MR-5000 Combustion

An essential part of the System 500

family of products.

MR-5000 Combustion Systems

Either supplied as a stand alone product or to accompany our System 500 technology, the MR-5000 forehearth & distributor combustion system is an essential part of our family of glass conditioning products.

Key Features

  • PSR multi-ratio air/gas mixer provides a constant air/gas ratio throughout the firing range.
  • High pressure firing system with a high turn down ratio provides better control response and reduced gas consumption.
  • PSR designed mixer air valve provides linear flow output.
  • Optional side to side combustion control optimises glass thermal homogeneity.
  • Supplied as a complete combustion skid reducing on site installation and assembly.
  • Ceramic burner nozzles reduce maintenance and maintain combustion efficiency.


The MR-5000 combustion system is a pre-assembled skid-mounted combustion system built around the Maxon Multi-Ratio Mixer. This incorporates a combustion air port valve, gas valve, adjustable gradient air/fuel control cam assembly and venturi mixing tube in one compact unit for precise air/fuel ratio control throughout the burner firing range.

The mixer body houses an air port valve and a gas valve. A rotating quadrant connected to the top of the mixer body carries a cam assembly with adjusting screws and the air sleeve of the port valve which sits inside the mixer body.

The adjustment screws determine the position of a plunger in the gas inlet which controls the flow of gas entering the mixer. These screws can each be set to give a precise air/gas ratio at that position. Setting the adjustment screw positions throughout the rotation of the mixer body provides a constant air/gas ratio throughout the firing range.

Additionally, the profile of the cut out in the modified PSR air sleeve is designed to provide a linear increase in combustion air flow through the mixer as the screw carrier is turned through 90° from the minimum to the maximum position ensuring close control of the combustion conditions and temperature within the forehearth. This complements the System 5oo roof block configuration where the side combustion chambers are separated from the central cooling chamber by allowing the firing rate on each side of the forehearth to be adjusted independently. Used with PSR’s advanced control strategies this enables continuous control of the side to centre temperatures and optimises the glass thermal homogeneity as measured by the 9 point thermocouple grid at the entrance of the spout.

As with all PSR equipment the MR-5000 combustion skid is designed to conform with the necessary standards such as EN-746 Part 2 (2010), NFPA 86 (2007) or any other appropriate local standards as required and as advised by the customer.

Ceramic Burner Nozzles

A common problem on most glass forehearths and distributors is that of the blocked burner nozzles causing combustion and control deficiencies. This is due to the volatile materials within the forehearth atmosphere and the steel burner nozzles providing a relative cold surface on which these materials can condensate and build up.

Ceramic burner nozzles operate at a higher temperature due to their lower thermal conductivity, reducing or eliminating the build up of condensates on the nozzle tip. This eliminates the maintenance requirements associated with cleaning the nozzles and maintains the efficiency of the combustion.

The PSR ceramic burner nozzle is made from a complete 95% alumina piece and is designed to replicate the function of a steel nozzle eliminating any additional problems which can occur from improper sealing of the burner nozzle against the inside and outside face of the burner block. These nozzles are now supplied as standard with every MR-5000 combustion system or can be retrospectively installed on existing PSR and competitor forehearth systems.

TOP: Forehearth burner with conventional stainless steel nozzle.
BOTTOM: Forehearth burner with PSR's ceramic burner nozzle.