CN1588596A

CN1588596A - Self lubricating isolated switch cotnactor and coating method for contactor surface

Info

Publication number: CN1588596A
Application number: CN 200410051289
Authority: CN
Inventors: 许晓欢
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-08-26
Filing date: 2004-08-26
Publication date: 2005-03-02

Abstract

The invention is a method of coating the surface of a self-lubricating isolating switch contact, based on a conductive metal contact body and it includes the steps: a. preprocessing the metal surface of the contact body; b. coating a graphite-containing coat at the active contact part of the preprocessed metal surface. And the isolating switch contact processed by the invention contacts well, opens and closes reliably, and has a wearable life able to reach above 10000 times and needs no maintaining. It largely increases operating stability and economical property.

Description

Self-lubricating isolation switch contacts and the contact surface of the coating method

TECHNICAL FIELD The present invention relates to a process of impregnation and coating of graphite coated with silver plating methods Alloys of graphite, but also post-treatment process of the coating; particularly to an impregnation method or silver coated graphite Graphite treated alloy isolation switch contacts.

BACKGROUND ART In such devices and switching devices and the operation of the practical application, the contact, contact, plug Other components often requires both a good electrical conductivity, wear resistance and lubricity, the prior art generally use silver material Material or brass coated with grease after silver plating way to meet this requirement. But the use of silver material cost is too high, After using silver plating copper material coated grease approach has its own shortcomings can not be overcome in order to 12KV-550KV Outdoor isolation switch as an example: The device is the key equipment in power transmission systems, the national grid in the hundreds of thousands of sets of Run using its existing contact system technology is generally coated with copper contacts silver grease after the solution conductivity And wear life, this approach although tests in the factory through (painted once every 50 times grease), But in the actual run outdoors in the sand adhesions often due to grease, resulting in poor contact and acceleration silver contact layer grinding Loss, a long time also caused oil to dry contacts being exposed, can cause line errors. If there is no grease will make Silver layer wear quickly affect the conductivity of the contact, it will also cause the line failure, so must always be maintained and Maintenance, and high voltage lines do not allow the repair and maintenance of frequent power outages, the presence of the device which is currently one of the major defects. ...

1 requirements to isolate the switch contacts lubricity and abrasion life: ≥ 2000 times.

2 required to isolate the conductive switch contacts, main circuit resistance to IEC international standards.

3 requirements to achieve high isolation switch temperature rise test standard: ≤ K65.

Thus greatly improving the life of outdoor isolating switch and greatly reduce the maintenance workload.

The invention is illustrated by the following technical solutions to achieve,

Implementation of a self-lubricating surface coating method for isolating switch contacts, conductive metal contacts on the body, said method Comprising the steps of:

a. pair of contacts of the metal surface pretreatment body;

b. contacts in the pretreated metal parts on top of the moving contact surface coated with graphite coating.

Said contact metal is copper, step a pair of contacts of the metal surface pretreatment body means the body of the contact Over the entire metal surface generates a low resistivity, anti-oxidation intermediate layer, the intermediate layer is silver and its alloys, plating intermediate Using conventional cyanide silver plating layer, the subsequent steps include:

a. moving in the middle layer of the surface of the contact area with 10 to 14 # corundum sandblasting, or spark

For scarification;

b. the treated surface of the intermediate layer with the movable contact part of the flame spray gun spraying speed ≥ 80μm thickness Silver or silver alloy;

c. immersed graphite liquid;

d. surface finishes.

If said contact metal is an alloy of copper, which will greatly improve the oxidation resistance, the pair of contacts of step a Body pretreated metal surface is the surface of the contact metal finishing machine, without having to silver, the subsequent Step comprises:

a. metal surface in the contact portion with the movable contact 10 to 14 # corundum sandblasting, or utilization Spark for scarification;

b. the treated metal surface of the contact portion with the movable contact-speed flame spraying gun thickness ≥ 80μm Silver or silver alloys;

c. immersed graphite liquid;

d. surface finishes.

In addition to using the above graphite solution dipping method, the body of the contact surface of the conventional all-metal cyanide silver works Arts plating intermediate layer, an intermediate layer can also contact site on the dynamic Plated 80μm thick with silver graphite together Gold coating;

With the device comprising: mixing the plating tank with circulation, DC pulse plating power;

Materials include: conventional silver plating solution, silver alloy plate and nanoscale graphite.

