00 Thursday 14 April and reopen 08:00 Tuesday 19 April Melett Polska - will close 16:30 Thursday 14 April and reopen 08:00 Tuesday 19 April Due to essential maintenance, the Melett website will be temporarily unavailable on Thursday 14 April from 17:30 to 19:30. We apologise for any inconvenience caused.
Due to essential maintenance, the Melett website will be temporarily unavailable on Friday 25 February from 18:00 to 20:00 (GMT). We apologise for any inconvenience caused.
Planned maintenance – Thursday 24 March 2022
We will be undertaking planned maintenance on our internal systems this evening between 17:00 and 20:00 GMT, which will affect some website functionality.
We aim to keep disruption to a minimum and the website will remain online. However, we will need to temporarily disable online ordering during this time.
Thank you for your understanding.
We are undertaking essential maintenance this weekend (February 19-20) and some of our website services may be unavailable at times. We apologise for any inconvenience this may cause.
- Due to essential maintenance, the Melett website will be temporarily unavailable on Friday 28 January from 18:00 to 20:00 (CET). We apologise for any inconvenience caused.
Festive opening hours
- Melett UK Will close 5:00pm Thursday 23rd December and reopen 8:00am Tuesday 4th January
- Melett Polska Will close 4:30pm Thursday 23rd December and reopen 8:00am Monday 3rd January
- Melett North America Will close 5:00pm Thursday 23rd December and reopen 8:00am Monday 3rd January
Please note: Due to essential maintenance the Melett website will be temporarily unavailable on Friday 10 December from 5:00PM (CET) to 11:00PM (CET). Apologies for any inconvenience caused.
Please note; Unfortunately, we are experiencing processing delays for all orders which may result in delays in shipping. If possible, please confirm orders at your earliest opportunity to help minimise disruption to our normal high standards. Please accept our apologies and rest assured that we are working hard to resolve the issue.
Melett Poland will be closed for a Public Holiday on Thursday 11th November. Any orders that are not picked or despatched on Wednesday 10th November will resume preparation when we return on Friday 12th November.
Melett Poland will be closed for a Public Holiday on Thursday 6th November. Any orders that are not picked or despatched on Wednesday 5th November will resume preparation when we return on Friday 7th November.
Melett will be closed for a Public Holiday on Thursday 11th November. Any orders that are not picked or despatched on Wednesday 10th November will resume preparation when we return on Friday 12th November.
Melett will be closed from 5 pm on Wednesday 24th November until 8 am on Monday 29th November for the Thanksgiving holiday
Online ordering now available
In addition to viewing inventory levels and pricing, you can now place orders directly from our website. Download our user guide below to help you get started.