CN2775433Y

CN2775433Y - Straight through safety valve

Info

Publication number: CN2775433Y
Application number: CN 200420054211
Authority: CN
Inventors: 杨渠忠
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-12-09
Filing date: 2004-12-09
Publication date: 2006-04-26
Anticipated expiration: 2014-12-09

Abstract

The utility model relates to a straight through safety valve which belongs to a safety valve of a heating device of an oil field. The utility model comprises a valve seat (3) installed on the upper end of a steel pipe (7), wherein the lower end of the valve cover (1) is fixed on the upper end of the valve seat (3) through a sealing ring (2), and a heavy bob (8) is fixed on the upper end of the valve cover (1) through a screw rod (9) and a nut (11); both ends of a pin shaft (4) are installed on two symmetrical supports (5) which form a whole hole with the outside the valve cover (1) through split pins (6); a positioning block (12) is fixed outside the valve seat (3) below the supports (5). The straight through safety valve solves the problems of safety valves of furnace bodies under the condition that boiler furnaces such as water jacket furnaces, vacuum phase transition furnaces, etc. have abnormal pressure; namely under the condition that the boiler furnaces such as water jacket furnaces, vacuum phase transition furnaces, etc. have abnormal pressure in oil fields, boiler drums can be straightly communicated with the atmosphere instantly to carry out timely discharge and the safety of the boiler furnaces can be ensured.

Description

The straight-through type safety valve

Technical field

Straight-through type safety valve of the present utility model belongs to oil field heating equipment safety valve, comprises the safety relief safety valve of water jacket furnace, phase transition of vacuum stove, minute-pressure water-heating furnace.

Background technique

Be extensive use of water jacket furnace, phase transition of vacuum stove, minute-pressure water-heating boiler, steam boiler at present in the oil field.Wherein particularly water jacket furnace and phase transition of vacuum stove exist the potential safety hazard that can not solve as the special-purpose heating equipment of crude oil and rock gas heating always.The water jacket furnace housing generally moves under normal pressure or minute-pressure power state, and the phase transition of vacuum stove moves under micro-vacuum state, generally moves between-0.05MP to 0.05MP.For a long time, people generally believe that this two kinds of type of furnaces are very safe, are a kind of misunderstanding in fact.Though because the design pressure is very low in the housing, approach normal pressure, often pressure is very high for the medium of drum inner coil pipe operation, and for example well head rock gas coil pipe pressure reaches 60MP, in case coil pipe takes place to reveal even fracture accident, will explode immediately.

The 4.0.4 bar is mentioned in SY0031-95 " petroleum industry oven safety specification " clause explanation: " field produces facts have proved, water jacket furnace is least safe a kind of in the oven.According to on-scene investigation, certain oil field 0.46MW water jacket furnace explosion time, heating coil fly out tens of rice far after passing the roof cement board.Its explosion cause think by analysis the weld seam of oil coil lack of penetration due to.Because weld seam is lack of penetration, cause stress raisers and crack, as time goes by, crackle gradually to the weld joint along stretching.When it holds when can't stand working pressure, and produce rupture failure, cause coil pipe pressure moment of 6.4MP to be released among design pressure is the housing of 0.4MP, cause the water jacket furnace case fragmentation along the weld seam hoop.”

Mainly use Direct spring loaded safety valve for the water jacket furnace safety relief at present; Or the phase transition of vacuum stove mainly uses gravity type safety valve solenoid valve.Owing to a large amount of reveal or during fracture accident occur at coil pipe, the hysteresis of clean boot and the instantaneous high pressure that produces can't solve, therefore present water jacket furnace and phase transition of vacuum stove exists potential safety hazard.

The model utility content

The purpose of this utility model is to solve the safety problem that occurs (comprising the coil pipe crack conditions) body of heater under the situation of unusual superpressure when water jacket furnace or phase transition of vacuum stove.

Of the present utility model to the effect that having designed directly led to the atmospheric type safety valve, occurs under the situation of unusual superpressure at water jacket furnace or phase transition of vacuum stove, can moment allow drum lead directly to atmosphere, in time drains, and guarantees boiler safety.