With the above graphite solution dipping method, a graphite liquid include: ultra-fine graphite powder, a microcrystalline wax and a solvent, The weight ratio of formulation:

Fine graphite powder 10 ~ 30%

10 to 30% microcrystalline wax

Solvent 40 to 80%

The solvents include: acetone, butyl acetate and xylene, the weight ratio of formulation:

40 ~ 60% acetone

10 to 30% butyl acetate

20 to 40% xylene

The graphite solution dipping step c includes the following process operations:

a. microcrystalline wax into ≤ 60 ℃ dissolved into a solvent;

b. adding ultra-fine graphite powder and stir;

c. the intermediate layer plated contacts implant placement;

d. pressure retention time less than 10 minutes.

After step d of the surface treatment process includes the following operations:

a. would have contacts with graphite coating body for air drying;

b. the graphite coating surface finishing smooth;

c. part in non-contact protective acrylic spray paint.

Manufactured by the above method self-lubricating isolation switch contacts, the contact member including a conductive metal, conductive metal Contact body on top of the middle layer, the intermediate layer is above the moving contact parts with graphite coating.

Said contact body is copper and its alloys; said intermediate layer is silver and its alloys, tin or their alloys; described in Thickness between 10 ~ 20μm; said graphite-containing coating thickness ≥ 80μm.

Compared with the prior art, the present invention is treatment processing techniques good contact isolation switch contact, opening and closing can be Reliable, resistant to wear life of up to 10,000 times more, no maintenance, greatly improving the stability and operation of disconnectors Economy.

BRIEF DESCRIPTION OF DRAWINGS FIG 1 is a self-lubricating coating isolation switch contacts the surface of the graphite layer Fig.

The following specific embodiments with the accompanying drawings and embodiments of the present invention is described in further detail.

Figure 1: the implementation of a self-lubricating surface coating method for isolating switch contacts, conductive metal contacts on Body 10, said method comprising the steps of:

a. the body 10 contacts the metal surface pretreatment;

b. in the pretreated metal surface contact body 10 above the moving contact parts coated with graphite coating 30.

Said contact metal is copper body 10, step a body 10 contacts the pair of metal surface pretreatment means All-metal contacts over the surface of the body 10 generates a low resistivity, anti-oxidation intermediate layer 20, intermediate layer 20 is silver, and An alloy, the intermediate plating layer 20 using conventional cyanide silver plating process, the subsequent steps include:

a. surface of the intermediate layer 20 is movable contact parts with 10 to 14 # corundum sandblasting, or electrical fire Flowers for scarification;

b. the treated surface of the intermediate layer 20 with the movable contact portions speed flame spraying gun thickness ≥ 80μm Silver or silver alloys;

c. immersed graphite liquid;

d. surface finishes.

If the contact member 10 of metal is copper alloy, then in step a body 10 of the pair of contacts into the metal surface Pretreatment of the contact line of the body 10 is a metal surface finishing machine, without having to silver, the subsequent steps include:

a. metal surface of the contact body 10 with the movable contact parts 10 to 14 # corundum sandblasting, or utilization Spark for scarification;

b. the treated metal surface on the contact body 10 with the speed of the moving contact part of the flame spraying gun ≥ 80μm thick Degree of silver or silver alloy;

c. immersed graphite liquid;

d. surface finishes.

In addition to using the above graphite solution dipping method, the body of the contact surface of the conventional all-metal cyanide silver works Arts plating intermediate layer 20, the layer 20 can also be in the middle of moving parts in contact with the plating on silver plated 80μm thick Graphite alloy coating 30;

Fine graphite powder 10 ~ 30%

10 to 30% microcrystalline wax

Solvent 40 to 80%

Of which:

Scenario 1

Ultrafine graphite powder 20%

Microcrystalline wax 20%

Solvent 60%

Scenario 2

Ultrafine graphite powder 10%

Microcrystalline wax 10%

Solvent 80%

Scenario 3

Ultrafine graphite powder 30%

Microcrystalline wax 20%

Solvent 50%

40 ~ 60% acetone

10 to 30% butyl acetate

20 to 40% xylene

Of which:

Scenario 1

40% acetone

Butyl acetate 30%

Xylene 30%

Scenario 2

60% acetone

Butyl acetate 10%

Xylene 30%

Scenario 3

60% acetone

Butyl acetate 30%

Xylene 10%

The graphite solution dipping process operations include:

a. microcrystalline wax into ≤ 60 ℃ dissolved into a solvent;

b. adding ultra-fine graphite powder and stir;

c. the intermediate plated layer 20 into the contact body 10;

d. pressure retention time less than 10 minutes.

