Wellsite Information Transfer Specification

Revsion 1.1

The WELLSITE INFORMATION TRANSFER SPECIFICATION (WITS)is an industry standard data communication format used by Petrospec Technologies in its software. The WITS standard is intended for use at the wellsite. It is a recommended format by which service companies and operating companies can exchange data.

WITS defines a set of pre-defined records for specific data values. Additionally, users may add data items in the fields marked SPARE.

WITS is a multi-level transmission format. This arrangement offers a basic transmission format (LEVEL 0), and additional levels with increasingly flexibility. At the lowest levels, a fixed format ASCII data stream is transmitted; at the highest level a self-defining customizable data stream is available.

A WITS data stream is made up of a series of data records. Each data record type can be created independently of other data record types and each has a unique trigger variable and sampling interval. The activity on the rig determines which records are applicable at any given time so that only appropriate data is transmitted.

WITS Pre-Defined Record Types

Record
Number Name Description
01 General Time-Based Drilling data gathered at regular time intervals
02 Drilling - Depth Based Drilling data gathered at regular depth intervals
03 Drilling - Connections Data gathered at drilling connections
04 Hydraulics Hydraulics data gathered while circulating
05 Trip - Time Tripping data gathered while running in/pulling out
06 Trip - Connections Tripping data gathered at tripping connections
07 Survey/Directional Directional/Survey data
08 MWD Formation Evaluation MWD Formation Evaluation data
09 MWD Mechanical MWD Mechanical data
10 Pressure Evaluation Pressure Evaluation data
11 Mud Tank Volumes Mud Tank (Pit) Volume data
12 Chromatograph Cycle-Based Chromatograph Cycle data
13 Chromatograph Depth-Based Chromatograph data averaged over depth intervals
14 Lagged Mud Properties Mud Property data based returns depth increments
15 Cuttings / Lithology Cuttings Lithology and related data
16 Hydrocarbon Show Hydrocarbon Show related data
17 Cementing Well Cementing operations data
18 Drill Stem Testing Well Testing operations data
19 Configuration Drillstring and Rig Configuration data
20 Mud Report Mud Report data
21 Bit Report Bit Report data
22 Remarks Freeform Comments
23 Well Identification Well Identification data
24 Vessel Motion / Mooring Status Vessel Motion and Mooring Status data
25 Weather / Sea State Weather and Sea State data

Record Number	Name	Description
01	General Time-Based	Drilling data gathered at regular time intervals
02	Drilling - Depth Based	Drilling data gathered at regular depth intervals
03	Drilling - Connections	Data gathered at drilling connections
04	Hydraulics	Hydraulics data gathered while circulating
05	Trip - Time	Tripping data gathered while running in/pulling out
06	Trip - Connections	Tripping data gathered at tripping connections
07	Survey/Directional	Directional/Survey data
08	MWD Formation Evaluation	MWD Formation Evaluation data
09	MWD Mechanical	MWD Mechanical data
10	Pressure Evaluation	Pressure Evaluation data
11	Mud Tank Volumes	Mud Tank (Pit) Volume data
12	Chromatograph Cycle-Based	Chromatograph Cycle data
13	Chromatograph Depth-Based	Chromatograph data averaged over depth intervals
14	Lagged Mud Properties	Mud Property data based returns depth increments
15	Cuttings / Lithology	Cuttings Lithology and related data
16	Hydrocarbon Show	Hydrocarbon Show related data
17	Cementing	Well Cementing operations data
18	Drill Stem Testing	Well Testing operations data
19	Configuration	Drillstring and Rig Configuration data
20	Mud Report	Mud Report data
21	Bit Report	Bit Report data
22	Remarks	Freeform Comments
23	Well Identification	Well Identification data
24	Vessel Motion / Mooring Status	Vessel Motion and Mooring Status data
25	Weather / Sea State	Weather and Sea State data

WITS Transmission Levels

Level 0: Also known as"Intra Rig Transfer Specification", this involves a very basic ASCII transfer format intended primarily for sharing of information between service companies, though lending itself well as a simple entry point into wellsite data transfer. Data items are identified by a numeric string tying the value to a particular location within a Pre-Defined Record, or to an agreed upon addition to the Data Dictionary.
Level 1: In Level 1 and above, the data stream takes on a binary (LIS) format. Values are expressed in LIS-defined representations (e.g. floating point, integer, string, etc) The data items are packaged into a WITS Data Record and then sandwiched between LIS Physical and Logical Record Headers and Trailers, to make up a LIS Data Record.
Level 2: WITS Level 2 builds on Level 1 through addition of WITS bidirectional dialogue through the use of LIS Comment records. This dialogue is used in synchronization at start up and after a communications line interruption, as well as permitting two-way messaging between the sender and receiver. Such messages might include requests for change in transmission intervals for certain records, for example.
Level 2b: WITS Level 2b adds the option to buffer data that has been transmitted, making it available for re-transmission in the event of non-receipt of data by the receiver.
Level 4: WITS Level 4 employs a completely different format than the previous levels since it is based on the emerging data transfer standard of API RP66. The concepts of Pre-Defined Records and Bi-Directional Dialogue remain, but using RP66 as the formatting mechanism.