DST Tools 3 7/8" Big John Jar 

General

Big John Jar is also called Hydraulic Jar, is included as part of a toolstring to help remove stuck tools.

The jar helps free a stuck tool or toolstring by resisting a pull on the workstring. When the workstring is stretched by the pull, tension in the jar is released and an upward impact is delivered to the stuck tool.

Features and Benefits

•  Design of the hydraulic system ensures long life with little maintenance.

•  Rig time is reduced.

•  Jar can be recocked rapidly.

•  Jar time delay is adjustable.

•  Amount of pull to trip the jar can be varied within the limits of the time-delay system.

Operation

The temporary resistance that powers the jar is provided by a hydraulic time-delay system. Resistance is released when the metering sleeve inside the jar moves into a bypass section of the outer case. This action allows the special hydraulic oil to bypass rapidly.

The time delay required to release the temporary resistance varies in relation to the weight of the pull. For example, a light pull requires more time for release than a hard pull. When tools below the jar are stuck, a steady pull applied to the jar creates an upward impact blow to the string. The jar can be recocked when the string is set down.

Pictures

About Us

Xi'an Kingwell Oilfield Machinery Co.,Ltd is a professional supplier for oilfield products according to the API standard.

Our products have exported to USA, Canada, Egypt, India and UEA, etc with 40 FCL containers per month. Now, with high quality and short supply and good service, our products have got good reputation home and abroad .

Here we got some prise as follows.

Certifications

Kingwell is a CNPC & SINOPEC & BV certified company, having all the Quality Systems in place for design, planning, manufacturing and quality monitoring & traceability to ensure our products match the highest quality standards.

We test our products strictly according to the NACE MR 0175-2002 Standard and our quality assurance period is 12 months.

Certificates endorsed by DNV/BV/ABS and Documents we can supply with the shipments:

1. Pressure Test Certificate with Graph and time recorded.

2. Function Test   

3. Rubber Products NACE Compliance   

4. Material Mill Certificate and treatment characteristics

5. H2S Compliance   

6. Service Manual

7. Parts Manual

8. Testing Procedures.

9. Open up type tool drawing for dressing purpose– if any.

Design & Development

Kingwell has an ongoing relationship with Xi'an Petroleum University and built up long term cooperation with China Aerospace Group for more than 10 years. Design Department is familiar with CAD and Pro-E facilities and has on rolls qualified & experienced engineers. Now, they are engaged in development of new products as required in the market place. Kingwell' products are validated in-house in a Test Well, a Sub-surface Type Test Facility with simulated well conditions up to 15000 psi Differential pressure , 400°F and Max 450°F.

Below are our cooperative partners.

Inspection and Test Facilities

We own the world-class facilities with professional laboratory technicians. The main facilities are Surface Testing (Hydraulic Testing Unit), high temperature heat treatment furnaces, API Gages (Master & Working), Profile Projector, tensile testing machine, pressure sensor and data acquisition system, Universal Testing Machine, Hardness Tester, Nitrogen Pump, Function Test Pump, Ultrasonic Thickness Tester etc. All the goods must be tested by several processes and must be qualified when packed.

Product delivery

Payment:TT/LC:30% advance payment.70%before shipment

Warranty: Warranty period is 1 year after installation.

Packaging: wood case or steel carton

Delivery Date: within 1-2 month(s) after receiving prepayment

Logo: KW, we can produce according to customer requirements.

Technical Documents: We can provide technical documents according to your requirements.

Additional service: Customers are served to test our products in our factory upon request.

The followings are some pictures about product packaging

Service

Kindly let me know if you have any interest or enquiry about our products. You are also always welcomed to come to our factory for a visit at your convenient time.

We will offer you a good price and show you our best service.