The surface post-processing operation includes the following processes:

a. would have been with graphite coating 30 of the contact body 10 for hot air drying or natural drying;

b. the graphite surface finishing smooth coating 30;

c. part in non-contact protective acrylic spray paint.

Shown in Figure 1, with the above method of self-lubricating isolation switch contacts, the contacts of the conductive metal member 10 to the Is an intermediate layer 20, the intermediate layer 20 is above the moving parts in contact with the graphite coating 30.

Said contact body 10 are copper and its alloys is the best; said intermediate layer 20 of silver and its alloys is the best, intermediate Layer 20 may also be used tin and their alloys; wherein the thickness of the intermediate layer 20 of the top 10 ~ 20μm; wherein Graphite-containing coating thickness of 30 best should ≥ 80μm.

Another embodiment of the invention to, for example, if the contact member 10 and the metal is aluminum alloy, the Intermediate layer 20 is silver and its alloys, plating intermediate layer 20 before, we must first pair of contact body 10 first be pre-plated metal surface Silver or dip zinc coating, and then on which subsequent process operation.

The process of the present invention and products according to the following criteria:

GBn67-83 Precious metals and their alloys wire

GB/T3814-1999 light industrial products and chemical treatment of metal plating layer appearance quality measurements

GB/T3835-1999 light industrial products and chemical treatment of metal plating thickness testing methods: β-ray Reverse Scattering method

GB/T6462-86 metal and oxide coating thickness - Microscopical method

GB9793-88 thermal spray zinc and zinc alloy coatings

GB9794-88 thermal spray zinc and zinc alloy coated test methods

Intermediate layer 20 silver appearance of the coating and inspection:

In the daytime natural light source greater than 300 lux light intensity conditions visual inspection was gray, and the boundary Neat, smooth surface, uniform, smooth, seamless coating, no glitches, no local shedding, no significant sediment bulge, No serious knock, injury scratch marks; using the measured roughness tester: coating the surface roughness Ra ≤ 20μm.

Thickness measuring method:

Silver contacts the work surface average coating thickness of not less than 80μm, the minimum thickness of not less than 50μm.

Electrolysis: Use the electrolytic thickness, in a sample product measured directly on the surface of the coating.

β-ray scattering method response: According to GB/T3835-1999 "light industrial products and chemical treatment of metal plating layer thickness Degree test methods: β-ray backscatter method "test for detection.

Metallographic method: According to GB/T6462-1986 "metals and metallic coating thickness - Microscopical method" Pilot testing. This method can be used as thickness measurement arbitration.

Bond strength test:

Coating and binding properties of the substrate according to GB9794-88 binding in Chapter 5 Test method implemented.

When a cross-cut test method, after the test, the box and the substrate of the coating may come off.

Tensile test specimens for use, at least for five samples after the test, the bonding strength of one of the sample values are not Less than 5.9N/mm²(0.6kgf/mm ²)。

Hardness test:

According to GB/T5270-1986 "light industrial products metal coating hardness test methods - microhardness method" test Testing. The microhardness of the coating should be greater than HV150 or more.

Mechanical life and the main loop resistance test:

GW series products used in contacts to GW4G-126/1250 isolating switch-standing contacts, for example, Tribological mechanical life of no less than 10,000 times, the main circuit resistance value should meet technical requirements.

Example:

The outdoor isolating switch after copper contacts silver, silver alloys for thermal spraying and then dip hard graphite liquid processing, shape Into silver graphite composite layer. It has a low coefficient of friction and good electrical conductivity. Currently in GW4G-126/630, GW4G-1250, GW4G-2000, GW5G-126/630, GW5G-1250; GW5G-2000 type outdoor high-voltage AC isolation Switch on the application. By the Henan Provincial High Voltage Apparatus Research Institute at GW4G-126/1250 type outdoor high-voltage AC isolated Off on testing as follows:

Inspection by:

One, QTQ.520.010 GW4G-126/1250 type outdoor high-voltage AC isolation switch technical conditions;

Two, QTQ.192.010 GW4G-126/1250 type outdoor high-voltage AC isolation switch prototype qualification program.

