Guichon manufactures valves specially adapted to the production of PBT :

Multiways valve, Injection valve, Tank bottom valve

Three-way lift plug valve
Type : 321

DN 1/2" to 6" Class 150 to 2500 Lbs
– Fully jacketed
– Lift plug for friction free rotation
– Stainless steel or special alloys
Three-way piston valve
DN 4" x 4" x 4" Class 2500 Lbs
– Stainless steel body and heating jacket
– Electric actuators (on-off and control service)
– 316L stainless steel

Three-way piston valve
DN 3"x 2" Class 600 Lbs
– Additional side mounted sampling or injection valves
– Manual gear operators


  • Construction materials: Carbon Steel (CS), Stainless Steel (SS), Duplex & Super Duplex, Titanium, Zirconium, Uranus® B6, Tantalum, Nickel, Hastelloy®, Monel
  • Construction methods: Fabricated (Welded), Cast, Solid


  • Service conditions: High pressure, High temperature, Low temperature, Abrasion, Corrosion, High viscosity, Vacuum, Reliability, Low acoustic signature, Dead space free
  • Types of fluids: Liquids, Liquids with solid particles, Gas, Powder and powdery media, High viscosity fluids


PBT – Uses of PBT :

– Insulating material for high temperature and high stress
– Boxes contactors
– Switches
– Household appliances
– Gear

Posted in: FAQ - PBT

PBT – Manufacturing process of PBT :

PBT (polybuthylene terephthalate) emerged on the market towards the sixties as a raw material for synthetic fibers and engineering plastics. It belongs to the group of linear, saturated polyesters. PBT faces inter-material competition from other thermoplastics with similar properties such as polyacetal, nylon or other terephthalic polymers (PET, PTT).

The main raw materials used to manufacture PBT are 1,4-butanediol (BDO), dimethyl terephthalate (DMT), purified terephthalic acid (PTA) and catalysts. Hitachi, Uhde Inventa-Fischer, and Lurgi Zimmer AG are the main licensors of PBT technology and cover the full spectrum of process variations (DMT vs PTA route,batch vs continuous).

There are different design variations that go from a 5-Reactor (5-R) to a compact 2-Reactor (2-R) configuration. Recent technologies (Zimmer COMBI reactor, Uhde Inventa-Fischer ESPREE and DISCAGE reactors) propose a 2-R design by combining the esterification and pre-polycondensation into one reactor, thus reducing the overall investment. As an example, the Zimmer 2-R process is illustrated in the figure 1 below.

Example of PBT manufacturing process

Figure 1. Zimmer continuous PBT process (PTA route). During the reaction, THF and water are also produced under elevated temperature and reduced pressure

Posted in: FAQ - PBT

PBT – Recommended valves :

Each step of the production process of PBT has undergone many improvements over the years. Design development, research of catalysts and optimization of special valves for PBT continues today.

Posted in: FAQ - PBT