Online sampler under tank

Ⅰ.Product Introduction

In the petrochemical industry, traditional oil sampling operations for petroleum storage tanks are mostly carried out by manual climbing on the tank top. This tank top sampling method has many inconveniences. For example, the accuracy of tank top sampling is difficult to control; the labor intensity for operators is high, and the sampling time is long; there are safety hazards when sampling on the tank in rainy, snowy, windy, and other weather conditions; volatile and toxic gases can cause harm to operators during tank top sampling.

To address the aforementioned sampling issues, our company has developed the "under-tank sampler" in accordance with the standards of GB/T4756-2015 "Manual Sampling Method for Petroleum Liquids" and SH/T3414-2017 "Selection, Inspection, and Acceptance Criteria for Samplers Used in Steel Vertical Storage Tanks in the Petrochemical Industry". By absorbing advanced technologies of under-tank samplers from both domestic and international sources, and considering the actual sampling conditions in the domestic petrochemical industry, we have developed this sampler. The under-tank sampler is a facility used to collect oil samples from within petroleum storage tanks, consisting of both external and internal parts. It allows samples from different points within the tank to be directly collected in an externally located, enclosed sampling control box, eliminating the need to climb the tank, ensuring no leakage or emissions, and providing safety and environmental protection.

II. Classification of the internal part of the sampler under the tank

1. Telescopic diamond frame

Based on the characteristics of the proportional expansion frame, the sampling point is fixed on the expansion diamond frame. The top of the expansion frame is fixed on the float ball/float disc, and the bottom of the expansion frame is firmly fixed at the bottom of the storage tank. When the oil level in the storage tank fluctuates up and down, the sampling point on the expansion frame will change with the change of the liquid level, thus ensuring the accuracy of sampling.

Features:

The sampling pipelines at each sampling point are independent of each other and are connected to a sealed sampling box outside the tank.

It occupies less internal space of the tank, is easy to install, and has a smaller sampling point error.

A float ball/float disc can be installed on the top of the telescopic frame, which has a small footprint and is suitable for most domestic storage tanks.

2. Folding arm type/Straight arm type

The top of the folding/straight arm is equipped with a float ball or connected to the tank's floating disc, with the base fixed at the bottom of the tank. The sampling point and sampling pipeline are attached to the folding/straight arm. When the oil level in the tank fluctuates, due to the movable components of the base on the folding/straight arm, the sampling point will change accordingly with the level variation.

Folding arm type: simple structure, easy to install, low price, but occupies more internal space of the tank. Due to the long length of a single section of the folding arm, it requires the entire cross-section of the tank. If the folding arm shakes, it may adversely affect other devices inside the tank.

Straight-arm type: simple structure, easy to install, low cost, occupies more internal space of the tank, requires the entire cross-section of the tank - sampling height is limited by the length of the straight arm, unable to collect oil samples from higher levels inside the tank.

3. Fixed-point type

The fixed-point tank sampler is suitable for collecting asphalt, residual oil, heavy fuel oil, or for storage tanks with special user requirements.

The structure is simple, easy to install, and inexpensive. With no moving parts, the vertical sampling rod remains stable despite the fluctuation of the oil products inside the tank, ensuring no impact on other devices within the tank

Ⅳ.Classification of the external part of the sampler under the tank

1. Electric pump

The explosion-proof booster pump is adopted, which is not affected by the pressure of the gas source and features high torque and abundant power. However, the sampler requires power supply, which needs to be confirmed with the user site.

2. Fully automatic

It can collect samples from the top, middle, and bottom, as well as from the bottom. The electronic control structure is complex and equipped with an emergency stop button. All operations are centralized on the touch panel, allowing for timed and quantitative collection of oil samples. The fully automatic one-button automatic cycle and automatic sample placement ensure the collection of fresh samples and enable remote operation. The touch screen displays the real-time oil temperature inside the tank, sampling status, sampling quality, and sampling time. The operation is simple and controllable by humans.

3. Hand pump

No additional electric/pneumatic pumps are required, featuring a simple structure, low price, easy manual control, and no significant noise generation. However, it requires more manual operation.

4. Pneumatic pump

The sampling pipeline is pressurized using pneumatic technology, allowing for continuous start-stop operations and linear pressure output. The sampler is located away from the power source, thus generating no heat or electrical sparks, ensuring safety and environmental friendliness.