Table 1 Self-lubricating silver isolation switch contacts open and close operations 10,000 times loop resistance of inspection records:

Product Name: Self-lubricating silver plated contacts isolation switch Specifications Model: ZC-1
						No.	Test items		Technical Requirements	Test results	Individual conclusions
1	After opening the minimum air insulation gap (mm)		≥1250	1254	Qualified	No.	Test items		Technical Requirements	Test results	Individual conclusions
1	After opening the minimum air insulation gap (mm)		≥1250	1254	Qualified	2	Main circuit resistance Measurement (μΩ)	Life before the rise ago	≤100	82	Qualified
Life before the temperature rise after	≤100	80	Qualified					Life before the rise ago	≤100	82	Qualified
Life before the temperature rise after	≤100	80	Qualified	Life after the temperature before	≤100			78	Qualified
Life after the temperature rise after	≤100	77	Qualified	Life after the temperature before	≤100			78	Qualified
Life after the temperature rise after	≤100	77	Qualified	3	Mechanical life test Test			Sample of 10000 Second operation test, the Operating sequence, the number of And asked to see Schedule 1.	Move isolation switch As should be normal, Contact, finger No exposed copper.	Move isolation switch As normal, touch Head, fingers without Exposed copper.	Qualified
				3	Mechanical life test Test						Qualified

Schedule 1

Sequence	Closing voltage (%)		Points closing times
	Closing voltage (%)		Points closing times					Tripping	Closing	Closing...	Closing...	Third Round	Fourth Round	Fifth Round
	Co-15s-of-15s	120％	110％	500	500	500	500	Tripping	Closing	Closing...	Closing...	Third Round	Fourth Round	Fifth Round	500
Co-15s-of-15s	Co-15s-of-15s	120％	110％	500	500	500	500	100％	100％	1000	1000	1000	1000	1000	500
Co-15s-of-15s	Co-15s-of-15s	65％	85％	500	500	500	500	100％	100％	1000	1000	1000	1000	1000	500
Total combined, sub-frequency	Co-15s-of-15s	65％	85％	500	500	500	500	10000							500

Table 2 Temperature rise test

Product Name: Self-lubricating silver plated contacts isolation switch Specifications Model: ZC-1
						Test current: 1250 (A)	Test Phase: 1	Current Frequency: 50 (Hz)
Current Frequency: 50 (Hz)...				Current Frequency: 50 (Hz)...		Test current: 1250 (A)	Test Phase: 1	Current Frequency: 50 (Hz)
Current Frequency: 50 (Hz)...				Current Frequency: 50 (Hz)...		Data measured temperature (K)
The measurement site Number	Before the durability test machine	Mechanical durability test	Allowed temperature rise (K)		Individual conclusions	Data measured temperature (K)

1	19.31	24.25	50	Qualified
1	19.31	24.25	50		2	20.36	22.01	50
3	19.24	23.61	60		2	20.36	22.01	50
3	19.24	23.61	60		4	23.65	27.61	65
5	24.44	26.89	65		4	23.65	27.61	65
5	24.44	26.89	65		6	24.21	26.12	65
7	20.01	19.21	65		6	24.21	26.12	65
7	20.01	19.21	65		8	18.71	21.62	50
9	17.63	20.04	50		8	18.71	21.62	50
9	17.63	20.04	50			Ambient temperature: 27.8 ℃	Ambient temperature: 30.4 ℃
Note: 1. Temperature measuring point see Figure 1. 2 points 1 and 9 are connected to the aluminum rafts at 1 m from the terminal point, requiring respectively points 2 and 8 Temperature difference of no more than 5K.						Ambient temperature: 27.8 ℃	Ambient temperature: 30.4 ℃

Practice has proved that, using the present technique treatment process isolation switch contact in good contact, opening and closing reliable, wear Loss of life of up to 10,000 times more, no maintenance, has been in the nation's largest manufacturer of high-voltage isolation switch Outdoor high-voltage AC isolation switch products are applied, the practical application of good. Models GW4G-126/630, GW4G-1250, GW4G-2000, GW5G-126/630, GW5G-1250; GW5G-2000. The present invention greatly improves the Isolation switch operating stability and economy.

