Our spray-welding method uses Ni-based self-fluxing alloy powder as raw material and involves controlled remelting at 1000-1150°C. As a result, a high-density metallurgical bond is formed (not merely a physical coating) with boride and silicide hard phases being dispersed evenly. Such an overlay delivers homogeneously with the highest qualities in impact, wear, and corrosion resistance with absolutely no delamination risk.
Besides that, the plunger is being meticulously straightened and centerless ground with a Ra ≤ 0.4 μm mirror finish obtained, thereby providing maximum sealing capability necessary for long stroke and deep well production
1. A spray welding plunger connected by a short plunger of 1.2 meters or 1.5 meters in length.
2. An integrated spray welding plunger that is spray-welded, straightened, and ground.
1. The outer surface is treated with a spray welding and remelting method to lay down a layer of nickel-based alloy powder;
This process guarantees that the plunger will keep rich corrosion resistant, and dimensionally stable properties for a long time.
2. The long plunger has a high level of overall dimensional accuracy, superb straightness and coaxiality, and a low flow resistance factor during operation; in addition, its perfectly smooth outer surface hinders scale buildup and makes pump jamming impossible.
If you face the following situations, an engineering-grade long-type spray-welded plunger will be your unique implementation:
Deep and Ultra-Deep Wells: Achieving long sealing travel is a must to fight fluid loss caused by high hydrostatic column pressure.
Long-Stroke Pumping Units: Plunger adjustment for stroke elongation is the chief feature of the device to hold the plunger's moving path relatively stable in the pump barrel.
Wells with Severe Sand Production/Backflow: A longer plunger will be more effective because it will guide sand particles more efficiently and thus will stop foreign particles from contacting the seal.
High-Temperature Thermal Recovery (SAGD/CSS): This design is made to make metal thermal expansion more stable in heavy oil thermal recovery through better sealing clearance compensation.
| Dimension | Standard Chrome Plunger | Long Spray Metal Plunger | Procurement Value |
| Sealing Length | Typically 2–4 ft | Customizable up to 20–30 ft | Excellent control of leakage under high differential pressure |
| Bonding Method | Electroplating (physical adhesion) | Thermal spray welding (metallurgical bonding) | Zero delamination risk, suitable for high-impact conditions |
| Surface Hardness | HRC 60–65 (very thin layer) | HRC 58–62 (0.020" thick hardened layer) | Long-term wear resistance with re-machinable capability |
| Deep Well Pump Efficiency | Drops significantly with increasing pressure | Maintains high volumetric efficiency | Directly improves the daily production rate |
| Maintenance Interval | Frequent (3–6 months) | Long-term (12–24 months) | Reduces overall lifting cost by over 50% |
One of the major technical difficulties in producing plungers longer than 20 feet is how to keep them perfectly straight and with the right alignment of the concentric circles.
Precision Substrate Pre-treatment: We acquire seamless steel tubes of very high tensile strength, which are subjected to stress relieving, a heat treatment operation, before being spray welded. This is done to avoid the tube undergoing any shape changes when exposed to high temperatures during welding.
Continuous Spray Welding Technology: A piece of equipment that rotates the workpiece continuously while spraying the alloy metal powder is used to carry out automated welding that involves deposition of layers of the nickel-based alloy to the whole length of the material without the development of any hot spots or porosity.
Multi-Point Supported Grinding: To make sure that the diameter sizes along the whole lengths of the plungers remain within the highly demanding requirements of the API 11AX, we use the centerless grinding machines with a very large scale and a multi-point steady rest facility for long plungers.
φ28×（2.4~12）m.
φ32×（2.4~12）m.
φ38×（2.4~12）m.
φ44×（2.4~12）m.
φ57×（2.4~12）m.
φ70×（2.4~12）m.
φ83×（2.4~12）m.
φ95×（2.4~12）m.
Dongsheng came into being in 2000, and from that time up to the present, Dongsheng has been 26 years deeply engaged in the manufacture of petroleum machinery and through this time they have developed mature production processes and broad industry knowledge. The firm has earned the ISO 9001 Quality Management System certificate and has set up a thorough quality trackability system that covers the whole product life cycle, starting from raw materials up to the delivery of the final products.
Modern Production Base: The company is located in a site covering more than 20,000 square meters with industrial-standard facilities that can house large-scale manufacturing operations.
High-Proportion Technical Team: We now have a total of 96 working staff, among whom 20 are engineers and highly specialized technical personnel. In terms of percentage, technical professionals make up more than 20% of our employees, hence we have sufficient technical support for all our endeavors - from product development to tailor-made manufacturing.
Our large-scale manufacturing facilities are equipped with the capability to produce more than 20,000 units of equipment each year, which means we can confidently meet very large procurement orders. We also provide a complete range of customization services to support our clients' specific needs, which include producing unique designs and products.
Lead time for delivery is tightly monitored and goods are dispatched within 8-10 weeks. We pack the products in sturdy wooden crates which provide protection during the transportation.
Main Supplier for Domestic Oilfields: Our products have been highly indispensable to major domestic energy hubs such as the Liaohe, Daqing, Changqing, and Shengli oilfields.
Export Network Globally: Our business has extended to a variety of countries and regions such as the United States, Canada, Romania, India, and Indonesia, which is a clear indicator of our demonstrated ability to handle and provide services to overseas orders.
Send us your well parameters for model selection
Contact us to get a quotation within 24 hours
