Main materials used to make seals:
- metal parts – 1.4021; 1.4401, 1.4571, etc.;
- springs – 1.4571, 1.4401;
- friction pair rings – SiC, SiC+Si, SiC+Si+C, graphites with various impregnations.
Each seal is tested on a bench before being sent to the Customer. The company provides a guarantee for all supplied products, provides warranty and post-warranty service, supply of spare parts and devices for installation and dismantling of seals.
For use in the oil refining industry we offer the following brands of mechanical seals
- 11/62 STK – single;
- 52 STK – double “TANDEM” type;
- 53 STK – double.
For example, mechanical seals are presented in relation to pumps: NK, TKA, NPS.
The seals are designed to seal the shafts of pumps pumping oil, petroleum products, oils, organic solvents, water, aqueous condensate, aqueous solutions of acids, alkalis and other liquids (products) that do not have a corrosive effect on the seal parts. Main technical characteristics of seals:
- pressure (excess) of the product being compacted in the pump chamber before compaction, during rotation of the rotor, MPa (kgf/cm2) – from 0.035 to 3.5 (from 0.35 to 35);
- pressure (excess) of the compacted product in the pump chamber before compaction, without rotor rotation, no more than, MPa (kgf/cm2) – 4.5 (45);
- rotor speed, no more, rpm – 3600;
- temperature of the product being compacted in the pump, up to +260ºС;
- maximum axial movement, no more, mm – ±2.5;
- leakage of the compacted product (limit value), no more than l/hour – 0.02.
MECHANICAL SEALS GRADE 11/62STK
Single seal with product circulation through the seal body and an installed throttling sleeve on the atmospheric side.
Seals allow:
- in case of failure of the friction pair, prevent “fan” spraying of the product;
- organize control over the permissible volume of product leakage through the seal;
- organize flushing with steam or liquid of the internal cavity of the seal in which the springs are located.
Recommended piping schemes according to API 682 are schemes 11 and 62.
It is used in pumps pumping oil, diesel fuel, fuel oil, gasoline, formation water and oil.
MECHANICAL SEALS GRADE 52STK (“TANDEM”)
Double seal type
“TANDEM” in which, as a rule, the buffer liquid is located without pressure or pressure below the pressure of the product in the pump chamber before sealing.
Used when product leakage into the atmosphere is not permissible;
The circulation of the buffer fluid is ensured by a pump ring on the rotor seal sleeve.
The design of the seal allows the seal to operate even with a reverse pressure difference (the pressure of the product being sealed is lower than the pressure of the buffer liquid), a scheme with a line of double hydraulic load of the friction pair on the product side is used.
The recommended piping scheme according to API 682 is scheme 52 (scheme 53 is allowed).
MECHANICAL SEALS GRADE 53STK
A double seal in which the liquid is pressurized above the pressure of the product being sealed in the pump chamber before the seal.
Used when product leakage into the atmosphere is not allowed
The product is liquid or gas.
It is also intended for compacting products under vacuum.
The circulation of the barrier fluid is ensured by a pump ring on the rotor bushing.
The design of the seal allows operation with reverse pressure (the pressure of the products is higher than the pressure of the barrier liquid), a scheme with a line of double hydraulic load of the friction pair on the product side is used.
The recommended piping scheme according to API 683 is scheme 53.
All of the above seals have the following design solutions:
- “cartridge” design – the seals are assembled into a single unit and allow testing on a bench before installation on the pump;
- as a fixing element of the rotor part of the seal, half rings are used that cover the shaft without causing local deformations of the shaft surface, as in the case of using locking screws;
- the maximally movable element is made e rotating (alternative layout according to API 682);
- springs are removed from the product being compacted;
- friction pair rings:
- hydraulically unloaded;
- have a simple rectangular shape with a small number of shaped elements (grooves, grooves), which minimizes deformation of the rings due to pressure;
- the sliding surface is made at the minimum possible diameter in order to reduce the sliding speed in a friction pair, for example, a seal on a 60 mm shaft has a sliding speed 12.5% lower than a seal with an ONP-60 friction pair, which, with a pump operating time of 4000, provides the difference distance traveled – 4161 km;
- unification of spare parts for all brands of seals of the same standard size (for one shaft size), friction pair rings, rubber goods, springs are completely interchangeable.
MECHANICAL SEALS FOR MIXING DEVICES
We produce single and double mechanical seals for mixing devices with various seal mounting options (top, side, bottom).
The production program includes special designs of mechanical seals for installation on enameled devices.
If it is necessary to reduce the radial runout of the shaft in the area where the seal is installed, a bearing block is used in the design, rigidly connected to the seal block, which takes up the radial load.
WE PRODUCE AND SUPPLY SPARE PARTS
For mechanical seals according to drawings or samples provided by the Customer:
- friction pair rings;
- sliding bearings made of super-hard materials;
- secondary seals;
- springs;
- other details.