The composition of this straight-through type safety valve comprises the valve seat that is contained on the steel pipe, the valve gap lower end is fixed on the valve seat by seal ring, weight is fixed on the upper end of valve gap by screw rod and nut, the bearing pin two ends are contained on the bearing with the valve gap outside two symmetries in aggregates by cotter pin, and limiting stopper is fixed on the valve seat outside of bearing below.

Main technical principle of the present utility model: utilize lever principle, when the drum internal pressure reached the design drainage pressure, moment was opened valve gap, allows drum lead directly to atmosphere, drains by the heavy caliber escape pipe.In opening transients, ingenious utilization principle of moments allows unlatching pressure be reduced to 1/10 drainage pressure setting value rapidly from the drainage pressure value of setting.That is to say that in the unlatching transients of safety valve, the needed cracking pressure of valve gap diminishes gradually, so just is easy to open, the unlikely high pressure that produces moment.

Major technique feature of the present utility model is that valve gap moment to open required pressure be to diminish gradually, unlikely generation instantaneous pressure; Be straight-through atmosphere after valve gap is opened, be convenient in time hesitate gas; After accident treatment, when the drum internal pressure drops to design load, the topped automatically and sealing of valve gap.

Therefore the utility model compared with prior art has following advantage:

1, moment opens, and the required cracking pressure of valve gap diminishes gradually, unlikely generation instantaneous pressure.

2, be straight-through atmosphere after valve gap is opened, be convenient to timely drainage.

3, after accident treatment, when the drum internal pressure drops to design load, the topped automatically and sealing of valve gap.

Description of drawings

Fig. 1 is a straight-through type safety valve structure plan view.

Fig. 2 is a straight-through type safety valve structure left view

The number in the figure title:

1, valve gap, 2, seal ring, 3, valve seat, 4, bearing pin, 5, bearing, 6, cotter pin, 7, steel pipe, 8, weight, 9, screw rod, 10, packing ring, 11, hexagon nut, 12, limiting stopper.

Embodiment

Fig. 1 is the structural representation of this straight-through type safety valve, comprise the valve seat 3 that is installed on steel pipe 7 upper ends, valve gap 1 lower end is fixed on valve seat 3 upper ends by seal ring 2, weight 8 is fixed on the upper end of valve gap 1 by screw rod 9 and packing ring 10 and nut 11, bearing pin 4 two ends are contained on the bearing with valve gap 1 outside two symmetries in aggregates by cotter pin 6, and limiting stopper 12 is fixed on the outside of valve seat 3 of bearing and below.

Its action principle is: superpressure steam or other medium act on the valve gap 1 by steel pipe 7, weight 8 weight blocks are arranged above the valve gap 1, weight 8 weight blocks are fixed with valve gap 1 by screw rod 9, packing ring 10, hexagon nut 11, when the pressure that acts on valve gap 1 when steam in the drum or other medium surpasses the gross weight of weight 8 weight blocks and valve gap 1, valve gap 1 is opened, in the process of opening, weight 8 and valve gap 1 are around with bearing pin 4 being the motion counterclockwise of fulcrum do.In making counterclockwise movement process, the gravitational moment of weight 8 and valve gap 1 diminishes gradually, be very easy to open, and after being opened to several angle, 1 limited 12 braking of valve gap.After the pressure release of drum internal pressure, when reaching design pressure, rely on the topped automatically and sealing of gravitational moment of weight 8 and valve gap 1.Sealing system is made up of valve gap 1 and O RunddichtringO 2, and O RunddichtringO 2 is fixed on the valve seat 3, and bearing pin 4 is fixing by bearing 5, cotter pin 6, and in order to rotate flexibly and sealing effect, sealing surface valve gap 1 and bearing pin 4 all use stainless steel material.

Claims

1, a kind of straight-through type safety valve, it is characterized in that, comprise the valve seat (3) that is contained on steel pipe (7) upper end, valve gap (1) lower end is fixed on valve seat (3) upper end by seal ring (2), weight (8) is fixed on the upper end of valve gap (1) by screw rod (9) and nut (11), bearing pin (4) two ends are contained on the bearing (5) with valve gap (1) outside two symmetries in aggregates by cotter pin (6), and limiting stopper (12) is fixed on valve seat (3) outside of bearing (5) below.