The name of mine cable and the principle of cable naming

Mine cable is short for fire-retardant cable for coal mines. According to the provisions of the industry standard “Fire-retardant cable for coal mines” promulgated by the State Coal Industry Bureau, the naming content of the mining cable, that is, the meaning of the mining cable model is as follows.

First, the cable's name consists of eight parts:

The first part is series code M, the first prefix of the pinyin of coal.

The second part is the use of characteristic code, reflecting the occasions used by the cable. The meanings of the letters are as follows: C, for coal mining machine; D, for low-temperature environment; M, cap lamp; Y, for coal mining equipment (moving); Z, for electric drilling.

The third part is the structural feature code, indicating the structural characteristics of the cable. The meanings of the letters are as follows: B, weaving strengthening; J, with monitoring core; P, non-metallic shielding; PT, metal shielding; Q, lightweight;

The fourth part is the material feature code, and E means that the insulation or sheath is made of elastomer material. This part is omitted when both rubber and rubber are used. E, elastomer material.

The fifth part is rated voltage U0/U(KV).

The sixth part is the representation of the number of power cores * nominal cross-sectional area. The two are connected by a multiplication sign and the unit is square millimeters.

The seventh part is the representation of the number of ground cores* nominal cross-sectional area. The two are connected by a multiplication sign and the unit is square millimeters.

The eighth part is the representation of the number of auxiliary cores * nominal cross-sectional area. The two are connected by a multiplication sign and the unit is square millimeters.

Pressure Relief Valves

Pressure relief valves has two types, direct operated type and pilot operated type.

DBD pressure relief valves are direct operated type relief valves. They are used to limit the pressure in a hydraulic system. DBD type relief valves offer line contact sealing for minimal leakage at closure and a full array of pressure capacities are available.

Pressure control valves of type DB are pilot operated pressure relief valves. They are used for the limitation of the operating pressure. Pressure relief valves basically consist of a main valve with main spool insert and pilot valve with pressure adjustment elements.

Features:

l  Sizes 6 to 20

l  For threaded connection ([G")

l  As Cartridge Valve ([K")

l  Optional adjustment types: 
- Screw with hexagon socket and protective cap 
- Rotary knob / hand wheel

Pressure Relief Valves

Pressure Relief Valves,Relief Valve,Rexroth Pressure Relief Valve,Pilot Relief Valve

Jinan Longli Hydraulic Device Co.,Ltd , http://www.longlihydro.com