Introduction of technical department - seal (two)

We have introduced the rubber seal ring (O ring, Y ring, O ring), this period mainly introduces our company commonly used combination seal

1.V shape sealing ring

The cross section of the V shape sealing ring is V, which is mainly used for the reciprocating movement of the hydraulic cylinder piston and the piston rod, and is composed of a pressure ring, one or two V shaped sealing rings and a supporting ring.

Material: used in 100 DEG C, V sealing ring by clamping the nitrile rubber fabric reinforced, supporting ring, ring with cloth or nylon; at 100 DEG ~200 DEG or containing phosphate ester hydraulic oil is used under the environment of V sealing ring made of polytetrafluoroethylene and fluorine rubber, pressure ring, bearing the use of PTFE ring. This kind of sealing ring adopts open installation.

Features: 1 good sealing effect, long service life;

2 suitable for axial and radial vibration and eccentric load;

3 able to withstand high pressure and constant pressure;

4 easy to install and disassemble

Working conditions: pressure: 40MPa

Speed: 0.5m/s

Temperature: -30 C ~ +200 C

Medium: hydraulic oil, emulsion and water

2 coaxial seal type

Coaxial sealing ring, commonly known as slip ring type combined seal ring, according to its use, can be divided into the piston with a coaxial seal ring (grid) and the piston rod with a coaxial seal (seal).

The utility model relates to a single acting sealing ring for a piston rod, which is composed of an abrasion resistant polytetrafluoroethylene PTFE ring and a O shaped rubber sealing ring. The O ring provides sufficient seal preload and compensates for the wear of the PTFE ring. PTFE friction coefficient, static and dynamic friction coefficient. The utility model is suitable for the oil cylinder piston rod seal of high and low speed reciprocating motion and high pressure system. The diameter of the shaft is less than 30 of the size of the shaft.

Working conditions: voltage: 0 ~ 60MPa

Reciprocating speed: less than 0.5m/s

Operating temperature: -30 DEG C to +200 DEG C (depending on the material of the O ring)

Working medium: hydraulic oil, water

Performance: 1 very high pressure stability under pressure and harsh conditions;

2 good thermal conductivity

3 high resistance to extrusion

4 high wear resistance, low friction, non stick slip phenomenon

The mesh ring is a double acting piston ring, which is composed of an antiwear PTFE ring and a O shaped rubber sealing ring. The O ring provides sufficient seal preload and compensates for the wear of the PTFE ring.

The working conditions and performance of the grid are consistent with those of the seal.

When installing the seal, one side of the sealing lip should be noted to the side of the pressure chamber. In addition, stepseal and glyd ring in the ring before the assembly, should be 120 degrees in the oil bath for 10 minutes. When sealing the sealing ring, the sealing ring is bent into the shape as shown in the figure, and then loaded into the groove of the hydraulic cylinder.

Dust ring

The dustproof ring is arranged on the outer side of the piston rod or the plunger seal, which is used for preventing the external dust, sand and other foreign bodies from entering the hydraulic cylinder.

At present, the commonly used dust ring, generally lip, a skeleton type, no skeleton type, double lip. To the skeleton of the most commonly used dust ring, its working state as shown in figure. The utility model is characterized in that the supporting part has the advantages of large size, good strength, no need of additional skeleton, simple structure, convenient assembly and disassembly, and good dust removing effect.

Double lip dustproof ring, which can prevent dust and leakage. When the piston rod is extended outwards, the oil film sealing tape out on the piston rod through the main, namely leakage resistance lip scraping, will not continue to take out at the same time, foreign body external dust and difficult to stick on the piston rod and the dust ring is easily removed, therefore, improves the dust the effect of.

Seal installation groove form:

1 piston rod seal

Generally speaking, there are two types of grooves:

A, open groove, open along the axial direction

The utility model relates to a B, a closed groove, and an annular groove is processed on the cylinder body or the end face

General multi seals require open trench, such as V shaped ring

Single seal, such as Y - ring and seal, can be installed in a closed groove, but the diameter is too small, the need for open trench. According to the design of the oil cylinder, the low pressure side of the seal has more or less clearance. Under high pressure, the material at the root of the seal may be squeezed into the gap, causing damage to the seal. The maximum permissible clearance is listed in the sample of the seal, and the actual gap should not exceed this value.

When the seal is installed, the edges and sharp edges may damage the seal, so the piston rod and groove shall be provided with chamfer and fillet.

2 piston seal

A, open trench, open along the axial direction

B, closed groove

The V shaped ring requires an open groove, and the common seal can be installed in a closed groove through its elastic extension.

Because the sealing ring must be pre tightening force, so the diameter of the piston seal after installation should be larger than the diameter of the cylinder, the piston installation, in order to prevent damage to the seal, the cylinder should be chamfered. Chamfer dimensions in seal product samples.

Introduction and use characteristics of sealing materials

At present, we commonly used seal material:

A. polytetrafluoroethylene (PTFE): low friction coefficient, good self lubricity, is not sticky, almost all of the substances are not adhered on the surface, weatherability and excellent thermal properties, resistant to almost all chemicals and solvents, the use of a wide range of temperature. Operating temperature: -250 C ~ +260 C.

B. polyurethane (PU): high strength (up to 40MPa), superior wear resistance