Claims

1 a self-lubricating surface coating method for isolating switch contacts, the contacts on the conductive metal body (10), characterized in that, Said method comprising the steps of:

a. pair of contact body (10) of the metal surface pretreatment;

b. contacts in the pretreated body (10) movable contact portion on the metal surface coated with graphite coating (30).

(2) as claimed in claim 1, wherein the isolation switch contact surface self-lubricating coating, characterized in that: said contact body (10) metal is copper, step a pair of contacts of said body (10) pre-treatment of the metal surface is of the contact body (10) Over the entire metal surface generates a low resistivity, anti-oxidation intermediate layer (20), an intermediate layer (20) is silver and Alloy, plated intermediate layer (20) using conventional cyanide silver plating process, the subsequent steps include:

a. the intermediate layer (20) with the surface of the movable contact parts 10 to 14 # corundum sandblasting, or spark For scarification;

b. after the treatment the intermediate layer (20) of the movable contact portion with the surface speed of the flame spray gun in spraying thickness ≥ 80μm Silver or silver alloys;

c. immersed graphite liquid;

d. surface finishes.

3 according to claim 1, wherein the isolation switch contact surface self-lubricating coating, characterized in that: said contact body (10) metal is an alloy of copper, step a pair of contacts of said body (10) pre-treatment of the metal surface is on the touch Head body (10) metal surface finishing machine, the subsequent steps include:

a. the contact member (10) movable contact parts metal surface with 10 to 14 # corundum sandblasting, or utilization Spark for scarification;

b. contacts after the treatment body (10) movable contact portion with the metal surface of the flame spray gun spraying speed ≥ 80μm thick Degree of silver or silver alloy;

c. immersed graphite liquid;

d. surface finishes.

As claimed in claim 1, wherein the isolation switch contact surface self-lubricating coating, characterized in that: said contact body (10) metal is copper, step a pair of contacts of said body (10) pre-treatment of the metal surface is of the contact body (10) Over the entire metal surface generates a low resistivity, anti-oxidation intermediate layer (20), an intermediate layer (20) is silver and Alloy, plated intermediate layer (20) and subsequent steps of:

a. the contact body (10) on the surface of all-metal cyanide silver plating process using conventional intermediate layer (20);

b. the intermediate layer (20) of the movable contact portion on a 80μm thick plating silver plated graphite alloy coating layer (30); With the device comprising: mixing the plating tank with circulation, DC pulse plating power;

5 according to claim 2 or 3, wherein the self-lubricating coating isolation switch contact surface, characterized in that: said stone The ink include: ultra-fine graphite powder, a microcrystalline wax and a solvent, the weight ratio of formulation:

Fine graphite powder 10 ~ 30%

10 to 30% microcrystalline wax

Solvent 40 to 80%

As claimed in claim 5, wherein the self-lubricating coating isolation switch contact surface, characterized in that: said solvent bag Include: acetone, butyl acetate and xylene, the weight ratio of formulation:

40 ~ 60% acetone

10 to 30% butyl acetate

20 to 40% xylene

As claimed in claim 2 or 3, wherein the isolation switch contact surface self-lubricating coating, characterized in that: step c The graphite solution dipping process operations include:

a. microcrystalline wax into ≤ 60 ℃ dissolved into a solvent;

b. adding ultra-fine graphite powder and stir;

c. the intermediate plated layer (20) of the contact body (10) into;

d. pressure retention time less than 10 minutes.

As claimed in claim 2 or 3, wherein the self-lubricating coating isolation switch contact surface, characterized in that: step d The surface post-processing operation includes the following processes:

a. would have with graphite coating (30) of the contact body (10) hot air drying or natural drying;

b. graphite coating (30) smooth surface finishing.

9 A self-lubricating isolation switch contact, the contact including a conductive metal member (10), characterized in that: a conductive metal The contact body (10) above the intermediate layer (20), said intermediate layer (20) on the movable contact portion coated with graphite Layer (30).

A process according to claim 9, wherein the self-lubricating isolation switch contact, characterized in that: said contact member (10) is Copper and its alloys; said intermediate layer (20) is silver and its alloys, tin or their alloys; said intermediate layer (20) The thickness of 10 ~ 20μm; said graphite-containing coating (30) has a thickness ≥ 80μm.